Piaget, Jean

1896–1980

SWISS GENETIC EPISTEMOLOGIST, PSYCHOLOGIST

UNIVERSITE DE NEUCHATEL, B.A., 1915, Ph.D., 1918; POSTDOCTORAL STUDY AT UNIVERSITY OF ZURICH, UNIVERSITY OF PARIS, AND THE SORBONNE

BRIEF OVERVIEW

The Swiss psychologist and epistemologist Jean Piaget (1896–1980) developed his theory of genetic epistemology throughout a nearly 60-year career as a professor and experimental researcher. He first began his scientific investigations as a young biologist immersed in the study of mollusks. Before he was 30 years of age, he was world renowned for his explorations of the cognitive development of children. Piaget is credited with foundational contributions to the emerging disciplines of child psychology, educational psychology, and cognitive development theory. Piaget's empirical studies of infants, children, and adolescents provided insight into the nature of knowledge and how it is acquired. He took children's thinking seriously and respected them as the architects of their own intellectual development.

Jean Piaget was the only son of Arthur Piaget, a professor of medieval studies at the University of Neuchatel, and Rebecca Jackson. He spent his childhood and adolescence in Switzerland in the region near Lake Neuchatel. He was trained as a zoologist, receiving his Ph.D. from the University of Neuchatel in 1918. His early fascination with and competence in the biological sciences, particularly the study of mollusks, continued throughout his lifetime. Piaget moved to Paris in 1919 for postdoctoral studies.

The turning point in his academic life came through his work with French school children, in which he administered and standardized British intelligence tests as a research associate at the Simon-Binet experimental psychology laboratory. During the course of his work with intelligence testing, Piaget decided that the important issue to explore was not whether children gave the right answers to the IQ test, but rather, how they gave the wrong answers and what the patterns of the children's responses revealed about their developing capacities for reasoning.

In 1921, Piaget returned to Switzerland, where he made his home until his death. He was appointed Research Director of the Institut Jean-Jacques Rousseau in Geneva in 1921 and that same year published his first article on the psychology of intelligence. Piaget was known as le patron (the boss) by his graduate students and research associates. His early work studying the reasoning of elementary school children became the basis of his first five books on child psychology and marked the beginning of his international fame as a revolutionary thinker in the area of childhood cognitive development.

Piaget used the term genetic epistemology to define his disciplined investigation into how knowledge develops within the human being and the means by which the developing mind moves through distinct stages toward maturation. At the heart of Piaget's biological theories of development is his emphasis on the human being's ability to adapt to the world through the dual processes of assimilation and accommodation, modifying one's mental schemes to allow room for new information.

Piaget's child-centered research and respectful observations of infants and children led him to the discovery that children think in qualitatively different ways than adults as they progress through four distinct and universal stages of development.

• Sensorimotor stage (birth to about two years): Infants rely on their senses to understand the world around them.
• Preoperational stage (about two to seven years): Pre-school children develop an increased capacity for symbolic thinking and the use of language and images.
• Concrete-operational stage (about seven to 11 years): Children think logically and begin to see the world from others' perspective.
• Formal operational stage (age 11 to adult): Hypothetical and abstract reasoning with systematic problem solving and abstract thinking.

Piaget's consuming interest was in the discovery of the universal mechanisms that underlie how knowledge is acquired. He understood this as a process governed by genetic factors and environmental experiences, with the environment playing an increasingly more important role as the individual matures. Piaget respected the developing child as an active agent in the construction of knowledge through trial and error experimentation. Even the fundamental ideas of space, time, relation and causality, he observed, are subject to this process. The child's earliest years, he believed, laid the foundation for the rational and moral adult personality, with increasingly complex intellectual processes building on the successful passage through earlier, more primitive stages of development. Piaget did not consider the fourth stage of formal operations as a final one. He believed there was no fixed limit to the possibilities of human development.

Throughout a brilliant research career that spanned more than 60 years, Piaget refined his structural and holistic methodology for observing, describing, and evaluating the stages of human cognitive development from the point of view of the child. His pioneering research and prolific publications on the nature of thought and the development of intelligence assured Piaget's place as a major influence in the scientific thinking of the twentieth century. The ingenuity of his approach to the study of children's ways of thinking continues to inform and influence the fields of epistemology, education, and developmental and child psychology.

Piaget continually changed his thinking as new possibilities occurred to him. His impressive list of publications include over 60 books, professional papers, book chapters, and articles in scientific journals. He received over 30 honorary degrees and awards from universities throughout the world. In 1955 Piaget created the International Center for Genetic Epistemology and served as its director for the remainder of his life. He died in Geneva, Switzerland, on September 16, 1980. His genuine respect for and appreciation of the mind of the child and his prodigious research accomplishments continue to inspire and challenge scholars and researchers worldwide.

BIOGRAPHY

Child prodigy

Jean Piaget was born in Neuchatel, Switzerland, August 9, 1896, the first of three children of Arthur Piaget and Rebecca Jackson. The Piaget family lived in a quiet French-speaking region near Lake Neuchatel, in the cradle of the Swiss Alps in an area of Switzerland noted for its vineyards and watch making.

Jean was a child prodigy. His father, a professor of medieval literature at Neuchatel University, nurtured his son's innovative and inquisitive mind and encouraged young Jean in the systematic pursuit of answers to his many queries about the natural world.

Jean's mother was a strict Calvinist, adhering to a system of biblical interpretation focused on the supreme sovereignty of God and the fallen nature of humans. She was politically active and concerned with the social causes of the day. By some accounts Rebecca Piaget was a troubled woman, seriously challenged with mental illness. She encouraged her son to attend religious instruction, but young Piaget soon lost interest in what he considered "childish" religious arguments. Piaget began his study of various philosophies in an effort to find his way through the inconsistencies he perceived between the religious instruction he received at church and his own observations of the natural world. At the suggestion of his godfather, the Swiss scholar Samuel Cornut, Piaget began his study of philosophy. He was especially touched by the French writer Henri Bergson's 1907 book, Creative Evolution. Piaget said the book "stirred him almost to ecstasy."

He told interviewer Elizabeth Hall much later in his professional life:

Suddenly the problem of knowledge appeared to me in a new light. I became convinced, very quickly, that most of the problems in philosophy were problems of knowledge, and that most problems of knowledge were problems of biology. You see, the problem of knowledge is the problem of the relation between the subject and the object, how the subject knows the object. If you translate this into biological terms, it is a problem of the organism's adapting to its environment. I decided to consecrate my life to this biological explanation of knowledge.

Jean grew into a serious young man, disciplined and determined in his pursuit of knowledge. He chafed within the strictures and routines of his early schooling and became bored and restless in the classroom. His early interest in the scientific study of nature led him to membership in a local biology club while a student at Neuchatel Latin high school. When he was only a boy of 10, Jean published a paper in the club's Journal of Natural History of Neuchatel describing his observations of an albino sparrow. Jean took his work quite seriously. He sought and gained access to the university library where he could explore more books and journals to further his studies.

In later years, Piaget described his youthful home life as being not particularly happy. As a young student he spent most of his time away from the difficulties at home, immersing himself in study and seeking to solve the mysteries of nature. He was intrigued with the study of fossils, bird life, and even with the invention of a steam engine car. He read constantly in the fields of philosophy, psychology, and natural sciences, a habit he sustained throughout his life.

During high school, Jean's remarkable scholastic accomplishments continued to bring him to the notice of his teachers and others in the field of natural sciences. He became a leader in the Friends of Nature Club, sponsored by professors at the University of Neuchatel, and he prepared and read papers on natural science at the club meetings. He became an assistant to Paul Godet, the director of the Neuchatel Museum of Natural History. He worked there for four years as an apprentice, helping to classify the museum's considerable collection of mollusks. As compensation Piaget received numerous rare mollusk specimens to add to his personal collection. He began to publish a series of scientific papers on the mollusks, particularly the Limnaea species, a Swiss lake snail.

When he was 16, Piaget's scholarly work drew the attention of the board of directors of the Museum of Natural History in Geneva. He was offered the prestigious post of curator of a mollusk exhibit at the museum. The admirers of his scholarship were unaware that Jean was still a high school student when they honored his work with an offer of employment. By the time of his high school graduation, Jean Piaget had become a well-known malacologist throughout Europe with 20 scientific papers published in professional journals. Such early success with his study of clams and snails gave young Piaget a firm basis for the continued development of his scientific approach to the study of nature. He sustained his interest in mollusks throughout his life.

In 1918, at the age of 21, Jean Piaget graduated with a doctorate in natural sciences from the University of Neuchatel. That same year he published his first book, Recherche, meaning "the search" or "searching," an autobiographical novel dealing with the conflict between science and religion. In this book Piaget first explored the idea of equilibrium, a concept that he understood as an ideal balance between parts and the whole, both within an individual and within society.

Piaget published his doctoral thesis on the classification of mollusks. During the intense periods of academic exploration and focus throughout his university years, Piaget's physical health suffered. He was forced to take a year off from his studies and retreated to the mountains to recuperate. This rest period in the Swiss Alps became a yearly habit throughout his life, providing him with critical time for reflection and rest. Piaget valued his relationship with the natural world as a necessary ingredient in a balanced life.

PRINCIPAL PUBLICATIONS

• Le Langue et la pensee chez l'enfant. Paris: Delachaux and Niestle, 1923. Published in English as The Language and Thought of the Child. Trans. by Marjorie Worden. New York: Harcourt, Brace, 1926, 3rd revised edition, Humanities 1959, reprinted, 1971.
• Le Jugement et le raisonnement chez l'enfant. Paris: Delachaux & Niestle, 1924, 5th edition, 1963. Published in English as The Judgement and Reasoning in the Child. Trans. by Marjorie Worden. New York: Harcourt, Brace, 1928, published as The Judgment and Reason in the Child. 1929, reprinted, Littlefield, 1976.
• Le Representation du monde chez l'enfant. Paris: Delachaux and Niestle, 1926. Published in English as The Child's Conception of the World. Trans. by Jean Tomlinson and Andrew Tomlinson. New York: Harcourt, Brace, 1929, reprinted, Littlefield, 1976.
• La Causalite physique chez l'enfant. Paris: Delachaux & Niestle, 1927. Published in English as The Child's Conception of Physical Causality Trans. by Marjorie Worden Gabain. New York: Harcourt, Brace, 1930.
• La Naissance de l'intelligence chez l'enfant. Paris: Delachaux and Niestle, 1936, 5th edition, 1966. Published in English as The Origins of Intelligence in Children. Trans. by Margaret Cook. New York: International Universities Press, 1952. Published in English as The Origin of Intelligence in the Child. London: Routledge & Kegan Paul, 1953, Norton, 1963.
• La Formation du symbole chez l'enfant: Imitation jeu et reve, image et rpresentation. Paris: Delachaux and Niestle, 1945, 2nd edition, 1959. Published in English as Play, Dreams, and Imitation in Childhood. Trans. by Gattegno and Hodgson. New York: W. W. Norton & Co., 1951, reprinted, Peter Smith, 1988.
• With Barbel Inhelder. La Psychologie de l'enfant Presses universitaires de France, 1966, 6th edition, 1975. Published in English as The Psychology of the Child. Trans. by Helen Weaver. New York: Basic Books, 1969.
• L'Epistemologie genetique. Presses universitaires de France, 1970. Published in English as The Principles of Genetic Epistemology. Trans. by Wolfe Mays. New York: Basic Books, 1972.
• L'Equilibration des structures cognitives: probleme central du developpement. Presses universitaires de France, 1975. Published in English as The Development of Thought: Equilibration of Cognitive Structures. Trans by Arnold Rosin. New York: Viking, 1977.

Early career

Piaget enrolled for a semester of postdoctoral study at the University of Zurich in Switzerland. While in Zurich he also worked in Eugen Bleuler's psychiatric clinic. His curiosity about psychological issues, due in part to his mother's poor mental health, led him to the study of the psychoanalytical theories of Sigmund Freud and the analytical psychology of the Swiss psychoanalyst Carl Gustav Jung. Piaget attended many of Jung's lectures, and he was particularly interested in Jung's emphasis on the human psyche's drive toward balance and wholeness, and on the individual's significance as the agent of his or her own maturation and individuation. During these years Piaget was reading psychology only in French and was not exposed to the contemporary writings of Max Wertheimer and Wolfgang Kohler, the Gestalt psychologists. He later told an interviewer that had he come across the Gestalt writings when he was 18 he might himself have become a Gestalt psychologist.

In 1919 Piaget moved to Paris, where he studied logic and abnormal psychology and lectured in psychology and philosophy at the Sorbonne. He found work as a research associate in the Simon-Binet experimental psychology laboratory. There Piaget worked with Theophile Simon in administering intelligence tests to French children at the École de la rue de la Grange-aux Belles a school for boys. Piaget's task was to standardize the French version of British psychologist Cyril Burt's intelligence test, noting what kind of errors children made as they answered a series of questions. Though he was not particularly challenged by the work of test administration and never completed the task of standardizing the test, in the process of his work he began to realize the qualitative differences in how children and adults think.

Piaget's work with these young children (ages five to eight years), was a turning point in his career, leading to his lifelong study of the origins, nature, and development of intelligence. Piaget believed this research into how children think was an essential source of information about the nature of knowledge itself. He was intrigued with the answers the children gave, even if those answers were considered wrong by the standards of the intelligence test he administered. It was the patterns of their responses that caught his attention. Children of the same age, he found, invariably came up with the same wrong answer to the test questions. Piaget began to explore the thinking processes of the children, making use of a technique of clinical interviewing he had learned during his work at Eugen Bleuler's psychiatric clinic in Paris. He was fascinated with the processes of children's reasoning and the unique psychological mechanisms at work as they construct, apply, and adapt their own theories of the world in a trial and error process leading to the acquisition of practical intelligence.

Piaget came to believe that children of all ages are interactive agents in their personal intellectual development. His experience with testing these French children led him to develop his own experimental working philosophy of how knowledge grows, which later evolved into his systematic theories of cognitive development known as genetic epistemology.

In 1921 Piaget published a paper in the Archives de Psychologie. In the paper, he claimed that logic is not an innate characteristic but is developed over time through interactive processes of self-regulation. Piaget believed that this adaptive process is common to all living things. He discounted the prevailing doctrines of innate ideas and environmental determinism. His published work drew the attention of other researchers and scholars, and at the age of 25, Jean Piaget was offered the position of research psychologist at the Jean-Jacques Rousseau Institute in Geneva (now Institut des Sciences de l'Education at the University of Geneva). The Institute was highly regarded for its programs of educational research. There Piaget studied children's language and reasoning processes, and began writing in earnest. He later became co-director of the Institute and produced five more books during his five-year tenure there.

Marriage and family life

Piaget married psychologist Valentine Chatenay in 1923. Piaget's young wife had been one of his first graduate students at the Jean-Jacques Rousseau Institute in Geneva where Piaget worked. She soon became his research associate in the observation and detailed study and analysis of the behavior of their three children: Jacqueline, Lucienne, and Laurent. The young couple documented the intellectual development of their children from infancy throughout their childhood years. They listened to their children, watched them at play, and played with them, respecting how their cognitive processes differed from an adult's. They attempted to describe and evaluate the point of view of their developing children and to gain insight into how knowledge is acquired. They recorded the children's words and actions, without criticism, as they observed the unique thought processes and underlying logic that the children revealed.

The painstaking observation of Piaget's own three children prior to their acquisition of language led to his development of the theories of sensorimotor intelligence and publication of three books detailing his observations. Piaget respected children as active agents in their personal intellectual development. His early publications provided a coherent account of human development in the first year of life.

In photographs taken throughout his adult life, Piaget is often shown wearing his characteristic beret, with an engaging smile and horn-rimmed glasses framing his twinkling eyes. He was a tall man who always seemed to have a pipe in hand. In later years, his snow-white hair added to his distinctive appearance. Piaget was a somewhat eccentric and tireless worker fully absorbed in his academic pursuits. He was kind and possessed of enormous charisma, but by some accounts was remote and obsessed with his work.

"Fundamentally I am a worrier whom only work can relieve," Piaget said. He was an early riser, customarily beginning his day at 4 AM. His desk was said to be piled high with stacks of books and papers organized in a way only he could decipher. He spent four hours each day composing new material writing with pen and paper. In addition, he supervised the work of graduate students, taught classes, attended meetings, continued with his empirical research, and fulfilled the multiple obligations of his employment at the university. Even his leisure time was spent in productive ways. He combined exercise with transportation and often rode his bicycle to work. In the afternoons he took long walks as he puzzled out the complex theories that consumed his intellectual life. But Piaget the naturalist was never completely consumed with his intellectual pursuits.

It is true I am sociable and like to teach or to take part in meetings of all kinds, but I feel a compelling need for solitude and contact with nature. . . .As soon as vacation time comes, I withdraw to the mountains in the wild regions of the Valais and write for weeks on end. . . .It is this dissociation between myself as a social being and as a "man of nature" which has enabled me to surmount a permanent fund of anxiety and transform it into a need for working.

Return to Switzerland and international acclaim

Piaget returned to his home in Switzerland in 1925 to work at his alma mater, Neuchatel University, where he was to occupy academic chairs as professor of psychology, sociology, and the history of sciences during a five-year tenure. In 1928, Piaget had the good chance to meet Albert Einstein who, Piaget said, "impressed me profoundly, because he took an interest in everything." Einstein recognized the genius in Piaget's insights and work. He suggested to Piaget that he should study the notions of time in children, and in particular the notions of simultaneity. Piaget, before the age of 30, had become the most well-known psychologist in the French-speaking world.

In 1929 Piaget taught the history of scientific thought at the University of Geneva. He remained there until 1939. During this time Piaget and his associates studied children from four to 12 years of age researching the development of logical thinking in childhood and adolescence, particularly with regard to concepts of speed, quantity, number, geometry, space, time, and movement. It was also during this period that Piaget began major collaborative research with other psychologists. He collaborated with Professor Barbel Inhelder, an experimental child psychologist at the University of Geneva. Together they wrote The Child's Construction of Physical Quantities. Conservation and Atomism, published in 1942, and The Growth of Logical Thinking from Childhood to Adolescence, published in 1955, and began a collaborative relationship that lasted 40 years. Piaget also worked with Alina Szeminsa on several books. Piaget was influential in bringing the work of women psychologists into more prominence in the field of experimental psychology, which was dominated by male theoreticians.

During the years of World War II, Piaget's work was not easily available outside of Switzerland. His ideas, though well accepted in Europe, were not often heard in American universities, where the behaviorist theories of human development dominated. None of his books was translated into English for the nearly 20 years between 1932 and 1950. In 1942 he lectured at the College of France during the time of the Nazi occupation. These lectures were compiled into his book, The Psychology of Intelligence, published in 1963.

Piaget served for 35 years (1929–67) as director of the International Bureau of Education in Geneva, working in collaboration with the United Nations Educational, Scientific and Cultural Organization (UNESCO), and in 1932 he became director of the Institute of Educational Sciences at the University of Geneva. He continued in that capacity until 1971, when he was named Emeritus Professor at the University of Geneva, a position he held until his death in 1980.

Throughout his long career Piaget won numerous awards and gained international acclaim. He received the Distinguished Scientific Contribution Award by the American Psychological Association in 1969. He was the first European to receive the award that honored him for his "revolutionary perspective on the nature of human knowledge and biological intelligence." In 1972 Piaget was awarded the Praemium Erasmianum (known in English as the Erasmus Prize), from The Netherlands. This prestigious award was established to "honour persons or institutions that have made an exceptionally important contribution to European culture, society or social science."

Piaget edited numerous scientific journals; received honorary degrees from over 30 universities, including Cambridge and Harvard; and held memberships in more than 20 academic societies. In 1955 he founded the International Center for Genetic Epistemology at the University of Geneva, and in 1956 he persuaded the Rockefeller Foundation to provide financial assistance for his interdisciplinary work there. He continued his active association with UNESCO as a member of its Executive Board, as director of the International Bureau of Education (IBE), and for a short time as Assistant Director-General for Education.

Jean Piaget has been called a foundational thinker. He remained intellectually active, continuing with his research and publishing, until his death in Geneva at the age of 84 on September 17, 1980. More than 3,000 people gathered at his funeral in Geneva to honor his life and work, according to obituary reports of the day. Piaget was buried with his wife, Valentine, in a gravesite marked with a cairn of simple stones. They rest together in the Cimetiere des Plainpalais, on the Rue de Rois, a cemetery reserved for Geneva's most distinguished departed.

Piaget's theories of cognitive development have had a major impact in the fields of education, sociology, and developmental and child psychology. He is a founder of the scientific discipline he called genetic epistemology, the term he used to describe his academic pursuit of the origin and nature of knowledge. His pioneering theories and the enormous respect he held for the thinking processes of children have distinguished Jean Piaget as one of the most significant psychologists of the twentieth century.

THEORIES

Genetic epistemology

Piaget developed his theory of genetic epistemology throughout 60 years of focused work as an experimental psychologist and interdisciplinary theoretician. He was concerned with the fundamental question of the nature and origin of knowledge. His own thinking on the subject was constantly changing. Sometimes in the course of writing a book, one scholar has observed, "Piaget had different ideas when it came time to write the conclusion than he had when he wrote the introduction." He wrote in French about abstract ideas using technical terminology, and this has made his books challenging to read and interpret. Fortunately there are many good translations of his works available, and scholarly writing help students navigate the complexities of Piaget's comprehensive theories of cognitive development.

Piaget was prolific. He authored, collaborated with others, or edited more than 60 books, or book chapters. He published frequently in professional journals and produced a large quantity of lecture notes and research papers. The Jean Piaget Archives Foundation in Geneva is a repository for his collected works. Piaget's writings have been translated in 24 languages, extending his influence and thinking throughout the world. Piaget's research career extended from the 1920s to the 1980s. He published his first article on the psychology of intelligence in 1921, and was still at work developing new theoretical ideas at the time of his death in 1980.

First principle: To take psychology seriously

Main points The first principle of genetic epistemology is "to take psychology seriously," Piaget said in the 1968 Woodbridge Lectures at Columbia University. By this he meant "when a question of psychological fact arises, psychological research should be consulted instead of trying to invent a solution through private speculation." Piaget considered his work that of an empirical scientist. The fundamental hypothesis that he investigated throughout the course of his career is what he called "the parallelism between the progress made in the logical and rational organization of knowledge and the corresponding formative psychological processes." Piaget's empirical studies of infants, children, and adolescents were the best way he found to study the development of logical knowledge, mathematical knowledge, physical knowledge, and the nature of knowledge itself.

Piaget attempted to understand the evolution of knowledge in all human beings through the study of the individual. As a biologist, Piaget's approach follows directly from a neo-Darwinian emphasis on evolution via small, gradually accumulated changes, an idea which is now a subject of some debate within the discipline of developmental biology. Piaget sought to demonstrate the continuity between biological intelligence, manifesting in plants and lower animals, and human knowledge developing throughout the lifetime of the individual. Intelligence develops through a slow process of self regulation informed by environmental interactions that lead to internal reconstruction. This ability to adapt, he believed, is the common link between all living things, and it forms the basis of the biological theory of knowledge that he called genetic epistemology.

Piaget was interested in general mechanisms, intelligence, and cognitive functions, not in what makes one individual different from another. He believed that his theory of genetic epistemology was the legitimate psychological study of species behavior as opposed to the study of the individual as in more conventional understandings of psychology.

Robert L. Campbell, of the Department of Psychology at Clemson University, has identified four main points in Piaget's theory:

• Knowledge has a biological function, and arises out of action.
• Knowledge is basically "operative." It is about change and transformation.
• Knowledge consists of cognitive structures.
• Development proceeds by the assimilation of the environment to these structures, and the accommodation of these structures to the environment.

Piaget asserts that it is organization and adaptation, two processes he considers to be basic invariants of functioning, that provide the continuity between biology in general and intelligence in particular. Through the process of adaptation, the organism evolves and adjusts to its environment. For every adaptive act there is an underlying organized system of relationships or totalities. Any act of biological intelligence, from the exploratory movements of early infancy to the complex and abstract judgment of an adult, is always in relationship to an organized structure of the whole of which a single action is only a part.

Piaget defined intelligence as an adaptation. Mental life, he said is an accommodation to the environment. Adaptation involves the process of fitting new information into one's existing knowledge base through a dual process of assimilation and accommodation, altering the ideas (or what Piaget called schemes) one has constructed to make room for new information. Piaget asserted that learning is not passive; it is a process of dynamic discovery.

Piaget wrote about this cognitive evolution in his book The Construction of Reality in the Child.

These global transformations of the objects of perception, and of the very intelligence which makes them, gradually denote the existence of a sort of law of evolution which can be phrased as follows: assimilation and accommodation proceed from a state of chaotic undifferentiation to a state of differentiation with correlative coordination.

Schemes are the "cognitive mental maps" that are the building blocks of intelligence. Development, then, involves a predictable and sequential series of assimilation and accommodation. Knowledge develops continually, with the invention and construction of reality emerging from active participation in the world. In Piaget's view, the basis of all human knowledge is experience, activity, and practice.

Another important concept in Piaget's theory is equilibrium, a balance between a person's internal ideas and their perceptions of the outside world. It is a state in which allows all information a place in the cognitive structure. Piaget defined it "a harmony between internal organization and external experience."

According to Piaget, the dual concepts of assimilation and accommodation are "the two poles of an interaction between the organism and the environment, which is the condition for all biological and intellectual operation." An individual takes in new ideas through assimilation, then makes room among his or her schemes for the new idea through accommodation. The result is a new level of awareness or understanding that is qualitatively different from the one preceding assimilation.

Equilibration is the unification of ideas that creates cognitive growth. Equilibration can be understood as a kind of thermostat acting to restore equilibrium between the dual processes of assimilation and accommodation. It is the means whereby the individual regains balance by acting, physically or mentally, on an environmental stimulus in order to understand it within the framework of one's existing mental schemes. With equilibration the individual is returned to a state of balance, though now she has spiraled to a higher level of understanding.

For the genetic epistemologist, Piaget wrote,

knowledge results from continuous construction, since in each act of understanding, some degree of invention is involved; in development, the passage from one stage to the next is always characterized by the formation of new structures which did not exist before, either in the external world on in the subject's mind.

Piaget outlined four conditions that determine cognitive growth.

• maturation of the nervous system
• social interactions
• experiences based on interactions with the physical environment
• equilibration

Cognitive development is a dynamic adaptation to the environment that incorporates both nature and nurture. It follows a gradual and predictable sequence for all individuals throughout all stages. Piaget believed that each individual "is the product of interaction between heredity and environment. It is virtually impossible to draw a clear line between innate and acquired behavior patterns."

Cognitive structures are the central concept in Piaget's theory. The development of intelligence is a flexible and mobile process. Each developmental stage contains many detailed structural forms or schemes that mark developmental progress. Increasingly complex intellectual processes are built on the foundations of these earlier stages of development. Progression through the stages takes place in a continuous sequence, with each new level of understanding arising out of the preceding one. Much as a spiral, each level encompasses and integrates in a higher form the achievements of the prior stage. Each stage involves a qualitative advance.

The patterns of physical or mental action correspond to distinct and universal stages of development. Children think with logic that is consistent with the developmental stage to which they have progressed, and this development occurs at a different pace for each individual. A child cannot undertake certain tasks until he or she is psychologically mature enough to do so. Piaget demonstrated that children's thinking does not develop smoothly. At some junctures it seems to speed up, taking off into completely new areas. Such transitional points mark the movement from one stage of development to the next. The ages of transition from one stage to the next will vary, and none can be skipped. Once a developmental stage has been reached, the individual cannot go backwards (excepting instances of mental or physical trauma). No stage is lost once the skills have been achieved.

Scholars of Piaget disagree on the number of distinct stages of cognitive development. Some view the stage of concrete operations as one stage subdivided into the preoperational and concrete operational phases. Each of Piaget's stages has many levels and subdivisions that mark a child's progress. The important point is not if there are three or four distinct stages, but rather, an understanding of the sequence of skills acquired in the process of intellectual development.

Piaget's stages of cognitive development

Sensorimotor stage (birth to two years) It is in this very first stage of development, according to Piaget, that "the most fundamental and the most rapid changes take place." The newborn infant is primarily a bundle of reflex actions interacting with the environment in an active and practical manner. Sucking and grasping are the first of these primary instinctive tendencies. Sucking is a most practical behavior needed for obtaining nourishment. With practice, the infant's sucking skills will improve. The newborn is thinking with her body and experimenting with her own stimulus. She is the center of her own universe. At this early stage the infant does not connect sensations and stimulus to anything outside of herself. Her world is one that is first to be sucked, then looked at and listened to, and then, as coordination develops, something to be manipulated.

The infant experiments with what Piaget called repetitive circular reactions She performs an action, is interested in the result, and repeats the same action again. Gradually, at about the age of four months, the infant begins to explore the immediate environment beyond her own body with secondary circular reactions. These reactions incorporate an item or stimulus from the environment, such as a squeeze toy that squeaks, a rattle, or other baby toy. As the infant handles and manipulates objects and acquires more complex motor skills, she begins to recognize herself as the agent of the action. Then, through trial and error, the infant will begin to add purpose to her movements. She comes to understand that squeezing a certain toy will result in a squeaky sound, or batting a hanging mobile over a crib may cause it to move, or pulling mother's hair will cause a grimace on the mother's face.

Piaget considered the addition of purpose to the infant's physical actions as the beginning of intelligence. Each progressive skill the developing infant acquires is known as a scheme. Schemes are "sensory motor intelligence in action," Piaget said. A scheme is above all an instrument of assimilation that ties actions together. But still, at this early stage, an object that is out of sight remains out of mind. It has simply ceased to exist in the infant's world.

One of the central development tasks of these first two years of life is the acquisition of an understanding of the concept Piaget called object permanence. This involves the ability to form a mental representation of an object that will enable the child to realize that the object still exists, even if it is out of view. It is generally not before nine months of age that the baby can understand the concept of object permanence. One clue indicating acquisition of this skill is the characteristic high-chair game where the child delights in dropping objects from the tray to the floor and then repeating the action, over and over, after the item is returned by the caregiver. "Peek-a-boo" is also a favorite game at this stage of development. The child now understands that a face can disappear and will reappear. It is not lost forever. She may also begin to display the distressing emotions of separation anxiety. The child now realizes that the person that is out of sight still exists, and she may become quite distressed and cry continuously in an effort to bring back the missing caregiver. She has learned that crying sometimes brings a desired result. The little scientist has by trial and error learned a key developmental task for this first stage in a lifetime of learning.

After the child's first birthday, she will begin to employ tertiary circular reactions. The child is now experimenting with constantly varying her interactions with items in the external environment. First she may use an object to hit another object and observe the reaction. Then with the same tool, may strike a different surface to get a different sound or reaction. She may learn, after some trial and error, to manipulate an object a certain way to fit it through an opening. This is an exciting period of active experimentation and interactive play that is critical to developing an understanding of how things behave outside oneself in the external environment.

Another concept particular to this first stage of cognitive development is object constancy. This is acquired at about one and one half years of age, when the baby comes to understand that an object will continue to be itself no matter what its position or the perspective from which the infant is viewing it. As the child approaches the transition from this first developmental stage to the next, she will also acquire the ability to imitate another person's action. This imitation grows increasingly sophisticated. As the child grows she learns to more quickly copy sounds, gestures, and expressions without as much trial and error. Then, close to the end of her second year, she reaches the stage of symbolic imitation and is able to incorporate a pretend object into her imitative play.

Preoperational stage (two to seven years) Operations is Piaget's term for thought. By this Piaget means the actions that take place in the mind rather than in the physical environment. Children in the preoperations stage of development have the advantage of their emergent language skills. Piaget noted that preoperational children have the ability to reconstruct past actions in the form of narration and to anticipate future actions through verbal representations. They can name or label objects and understand that these objects can be classified and grouped. Such grouping at this stage is by a single feature only. For instance, the child will place all the green blocks together regardless of their shape, or will group all the square blocks together regardless of their color.

Piaget delineated the preoperational years into the preconceptual period (ages two to four years) when the child first begins to use language and employ mental images, and the perceptual or intuitive period (ages four to seven years), where the child's level of reasoning is still symbolic and based on subjective intuition and appearances, rather than on objective logic or reasoning. At this stage the child believes that events happening simultaneously also have a cause-effect relationship. Everything is connected in the child's view of how the world works.

Thinking and perception in children younger than age seven is limited in many ways. They have not yet developed a full understanding of cause and effect relationships, but they have developed a high level of curiosity. This is when the child seems to always be asking "why?" They are beginning to seek logical explanations for the events that occur in the world around them.

The notion of animism, that inanimate objects are alive with attributes of consciousness and will, is evident in the child's thinking in this preoperational stage, as is the notion of artificialism, that human beings have made the natural world of mountains, lakes, trees, the moon and the sun.

Preoperational children understand the world in egocentric ways. They form their ideas of the world from their own direct experience, and from their own limited point of view. The child simply cannot understand how someone else's point of view might be different from his own, and is unable to coordinate how he sees the world with another person's perspective. Piaget considered the egocentrism of the preoperational child "as the main obstacle to the coordination of viewpoints and to cooperation." He stressed the importance of peer interaction as a means of freeing the child from the constraints of egocentrism.

A delightful aspect of the behavior of a preoperational child is the ability to engage in creative play. With this new skill of mental imagery, the progression to higher levels of thought can be seen in the child's increasing ability to represent reality through pretend play activity. The child can now pretend that a box is a table, a line of chairs is a train, and a leaf is a plate, for instance. Such imaginative play reaches a new level of abstractness when the child begins to encode experience as words. There is consistent correlation between pretend play and cognitive development and between pretend play and language development at the ages of two or three years.

With the egocentric thinking typical at this stage, children's play remains their own, even when they are playing together. This is known as parallel play. The child is aware, and even welcomes the company, of other children, but those children are not a necessary part of his particular game. A child's imagination and creativity is enhanced through play, which is a valuable component of cognitive, social, and emotional development.

Preoperational children have a clear understanding of the past and the future. They can remember a past experience and the emotions that accompanied that experience and are also able to anticipate a future event, and to anticipate possible outcomes.

Concrete operations stage (seven to 11 years) Children at this stage have developed the ability to perform mental operations, what Piaget called "interiorized action." Operations cause the child to decenter; that is, the child can now consider several attributes of an object or person at once rather than limiting concentration to a single attribute.

Mental operations such as the concepts of conservation of number, length, area, weight, and volume have been accomplished through the child's own manipulation and observation of concrete objects. Conservation means that the child has come to realize that certain attributes of an object or set of objects will remain constant even when they are made to look different. The various aspects of conservation develop sequentially throughout this stage in response to the child's continued observations and interactions with the world around her. Conservation of liquid volume, where the child can recognize a liquid is of the same quantity regardless of the shape of the glass it may be poured into, may not develop until as late as the age of twelve.

During this concrete operations stage, the child acquires the ability to think back, a concept known as reversibility. A child who has developed reversibility can literally retrace their mental and physical steps, for instance, to find an object that has been left behind. Children in the concrete operations stage can also successfully complete arithmetic operations, adding, subtracting, multiplying, and other forms of abstract thinking. Other concrete operational skills developed during this period include the classification of objects, telling time, and aligning objects systematically according to size.

However, at this stage children will continue to take life literally, so the use of satire or language metaphor is lost on them. A child at the stage of concrete operations can logically organize her experiences and understand the world from another person's perspective, but continues to live in the moment.

Formal operations (11 years to adult) Individuals who reach this stage of development now have the capacity for logical and abstract thinking and hypothetical, theoretical reasoning. They are capable of using logic to solve complex problems and can investigate a problem in a careful and systematic fashion, considering all factors that could affect an outcome. Not all children who grow into adulthood reach this stage of formal operations. Research has shown that this level of abstract thinking and theoretical reasoning may be reached by as few as 35% of adults. And not all persons who have acquired these skills of abstract thinking and hypothetical reasoning will operate from that level at all times.

The formal operations stage is characterized by an orderliness of thinking and a mastery of logical thought that allows for a more flexible kind of mental experimentation. The adolescent or young adult at this stage has learned to see the implications of his own thinking and that of others. He has constructed a value system and possesses a sense of moral judgment. In Piaget's view there are no additional mental strucures that will emerge in the individual. Development at this stage is a deepening of understanding.

Methodology

Piaget's empirical research took many forms throughout his career, depending on what aspect of cognitive development he was studying at the time. He employed techniques of careful, naturalistic observation of the child's spontaneous behavior. Sometimes this observation was without intervention; other times he introduced some form of verbal or motor stimulus to elicit a response. He attempted to follow the child's thought as he observed. Piaget and his coworkers then added experimental tasks for the child to complete. These tasks were designed in response to an idea or intuition that occurred to the observer as they followed the child's line of thought and observed behaviors. The tasks were intended to elicit pertinent and interpretable behavior that would further describe and explain the variety of intellectual structures children possess at distinct levels of development.

Piaget's earliest research began with French school boys, ages five to eight years, at the École de la rue de la Grange-aux Belles in Paris. He attempted through careful and respectful questioning to elicit information that would further reveal the workings of the curious minds of these children who first intrigued him with their patterns of wrong answers to the IQ tests he was hired to administer to them. He made systematic and detailed records of his findings as he watched and interacted with the children at play.

Piaget asked questions of the children in order to decipher the type of thinking they might be using. He called his experimental technique "the clinical method," which became his method of choice in working with children. Piaget's clinical method was similar to the diagnostic and therapeutic interviews and informal exploration he learned while working in Bleuler's psychiatric clinic in France.

The willingness Piaget showed to engage his young research subjects at their own level often brought him to his knees where he observed and engaged with them in play. With children in the preoperational stage he explored how they think about the system of rules that pass from older children to younger ones, informing their play. He played marbles with the young boys, asking questions such as, "What do you mean by rules?" and "Where do the rules come from?" and "Who makes them up?" He sought to understand the emerging sense of morality inherent in the rules by which the children played the simple game.

When Piaget returned to Switzerland to become a research psychologist at the Jean-Jacques Rousseau Institute in Geneva in 1921, he continued to observe school children and began to articulate his ideas about how children develop reasoning, language, and morality in his first series of books, including The Language and Thought of the Child, published in 1923, and The Judgment and Reasoning in the Child, published in 1924. The books brought his preliminary and revolutionary research to the attention of the world's scientific community. At this point in his career, Piaget's investigations focused on how children develop reasoning skills and the mechanisms they employ as they satisfy their curiosity and gain new knowledge.

In 1925, Piaget, together with his wife, Valentine, also a research psychologist, began the painstaking observations and detailed recording of the cognitive development of their three children, a son and two daughters, from infancy through their teenage years. The couple documented the results of their careful observations of the children. Piaget published five new books about child psychology from these studies, including the 1936 publication The Origins of Intelligence in Children.

Piaget developed research methods to serve his intent to get "to the heart of the child's cognitive structure and describe it as it really is," according to John Flavell, writing about Piaget's rationale in his book, The Developmental Psychology of Jean Piaget.

"One simply must adopt a technique, whatever its hazards and difficulties, which permits the child to move on his own intellectually, to display the cognitive orientation which is natural to him at that period in his development," Flavell wrote, explaining the rationale of Piaget's early methodology. Piaget also understood some of the dangers and difficulties in his clinical method, as he is quoted in Flavell's book:

The good experimenter must, in fact, unite two often incompatible qualities; he must know how to observe, that is to say, to let the child talk freely, without ever checking or side-tracking his utterance, and at the same time he must constantly be alert for something definitive; at every moment he must have some working hypothesis, some theory, true or false, which he is seeking to check.

As his studies in genetic epistemology continued, Piaget tried to adapt his methodology to the special problems involved in using children as subjects in perceptual experiments. Piaget employed what he and his coworkers called the clinical concentric method. In this method, according to Flavell, the experimenter presents a series of stimuli of different values and requires the subject to judge each of these stimuli with respect to some standard stimulus (greater than, less than, or equal to the standard). Piaget developed techniques to discover and demonstrate the cognitive abilities and developmental markers at each stage of the child's intellectual growth.

Examples

Three mountains task To explore the egocentric way of thinking so typical in the preoperational stage, Piaget used what he called the three mountains task. He positioned children in front of a three dimensional model of a mountain range, then seated himself to the side. He then presented the child with a set of four photographs of the mountains as displayed in the papier-mâché model and asked them to pick out the view of the mountains that they believed the professor could see from his seat. Consistently, children in the preoperations stage will choose the picture depicting the view from their own perspective and not that of Piaget. Children who have progressed into the concrete operations stage will consistently choose the photograph taken from the experimenter's point of view.

Conservation studies Piaget tested for the concept of conservation of liquid volume with differently shaped glasses. He poured equal amounts of liquid into glasses of a different height and width. The child in the preoperational stage, who still relies on perceptual information rather than logic to form their opinions, will consistently insist that the liquid in a thin, tall glass holds more than an equal amount of liquid poured into a wide, shallow bowl. A child demonstrates a grasp of the concept of conservation of liquid when they can recognize that both vessels, regardless of shape, hold the same amount of liquid. This skill is developed in the concrete operations stage.

Piaget tested for the concept of conservation of number with coins. He placed two sets of coins on a table in parallel lines. Each line contained the same number of coins, but in one line Piaget spread the coins farther apart than in the other. When asked which line contained the most coins, children younger than seven years old consistently choose the line in which the coins are spread farther apart. They will persist in this belief, despite being shown, by stacking the coins, that each set contains an equal number. A child demonstrates a grasp of the concept of conservation of number when they can recognize that each line of coins contains an equal number, no matter how they are arranged.

Piaget used clay to demonstrate two concepts, that of conservation of substance and reversibility, two developmental tasks of the concrete operational stage. In this experiment he first obtains the child's agreement that two balls of soft clay are of equal size. Then he rolled one ball of clay into a long cylinder or sausage-like shape. Placing the two masses of clay side by side, the ball shape alongside the cylinder shape, he asks the child again if they are of equal quantity. If the child has acquired the skill of conservation of substance, she can now answer correctly what she could not grasp earlier. She now comprehends that the substance is conserved regardless of the changes in shape it may undergo. This recognition also is evidence of the child's grasp of the concept of reversibility. She has acquired the skill to follow in her mind the changing form and shape of the clay and can then think back to that same clay when it was a round ball and recognize it has having the same quantity.

Questions and answers Piaget posed simple questions in his clinical interview style to determine if a child had passed beyond the stage of seeing all objects as animate, or alive, a concept called animism. He questioned children in the preoperational stage to determine their perceptions of the aliveness of objects. He wanted to determine the types of objects the child would our would not classify as alive.

"Does the sun know it gives light?" he asked, or "When I pull off this button will it feel it?" The children's answers varied throughout the developmental stage. The number and type of objects they endowed with consciousness declined with the age of the child and the increased experience with the outside world.

Piaget questioned adolescents to determine if they had made the transition from the concrete operational stage to the stage of formal operations with its capacity for hypothetical deductive reasoning. He asked why a pendulum swings faster or slower. Individuals who have achieved the formal operations stage will test the pendulum by systematic variations of one factor at a time, holding the others as a constant, to determine each factor's effect on the pendulum's motion. Adolescents who have not yet reached the formal operations stage will vary more than one factor as they struggle to find a solution to the question, making an accurate conclusion unlikely.

Through his interactive observations and empirical research, Piaget demonstrated that the developing intellect of the child is self-motivated and energized by the need to satisfy curiosity. To Piaget, thought is a process in continual transformation and reorganization. Children construct their own knowledge, Piaget said, through their action in, and on, the world. Like Maria Montessori, whom Piaget studied, Piaget believed that when children are allowed to act on the environment, performing the tasks themselves rather than merely being told how things work, they are better able to construct a more comprehensive scheme as their thinking evolves from the concrete to the abstract.

Philosophy: The constructivist's vision

"I am a constructivist." Piaget wrote. "I think that knowledge is a matter of constant, new construction, by its interaction with reality and that it is not preformed. There is a continuous creativity." As a constructivist, part of the philosophical school of structuralism, Piaget understood learning as an active process in which new ideas or concepts are constructed based on current or past knowledge. The individual selects and transforms information, constructs hypotheses, and makes decisions, relying on a cognitive structure that provides meaning and organization to the experiences. For Piaget, constructivism means that an individual always and only learns through constructing. He maintained that biological maturation provides the range of potential for cognitive growth, but developing the ability to perform operations requires an active, supportive environment and social interactions that encourage children to construct their own knowledge. Piaget also understood that there is no beginning and no end to the construction of knowledge. The individual is continuously acquiring and modifying skills.

Michael J. Mahoney, writing on the Constructivism site on the World Wide Web has outlined five basic themes that are found throughout the diversity of theories that express constructivism. These are active agency, order, self, social-symbolic relatedness, and lifespan development.

"Jean Piaget developed a model of cognitive development in which balance was central. Piaget described knowing as a quest for a dynamic balance between what is familiar and what is novel," Mahoney writes, "We organize our worlds by organizing ourselves. This theme of developmental self organization pervades constructive views of human experience."

The methods of constructivism that Piaget advanced in his theories of genetic epistemology continue to inform and challenge educational technology today. Though Piaget did not see himself as an educator, he did have some advice for teachers. He told interviewer Richard Evans that he hoped his work would influence teachers to begin "educating for an experimental frame of mind." It is important, he said, that teachers present children with materials and situations and occasions that allow them to move forward. "It is not a matter of just allowing children to do anything. It is a matter of presenting to the child situations which offer new problems, problems that follow on from one another. You need a mixture of direction and freedom."

HISTORICAL CONTEXT

Twentieth-century psychological theories

Piaget's professional life spanned a tumultuous six decades of the mid twentieth century, during a time of rapid growth and development in the scientific disciplines. Piaget read widely in the fields of philosophy and psychology. He was influenced in his reading by the ideas of Immanuel Kant (1724–1804), whose concept of categories was a precedent for later psychological theories using terms such as "constructs" and "schemes." He was also influenced by Henri Bergson (1859–1941), whose book Creative Evolution changed Piaget's thinking about the nature of life. Other philosophers and thinkers in the nineteenth century also influenced Piaget's thinking, including Charles Darwin, John Dewey, Emil Durkheim, and James Mark Baldwin, from whom Piaget borrowed the phrase genetic epistemology to describe his theory of the acquisition of knowledge.

Piaget was fortunate to meet many of the influential European psychologists of his day. He studied with Carl Jung, shared the podium with Sigmund Freud at the 1922 Congress of Psychoanalysis in Berlin, had conversations with Albert Einstein, worked as a research associate at the Simon-Binet laboratory in Paris, knew Maria Montessori, and met Robert Oppenheimer and the Gestalt psychologists Max Wertheimer and Wolfgang Köhler.

Much of the seminal writing of the era, particularly that of the early Gestalt thinkers and the constructivist theories of the Russian psychologist Lev Vygotsky, was unavailable to Piaget early in his career because of language barriers. His own later work was not made available in translation in the United States until well after World War II. Not one of his books was translated into English between 1932 and 1950. This was due, in part, to the prevailing influences of the behavioral psychologists in the United States, whose stimulus-response views Piaget did not embrace. France was under German occupation during parts of World War II, and this further restricted the free flow of ideas within the global scientific community. During the occupation of France in 1942, Piaget lectured at the College of France. He later remarked that his invitation to lecture during the German occupation enabled him to bring to his French colleagues, "testimony of the unshakable affection of their friends from the outside."

Piaget shared the point of view of the constructivists, and, with some differences in approach, engaged in the study of cognitive development in ways similar to John Dewey, Lev Vygotsky, Jerome Bruner, Maria Montessori, and others. These psychologists believed that children actively construct knowledge and that this construction happens within a social context. Piaget also felt a kinship in his work with the theories of Edward Tolman (1886–1959), whose work attempted a synthesis of Gestalt psychology and behaviorism, and with other Gestalt psychologists and their ideas regarding the "totalities" of cognitive structure.

The dramatic shift in psychology from behaviorism to cognitivism that began in the early part of the twentieth century was greatly influenced by the work of one of Piaget's American contemporaries, Jerome Bruner. Bruner was instrumental in bringing Piaget to the United States at a time when psychologists and educators were losing confidence in the field of behaviorism, which had dominated American educational psychology for decades. Behaviorism was starting to be viewed as far too limited with its reduction of learning to a reactive stimulus-response relationship. Piaget had a different view of learning than behaviorist B.F. Skinner. To Piaget, learning is first of all an active process, one that is linked to specific stages of development and includes both external and internal, self-regulating reinforcements.

Piaget traveled to the United States on numerous occasions to lecture on his theories and to accept honorary degrees from prestigious universities. After World War II his books were finally translated and available to American scholars, further encouraging the growth of the emerging science of cognitive development that increasingly attracted students and psychologists to his Geneva research laboratories. Piaget was a man whose time had come.

CRITICAL RESPONSE

Contributions and shortcomings

Extensive criticisms of Piaget's work have been voiced in the scientific community throughout the 60 years that he labored to develop and articulate his theory of genetic epistemology and in the decades since his death in 1980. Despite the shortcomings that many critics point out in Piaget's work, few have disputed the considerable contributions of his theory to scientific thought, or his role as one of the most influential research psychologists of the twentieth century. Piaget is respected, even by his critics, for transforming how we think about children. His foundational work continues to influence educational theory throughout the world. Piaget's work has been characterized as the starting point for many different strands of theoretical investigation in the area of education and developmental psychology.

General criticisms of Piaget's theory include:

• complexity of his writing style
• flawed methodology
• qualitative rather than quantitative interpretation of findings
• rigidity of developmental stages
• failure to consider variables of culture, race, gender, etc.
• lack of longitudinal or life-span studies
• underestimation of the intelligence of young children
• the fact that not everyone in every culture reaches the formal operations stage
• possibility of development beyond formal operations

Piaget's theoretical writings total as many as 120,000 pages, according to Jacques Voneche, Professor of Child and Adolescent Psychology at The University of Geneva and Director of Jean Piaget Archives. Piaget wrote in an abstract way, according to Professor John Flavell, who provided the first English language summary of Piaget's theory in his definitive book The Developmental Psychology of Jean Piaget. Most of Piaget's publications were from largely unedited materials, delivered to the printer in handwritten drafts. This extensive body of writing is difficult to assimilate, in part because of the complexities of his writing style. He uses complicated sentence structures and introduces new terms and concepts, while redefining the meaning of other familiar terms. According to N. R. Carlson and W. Buskist, writing in the 1997 edition of Psychology: the Science of Behavior, "One criticism leveled at Piaget is that he did not always define his terms operationally. Consequently, it is difficult for others to interpret the significance of his generalizations."

Piaget's original work is in French and not all translations interpret his concepts consistently. Professor Flavell used the term "opaqueness" with regard to Piaget's writing. The lack of clarity, or "communicative inadequacy," as Flavell called it, has created a barrier to the understanding of this important body of work. Flavell believes that this is a most unfortunate handicap in a cognitive theory that contributed so significantly to a revolution of thought in twentieth century psychology.

Much of the early research with regard to Piaget's theories reported in Flavell's 1963 book was concerned with replication and validation of his theories. Piaget left a lot of room for concern with what Flavell called a "habitual failure to give a clear and full account of precisely what he did in the experiment." Still another criticism is with regard to Piaget's analysis of his data. He did not provide a sufficient quantitative evaluation of his findings. Without statistical analysis of the results, the findings are difficult to interpret or compare with other studies. Subsequent researchers, uncertain about the empirical basis for his experimental conclusions, focused on replication and validation, rather than on elaboration of the work that Piaget began. Piaget "simply did not conduct and report his research in such a way as to make a very convincing case," Flavell explained. Nonetheless, these early researchers, for the most part, were able to validate most of the essentials of Piaget's conclusions.

Flavell's criticism, and that of others, extends to Piaget's theoretical conclusions, particularly with regard to the stages of cognitive development. Flavell contends that Piaget has "attributed too much system and structure to the child's thought." He proposes theoretical changes that reflect a "somewhat looser clustering of operations." Flavell believed such an adjustment to Piaget's stage structure might free it from what he called its "rigidity and maladaptability."

Annette Karmiloff-Smith, professor of neurocognitive development at the Institute of Child Health in London began her career as a member of the International Centre for Genetic Epistemology run by Jean Piaget. From 1972 to 1980 she worked on normal cognitive development across various areas of cognition, publishing several research papers with Barbel Inhelder. Professor Karmiloff-Smith has recently criticized Piaget's stage theory of cognitive development, which she considers "almost obsolete." Speaking on a BBC radio interview in 2003, she commented, "there are more structures to the brain than Piaget ever imagined."

Another major criticism of Piaget concerns the empirical aspects of his work. Many believe that his research methodology was flawed. Piaget relied on observation, the clinical interview, and the administration of certain tasks at each developmental stage to formulate his theory. In this way he hoped to discover and delineate the characteristic behaviors and perceptions that determine cognitive growth. The unstructured clinical interview style that Piaget favored, using a question and answer format to elicit information about the child's thinking, has been criticized by many who study his work. British researcher J. G. Wallace believed that the "ambiguity of verbal response" may have been used by Piaget "to derive support for his preconception."

Other critics have expressed concern with the limited samples Piaget used to develop his broad assertions about the progress of all children. Critics also point to Piaget's lack of cross-cultural subjects in his investigations, and the fact that he did not consider other variables of social factor, such as personality, race, gender, and nationality, nor did his investigations follow individuals throughout their lifespan. Piaget's first five books were largely based on detailed observations of his own three children from infancy through their teen years. Though Piaget considered these books as only preliminary, they were widely read and brought him early fame. Young researchers from throughout the world came to work with him in his Geneva laboratory.

Lev Vygotsky

One of the earliest and by some accounts best of Piaget's critics was the Russian scientist Lev Vygotsky. He was born in 1896, the same year as Piaget, and like Piaget became prominent while still a young man. Unlike Piaget, Vygotsky died early, of tuberculosis at the age of 34. Vygotsky was a linguist and educator interested in the origins and mechanisms of knowledge. In the 10 years prior to his death, Vygotsky set down a comprehensive theory of cognitive development, providing many alternatives to Piaget's work. Though Vygotsky had access to Piaget's writings, the language barrier kept Piaget from reading Vygotsky's criticisms until decades after the Soviet researcher died.

There are many similarities in the two men's views. Piaget pointed to biological development as the process that impels movement from one stage to the next. Vygotsky agreed that individuals pass through distinct stages of development, but stressed the importance of historical and cultural forces on the individuals' ability to reach or move through each developmental stage. This cultural context of learning is an important element in Vygotsky's theory. Like Piaget, he understood that experience with physical objects is a necessary element in cognitive growth, but Vygotsky also noted the important part played by the use of tools. Both theorists recognized the child as an active agent who constructs his own reality, but Vygotsky was an educator who understood learning as a cooperative venture of both teacher and child. Learning, to Vygotsky, is coconstructed. He put forth the concept of a "zone of proximal development," the gap existing between the limit of what a child can learn acting alone and the extent to which a child can learn with the help of an adult or other more capable peers.

As a linguist Vygotsky considered language as the basis for cognitive development. He paid particular attention to the role of gestures in language acquisition. Like Piaget, Vygotsky rejected the mechanistic theories of behaviorism. He believed that it was language that helps human beings break the stimulus-response cycle and gain control over their environment. The child's earliest attempts at speech, often indecipherable to adults, nonetheless assists the developing child with memory, problem solving, and even in making plans for the future. Piaget viewed the child's self-talk as primarily an indication of the cognitive limitation he called "egocentric." Vygotsky, on the other hand, believed that such child's talk reflects the formation of a plan that would modify the child's subsequent behaviors.

Discovery learning at any stage

Jerome Bruner, a Harvard professor and Director of the Center for Cognitive Studies, developed a stage theory of cognitive growth that differs from Piaget with regard to the impact of environmental and experiential factors on the developing child. Bruner's theories were influenced by Vygotsky, particularly with regard to his emphasis on the importance of the social and political environment. Bruner understood that the process of constructing knowledge of the world is not accomplished in isolation. He emphasizes the importance of the social context within which learning takes place. Bruner helped to define the concept of discovery learning, defined by J. Ormrod as "an approach to instruction thorough which students interact with their environment by exploring and manipulating objects, wrestling with questions and controversies, or performing experiments."

Bruner's sociocognitive stage theory of learning is based on the child's reciprocal interaction with the teacher. He has departed from Piaget's idea of developmental readiness for learning with the hypothesis "that any subject can be taught effectively in some intellectually honest form to any child at any stage of development."

Making "human sense"

Margaret Donaldson of Edinburgh University put forth yet another criticism of Piaget's method, claiming the he used unfamiliar concepts and objects to test the cognitive development of the children he worked with, and that this led to the misinterpretation of their cognitive skill levels. The tasks proposed to the child and the language used to describe them need to make "human sense," she said. Donaldson, a child development psychologist, visited Piaget's research center in Geneva where she attended seminars and observed actual testing. She has criticized what she described as "contrived experimental work," that provides the experimenter with only one view of the child. Donaldson and others tested Piaget's theories on preschool children and concluded that the reason these children were unable to perform Piaget's tasks successfully was primarily due to their difficulties understanding the questions being asked of them, rather than a lack of logical skills or the cognitive limitations of what Piaget called "egocentric" behavior. Donaldson took issue with Piaget's findings, particularly with regard to his three mountains task, in her 1978 book Children's Minds. When the researcher uses more familiar items and language, children may perform beyond Piaget's stages. Young children are capable of much more than Piaget ever gave them credit, she contends. There is now a significant theoretical work that suggests children perform beyond Piaget's levels when using more familiar testing tools.

Out of sight, not out of mind

Renee Baillargeon, professor of psychology at the University of Illinois at Urbana-Champaign, has tested Piaget's concept of object permanence, the out of sight, out of mind perception that Piaget considered a cognitive limitation of the early sensorimotor stage. In a 1997 study Baillargeon and others demonstrated that infants as young as three and one half months of age can remember a toy (a Mr. Potato Head) after it has been hidden from sight.

In two later experiments published in 2003, Baillargeon and others tested four-month-old infants in what she termed "violation of expectation," or VOE tasks.

The infants still gave evidence that they could represent and reason about hidden objects: they were surprised, as indicated by greater attention, when a wide object became fully hidden behind a narrow occluder (Experiment 1) or inside a narrow container (Experiment 2).

Unlike previous tests, in these experiments the infants were not first given "habituation or familiarization trials," but only a single test trial. Baillargeon's research provides additional support for the conclusion in her previous studies that "young infants possess expectations about hidden objects." Her experiments have shown that very young infants already are learning concepts of object permanence relative to visible and hidden objects before Piaget believed they were developmentally able to do so.

Spatial learning

Janellen Huttenlocher, a professor of Psychology at the University of Chicago, and the 2002 recipient of the G. Stanley Hall Award for Distinguished Contribution to Developmental Psychology, is a leading researcher on spatial learning. Her studies have shown that children acquire an understanding of spatial information much earlier than Piaget proposed. Infants as young as six months, she said, are able to use the inborn ability of dead reckoning skills to understand the location of objects around them. By the time they reach their first birthday, children can comprehend distance enough to locate hidden objects. Huttenlocher suggests that growth in spatial understanding develops through a combination of the child's innate abilities, a process of trial and error interaction with the environment, and the child's cultural environment. She suggests an "interactionist" approach to spatial development that will incorporate and integrate the insights of Piaget, who believed infants develop knowledge of space through trial and error experience; the nativists' approach that holds that the basic intelligence of spatial understanding is innate; and Vygotsky's emphasis on the cultural transmission of spatial skills.

Huttenlocher is investigating how teachers can influence the development of the intellectual skill of spatial understanding, and with other researchers is using computer games to investigate students' navigational skills and their ability to perform "mental rotation" tasks. She is also developing computer software to help students sketch maps as a way of further developing a spatially mature intellect.

A higher law

Children define morality individually, according to Piaget, and this occurs in the process of their struggles to arrive at fair solutions. He theorized that the way children learn respect for rules is by playing rule-bound games. Mary Elizabeth Murray, of the Department of Psychology at the University of Illinois at Chicago, acknowledged that "Jean Piaget is among the first psychologists whose work remains directly relevant to contemporary theories of moral development."

Lawrence Kohlberg (1927–1987) studied with Jean Piaget. He did most of his later research at Harvard University, where he worked to modify and elaborate on Piaget's work, particularly with regard to the issues of moral development. Kohlberg extended the development of moral judgment beyond the ages studied by Piaget, according to psychologist Mary Murray, "and laid the groundwork for the current debate within psychology on moral development." He determined that the process of attaining moral maturity was a longer and more gradual one than Piaget first theorized.

Kohlberg investigated 84 schoolboys in a longitudinal study that followed the boys development over a period of 20 years. Kohlberg concluded that an even more advanced stage of cognitive development, beyond Piaget's formal operations stage, may be reached by some adolescents. In this advanced stage, the individual will perceive the rule of law as valid only if it serves a purpose greater than oneself or those in one's circle of care. For a law to be obeyed it must also serve universal moral or religious values. Kohlberg found that only 5% of the student population he studied had attained this stage of moral understanding.

Kohlberg's six stages of moral development include:

• Stage one: The punishment and obedience orientation. The physical consequences of action determine its goodness or badness regardless of the human meaning or value of these consequences.
• Stage two: The instrumental relativist orientation. Right action consists of what instrumentally satisfies one's own needs and occasionally the needs of others.
• Stage three: The interpersonal concordance or "good boy-nice girl" orientation. Good behavior is what pleases or helps others and is approved by them.
• Stage four: The "law and order" orientation. The individual is oriented toward authority, fixed rules, and the maintenance of the social order.
• Stage five: The social-contract legalistic orientation (generally with utilitarian overtones). Right action tends to be defined in terms of general individual rights and standards that have been critically examined and agreed upon by the whole society.
• Stage six: The universal ethical-principle orientation. Right is defined by the decision of conscience in accord with self-chosen ethical principles that appeal to logical comprehensiveness, universality, and consistency.

Carol Gilligan, writing in her 1982 book In A Different Voice, criticizes both Piaget and Kohlberg's work in the area of moral development as being biased against girls and women. She is concerned with Piaget's "bias that leads him to equate male development with child development," particularly in his studies of childhood games, and with Kohlberg's bias in studying only boys in his longitudinal investigations of moral development leading to his six-stage theory.

Piaget observed that young girls play differently from boys. Boys are more concerned with rules, and girls with relationships, Gilligan says. If the study of moral development would begin from the lives of women, Gilligan writes, the moral problems would be characterized as those "arising from conflicting responsibilities rather than from competing rights." Such moral questions would require for solution "a mode of thinking that is contextual and narrative rather than formal and abstract."

In contrast to Gilligan's views, Mary Elizabeth Murray contends that "the preponderance of evidence is that both males and females reason based on justice and care."

Many thousands of studies

One of the marks of a good theory is in the amount of research it stimulates, and within this criteria, Piaget's theory is truly great. Many thousands of research studies throughout the world have been published in scientific journals regarding Jean Piaget's theories of genetic epistemology. In 1974 an eight-volume set of compilation and commentary referenced over 3,500 studies. In the 30 years since those volumes appeared, Piagetian research has continued, particularly in the area of the application and utility of genetic epistemology to the fields of early childhood education, including the acquisition of morality. A vast body of research has arisen to test Piaget's theories and confirm or refute his claims.

The beginning student of Piaget has a daunting task in assimilating the complex theory of genetic epistemology. It is an additional challenge to distinguish the most relevant studies from among the thousands that have been done, and to find those investigators whose critical work will either validate, refute, or extend Piaget's findings in a way that will further the understanding of the origin and nature of knowledge, and not confound the search.

THEORIES IN ACTION

In a 1970 interview with Elizabeth Hall in Psychology Today, Jean Piaget addressed the question of the practical applications of his theory of genetic epistemology.

The danger to psychologists lies in practical applications. Too often psychologists make practical applications before they know what they are applying. We must always keep a place for fundamental research and beware of practical applications when we do not know the foundation of our theories.

Piaget's caution is well taken. Since the late 1950s, when his writings were translated for readers in the United States, his influential ideas have been applied widely and survived extensive criticism. Piaget's theory of genetic epistemology changed the educational philosophy of the mid-twentieth century by providing a scientific basis for understanding how learning happens. His comprehensive theory remains vital today.

Decades after his death, Piaget's revolutionary insights and innovative theories continue to stimulate volumes of research and academic discussion published in scientific journals throughout the world. His interdisciplinary approach to the discovery of the nature and origin of knowledge informs numerous fields of scientific thought today, from educational psychology and learning theory to computer technology and artificial intelligence. Parents, educators, child-care workers, pediatricians, child psychologists, and software designers all benefit from the work of Piaget and his many collaborators.

In the classroom

Piaget's influence has been extensive in the field of education, particularly in the areas of teaching practice and curriculum design. Piaget never considered himself to be an educator and had little to say regarding the practice of education. Nonetheless, this Swiss innovator's many insights into how children learn have been studied and applied throughout the educational system. Piaget helped educators understand the importance of novelty and active participation in learning, as well as the value of collaborative learning in a sensory rich environment. Piaget's theory offers an understanding of students' developmental readiness and insight into ways a teacher can facilitate a child's growth to more complex cognitive levels. Both are vital components to developing a child-centered, child-directed curriculum. Piaget's findings about the distinctions between concrete and abstract thinking, and the general ages at which these skills predominate, has had tremendous influence on when and how science and mathematics are presented to children.

Teachers who understand Piaget know that the very young student learns through trial and error and needs access to a diversity of objects for manipulation. As the child becomes older and has progressed into the concrete-operational stage, a teacher influenced by Piaget's theories will know to present the child with problems of classification, ordering, location, and conservation. Teachers facilitate cognitive development by providing activities that engage learners, challenge their existing beliefs, and stimulate adaptation to new levels of understanding. Teachers applying Piaget's insights will make the learning environment interesting with support for exploratory activity and peer interactions, and keep the focus on projects that require solutions to real-life, practical problems.

Jean Piaget believed in the power of knowledge and the importance of children learning to think for themselves, as architects of their own destinies.

If we desire to form individuals capable of inventive thought and of helping the society of tomorrow to achieve progress, then it is clear that an education which is an active discovery of reality is superior to one that consists merely in providing the young with ready-made wills to will with and ready-made truths to know with.

Research Marie Anne Suizzo, writing in the journal Child Development in 2000, cited a 1996 study by researchers Robbie Case and Yukari Okamoto that explored the cross-cultural attainment of Piaget's formal operations stage of abstract reasoning. They administered Piagetian tasks to determine the developmental stage of individuals tested and concluded that "children, and even adults who live in societies where the base ten number system is not in use, or where formal schooling is not available to all, do not usually attain the level of formal operational thought normally reached by adults in industrial societies."

Teachers who understand Piaget's work are aware that direct instruction may fail if it is not appropriate to the stage of the child's cognitive capacity, and that not all persons will attain Piaget's stage of formal operations.

Cyberspace

Educators have realized that for students to be successful in the twenty-first century, they need to acquire the skills to become lifelong learners. Lifelong learning is a concept with which Piaget would have been comfortable, though he may not have anticipated the tremendous advances in technology that are bringing a revolution to how students acquire information and interact with the world.

"Twenty-first century children can access more information at greater speed than any generation in history," says Wilborn Hampton, an editor at the New York Times, writing about children, television, and the Internet. He cautions that teachers and parents must teach this "fledgling generation of the cyberspace age to look beyond the first answer they get." His caution, like Piaget's regarding the application of his theories, is worth remembering in this age of artificial intelligence and worldwide connectivity through the Internet. The Internet is a goldmine of information and resources on virtually any topic imaginable. Specialized search engines assist in computer assisted learning and retrieval of information, and the interactive multimedia encyclopedias and CD-ROM technology can provide a rich and stimulating learning experience with opportunity for both collaborative and individual learning. Tools such as word processors, spreadsheets, databases, and drawing programs enable a student to publish the results of their explorations, reaching beyond the classroom to a potentially vast number of learners with whom they can share and discuss their discoveries.

Computer-supported collaborative learning and the Internet have extended Piaget's ideas of lifelong learning in ways even this creative genius many never have imagined. "ThinkQuest," is an international competition where student teams engage in collaborative, project-based learning to create educational websites. The winning entries received from students throughout the world form the ThinkQuest online library. Computer programs such as "Cybrid" CDs add the expert help of cyberspace teachers and experts who are available at the click of a mouse.

One of Piaget's collaborators, Jean Papret, now a professor of education and media technology at the MIT Media Laboratory, called Piaget a "towering figure and a major theorist of how the mind works." Speaking at a symposium on computers in education at MIT in 2002, Papert said, "the essence of Piaget was how much learning occurs without being planned or organized by teachers or schools." Papret has focused his study on how individuals learn to learn. His interest has been in the tools, media, and context of learning. Papret shares Piaget's view that the child actively constructs knowledge by interaction with her world, and he has taken his understanding of cognitive development into the realm of artificial intelligence. Papret says he started out in the field of artificial intelligence with the questions, "Can we make a machine to rival human intelligence? Can we make a machine so we can understand intelligence in general?"

Papret is a constructionist, who shares Piaget's constructivist view, but adds the insight that learning is enhanced in a context where the learner finds a way to share those ideas with the wider community. Papret believes that it is important to make ideas tangible, to shape and sharpen them by making them public in some way. He studied how knowledge is formed, transformed, processed, and expressed through different media. Papret was involved in early research into artificial intelligence. Now, he says, "I see my contribution as helping to birth a perspective on learning: not 'education' or 'school,' but a field that is bigger and essentially different from anything that has existed."

A scientific society formed in 1979, the American Association for Artificial Intelligence (AAAI), is "devoted to advancing the scientific understanding of the mechanisms underlying thought and intelligent behavior and their embodiment in machines." This seems to echo Piaget's genetic epistemology with a quest for what might be called mechanistic epistemology. The study of artificial intelligence seems to be asking some the same questions Piaget posed to children.

David Wood, writing in his book, How Children Think and Learn notes that "Communication between man and machine and skillful control of complex systems demands designs that do not overtax or exceed people's abilities to attend to, monitor, and react to the behavior of the system under control." He sees the necessity for application of cognitive development principles to systems design. "Any system that provides too much critical information at any one moment or which leaves the human operator with too little time to interpret and react to it makes inhuman demands and cannot be controlled."

Case study

Piaget recognized the importance of play, and the necessity for children to handle and explore objects to find out how they work. Play is the fundamental way children construct their theories about how the world works.Over the years since Piaget's innovative research with children, toys have changed. In the 1980s computer toys that dramatically altered the way children play began to appear on the market.

Sherry Turkle, a professor in the program in science, technology, and society at MIT, has studied the relationship between children and their electronic pets and computer toys over three generations. She has observed in her studies the emergence of a new consciousness among children who play with computer toys. "Cyborg consciousness," Turkle says, is "a tendency to see computer systems as 'sort of' alive, to fluidly cycle through various explanatory concepts, and to willingly transgress boundaries."

In her early research Turkle observed that "children described the life-like status of machines in terms of cognitive capacities (the toys could 'know' things, 'solve' puzzles)." But in her research with a later generation of computer toys, the Virtual pets and digital dolls of the 1990s, Turkle sees a blurring of boundaries with what children consider to be alive. These toys require an interaction that necessitates some form of nurturance from the child. When children play with these new computerized toys, Turkle's observations show, they seek a feeling of mutual recognition. They want to know how to make the toy happy. The furry and cuddly electronic pets, called Furbies, "add the dimensions of human-like conversation and tender companionship to the mix," Turkle says. The children consider Furbies as "sort of alive." This belief, Turkle says, "reflects their emotional attachments to the toys and their fantasies that the Furby might be emotionally attached to them."

These children of the computer age will, perhaps, construct quite a different reality than the Paris school boys who Piaget first sat down with to observe their simple game of marbles. Watching children at play led him to an understanding of how children's rules of fair play relate to the development of a moral consciousness. Researchers are just beginning to ask how these new interactive toys, embedded with artificial intelligence and feigned affection, will affect the psychological processes of twenty-first century children and the evolution of their world view.

Moral and ethical applications

Piaget's work with children led him to investigate the realm of moral reasoning. His initial work has inspired other researchers to pursue the questions of moral and ethical judgement with Piagetian theory as a starting point.

Research In a 2000 study titled "Older isn't wiser in moral reasoning," reported in Science News, psychologists Lakshmi Raman and Gerald Winder of Ohio State University tested Piaget's findings on the evolution of moral reasoning, particularly with regard to the idea of immanent, or inherent, justice, the "what goes around, comes around," notion. In their cross-cultural study the researchers presented the students with the story of a robber who contracts a mysterious deadly disease. They asked the students if they believed that the reason the robber became ill was because he was bad. They posed the question to sixth grade students and college students in both the United States and India. The results surprised them. Contrary to what Piaget's theory would suggest, it was the college students who agreed most often that the robber became ill because he was bad, an expression of the idea of immanent justice that, according to Piaget's findings, they should have long ago outgrown. The researchers concluded that even though the sixth grade children may understand the biological basis of illness, over time they will become socialized into acceptance of the "irrational idea of immanent justice."

CHRONOLOGY

1896: Jean Piaget born in Neuchatel, Switzerland.

1906: Publishes first article in local journal.

1918: Receives Ph.D. in Natural Sciences, University of Neuchatel, as Zoologist; He attends the University of Zurich for postgraduate studies. He works in Eugen Bleuler's psychiatric clinic and develops his technique of the clinical interview.

1919: Works as research associate in Simon-Binet experimental psychology laboratory administering British IQ tests to Paris school boys.

1921: Appointed research director of the Institut Jean-Jacques Rousseau in Geneva, and publishes article in the Archives de Psychologie stating that logic is not innate but develops over time through interactive processes of self-regulation.

1923: Marries psychologist and former student Valentine Chatenay and publishes The Language and Thought of the Child. Four more books follow bringing him worldwide fame before the age of 30.

1925: Returns to Neuchatel University. Daughter Jacqueline is born and the Piaget's begin the study of the intellectual development of their three children from infancy through their teenage years.

1928: Albert Einstein and Piaget meet. Einstein suggests that Piaget study the origins in children of the notions of time and simultaneity.

1929: Teaches the history of scientific thought at the University of Geneva until 1939. Begins thirty-five year tenure as director of the International Bureau of Education in Geneva.

1936: Publishes The Origins of Intelligence in Children based on his observations of his three children.

1940: Appointed Chair of Experimental Psychology, University of Geneva (until 1971).

1942: Lectures at the College of France during Nazi occupation. Lectures complied into The Psychology of Intelligence published in 1963.

1950: Publishes his three volume book, Introduction a l'Epistemologie Genetique.

1955: Jean Piaget's International Center for Genetic Epistemology opens at the University of Geneva.

1966: Piaget publishes The Psychology of the Child with Barbel Inhelder.

1969: Piaget is awarded distinguished Scientific Contribution Award by the American Psychological Association. He is the first European to receive the award.

1980: Jean Piaget dies at the age of 84 in Geneva, Switzerland.

In 1988, authors Iordanis Kavathatzopoulos and Georgios Rigas published a study in the journal of Educational and Psychological Measurement in which they sought to describe how individual politicians solve moral problems. They used Piaget's theory as a frame for development of a measurement device they called the Ethical Competence Questionnaire-Political (ECQ-P), composed of real-life ethical dilemmas from the political arena.

"The ECQ-P is an attempt to assess ethical function independent of moral, ideological, and political content," the researchers explained. The questionnaire focused solely on cognitive processes. According to the researchers, Politicians, as well as every decision maker, need a capacity to cope with moral conflicts that arise in their ordinary activities; that is, they need high ethical competence. This competence means that the individual must have:

• "high ethical awareness, the ability to anticipate ethical problems in real life and to perceive them in time
• the cognitive skill to analyze and solve them in an optimal way
• the capability to discuss and handle moral problems at group and organization levels and, together with significant others, formulate ethical principles and guidelines
• the power to argue convincingly for preferred actions or decisions made
• the strength to implement controversial decisions"

According to the authors, the results of the study demonstrated "that it is possible to construct a Piagetian paper-and-pencil questionnaire for the assessment of ethical autonomy in the domain of politics that can produce reliable results." Such research builds on Piaget's earliest work expressed in his 1932 book, The Moral Judgment of the Child, and sheds further light on the importance of moral consciousness development as an adaptive cognitive mechanism.

LeoNora M. Chen and Younghee Kim, writing in the Roeper Review in 1999, have articulated the value of Piaget's work to provide further understanding of the gifted child. Though Piaget was primarily concerned with universal child development, they note, his work is a useful foundation to the study of the gifted child. According to Chen and Kim, research in the late 1960s and middle 1980s demonstrated that gifted children move more quickly through each of Piaget's development stages. The intellectually gifted child, like the high-powered computer systems of today, is a pattern seeker. The gifted child moves toward construction of general principles that apply to all circumstances based on feedback from a few encounters. They grasp the big picture more readily than less intellectually gifted children.

Piaget concluded in The Psychology of the Child,

Child psychology enables us to follow their step-by-step evolution, not in the abstract, but in the lived and living dialectic of subjects who are faced, in each generation, with endlessly recurring problems and who sometimes arrive at solutions that are slightly better than those of previous generations.

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Further readings

Chapman, M. Constructive Evolution: Origins and Development of Piaget's Thought. Cambridge University Press, 1988.

DeLisi, R. and Golbeck, S. "Implications of Piagetian theory for peer learning," (3-37). In A. O'Donnell & A. King (Eds.) Cognitive Perspectives on Peer Learning. Mahwah, NJ: Lawrence Erlbaum Associates, 1999.

Evans, Richard L. Jean Piaget: The Man and His Ideas. Trans. by Eleanor Duckworth. New York: E. P. Dutton and Co., Inc., 1973.

Flavell, John H. The Developmental Psychology of Jean Piaget. Princeton, NJ : D. Van Nostrand Co., 1963.

Furth, Hans G. and Harry Wachs. Thinking Goes to School: Piaget's Theory in Practice. New York: Oxford University Press, 1974.

Gallagher, Jeanette McCarthy, and D. Kim Reid. The Learning Theory of Piaget and Inhelder. Monterey, CA: Brooks/Cole Pub. Co., 1981.

Gruber, H. E., and J. Vonèche. The Essential Piaget. Northvale, NJ: Aronson, 1995.

Jean Piaget Society. Society for the Study of Knowledge and Development. "Resources for Students." http://www.piaget.org/students.html.

Lee, K. Childhood Cognitive Development: The Essential Readings. Malden, MA: Blackwell, 2000.

Meadows, S. The Child as Thinker: The Development and Acquisition of Cognition in Childhood. London; New York: Routledge, 1993.

Mooney, Carol Garhart, Theories of Childhood: an Introduction to Dewey, Montessori, Erickson, Piaget and Vygotsky. St. Paul, MN: Red Leaf Press, 2000.

Palmer, J. A., ed. Fifty Modern Thinkers on Education. From Piaget to the Present. London; New York: Routledge, 2001.

Piaget, J. Genetic epistemology. Trans. by Eleanor Duckworth. New York: Columbia University Press, 1970.

Piaget, J. (1952). "Jean Piaget (Autobiography)". In A History of Psychology in Autobiography, Vol. 4 (pp. 237–256). Edit. by E.G. Boring. Englewood Cliffs, NJ: Prentice Hall; 1974.

Piaget, J., and Inhelder, B. The Psychology of the Child. New York: Basic Books, 1969. (Original work published 1966).

Singer, Dorothy G. and Tracey A. A Piaget Primer: How a Child Thinks. Revenson Madison, CT: International Universities Press, 1997.

Wood, D. How Children Think and Learn. Oxford: Blackwells, 1998.

PIAGET, JEAN

(b. Neuchâtel, Switzerland, 9 August 1896; d. Geneva, Switzerland, 16 September 1980),

psychology, epistemology, biology.

Piaget is best known for his studies on the development of human intelligence from infancy to adolescence. He contributed crucially to the shaping of twentieth-century child psychology, cognitive psychology, and educational theory and practice. Nevertheless, he always considered that his specific domain was that of “genetic” (in the sense of “developmental”) epistemology, and he saw psychology as an instrument for developing a theory of scientific knowledge, specifically for understanding the growth of knowledge and the emergence of the concepts and cognitive mechanisms that make science possible. The idea of “intelligence,” as he used it, encompassed the capacities (such as that for abstraction and logical thinking) and notions (such as time, space, and substance) that are constitutive of scientific thought. His oeuvre includes more than fifty books and hundreds of articles.

Piaget’s entire professional life took place in Switzerland. After a dissertation in the natural sciences (1918) at the University of Neuchâtel, and studies in psychology and philosophy in Zürich and Paris, Piaget joined the Jean-Jacques Rousseau Institute of Geneva in 1921. Founded by the Genevan psychologist Édouard Claparède as a center for research on child development and education, the institute evolved into the Department of Psychology and Education of the University of Geneva. In the course of his long academic career, Piaget taught experimental and developmental psychology, sociology, and history of scientific thought, mostly at the University of Geneva. From 1929 to 1967 he also directed the International Bureau of Education, originally established to coordinate educational information and research, and to promote peace and international understanding through education. In 1955, with support from the Rockefeller Foundation, he created the interdisciplinary International Center for Genetic Epistemology (which closed in 1984). Piaget received numerous honorary doctorates (the first one from Harvard University in 1936), as well as such prestigious international awards as the Erasmus (1971) and Balzan (1979) prizes.

Early Development Piaget was born in 1896 in the French-speaking Swiss city of Neuchâtel to Rebecca-Suzanne Jackson, a religious mother with socialist leanings, and Arthur Piaget, an agnostic medievalist who was professor at the University of Neuchâtel and director of the local State Archives. In his 1952 autobiography, Piaget described his early commitment to “serious work” as a way of escaping the difficult family situation created by his mother’s mental instability. From 1910 to 1915 Piaget was active in the Club des Amis de la Nature (Club of the friends of nature), an amateur naturalist society for high-school students, supported by parents and local naturalists and academics. Shortly after an early initiation to malaco-logical taxonomy with Paul Godet, director of the

Neuchâtel Museum of Natural History (Musée d’histoire naturelle), he immersed himself in mollusk classification; by the time he finished his doctoral thesis on the taxonomy of Alpine mollusks (1918), he had published numerous articles in specialized journals. He later traced his “biological” view of intelligence as an adaptive function to this early scientific activity, which (in his 1952 autobiography) he also thanked for having protected him against the “demon of philosophy.” Piaget’s turn from classificatory natural history to problems of adaptation and evolution, however, were largely due to his adolescent philosophical outlook.

Piaget became interested in the nature of life and evolution in 1912, after reading Creative Evolution (1907) by the French philosopher Henri Bergson. Inspired by this celebrated work, he rejected the Darwinian theory of natural selection (to which he would always prefer a form of Lamarckism), and he adopted the basic postulate of his later thought: the idea that the theory of knowledge and the theory of life are inseparable. He nevertheless stayed with classificatory natural history until his 1918 thesis; later, at a time when he was already involved in psychological research, he undertook a years-long “biometrical and genetic” study of the freshwater snail Limnaea stagnalis’s adaptation to natural lake environments. In 1929 he published a major monograph on the topic, thus giving closure to his empirical work in the natural sciences.

During his high school studies (1912–1915), Piaget began a lifelong friendship with his philosophy teacher and mentor Arnold Reymond. (After graduating in theology in 1900 with an essay on “subjectivism and the problem of religious knowledge,” Reymond served as a Protestant minister for three years before turning to philosophy and the history of science, specializing, at the time he was Piaget’s teacher, in the history of logic and mathematics in Greco-Roman antiquity.) During World War I, Piaget joined socialist and Christian youth groups, and he spent time at a sanatorium in Leysin, in the Swiss Alpine canton of Vaud, a place reminiscent (in some literature of the time) of Thomas Mann’s “magic mountain.”

In ways that are also reminiscent of Mann’s characters, the young Piaget went through deep crises in which issues of personal identity merged with religious and political questions, a revolt against bourgeois conservatism and the official churches, and the aspiration to work for the “new birth of Christianity.” Combining Bergson’s doctrine of the élan vital and the philosophy of religion “based on psychology and history” of the French theologian Auguste Sabatier, Piaget sketched a “Bergsonian Protestantism” in which the evolution of dogmas was a part of “creative evolution.” In March 1914 he published a comparison of Bergson and Sabatier, his first article outside the domain of natural history. Piaget obliterated these experiences and ideas from his later autobiographical writings, but left Abūndant traces of them in such youthful writings as the prose poem The Mission of the Idea (1915); a “prayer” titled “Les mystères de la douleur divine” (The Mysteries of Divine Suffering, 1916), in which a desperate man discovers God’s fraternity with humanity; and the 1918 article “Biology and War,” in which he asserts that to struggle against war is to follow the “logic of life.” He also described his youthful crises and their solution in Recherche (1918; Quest), an autobiographical Bildungsroman and philosophical essay that was severely criticized by Reymond. (Piaget, 1977c, includes a partial translation of Mission, a complete translation of “Biology and War,” and a chapter-by-chapter summary of Recherche. The full text of Recherche is available at the site of the Jean Piaget Foundation; see Bibliography below.)

In Recherche, Piaget elaborated a theory of organic, psychological, and social phenomena based on the idea of equilibrium between parts and wholes. While real-life dis-equilibria (between individual and collective interests, for example) tend toward equilibrium, disequilibria can lead to such events as war. Piaget’s ultimate goal was the new birth of Christianity and the reconstruction of postwar humanity. Much of his later thinking built directly on these youthful speculations and values, but its empirical impetus derived from a reaction against the metaphysical and mystical inclinations of his adolescence.

The Child’s “Mentality.” After spending the winter semester of 1918–1919 in Zürich, where he enrolled at the university but mainly attended lectures on psychoanalysis (a field he knew since 1916), Piaget left for Paris, where he went to classes and lectures in psychiatry, logic, and philosophy of science. In the fall of 1919, he gave a lecture on psychoanalysis and child psychology (a special Swiss interest), which was one of the first psychoanalytic presentations on French soil. In Zürich he tried out psychoanalysis, both as a practitioner and as a patient. Thanks to a recommendation from Pierre Bovet (a friend of Piaget’s family and director of the Rousseau Institute), Théodore Simon, who had collaborated with Alfred Binet in developing intelligence tests, asked Piaget to standardize Cyril Burt’s tests for Parisian children. Rather than adhere to the task, Piaget focused on how children proceeded and then justified their answers.

In the early 1920s Piaget combined the use of items from intelligence tests, new problem-solving situations, and open-ended conversations with school-age children into what he called the “clinical method.” His first five books (1923–1932) use this method to examine the development of the child’s language, reasoning, conceptions of the world, theories of causality, and moral judgment. Piaget found that children are at first “egocentric” (i.e., cannot take another person’s point of view) and attached to concrete appearances, but that they gradually move away from egocentrism and become capable of reciprocity and of thinking abstractly and logically. Earlier child study had focused on the contents of the children’s minds and inventoried age-related behaviors; Piaget concentrated on the main features of children’s “mentality.” In so doing, he drew inspiration from work by the French ethnologist Lucien Lévy-Bruhl, who described “primitive mentality” as prelogical and mystical. Piaget’s first books also bear the traces of his psychoanalytic interests, and they reveal various influences, especially that of Zürich psychiatrist Eugen Bleuler, who coined the term schizophrenia and described the “autistic thinking” to which Piaget compared egocentric thought; that of two of his Paris teachers, the psychiatrist Pierre Janet and the philosopher Léon Brunschvicg; and that of James Mark Baldwin, the American pioneer of “genetic” psychology and epistemology.

In his first books, Piaget sometimes presented the development of intelligence as a process of socialization of thought that is largely driven by social interactions; in The Moral Judgment of the Child, for example, he argued that children leave egocentrism behind as the result of the practice of cooperation among peers. In the 1920s Piaget

rapidly gained an international reputation, and within the progressive education movement his work seemed to provide scientific support for pedagogical methods based on children’s interests, activity, and “self-government.” He described development as moving from egocentrism (which manifested itself as children’s dependence on perceptual appearances and acceptance of external authority) toward logical thinking and moral autonomy. He also pursued research on mollusk adaptation, and he wrote about epistemological, sociological, and religious topics.

The totality of Piaget’s writings at the time shows that, for him, development in ontogeny went in the same direction as historical progress: from the child and the primitive to the adult and the modern, from heteronomy to autonomy in the cognitive and moral domains, from authoritarian regimes to parliamentary democracy, and from dogmatic religions to liberal Protestantism. The Moral Judgment of the Child, a book of great personal significance that is connected to Piaget’s political ideals and to his defense of “immanence” in religion, closes the first phase of his work.

Infancy, Logic, and Stages Starting in the mid-1920s, with the help of his wife (and former student) Valentine Châtenay, Piaget studied his three children, born in 1925, 1927, and 1931, and recorded his observations in three major classics. The Origins of Intelligence and The Construction of Reality (1936–1937) describe how basic forms

of intentionality and of the categories of object, space, causality, and time evolve between the newborn’s reflex activities and the emergence of language at about eighteenth months. Play, Dreams, and Imitation, originally titled La formation du symbole chez l’enfant. Imitation, jeu et rêve, image et représentation, appeared in 1945, but was largely composed earlier; it deals with the development of mental representation up to the age of six. Piaget was criticized for drawing general conclusions from the observation of a very small number of subjects, who were in addition his own children. At the time, however, studying few subjects—and one’s children—was current and legitimate within psychology.

In The Origins of Intelligence, Piaget linked biological, epistemological, and psychological theories. He characterized human intelligence as a form of adaptation that prolongs organic adaptation and employs the same mechanisms of “assimilation” and “accommodation” (which he also termed the “functional invariants” of development). He asserted the primary role of activity, and he criticized both nativism and empiricism. He later called his approach constructivist, meaning by this term that the concepts and structures of intelligence are constructed and reconstructed by means of the physical and mental activities whereby the organism adapts to the external world. The books Piaget derived from observing his children constitute a second group of works, after which Piaget turned to the study of logical thinking, adopting formal logical and mathematical models to characterize mental “structures” and “operations.”

In the 1930s Piaget and his former student Bärbel Inhelder began a remarkable instance of scientific collaboration that lasted until Piaget’s death. By the 1940s, Inhelder recalled in her autobiography, Piaget said he needed her “to counter his tendency toward becoming a totally abstract thinker.” In 1948 Inhelder became professor at the University of Geneva. While Piaget never lost sight of his epistemological goals, Inhelder was more of a psychologist, devising many of the problem-solving situations that have become the distinguishing feature of Piagetian research. Their first collaborative work, on the child’s understanding of quantity conservation, appeared in 1941; in her dissertation, published in 1943, Inhelder made pioneering use of conservation tests as diagnostic tools. Together, they wrote books on the development of logic and the conceptions of movement, speed, time, space, geometry, chance, and probability.

Together with The Origins of Intelligence and The Construction of Reality, these books describe a sequence of four developmental stages from birth through adolescence. Piaget, who has often been reduced to a “stage theorist,” maintained that the stages appear in an invariable order, but recognized that they do so at somewhat different ages

in different individuals, cultures, and settings. The stages are named sensorimotor (from birth to about two years), preoperational (until about age seven, sometimes defined as an initial substage of the following one), concrete operational (until about age eleven), and formal operational. This sequence highlights “operational” thought as the point toward which development tends. For Piaget, “operations” are interiorized actions that have become reversible and coordinated with other interiorized actions into a totality; cognitive development therefore consists of the emergence of such operations. It begins with the transformation of innate reflexes into action “schemes,” whereby the subject initially assimilates the world and accommodates to it, through the child’s “operational” activities (e.g., classification and seriation of concrete objects), to the adolescent’s capacity for hypothetico-deductive thinking.

The Growth of Logical Thinking from Childhood to Adolescence: An Essay on the Construction of Formal Operational Structures (1953) and The Early Growth of Logic in the Child (1959), which are among the most influential works coauthored by Piaget and Inhelder, define the stage of “formal operations.” Piaget argued that adolescents actually (though intuitively) employ the operations of propositional logic. In his view, because logic represents the axiomatization of the internal structures of thought, and because thought derives from biological mechanisms and is an adaptive function, logico-mathematical structures are “biological” and developmentally “constructed.” This would explain their power to describe reality. Parallel to empirical investigations, Piaget published (in 1942, 1949, and 1952) elaborate studies in “logistic” (a term to be understood as the elaboration of abstract models for describing the logico-mathematical operations that manifest themselves behaviorally or psychologically). These untranslated books have been variously criticized by philosophers, logicians, and psychologists as psychologistic, logicistic, or conceptually and formally flawed.

Biology, History of Science, and Piagetian Tasks In addition to the topics already mentioned, Piaget, Inhelder, and their numerous collaborators investigated the mechanisms of perception, the relations between memory and intelligence, mental image, causal and physical explanations, number, the grasp of consciousness, contradiction, generalization, possibility, and necessity. Thirty-seven volumes of the collaborative Études d’épistémologie génétique (Studies of genetic epistemology) were published between 1957 and 1980. Starting in the 1960s, Piaget also published several theoretical books, including: Insights and Illusions of Philosophy (1965, with an autobiographical first chapter); Biology and Knowledge: An Essay on the Relations between Organic Regulations and Cognitive Processes (1967); Structuralism (1968); Genetic Epistemology (1970); Adaptation and Intelligence (1974, originally titled Adaptation vitale et psychologie de l’intelligence: Sélection organique et phénocopie); The Equilibration of Cognitive Structures (1975); and Behavior and Evolution (1976, originally titled Le comportement, moteur de l’évolution). Piaget’s three-volume Introduction à l’épistémologie génétique (1950; Introduction to genetic epistemology, 1: mathematical thought, 2: physical thought, 3: biological, psychological and sociological thoughts) remains untranslated.

Piaget was driven by the goal of elaborating a theory of knowledge that would demonstrate empirically, rather than philosophically, the conditions of possibility of scientific thought. Psychologizing the Kantian categories, he chose to ask how they develop. As illustrated by his objects of research and by the tasks he used to pursue them (see below), he identified “science” mainly with the physico-mathematical disciplines—hence, too, his steady interest in the history of science. In the general terms he used later in life, Piaget saw mental development and the history of science as a process of “equilibration” toward an ever-increasing capacity to assimilate the world. In the posthumous book Psychogenesis and the History of Science (1983, with Rolando García), Piaget established parallelisms between the two processes, thus elaborating on a postulate of his entire intellectual enterprise. He nevertheless focused on knowledge mechanisms rather than contents, thus distancing himself, in his own view, from the classical formulation of the biogenetic law “ontogeny recapitulates phylogeny.”

Piaget’s work prior to the infancy books was rapidly translated. A hiatus followed until the 1950s, when the critique of behaviorism stimulated a renewed interest and turned Piaget into a major inspiration for the “cognitive revolution.” His rediscovery in the 1960s began in the Americas, and was promoted by such presentations as John Flavell’s The Developmental Psychology of Jean Piaget(1963) in the United States and Antonio Battro’s Diccionario de epistemología genética (1966) and El pensamiento de Jean Piaget (1969) in Argentina. His work launched empirical investigations throughout the world. Although these investigations prolonged mainly the infancy books and especially the later studies, Piaget’s early work, The Moral Judgment of the Child (1932), in which he confronted children with moral dilemmas and observed them play games, was a major source of inspiration for the American student of moral development Lawrence Kohlberg, whose work has been immensely influential in the field.

The technically accessible nature of Piagetian tasks facilitated their adoption as research paradigms. In one famous instance, children are shown a scale model of three mountains and are asked to choose from a series of pictures the one that represents the mountains as seen by a

doll at other positions. “Egocentric” younger subjects identify the doll’s viewpoint with their own. In research on the conservation of substance, the child faces two identical balls of clay; the shape of one is modified, and the experimenter investigates whether and why the child believes the amount, weight, or volume of clay has changed. Other situations involve manipulating blocks or pouring identical quantities of liquid in differently shaped containers (children begin by saying there is more or less depending on whether they pay attention to height or width, and only later attain “reversibility”).

What Piaget described as the “triumph” of operation over perceptual intuition is further illustrated in a task from The Child’s Conception of Number (1941), coauthored with Alina Szeminska: two lines of beads, including the same number of items, are placed parallel to each other; the beads on one row are then set further apart or brought closer together, and children are asked about the transformation. The younger children believe that quantity has changed; the older ones, in contrast, use one-toone correspondence (which conflicts with perception) to conclude it has been conserved. In one study of inductive reasoning, subjects were asked to discover the factors (such as length or thickness) that make metal rods more or less flexible. First discussed in The Origins of Intelligence, the study of the “object concept” or “permanent object” by observing infants’ reactions after an object disappears from their view has, like many other Piagetian tasks, given rise to numerous variations, validation research (including intercultural studies), and theoretical discussions.

Critique and Assessment Much work of Piagetian inspiration has questioned Piaget’s conclusions, suggesting that children’s competencies appear earlier than he believed, that subjects “fail” the tests because they cannot make sense of them, that both the tasks and the results should be understood in a framework that includes not only cognitive, but also social, cultural, and affective factors, or that the structure of intelligence is domain-specific rather than homogeneous. Piaget devoted his 1953–1954 Sorbonne lectures to Intelligence and Affectivity: Their Relationship during Child Development (published in English in 1981). Nevertheless, his view that affect has a motivational and regulatory function (and may thus accelerate or delay development), while cognition provides the structures of thought, has not satisfied his critics. In the 1980s and 1990s, it became fashionable to contrast his viewpoint to the cultural-historical approach of the Soviet psychologist Lev Vygotsky.

Most “Piagetian” research is actually disconnected from the theoretical goals of genetic epistemology. Piaget’s overall views and goals, as well as his descriptions of the stages, mechanisms, and structures involved in the development of intelligence, have inspired research programs in various fields outside psychology, including the history of art, religion, and science. More than anything, however, it is Piaget’s investigative approach and empirical findings, his formulation of new problems, and his emphasis on cognitive development that contributed to shape child and cognitive psychology in the second half of the twentieth century. His work also had a significant impact on pedagogy, giving new impetus to the belief that instruction must adapt to children’s developmental levels and must involve their interests and activity. Its effect on teaching methods (especially in mathematics) was much more concrete and successful during the postwar period than in the interwar years. Nevertheless, even in the second half of the 1930s, when he published most of his reflections about education, Piaget distanced himself from professional pedagogues.

Similarly, Piaget gave psychology a preeminent place among the sciences, because, in his view, only psychology studies the development of the logico-mathematical operations that make science possible. But he insisted that he was not a psychologist, and explained that he studied the “epistemic” rather than the “psychological” subject. This claim provides the clue to a historical examination and assessment of Piaget’s contribution. Equally important for this purpose are the diversity and temporal dimension of his oeuvre, which evolved over more than six decades and includes not only psychology, but also sociology, philosophy of science and religion, theory of knowledge, education, and biology.

BIBLIOGRAPHY

WORKS BY PIAGET

“Bergson et Sabatier.” Revue chrétienne 61 (1914): 192–200. Piaget’s first article outside natural history.

“Les mystères de la douleur divine (1916).” In Fernando Vidal, “‘Les mystères de la douleur divine.’ Une ‘prière’ du jeune Jean Piaget pour l’année 1916” [“The mysteries of divine suffering”: A “prayer” for the year 1916 by the young Jean Piaget]. Revue de théologie et de philosophie 126 (1994): 97–118.

“L’adaptation de la Limnaea stagnalis aux milieux lacustres de la Suisse romande. Étude biométrique et génétique” [The adaptation of the Limnaea stagnalis to the lake environments of French-speaking Switzerland. A biometric and genetic study]. Revue suisse de zoologie 36 (1929): 263–531.

Immanentisme et foi religieuse [Immanentism and religious faith]. Geneva: Groupe romand des anciens membres de l’Association chrétienne d’étudiants, 1930. Piaget’s final statement on religion.

The Psychology of Intelligence (1947). Translated by Malcolm Piercy and D. E. Berlyne. Totowa, NJ: Littlefield, Adams, 1972. Together with Piaget and Inhelder (1966) and Piaget (1970a), one of Piaget’s somewhat difficult presentations of his thinking.

“Autobiography.” In A History of Psychology in Autobiography. Vol. 4, edited by Edwin G. Boring, et al. Worcester, MA: Clark University Press, 1952. Widely used, but biased and incomplete in its narrative of Piaget’s youth.

Logic and Psychology. Translated by Wolfe Mays. Manchester, U.K.: Manchester University Press, 1953.

Six Psychological Studies(1964). Translated by Anita Tenzer. New York: Vintage, 1968. Together with 1969, 1970b, 1972a, 1972b, and 1977a, one of Piaget’s several useful collection of articles from the 1940s through the 1960s.

With Bärbel Inhelder. The Psychology of the Child (1966). Translated by H. Weaver. New York: Basic Books, 1969.

Science of Education and the Psychology of the Child (1969). Translated by Derek Coltman. New York: Viking Press, 1971.

Psychology and Epistemology: Towards a Theory of Knowledge (1970b). Translated by P. A. Wells. Harmondsworth, U.K.: Penguin, 1972.

The Child and Reality: Problems of Genetic Psychology (1972a). Translated by Arnold Rosin. New York: Grossman, 1973.

To Understand Is to Invent: The Future of Education (1972b). Translated by George-Anne Roberts. New York: Grossman, 1973.

With Richard I. Evans. Jean Piaget: The Man and His Ideas. New York: Dutton, 1973. Together with 1977b, useful informal introduction to Piaget.

“Autobiographie” [Autobiography]. Revue européenne des sciences sociales (Cahiers Vilfredo Pareto) 14 (1976): 1–43.

Sociological Studies(1977a). Translated by Terry Brown, et al. Introduction by L. Smith. London and New York: Blackwell, 1995. Translates the second, expanded edition of Études sociologiques (first ed., 1965).

With Jean-Claude Bringuier. Conversations with Jean Piaget (1977b). Translated by Basia Miller-Gulati. Chicago: University of Chicago Press, 1989.

The Essential Piaget: An Interpretive Reference and Guide (1977c). Edited by Howard E. Gruber and Jacques Vonèche. New York: Basic Books, 1996. A valuable anthology with comments and introductions.

Studies in Reflecting Abstraction (1977d). Edited and translated by Robert L. Campbell. Hove, U.K.: Psychology Press, 2000. Empirical and theoretical studies on a process (abstraction refléchissante, also rendered as “reflective abstraction”) to which Piaget attributed a central role in the growth of knowledge.

Genetic Epistemology. Translated by Eleanor Duckworth. New York: Norton, 1979.

L’éducation morale à l’école: De l’éducation du citoyen à l’éducation internationale [Moral education in the school: From the education of the citizen to international education]. Edited by Constantin Xypas. Paris: Anthropos, 1997a. Selection of texts, 1928–1944. Overlaps with 1997b and 1998.

Piaget et l’éducation [Piaget and education]. Edited by Constantin Xypas. Paris: Presses universitaires de France, 1997b. Selection of texts, 1930–1966. Overlaps with 1997a and 1998.

De la pédagogie [On pedagogy]. Edited by Silvia Parrat-Dayan and Anastasia Tryphon. Paris: Odile Jacob, 1998. Selection of texts, 1930–1976. Overlaps with 1997a and 1997b.

“La vanité de la nomenclature” et autres écrits de jeunesse de Jean Piaget [“The vanity of nomenclature” and other early writings by Jean Piaget], edited by Fernando Vidal, 1999. Available from http://www.piaget.org/piaget/. Manuscripts and other materials from the Club des Amis de la Nature, 1910–1915.

OTHER SOURCES

Barrelet, Jean-Marc, and Anne-Nelly Perret-Clermont, eds. Jean Piaget et Neuchâte: L’apprenti et le savant [Piaget and Neuchâtel: The apprentice and the scholar]. Lausanne, Switzerland: Payot, 1996.

Battro, Antonio. Piaget: Dictionary of Terms (1966). Translated by Elizabeth Rütschi-Hermann and Sarah F. Campbell. New York: Pergamon, 1973.

Boden, Margaret. Jean Piaget. Harmondsworth, U.K.: Penguin, 1979. Excellent short introduction.

Catalogue annuel des Archives Jean Piaget (previously Catalogue des Archives Jean Piaget). Geneva: Fondation Archives Jean Piaget. Annual bibliographies of Piaget-related publications.

Chapman, Michael. Constructive Evolution: Origins and Development of Piaget’s Thought. New York: Cambridge University Press, 1988. Like Kitchener, but more comprehensive and biographical, a complex analysis of Piaget’s work.

Ducret, Jean-Jacques. Jean Piaget: Biographie et parcours intellectuel [Jean Piaget: Biography and intellectual itinerary]. Neuchâtel, Switzerland: Delachaux et Niestlé, 1990. Illustrated.

Inhelder, Bärbel. “Autobiography.” In A History of Psychology in Autobiography, vol. 8, edited by Gardner Lindzey. Stanford, CA: Stanford University Press, 1989.

Kitchener, Richard F. Piaget’s Theory of Knowledge: Genetic Epistemology and Scientific Reason. New Haven, CT: Yale University Press, 1986.

Montangero, Jacques, and Danielle Maurice-Naville. Piaget, or, The Advance of Knowledge. Translated by Angela Cornu-Wells. Mahwah, NJ: Erlbaum, 1977. Like Battro, a glossary (this one limited to Piaget’s psychological work).

Smith, Leslie, ed. Jean Piaget. Critical Assessments. 4 vols. London and New York: Routledge, 1992.

Vidal, Fernando. Piaget before Piaget. Cambridge, MA: Harvard University Press, 1994. A historical and contextual biography focused on Piaget’s youth.

———. Piaget neuchâtelois. Neuchâtel, Switzerland: Bibliothèque publique et universitaire, 1996. An illustrated exhibition catalog.

———. “Immanence, affectivité et démocracie dans Le jugement moral chez l’enfant” [Immanece, affectivity and democracy in The Moral Judgment of the Child]. Bulletin de psychologie 51, no. 437 (1998): 585–597. Discusses the origins and significance of The Moral Judgment, as well as Piaget’s religious writings of the 1920s.

Fernando Vidal

Piaget, Jean 1896-1980

BASIC CONCEPTS: DEVELOPMENTAL STAGES

BASIC CONCEPTS: THE PROCESS OF DEVELOPMENT

CRITICISM OF THE THEORY

BIBLIOGRAPHY

Considered by many to be the founder of modern developmental psychology, the Swiss psychologist Jean Piaget devoted his researches to children’s distinctive ways of knowing and to the process of developmental change leading toward adult thought. He charted a sequence of stages in children’s intellectual development whose manifestations encompass domains ranging from logical reasoning to emotional development. Trained in biology and philosophy, Piaget extrapolated from his studies of mollusks in their natural habitat to a conception of the development of intelligence in children as a progressive adaptation, tending toward ever greater equilibrium, with its reciprocal aspects of the “assimilation” of new information to existing concepts and the “accommodation” (i.e., modification) of the concepts to the new information. He viewed the development of intelligence, in turn, as the foundation of a “genetic epistemology,” a theory of knowledge that conceived the development of ideas as part of their essence. On the basis of his observations of children’s cognitive development and his claim that children’s own action catalyzes that development, Piaget altered the face of psychology and education.

BASIC CONCEPTS: DEVELOPMENTAL STAGES

Piaget became convinced that children exhibit a distinctive type of thinking, as opposed to simply flawed adult thought, when, as a young associate working on intelligence testing in the laboratory of Alfred Binet (1857–1911), he noticed that when children answered items incorrectly, they tended to give the same wrong answer. He inferred that the children must have approached the problems methodically, only the method differed from that of adults. After altering the testing methods to include the exploration of children’s answers and devising many probes of his own, he set about determining the intellectual organization of what he eventually conceived as four broad stages of development, each embodying a progression toward increasingly flexible, systematic, and complex thought: sensorimotor, preoperational, concrete-operational, and formal operational.

During the sensorimotor period, extending from birth to approximately eighteen months, intelligence manifests in action. Action develops within the period from reflexive movement to means-ends behavior that comes, by the last of six substages, to incorporate tool use, foresight, and detours ([1936] 1952). The advent of representational intelligence in the sixth substage manifests in additional ways, including deduction based upon remembered events, the imitation of events witnessed previously, symbolic play, and language. Thought now progresses to some degree independently of what is seen or otherwise directly experienced. For example, an eighteen-month-old child who sees a toy hidden in a box, then sees the box moved under a cloth, and then finds the box empty, will spontaneously search under the cloth for the missing toy, evidently having inferred that the toy left the box when the box was under the cloth (an instance of deduction). Children at this age might also imitate a funny face someone made the day before (an instance of deferred imitation) or slide a leaf along the countertop as though the leaf were a car (an instance of symbolic play). Although any of these representational activities might occur in the absence of language, language, which also depends upon conceptual connections, normally begins at around the same time.

These symptoms of nascent representational thought mark the beginning of Piaget’s second broad stage, of preoperational or intuitive intelligence, which extends roughly from two to seven years of age. Piaget found that, despite the advances it embodied, thought during this interval exhibited limitations, in particular with respect to the property of what he termed reversibility. The limitation is apparent in Piaget’s best-known experiment with school-age children, his probe of what he called the “conservation” of quantity. When water, for example, is poured from a wide flask into a thin one, although adults or older children know the water level must rise, children under the age of (approximately) seven years sometimes anticipate that the water level will remain the same. Alternatively, when confronted with the raised water level after the water is poured, they may assert that the new (thin) flask contains more water than did the original (wide) flask ([1941] 1965).

By comparison, when presented with the same problem, children between seven and twelve years, normally the stage of concrete-operational thought, say the amount of liquid must remain the same because, for example, if one returned the water to the original flask, the water would rise to the level it reached initially. Or, they might say that although the level is higher in the second flask than it was in the first, the second flask is also narrower, or that nothing was added or taken away. Piaget perceived in these arguments the imagined reversal of an observed state of affairs and the construction of compensations between different variables of the problem.

The state of affairs had to be concrete and observable, however, whereas from roughly twelve years onward, during the formal operational stage, individuals can reason about hypothetical states and solve both abstract and concrete problems systematically, by taking account of, and if necessary manipulating, all variables pertinent to a problem. Thus, as a scientist would do, a child at this stage confronted with the problem of determining which of a series of chemicals was responsible for altering the color of a solution, for instance, would systematically vary each possible combination of liquids to isolate the necessary reaction (Inhelder and Piaget [1955] 1958).

Development through the stage of concrete operations is believed to be universal, whereas only a fraction of even well-educated teenagers from the United States exhibit formal operational reasoning when they are given the problems originally employed by Piaget. As suggested by Jean Retschitzki (1989) in a study of expert players of a popular game in the Ivory Coast, however, evidence exists that formal-operational reasoning may be employed even by members of undeveloped countries with low literacy when people participate in culturally indigenous activities in which they are expert.

Piaget characterized these tiers of development in a second way, as embodying three “Copernican revolutions” ([1964] 1968), in which children, initially “egocentric” at the level in question, gradually progressed toward the ability to take alternative perspectives into account. Although Piaget eventually retracted the term egocentric in response to its apparent misconstrual by other psychologists, he retained the substantive theses underlying it.

During the sensorimotor period of infancy, as conceived within this second scheme, children come gradually to acknowledge a self, a world, and their separation. They come to recognize, for example, that their caregivers come and go on their own and that the external world generally operates independently of them ([1937] 1954).

During the preoperational period of early childhood, children progress from an obliviousness to the perspective of others to the awareness that others may perceive things differently from what they perceive, and they anticipate the alternative perspective. Thus, for instance, whereas when an interlocutor’s back is turned, a four-year-old might point to the location of an object for which the interlocutor is searching, an older child would describe the location ([1923] 1955).

Corresponding to the advent of the capacity for formal operations is an interest in abstract ideals and, according to Piaget, a progression during adolescence from the view that the world should submit to one’s schemes to the understanding that one does not know everything ([1964] 1968).

Piaget believed his stage sequences extended to many areas of cognition, including logical thought and children’s conceptions of objects, space, time, causality, number, chance, and probability, as well as aspects of perception and memory. He perceived their manifestations also in areas of social life, especially morality. Corresponding to the progression he observed toward concrete operations, for example, he documented the emergence of an understanding of and interest in social rules and an appreciation of their purpose in regulating people’s relations and protecting their welfare. He also documented a trend from the negative moral valuation of people whose actions produce bad outcomes to the negative valuation of those whose intentions are bad ([1932] 1965).

In delineating the myriad developments he did, Piaget ascribed greater importance to the sequence of developments he described than to the uniformity of development across areas of activity. He believed, however, that the capacity for more primitive types of reasoning remained in all areas throughout life and, especially in the case of morality, were more evident in some individuals and groups than in others.

BASIC CONCEPTS: THE PROCESS OF DEVELOPMENT

All of the developments Piaget described resulted, he believed, from natural, spontaneous development. With the possible exception of moral judgment, whose early stages he suggested reflected the influence of adult disciplinary tactics, the developments were not taught or otherwise prompted by the environment, which at most afforded (or limited) opportunities for growth. He contended, moreover, that the advances he charted arose through feedback from children’s own action, as opposed to from the maturation of innately given abilities.

Piaget was sufficiently convinced of the potential of the mind to construct itself that he believed the entire series of developments he described evolved from a starting point of only reflexive action and the “invariant functions” of assimilation, accommodation, and the progressive storage of their results, which Piaget called organization. Merely by sucking, grasping, listening, and looking—initially reflexively—and repeating these behaviors, as followed from the inborn tendency to repeat experiences (the most primitive manifestation of assimilation), the resulting chance effects would eventually bring about change in the actions. Further changes would follow from there, until individuals reached the final equilibrium of adult forms of thought ([1936] 1952).

CRITICISM OF THE THEORY

Piaget’s studies of children have been replicated worldwide, in both developed and undeveloped countries. Many have also extended his sequences to domains he did not investigate, such as attachment relations in infancy and friendships during childhood.

The theory has also been challenged by researchers who, after modifying the measures Piaget used to assess the abilities he investigated, have produced results the researchers believe attest to children’s grasp of mature concepts at an earlier stage than Piaget specified. Some of this work appears in reviews by Paul Harris (1989) and John Flavell and colleagues (2002). The researchers assert that the results warrant a different model of development in which, rather than gradually developing the concepts in question, as Piaget described, children begin development in possession of the concepts’ essentials and progressively “access” the essentials in increasingly reflective thought and over ever broader areas of application; Paul Rozin lays out a version of the model in “The Evolution of Intelligence and Access to the Cognitive Unconscious” (1976). According to the general view, younger children falter on Piaget’s tasks not because they lack the concepts under examination, but because they become confused by nonessential features of Piaget’s experiments. With age, the view says, as children’s working memory and attentional capabilities increase, children became better able to negotiate Piaget’s tasks.

Some researchers in the foregoing line have challenged Piaget’s theory based not upon new experimental procedures, which most of the aforementioned studies employ, but upon naturalistically occurring behavior, a focus more in keeping with Piaget’s original observations. For example, in 1973 Marilyn Shatz and Rochel Gelman reported that, contrary to the idea that preschoolers fail to take in others’ perspectives when addressing them, four-year-olds simplify their speech when they talk to two-year-olds. More recently, Debra van Ausdale and Joseph Feagin (2001) found evidence in preschoolers’ social interactions of racist ideas and practices that the authors believe possible only with the “operational” thought Piaget ascribed to middle childhood.

Another line of criticism questions the cogency of Piaget’s theoretical constructs independently of the data, as exemplified by works by Sophie Haroutunian (1983) and Susan Sugarman (1987a), or the formalisms he used to represent the constructs, as argued by Daniel Osherson (1974).

Few dispute Piaget’s sequences as measured by his own tests. Controversy continues about the equivalence of the concepts measured by newer tests to the concepts assessed by Piaget’s procedures. The two bodies of work differ fundamentally in method. Whereas the work that challenges Piaget’s norms replaces his tests at younger ages, Piaget extrapolated to his sequences from developmental changes in children’s behavior on the same measure at all ages he tested; the strategy dates to Piaget’s days as a researcher in intelligence testing. The difference makes it difficult to render any final conclusion about the import of the apparently conflicting results (see Sugarman 1987b for discussion of this).

With respect specifically to the challenges brought by fresh observations of naturally occurring behavior, evidence can be found within Piaget’s own observations of allegedly “preoperational” thought more complex than that ascribed by his account of preoperational thinking (Sugarman 1987a). Nonetheless, the particular complexities Piaget associated with “operational” thinking, in the abstract reflective thought in which he sought them, do not appear in either Piaget’s or newer data. The claim that the racist ideas and practices of some preschoolers require operational thought presents the additional problem that racism bears precisely the hallmarks of preoperational mentality as Piaget originally defined it. These properties include a one-sided point of view, often based upon appearances, that does not take account of alternative vantage points, is impervious to contradiction, and consequently remains unaware of itself as a point of view. Especially in the moral domain, which, as Piaget discusses in The Moral Judgment of the Child ([1932] 1965), draws upon incompletely comprehended adult influences, thought can become rigid and nearly mystical as a result of these tendencies. Given the persistence of these characteristics into adult morality, the telling question raised by the observation of racism in preschoolers might be not how preschoolers manage to exhibit racism, but why adults remain susceptible to it, given their apparent possession of more sophisticated forms of thought.

Despite the empirical challenges to his theory, Piaget’s developmental milestones in children’s thought dominate research in developmental psychology and retain a strong influence in education. Although conceptual critiques of the theory suggest the presence of gaps in the edifice, Piaget’s general philosophy of how development occurs, namely through the exertions of a knowing subject, remains widely embraced.

SEE ALSO Cognitive Dissonance; Intelligence

BIBLIOGRAPHY

PRIMARY WORKS

Inhelder, Bärbel, and Jean Piaget. [1955] 1958. The Growth of Logical Thinking from Childhood to Adolescence: An Essay on the Construction of Formal Operational Structures. New York: Basic Books.

Piaget, Jean. [1923] 1955. The Language and Thought of the Child. Trans. Marjorie and Ruth Gabain. New York: Meridian.

Piaget, Jean. [1932] 1965. The Moral Judgment of the Child. Trans. Marjorie Gabain. New York: Free Press.

Piaget, Jean. [1936] 1952. The Origins of Intelligence in Children. Trans. Margaret Cook. New York: International Universities Press.

Piaget, Jean. [1937] 1954. The Construction of Reality in the Child. Trans. Margaret Cook. New York: Basic Books.

Piaget, Jean. [1941] 1965. The Child’s Conception of Number. Trans. Caleb Gattegno and F. M. Hodgson. New York: Norton.

Piaget, Jean. [1964] 1968. Six Psychological Studies. Trans. Anita Tenzer. New York: Vintage Books.

SECONDARY WORKS

Cole, Michael. 1996. Cultural Psychology: A Once and Future Discipline. Cambridge, MA: Harvard University Press.

Flavell, John H., Patricia H. Miller, and Scott A. Miller. 2002. Cognitive Development. Englewood Cliffs, NJ: Prentice-Hall.

Haroutunian, Sophie. 1983. Equilibrium in the Balance: A Study of Psychological Explanation. New York: Springer-Verlag.

Harris, Paul L. 1989. Object Permanence in Infancy. In Infant Development, eds. Alan Slater and Gavin Bremner, 103–121. Hillsdale, NJ: Lawrence Erlbaum.

Osherson, Daniel N. 1974. Organization of Length and Class Concepts: Empirical Consequences of a Piagetian Formalism. Vol. 1 of Logical Abilities in Children. Hillsdale, NJ: Lawrence Erlbaum.

Retschitzki, Jean. 1989. Evidence of Formal Thinking in Baoule Awele Players. In Heterogeneity in Cross-Cultural Psychology: Selected Papers from the Ninth International Conference of the International Association for Cross-Cultural Psychology, eds. Daphne M. Keats, Donald Munro, and Leon Mann, 234–243. Amsterdam and Rockland, MA: Swets and Zeitlinger.

Rozin, Paul. 1976. The Evolution of Intelligence and Access to the Cognitive Unconscious. In Progress in Psychobiology and Physiological Psychology, vol. 6, eds. James M. Sprague and Alan D. Epstein, 245–280. New York: Academic Press.

Shatz, Marilyn, and Rochel Gelman. 1973. The Development of Communication Skills: Modifications in the Speech of Young Children as a Function of Listener. Monographs of the Society for Research in Child Development 38 (5): 1–38.

Sugarman, Susan. 1987a. Piaget’s Construction of the Child’s Reality. New York: Cambridge University Press.

Sugarman, Susan. 1987b. The Priority of Description in Developmental Psychology. International Journal of Behavioral Development 10: 391–414.

Van Ausdale, Debra, and Joe R. Feagin. 2001 The First R: How Children Learn Race and Racism. Lanham, MD: Rowman and Littlefield.

Susan Sugarman

PIAGET, JEAN (1896–1980)

Director of the Institute of Educational Science in Geneva and professor of experimental psychology at the University of Geneva, Jean Piaget was the most influential developmental psychologist of the twentieth century. Many of Piaget's concepts and research methods have become so much a part of the conventional wisdom and practice that psychologists are often unaware of their origin. The stages of development that Piaget observed and conceptualized are given extended treatment in every introductory psychology and developmental psychology textbook. In addition, much of contemporary research on infancy grows directly out of Piaget's innovative studies of his own three infants. Moreover, a great deal of present day research and theory regarding adolescence starts from Piaget's demonstration of the appearance of new, higher level, mental abilities during this age period. In these and in many other ways, Piaget's research and theory continue to be a powerful stimulus in many different fields and areas of investigation.

Piaget's work, however, has had an impact on other disciplines as well. The contemporary emphasis upon constructivism in education, for example, stems directly from Piaget's theory of intellectual development. According to Piaget the child does not copy reality, but rather constructs it. Reality is developmentally relative; it is always a joint product of the child's developing mental abilities and his or her experiences with the world. Piaget's research and theory has also had considerable impact upon psychiatry. His description of the intellectual stages of development has provided a very important complement to the psychosexual stages of development outlined by the Austrian psychologist Sigmund Freud. In these, and in many other ways, the power of Piaget's work continues to be felt in many diverse fields.

Jean Piaget was born in Neuchâtel, Switzerland. His father was a classics professor at the University of Neuchâtel while his mother was a deeply devout Christian. In his autobiography, Piaget suggests that the ongoing conflict between his father's scientific beliefs and his mother's spiritual convictions contributed to his theory of mental development. He came to regard the development of intelligence as motivated by the progressive resolution of conflicting ideas. Be that as it may, Piaget showed his genius early. At the age of fourteen he published his first scientific paper, his observations of an albino sparrow. He also became, thanks to the mentorship of the curator of the Neuchâtel natural history museum, a student of mollusks. He began experimenting with crustaceans and publishing his findings in the biological journals. These articles were so well received that he was offered the curatorship of a natural history museum in another Swiss canton. Piaget, however, had to refuse because he had not yet graduated from high school.

Once at the university, Piaget took courses in both philosophy and biology and struggled to find some way to reconcile his philosophical interests with his commitment to science. He hit upon a unique solution in an unexpected place. After receiving his doctorate, Piaget explored a number of different professions including psychiatry. He eventually took a position in Paris, translating some of the intelligence tests created by the English psychologist, Sir Cyril Burt, into French. As part of this endeavor, it was necessary for Piaget to test a number of children in order to ensure that his translations had not made the items easier or more difficult than they were for English children of comparable age. While administering these tests, Piaget became fascinated with the children's wrong answers. To Piaget, these wrong answers did not seem random. Rather they appeared to be generated by a systematic way of seeing things that was not wrong, but simply reflected a different world view than that held by adults.

Piaget was fascinated by his unexpected discovery that children's perception of reality was not learned from adults, as had heretofore been assumed, but was constructed. Children's conception of the world, Piaget reasoned, was different than that of adults because their thought processes were different. Piaget assumed that he would pursue this problem, the development of children's thinking, for a few years and then move on to other things. Instead, this pursuit of the ways in which children construct reality, became the foundation of a lifelong professional career. Piaget came to realize that the study of the development of children's adaptive thought and action, of their intelligence, was a way of pursuing both his philosophical and his scientific interests.

One field of philosophy is epistemology, the study of how people come to know the world. Most philosophers approach this topic by means of introspection and logical analysis. Piaget, however, believed that he could put epistemological questions to the test by studying the development of thought and action in children. Accordingly Piaget created his own new discipline with its own methods and problems. The field was genetic epistemology, the study of child development as a means of answering epistemological questions. Piaget's career exploration of genetic epistemology can be roughly divided into four different stages.

Stage 1: The Sociological Model of Development

During this first stage, roughly corresponding to the 1920s, Piaget investigated children's heretofore unexplored conceptions of the world, the hidden side of children's minds. To further this exploration Piaget made use of a combination of psychological and clinical methods that he described as the semiclinical interview. He began with a standardized question, but followed up with nonstandard questions that were prompted by the child's answer. In order to get what Piaget called children's "spontaneous convictions" he often asked questions that the children neither expected nor anticipated. In his study of children's conception of the world, for example, he asked children whether a stone was alive and where dreams came from. He made a comparative study of children's answers and found that for these and for similar questions there was a gradual progression from intuitive to scientific and socially acceptable responses.

During this early period, Piaget published The Language and Thought of the Child, The Child's Conception of the World, The Child's Conception of Physical Causality, and The Moral Judgment of the Child. Each of these books was highly original and they made Piaget world famous before he was thirty. In these books he elaborated his first theory of development, which postulated the mental development was fueled by a social dynamic. He proposed that children moved from a position of egocentrism (a failure to take the other person's point of view into account) to sociocentrism (the recognition that others see the world differently than they do). Children moved from the egocentric to the sociocentric position thanks to social interaction and the challenge to younger children's ideas by the ideas of those children who were more advanced. Piaget made it clear, however, that the young children's egocentric ideas were not wrong, but merely different from those of the older children. Egocentric ideas are developmentally appropriate for young children, if not for older ones.

Stage 2: The Biological Model of Intellectual Development

In 1928 Piaget married one of his graduate students and started a family in the 1930s. Having his own infant children set the stage for the second phase of Piaget's work, the exploration of the development of intelligence in infants. During this period, Piaget studied his own three offspring. The semiclinical interview was clearly not of much use with infants who could not talk. Piaget, therefore, invented a number of ingenious experiments to test the infant's knowledge about the world. For example, he placed a cloth over a toy that the infant was playing with to see whether or not the baby would try to remove the cloth to recover the toy. If the baby removed the cloth this would be evidence that he or she had some mental representation of the toy. If the baby did not remove the cloth, but merely cried in frustration, this would be evidence that the infant had not yet attained representational thought.

During this second period of his work, Piaget elaborated a biological model of intellectual development, which he combined with the sociological model of the earlier period. He now described intelligence as having two closely interrelated facets. One of these, carried over from the earlier period, was the content of children's thinking. The other, new to this period, was the process of intellectual activity. Piaget now introduced a truly powerful idea, namely, that the process of thinking could be regarded as an extension of the biological process of adaptation.

He argued, for example, that the child who sucked on anything and everything in his or her reach was engaging in an act of assimilation, comparable to the assimilation of food by the digestive system. Just as the digestive system transforms a variety of foodstuffs into the nutriments needed by the body, so the infant transforms every object into an object to be sucked. At much higher level, whenever one classifies an object, say a dog, he or she in effect assimilates this exemplar to their more general dog concept. In so doing the particular dog is transformed into the universal, conceptual dog. At all stages of development, therefore, whenever one transforms the world to meet individual needs or conceptions, one is, in effect, assimilating it.

Piaget also observed that his infant children not only transformed some stimuli to conform to their own mental structures but also modified some of their mental structures to meet the demands of the environment. He called this facet of adaptation accommodation. At the biological level the body accommodates when, for example, its blood vessels constrict in response to cold and expand in response to heat. Piaget observed similar accommodations at the behavioral and conceptual levels. The young infant engages primarily in reflex actions, such as sucking the thumb or grasping. But shortly thereafter the infant will grasp some object and proceed to put that in his or her mouth. In this instance the child has modified his or her reflex response to accommodate an external object into the reflex action. That is to say, the infant's instinctual thumbsucking reflex has been adapted to objects in the environment. Piaget regarded this behavioral adaptation as a model for what happens at higher intellectual levels as well. Whenever one learns new facts, values, or skills, he or she is, in effect, modifying mental structures to meet the demands of the external world.

In Piaget's view, assimilation and accommodation are the invariant processes of intellectual processing and are present throughout life. Furthermore, because the two are often in conflict they provide the power for intellectual development. The child's first tendency is to assimilate, but when this is not possible, he or she must accommodate. It is the constant tension between assimilation and accommodation and the need for some form of equilibrium between them that triggers intellectual growth. For example, in the "hiding the toy experiment" described above, the six-month-old infant simply cried while the one-year-old infant lifted the cloth to reveal the hidden object. This initial upset, and failure of assimilation, thus led to the infant's construction of a mental image of the object. This new construction allows the child to solve the problem and remove the cloth from the toy. At each level of development, the failure of assimilation leads to a new accommodations that result in a new equilibrium that prepares for yet another level of disequilibrium.

Piaget published the results of these infant studies in three books, The Origins of Intelligence in the Child, The Construction of Reality in the Child, and Play Dreams and Imitation. These books continue to stimulate a wide range of investigations into the developing abilities of infants.

Stage 3: The Elaboration of the Logical Model of Intellectual Development

During the third period of his work, from the 1940s through the 1960s, Piaget explored the development of many different physical and mathematical concepts in children and adolescents. To explore the physical and mathematical conceptions of children and adolescents, Piaget returned to the semiclinical interview, but in modified form. He decided that the way to test children's level of conceptual development was to challenge their understanding of conservation, that is, their understanding that an object's physical or mathematical properties do not change despite a change in its appearance. Piaget based this methodology on the fact that scientific progress occurs when judgments of reason win out over judgments based upon appearance. The discovery of the roundness of the earth is a good example. The ancients believed that the world was flat. It was only from later observations and reasoning about the disappearance of ships on the horizon and the shadow of the earth on the moon that the perception of flatness could be overcome.

To test children's understanding of conservation, Piaget presented children with a wide array of tasks in which the child had to make a judgment on the basis of either perception or reason. Only when the child made his or her judgment on the basis of reason was the child said to have attained conservation. For example, in his studies of children's conception of number, Piaget confronted children with two rows of six pennies, one spread apart so that it was longer than the other. Young children judge the longer row to have more pennies, while older children judge both rows to have the same amount. Older children have attained the conservation of number while younger children have not.

With this conservation methodology, Piaget and his longtime colleague, Barbel Inhelder, explored how children constructed their concepts of number, space, time, geometry, speed, and much more. In this third phase of his work, Piaget introduced a logical model to explain children's attainment of conservation in different domains and at different age levels. It is this logical model of intellectual development for which he is perhaps best known. Piaget argued that intelligence develops in a series of stages that are related to age and that are progressive in the sense that each is a necessary prerequisite of the next. There is no skipping of stages. In addition, he contended that each stage was characterized by a set of mental operations that are logical in nature but vary in complexity. At each stage of development the child constructs a view of reality in keeping with the operations at that age period. At the next stage, however, with the attainment of new mental abilities the child has to reconstruct the concepts formed at the earlier level in keeping with his or her new mental abilities. In effect, therefore, Piaget conceived of intellectual development as an upward expanding spiral wherein the child must constantly reconstruct the ideas formed at an earlier level with new, higher order concepts acquired at the next level.

The first stage, infancy or the first two years of life, Piaget described as the sensori-motor period. In the first two years of life, the baby constructs elementary concepts of space, time, and causality but these are at the visual, auditory, tactual, and motoric level, and do not go beyond the here and now. At the next stage of development, the pre-operational level, children acquire the symbolic function and are able to represent their experience. Children now begin to use words and symbols to convey their experience and to go beyond the immediate. Concepts of space, time, and causality, for example, begin to be understood with terms like now and later, as well as day and night. Once the child's thought moves from the sensori-motor to the symbolic level, it has much more breadth and depth.

By the age of six or seven children attain a new set of mental abilities that Piaget termed concrete operations, which resemble the operations of arithmetic and which lift school-age children to a whole new plane of thinking. Concrete operations enable young children to reason in a syllogistic way. That may be the reason the ancients called these years the age of reason. Concrete operations enable children to deal with verbal rules and that is why formal education is usually begun at about this time. Following rules is in effect reasoning syllogistically. Consider the classic model of the syllogism.

All men are mortal.

Socrates is a man.

Therefore Socrates is mortal.

This is the same form of reasoning the child must employ if he or she is to follow the rule that says "when two vowels go walking, the first one does the talking."

When two vowels go walking the first one does the talking.

In the word ate there are two vowels and the first is an a.

In this word, a does the talking.

Concrete operations enable young children to construct their conceptions of space, time, number, and causality on a higher quantitative plane. It is during the elementary years that children are able to learn clock and calendar time, map and geographical space, and experimental causality.

At about the age of eleven or twelve young people develop yet a higher level of mental operations that Piaget labeled formal. These operations are formal in the sense that they are no longer tied to the here and now and are abstract in the sense that they can be in conflict with reality. For example, if you ask a younger child to imagine a world in which snow was black and to guess what color, in that world, Mickey Mouse's ears would be, the child would have trouble saying they were white. Adolescents who have attained formal operations have no trouble with this problem. Formal operations enable young people to understand celestial space, historical time, and multivariable causality. They can construct ideals, think in terms of possibilities, and deal with multiple variables at the same time. Formal operations move young people to a new plane of thought, which is on a level with adult thinking.

Stage 4: The Study of Figurative Thought

During the last stage of Piaget's work, which lasted until his death in 1980, Piaget explored what he called the figurative facets of intelligence. By figurative Piaget meant those aspects of intelligence such as perception and memory that were not entirely logical. Logical concepts are completely reversible in the sense that one can always get back to the starting point. The logical addition of concepts, such as "boys plus girls equals children," can be undone by logical subtraction, such as "children minus boys equals girls" or "children minus girls equals boys." But perceptual concepts cannot be manipulated in this way. The figure and ground of a picture, for example, cannot be separated because contours cannot be separated from the forms they outline. Memory too is figurative in that it is never completely reversible. Piaget and Inhelder published books on perception, memory and other figurative processes such as learning during this last period of his work.

Conclusion

Jean Piaget is clearly the giant of developmental psychology. His experimental paradigms have been replicated in almost every country in the world and with quite extraordinary comparability of results. Piaget's observations, then, are among the hardiest, if not the hardiest, data in all of psychology. No other research paradigm has received such extensive cross-cultural confirmation. In the early twenty-first century there has been a tendency of investigators to dismiss Piaget's work as passé. This would be a mistake. While it is important to challenge Piaget and to build upon the foundation he has provided, it would be wrong to discount his work without having a comparable database on which to found such a rejection. Indeed, the opposite is more likely the case, namely, that the value of much of Piaget's work both for developmental psychology education and for other disciplines is yet to be fully realized.

See also: Learning Theory, subentry on Constructivist Approach.

bibliography

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Piaget, Jean. 1951. Play Dreams and Imitation in Childhood. New York: Norton.

Piaget, Jean. 1952. The Origins of Intelligence in the Child. New York: International Universities Press.

Piaget, Jean. 1970. Science of Education and the Psychology of the Child. New York: Orion.

Piaget, Jean, and Inhelder, Barbel. 1958. The Growth of Logical Thinking from Childhood to Adolescence. New York: Basic Books.

Piaget, Jean, and Inhelder, B. 1971. Mental Imagery in the Child. London: Routledge and Kegan Paul.

David Elkind

PIAGET, JEAN
(1896–1980)

Jean Piaget, the psychologist and philosopher, was born in Neuchâtel, Switzerland. He studied zoology at the university there and in 1918 received his doctorate for a thesis on the subject of land mollusks in the Valais Alps. He then studied psychology for a year at Zürich and, from 1919 to 1921, abnormal psychology, logic, and the philosophy of science at the Sorbonne. From 1921 to 1925, he was director of studies at the Institut J.-J. Rousseau (now the Institut des Sciences de l'Éducation) in Geneva; he was its assistant director from 1929 to 1932 and became codirector in 1932. In 1925 he was appointed professor of philosophy at the University of Neuchâtel; in 1929, professor of the history of scientific thought at the University of Geneva; and in 1940, professor of experimental psychology and director of the psychological laboratory at Geneva. He served as professor of child psychology at the Sorbonne from 1952 to 1963. From 1955 to 1980 he was director of the Centre International de l'Épistémologie Génétique at Geneva. Piaget also took an active interest in international educational projects. He was director of the Bureau International de l'Éducation from 1929 to 1967 and was associated with UNESCO as its assistant director general.

Thought

Although Piaget is usually considered a psychologist working in the field of child thought, his interests were always, broadly speaking, philosophical. As a young man he read widely in philosophy, and while in Paris he studied with André Lalande and Léon Brunschvicg. Even his earliest work, which appeared between 1925 and 1932, dealt with such topics as thought, causality, moral judgment, and the development of language. His logical and epistemological interests show themselves particularly in his later studies, starting about 1937. By means of simple, although highly ingenious experiments, Piaget set out to make a detailed investigation of the way in which logical, mathematical, and physical concepts develop in the individual. He thus studied experimentally many of the concepts and principles that philosophers had discussed in the past on a purely a priori level. Piaget would say that what he was really doing in this work was reexamining the whole question of the Kantian categories. This reexamination formed for him the basis of a new discipline that he called genetic epistemology.

In a series of studies Piaget examined in some detail the development not only of abstract concepts such as classes, relations, and numbers but also of physical concepts like space, time, speed, atomism, conservation, and chance, all of which he has regarded as constructed from our behavioral activities. In starting from the facts of observable child behavior rather than from adult introspections (or sensations), Piaget differed from such thinkers as Ernst Mach, Karl Pearson, and Bertrand Russell by the importance he attached to the part played by overt activities in building up the conceptual machinery of thought. Throughout his work Piaget placed considerable emphasis on the pragmatic aspect of logical and mathematical operations, as, for example, the way we actually handle symbols and formulas. From this point of view Piaget's account bears a marked resemblance to the views of Jules Henri Poincaré and the intuitionists; the construction of number, for example, had for Piaget a definite psychological aspect.

abstract concepts

Piaget believed that logical and mathematical notions first show themselves as overt activities on the part of the child and only at a later stage take on a conceptual character. They are to be conceived as internalized actions in which things are replaced by signs, and concrete actions by operations on these signs. Rational activity occurs in the child when his trial-and-error gropings attain a definite pattern of order that may be inverted in thought. At this rational stage, if the child makes a mistake in performing a task, he is able to return to his starting point. This characteristic of thought that enables us to reverse a train of ideas or actions Piaget calls "reversibility." It is the basis of our ability to perform mental experiments, as well as the psychological foundation of the deductive process.

Piaget contended that the more elementary forms of logical behavior in which the child compares, distinguishes, and orders the objects around him are largely concerned with the creation of concrete classificatory and relational systems. It is from these systems that we develop our later, more abstract, logical and mathematical modes of thinking. Piaget would rather not speak of the intuition of number before the child has developed logical concepts of invariance and has thereby grasped the operation of reversibility. The transition to number occurs in the child just when his activities of classifying and ordering objects take on the form of simple logical systems. What emerges from Piaget's experimental researches is that numerical concepts in their psychological development are ultimately based on simple logical notions. There is thus some resemblance between the way number comes to be constructed in a child's thought and the attempt on a purely normative plane by Russell and others to define number in logical terms.

physical concepts

Among the other concepts studied by Piaget, those of time and space are of particular philosophical relevance. Immanuel Kant, for example, believed that these concepts were objects of an a priori intuition. Piaget, however, found that the abstract notion of time arises at a relatively late stage; at first time is connected with space. For example, the child first confuses the notion of age with that of height or other visible signs of age. As far as space is concerned, his ability to make spatial judgments is initially fairly rudimentary. He can differentiate between open and closed figures but has difficulty in distinguishing one shape from another. He is also incapable of imagining a perspective other than his own. Only at a later stage is he able to take account of several relations at once (before and behind, right and left) and to coordinate them into a general system of perspectives.

perception

For Piaget learning played an important part not only in the elaboration of intellectual structures but also in the field of perception. It is this that distinguishes his view from that of the Gestalt psychologists. For the latter, the perceptual constancies of shape and size belong directly to the perceived objects and are independent of age and ability. For Piaget, however, perception of figures is built up as a result of a series of random eye and other muscular movements, which are gradually corrected. The young child does not attribute a constant size or even identity to the objects around him. Piaget believed that the logical forms of activity that emerge in child behavior, namely classifying, relating, and so forth, arise as a result of his trial-and-error activities.

Piaget's views on perception have certain philosophical implications. In the past, he points out, philosophers have assumed a definite psychology of perception in their epistemologies. A good example of this is John Locke's sensationalism, in which it is assumed (1) that empirical facts are passively given in perception and (2) that they correspond to a certain range of linguistic expressions that designate them. For Piaget, however, even the notion of an object, one of the simplest forms of perceptual invariants, requires a definite learning process. Before the child is able to use linguistic expressions to refer unequivocally to definite objects, he must first have developed concrete classificatory and relational activities. Even the simple statement, "This is green," implies the acquisition of such skills and hence cannot be regarded as a reference to a simple perceptual datum. When we talk intelligently of green, this presupposes that we have learned to classify objects according to their color and to differentiate one color from another.

behavior and logic

Piaget's work might be dismissed as philosophically irrelevant by philosophers of a Platonic turn of mind. It might be said that philosophical discussions of conceptual thinking are largely concerned with questions of validity and not with questions of origin. Piaget does not deny that logical notions as they appear in purely formal discussions differ from those occurring in ordinary thought. However, he asserts (1) that even our simpler kinds of intellectual performance have a logical character about them, which we can study formally, and (2) that when the logician constructs logical systems, performs deductions, tests for validity, and so on, his logical behavior can be studied in the same direct way as that of the child or unsophisticated adult. Piaget also believed that it may be illuminating to compare the simpler logical structures inherent in our behavior with the purely formal systems constructed by the logician, as we may find some continuity between them.

See also Brunschvicg, Léon; Intuitionism and Intuitionistic Logic; Kant, Immanuel; Mach, Ernst; Number; Pearson, Karl; Perception; Poincaré, Jules Henri; Psychology; Russell, Bertrand Arthur William.

Bibliography

works by piaget

Piaget was a prolific writer, and among the numerous volumes he wrote, the following have a specifically logical or philosophical character:

Le jugement et le raisonnement chez l'enfant. Paris, 1924. Translated by M. Warden as Judgment and Reasoning in the Child. New York: Harcourt Brace, 1928.

Le langage et la pensée chez l'enfant. Paris, 1924. Translated by M. Warden as The Language and Thought of the Child. New York: Harcourt Brace, 1926. 2nd ed. translated by M. Gabain. London, 1932.

La représentation du monde chez l'enfant. Paris: Alcan, 1926. Translated by J. Tomlinson and A. Tomlinson as The Child's Conception of the World. New York: Harcourt Brace, 1929.

La causalité physique chez l'enfant. Paris, 1927. Translated by M. Gabain as The Child's Conception of Physical Causality. New York: Harcourt Brace, 1930.

Le jugement moral chez l'enfant. Paris: Alcan, 1932. Translated by M. Gabain as The Moral Judgment of the Child. New York: Harcourt Brace, 1932.

La genèse du nombre chez l'enfant. Paris, 1941. Written with A. Szeminska and translated by C. Gattegno and F. M. Hodgson as The Child's Conception of Number. New York: Humanities Press, 1952.

Le développement des quantités chez l'enfant. Paris, 1941. Written with B. Inhelder.

Le développement de la notion du temps chez l'enfant. Paris: Presses Universitaires de France, 1946.

Les notions de mouvement et de vitesse chez l'enfant : Paris: Presses Universitaires de France, 1946.

La représentation de l'espace chez l'enfant. Paris: Presses Universitaires de France, 1948. Written with B. Inhelder and translated by F. J. Langdon and J. L. Lunzer as The Child's Conception of Space. New York: Humanities Press, 1956.

La géometrie spontanée chez l'enfant. Paris: Presses Universitaires de France, 1948. Written with B. Inhelder and A. Szeminska and translated by E. A. Lunzer as The Child's Conception of Geometry. New York: Basic, 1960.

La genèse de l'idée de hazard chez l'enfant. Paris: Presses Universitaires de France, 1951.

De la logique de l'enfant à la logique de l'adolescent. Paris: Presses Universitaires de France, 1955. Translated by Anne Parsons and Stanley Milgram as The Growth of Logical Thinking. New York: Basic, 1958.

La genèse des structures logiques elementaires. Paris, 1959. Written with B. Inhelder.

works on piaget

There have been few philosophical discussions of Piaget's work, but W. Mays, "The Epistemology of Professor Piaget," in PAS (London, 1953–1954) compares his epistemology with the views of contemporary philosophers. C. Parsons in "Inhelder and Piaget's 'The Growth of Logical Thinking: II.' A Logician's Viewpoint," in the British Journal of Psychology (1960), criticizes Piaget's logic from a theoretical standpoint.

John H. Flavell in The Developmental Psychology of Jean Piaget (Princeton, NJ: Van Nostrand, 1963) gives a good summary of Piaget's work from a psychological point of view. The book contains an excellent bibliography of primary and secondary sources. W. Mays, "How We Form Concepts," in Science News (1954) gives a simple introduction from a more philosophical viewpoint.

K. Lovell in The Growth of Basic Mathematical Concepts in Children (London, 1961) provides an introduction to Piaget's ideas from an educational standpoint. Z. P. Dienes in Building up Mathematics (London, 1960) shows how Piaget's work has influenced the introduction of new methods in the teaching of school mathematics.

other recommended works

Battro, Antonio M. Piaget: Dictionary of Terms. New York: Pergamon Press, 1973.

Boden, Margaret A. Jean Piaget. New York: Viking Press, 1980.

Bringuier, Jean Claude, and Jean Piaget. Conversations with Jean Piaget. Chicago: University of Chicago Press, 1980.

Elkind, David. Child Development and Education: A Piagetian Perspective. New York: Oxford University Press, 1976.

Elkind, David, and John H. Flavell, eds. Studies in Cognitive Development: Essays in Honor of Jean Piaget. New York: Oxford University Press, 1969.

Furth, Hans G. Piaget and Knowledge: Theoretical Foundations. Englewood Cliffs, NJ: Prentice-Hall, 1969.

Ginsburg, Herbert, and Sylvia Opper. Piaget's Theory of Intellectual Development. 3rd ed. Englewood Cliffs, NJ: Prentice-Hall, 1988.

Kegan, Robert. The Evolving Self: Problem and Process in Human Development. Cambridge, MA: Harvard University Press, 1982.

Murray, Frank B., and Millie Corinne Almy. The Impact of Piagetian Theory: On Education, Philosophy, Psychiatry, and Psychology. Baltimore: University Park Press, 1979.

Piaget, Jean. The Essential Piaget, edited by Howard E. Gruber and J. Jacques Vonèche. Northvale, NJ: J. Aronson, 1977, 1995.

Piaget, Jean, and Bäbel Inhelder. The Child's Conception of Space. New York: W. W. Norton, 1967.

Piattelli-Palmarini, Massimo, ed. Language and Learning: The Debate between Jean Piaget and Noam Chomsky. Cambridge, MA: Harvard University Press, 1980.

Wolfe Mays (1967)

Bibliography updated by Michael J. Farmer (2005)