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Psychology (Classical)


A term meaning the study of the soul, coined from the Greek ψυχή (soul) and λόγος (concept) by R. Goclenius (15471628). The branch of knowledge it designates has taken on a distinctive form since 1850, but its beginnings can be traced to the ancient Greeks. Aristotle is generally considered the "Father of Psychology," both because he wrote extensive treatises on expressly psychological questions and because he grounded his studies as a natural science on a broad empirical base. Nevertheless, even before Aristotle, the Greek thinkers were speculating on psychological questions.

Development of the Concept. For the Greeks the study of living organisms was only one part of the general study of nature. aristotle distinguished between natural bodies that are not moved except by others, and natural bodies that are able to move themselves. The latter, living things including plants, brute animals, and men, form the subject of a special part of the science of nature. He undertook to classify living things, to examine their structures and functions, and to formulate definitions of the principle within them by which they were able to move themselves, which he called the soul. His treatise De anima (On the Soul) served as a fundamental text in psychological science for over 2,000 years.

After Aristotle, psychology developed mainly along three lines. A few Greek and Arabian philosophers wrote fresh treatises on matters that Aristotle had touched only lightly or not at all, but most contented themselves with writing commentaries on the master's works, or commentaries on other commentaries. The Greek and Arabian physicians contributed shrewd insights from their clinical observations, but introduced errors also. Finally, moral philosophers and the Christian Fathers enlarged the scope of descriptive psychology, especially in the areas of human passions, habits, attitudes, and will, in treatises whose main focus was the living of the good life and the avoidance of vice.

In the 12th and 13th centuries, when the universities began to flourish in Europe, psychology experienced a new vigor. By this time the study of plants and animals had been largely separated from the study of human life, and a new purpose animated philosophers. Their aim was to formulate a systematic science of human nature, culminating in a definition of the human soul and its relationship to the body. The medieval philosophers drew heavily on the Greek, Arabian, and Christian traditions, especially on plato and Aristotle, augustine, gregory i (the great), john damascene, gregory of nyssa, aver-roËs, and avicenna, but they did not hesitate to adapt the ideas they used to the demands of their own systems of thought.

Method. The psychology of St. thomas aquinas exemplifies the medieval approach to the subject. He followed Aristotle in holding that the study of living things was a special part of the science of nature, but his interests were directed almost exclusively to human psychology, He maintained that as a science it should be based on strictly empirical data, but he was willing, as were all philosophers of the day, to speculate on the basis of these data, sustaining conclusions that could not themselves be demonstrated by direct evidence. He accepted data both from observation and from introspection.

Observation was mostly a matter of general and common experience; controlled and systematic observation was not yet part of the scientific method. The procedure was first to determine the most general principles governing an area of investigation, and then to divide the matter into parts and determine the principles of each subdivision, and so on. Thus, if the purpose of the investigation were scientific knowledge of sensation, the first step would be the definition of the nature of knowledge in general. Then the difference between intellectual and sense knowledge would be established. Next would come the distinction between internal and external sensation, and then the specific kinds of internal and external sensation, and finally the variety of modes or functions of which each specific sense is capable. In the investigation, search would be made for all the causes governing the nature of the given object at each level of generalization. The causes include the final cause or purpose, the efficient cause or agent, the formal cause or specific feature, and the material cause, or elements out of which the thing was made (see demonstration). When the four causes had been determined, the investigation would have achieved its purpose.

The validity of this procedure rests on the accuracy and thoroughness of the empirical data on which it is based, and the rigor of the logical formulations and deductions. The method is successful in establishing the general principles and canons of psychology and in framing its broader conclusions, but for more detailed knowledge and for practical applications of knowledge, the facts of general experience must be augmented and refined by data from controlled observations, experiments, clinical experience, and the variety of techniques being evolved in contemporary research.

Contents. Scholastic philosophers are generally agreed on most of the major theses concerning the human soul and human nature, although they differ among themselves on points of interpretation, emphasis, and approach.

Life. They define life as self motion, that is, the capacity of an organism to move itself from potentiality to activity. From another point of view, the distinctive feature of vital operations is their immanence, that is, the characteristic of self-perfecting action that is involved in living activity. In a broad sense, for instance, nourishment perfects the organism nourished. In a stricter sense, knowledge is the perfection of the mind knowing. Both characteristics, i.e., self movement and immanence, imply that living things exist and operate on a higher scale than inorganic bodies, for living things move themselves to full perfection and maturity through their interactions with other bodies, whereas inorganic bodies lose their energies and even their existence when they interact with others.

The Soul. The principle of life in living things is called the soul. In essence, the soul is the factor in virtue of which living bodies have their special organization, and thus are able to function in special ways. The soul is not necessarily immaterial or spiritual; in animals and plants it is purely material. Only in man is there evidence of its transcending purely material being.

Since living things operate through parts that have special functions (organs) and yet are single units whose various operations are directed to the survival, development, and propagation of the whole, the soul, as the principle of the whole, is conceived by Thomists as something essentially simple but capable of several distinct operations, fewer in lower forms of life and most numerous in man. These capacities for distinct operations are called faculties of the soul. Other scholastics acknowledge the faculties, but argue that there is more than one principle of life, or soul, in higher organisms.

Scholastics generally agree on five genera of vital faculties: vegetative faculties, powers of local movement, sensitive faculties, intellective faculties, and powers of appetition. They generally agree also in assigning three specific faculties to the vegetative order, viz, nourishment, growth, and reproduction. The study of these vegetative processes would probably have been given scant attention if the requirements of a philosophical system alone were in question. But scholastics devoted considerable thought to processes such as reproduction or birth, because some of the key mysteries in Christian revelation were couched in these terms. The Second Person of the Blessed Trinity is born of the Father, and again born of the Virgin Mary. A baptized person is reborn of water and the Holy Spirit. To interpret these mysteries, scholastics wanted precise knowledge of the natural process of birth, and thus this topic became a matter of prime interest.

Sensation. In considering the category of sensation, scholastics distinguish between external and internal senses, but differ on their number. Most are agreed on five external senses, with the sense of touch being a compound sense attaining several distinct objects, such as temperature, resistance, pain, and pleasure. After St. Thomas, internal senses were generally held to be four, viz, the central sense, imagination, memory, and the cogitative power. But some 20th-century scholastics question the existence of the central sense, the cogitative power, or both.

All scholastics make a sharp distinction between the senses, which know concrete and singular objects, and the intellect, which knows objects in abstract and universal forms. They divide appetition along the same lines as knowledge, i.e., into sense appetites and the intellectual appetite or will, although there is some disagreement over details.

Knowledge. A key point in any psychological theory is the theory of knowledge, i.e., the precise explanation of the operation by which man knows objects distinct from himself (see knowledge, theories of). It is a curious fact that outside the scholastic tradition no attempt is made to face the full requirements of an adequate theory of knowledge. Much is written by philosophers concerning the validity of knowledge acts and concerning the logical force of knowledge processes, and more is written by psychologists on the acquisition of knowledge and on its physiology, but the phenomenon whose validity, processes, acquisition, and physiology are under investigation is itself left undefined. According to the traditional theory of knowledge the objects of knowledge are the forms of things, namely, all the determinants that make a thing to be what it is. The process of knowledge involves the reception of these forms into the knowing powers of the knower, but it is a reception that is somehow immaterial (see knowledge, process of). Unlike the process by which a stone is heated (receiving the form of heat from another) or wax is imprinted by a seal (receiving the shape of the seal), the form received in a knowledge act is undetectable in the knower and known to be present only by himself. Hence it follows that the form is present in a way unlike the way physical forms are present, and hence it is termed "immaterial," meaning not received in the knower as a simple physical effect. Then, since materiality is the reason two like forms are distinct from each other, the immaterial presence of the form in the knower leaves it somehow indistinct from the form in the thing known. Thus the objectivity that is an experiential feature of knowledge acts is capable of reasonable explanation.

This theory of knowledge purports to be the fundamental explanation of all acts of knowledge, whether of sensation or of intellection. The difference between these two operations lies in the difference in the mode of the form received. In sensation the concrete, individual forms of an object are received, viz, its visible, palpable, audible, etc., features, as, being present, they impress themselves on the subject, or as they are later recalled. In intellection the mind attains the abstract, and hence universal, ideas drawn from the sensible experience of its objects.

The clear-cut distinction that scholastics place between sensation and intellection presents them with a problem that a purely materialistic or a purely idealistic psychology does not face. They must explain how the mind can form universals, and abstract ideas of concrete and singular objects. To account for this process of abstraction, an agent intellect is posited, as an active power of the mind by which intelligible species are formed out of the sensible images of things, and then impressed on the knowing intellect. The intellect then knows its objects as the universal, abstract essences, or definitions, of the concrete, singular objects from whose sensible images it has drawn its knowledge.

Appetition. In scholastic psychology, the appetitive processes are, functionally subsequent to knowledge processes. They are responses to known objects, in the form of inclinations toward good objects and away from evil objects; At the sense level, appetite begins with the sensations of pain and pleasure, and operates to orient the organism toward pleasant objects and away from painful objects. This simple pleasure-pain appetite is called the concupiscible appetite. In cases of emergency, a second sense appetite, the irascible appetite, operates to overcome difficult objects.

The highest appetite in man is the rational appetite, called the will, which operates to seek out the reasonable good and avoid the reasonable evil. The will follows whatever the intellect proposes as good, and whenever the intellect proposes several goods, none of which is compelling, the will is free to elect among them (see free will). The will is the highest motive force in man, controlling his other powers, although not all to the same extent. It commands overt behavior "despotically," as the scholastics say, but has only "political" control over the lower appetites and knowledge faculties. In comparing the intellect and the will from the point of view of excellence, St. Thomas and Thomists argued for the superiority of the intellect; duns scotus and his followers urged the superiority of the will; other scholastics held for an equality of excellence (see intellectualism; voluntarism).

Man. The process of determining the elements of human nature, namely, body and soul, and the specific faculties with which it is equipped is the analytic part of scholastic psychology. The synthetic part is the definition of the whole human composite made up of these elements and the assessment of the structure of human nature. (see man, 2.)

In the classic definition, man is a rational animal, that is, an animal like other animals, but distinct by having the power of universal, abstract reason, and all that follows from it. One of the principal conclusions scholastics draw from this is that the soul of man is spiritual and therefore immortal, that is, that after death the vital principle of the human composite does not decay or corrupt or pass away, but persists in existence and in vital operation (see immortality). The question then arises as to how the union of a spiritual principle and a physical body is to be conceived. At one extreme, the soul was conceived as something quite separate from the body and dwelling in the body like a man in a prison, or like a driver in a machine. Another opinion, deriving from the Arabian philosophers, was that the intellect was a separate entity, one for all men, in whose ideas all men, although physically distinct, somehow participated. St. Thomas fought vigorously for the concept of the unity of the human compositeperhaps in the field of psychology this was his major preoccupationinsisting that the soul and the body were incomplete principles that when joined together formed one, single entity, the soul being the determining element and the body the element determined (see soul, human,4). Therefore, even though the soul could exist and act after death, it was in an extreme state of violence, and, naturally speaking, as miserable as it could be. After St. Thomas, scholastics did not generally hold opinions that separated soul and body as radically as those mentioned above, but some scholastics, for instance, Duns Scotus and F. suÁrez, held for more than one vital principle in man, the rational soul being his major soul, while other vital forms gave him lower levels of life.

While all men, in virtue of having rational souls, are essentially alike, different men can have the various powers of life in different degrees and different proportions; therefore there is a basis for asserting various diversities among men. Some of these differences are inbornthe scholastics pointed out the obvious differences of the two sexes and supported the classical theory of temperament according to which the different proportions of the basic humors in the human body affect men psychologically as well as physically. They maintained that individuals differ in native talent and psychological tendencies, so that some men are naturally noble and born to rule whereas others are naturally base and more fit to serve.

Given the inborn differences among men, the disparities between one man and another can be increased by acquired differences. According to St. Thomas, who developed much of his psychology of habit formation within the context of moral philosophy and theology, an acquired habit may be partly natural, as coming from native propensities, or purely acquired, by repeated acts. The intellect and will are the subjects of the most numerous and important habits, but the sense appetites can also be affected by habit formation. He did not consider the senses themselves and the physical functions and organs apt for habit formation except in a secondary and ancillary way.

Relation to Other Disciplines. The traditional psychology of the scholastics, which is today called philosophical psychology, or the philosophy of man or of human nature, is still considered a part of the general science of nature, or natural philosophy (see philosophy of nature). The principles that explain bodies in general, and the laws that govern them, are applicable to living bodies as well, and in living bodies often find their clearest exemplification.

When the scholastic psychologies were being formulated, the sphere of living organisms was set apart as one area of investigation. Today this area is studied in numerous more or less distinct branches of science, e.g., biology, psychology, zoology, botany, physiology, taxonomy, morphology, genetics, embryology, ecology, and evolution; but the basic unity of these diverse sciences is gradually regaining recognition in studies under the title of life sciences. The relation of these life sciences, and especially of modern psychology, to traditional psychology is a matter of dispute among contemporary scholastics. At the level of broad and basic principles, traditional psychology and the modern sciences often raise the same kind of questions for discussion. At the level of empirical research, experimentation, and formulation of data, the relationship is not so clear. Some hold that rational and empirical psychologies are distinct and unrelated, others hold that they are distinct and complementary, while still others hold that they are not distinct sciences but stages or grades of development within one science.

In relation to other philosophical disciplines, traditional psychology holds a key position. Discerning and defining the acts and processes of the intellect, it supplies the materials of the sciences of logic and epistemology. It is necessary for the science of metaphysics, which reaches the highest causes of things, because "if the nature of the possible intellect were unknown to us, we could not know the order of the separated substances" (St. Thomas Aquinas, De anim. 1.7). By defining human acts, analyzing the conditions of free and deliberate behavior, and elucidating the possible goals and the limits human nature can achieve, psychology provides the elements of study with which moral philosophy or ethics deals. Consequently, psychology enters into all the special parts of ethics, into politics, economics, social sciences, education, etc.

The relationship of psychology to the theological disciplines is equally vital. Much of scholastic psychology is found in the context of theological discussion, in which the concepts and conclusions of psychological investigation are brought to bear to elucidate the terms of the mysteries of revelation. The concepts of the human soul and its powers of intellect and will are basic to concepts of God and the angels and their intellects and wills. The Trinity and its processions and relations are understood in terms of analogies with the intellect and intellection and love. Man's rebirth in grace, his growth in grace, the nature of the theological and infused moral virtues, man's destiny in terms of his divine vocation, the gifts and fruits of the Holy Spirit, and the beatitudes are all understood by comparison with psychological realities. It can be asserted without hesitation that an understanding of the contents of rational psychology is an essential part of the understanding of all rational philosophy and Christian theology.

See Also: soul, human; man, 2, 3.

Bibliography: thomas aquinas, Aristotle's De Anima and Commentary of St. Thomas Aquinas, tr. k. foster and s. humphries (New Haven 1951); The Soul, tr. j. p. rowan (St. Louis, Mo.1949); In Aristotelis libros De sensu et sensato, De memoria et reminiscentia commentarium, ed. r. m. spiazzi (3d ed. Turin 1949); Summa theologiae, tr. Eng. Dominican Fathers (New York 1947), 1a, 7592, on the structure of human nature; 1a2ae, 117, on goals and the acts of the will; 1a2ae, 2260, on passions and habits; Truth, tr. r. w. mulligan et al., 3 v. (Chicago 195254), questions 10, 12, 13, 1517, 22, 2426; On Aristotle's Love and Friendship, tr. p. conway (Providence, RI 1951), books 8 and 9 of the Commentary on the Nichomachean Ethics. aristotle, Works, ed. w. d. ross, 12 v. (New York 190852), v.3 De Anima. r. e. brennan, Thomistic Psychology (New York 1956). j. f. donceel, Philosophical Psychology (2d ed. New York 1961). h. d. garden, Introduction to the Philosophy of St. Thomas Aquinas, tr. j. a. otto, 4 v. (St. Louis, MO 1956). É. h. gilson, The Spirit of Medieval Philosophy, tr. a. h. c downes (New York 1936). j. gredt, Elementa philosophiae Aristotelico-Thomisticae, ed. e. zenzen, 2 v. (13th ed. Freiburg 1961), v.1. e. hugon, Cursus philosophiae Thomisticae (Paris 1905) v. 34, Philosophia naturalis: Biologia et psychologia; metaphysics psychologica. g. p. klubertanz, The Philosophy of Human Nature (New York 1953). o. lottin, Psychologie et morale aux XII e et XIII e siècles, 6 v. in 8 (Louvain 194260), v.1 Problèmes de psychologie. m. maher, Psychology (9th ed. New York 1921). j. maritain, Distinguish to Unite, or The Degrees of Knowledge, tr. g. b. phelan (New York 1959). t. v. moore, The Driving Forces of Human Nature and Their Adjustment (New York 1948). a. c. regis, St. Tomas and the Problem of the Soul in the Thirteenth Century (Toronto 1934). j. e. royce, Man and His Nature (New York 1961). j. wild, Introduction to Realistic Philosophy (New York 1948).

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