Consciousness has three distinct meanings in the modern world. First it refers to immediate subjective experience. Second, it is the source of immediate and certain knowledge of mental states. For example, if I am in pain, I am conscious of pain and certain of this knowledge of my mental state. Third, it is self-consciousness, a concept of the self that answers the question "Who am I"?
From the seventeenth to the later part of the nineteenth century, the first two meanings of consciousness were indistinguishable and often joined by the third meaning: The presence of immediate private experience was assumed, and infallible truths about states of mind and personal or collective identities were derived from it. Since the later nineteenth century, these three ideas of consciousness have been distinguished from each other and subjected separately to criticisms and doubts.
The etymology of consciousness is derived from the Latin con (with, together) and scire (to know). When Romans shared particular knowledge, they had con-sciousness. Sharing knowledge with oneself is the etymological source of conscience. In medieval Latin, for example in the works of St. Thomas Aquinas (c. 1224–1274), consciousness came to mean a knowing subject, as distinct from an unconscious person or a plant. However, the first two modern senses of consciousness were introduced largely by René Descartes (1596–1650).
Consciousness in Modern Philosophy
Since its inception in the seventeenth century, the history of the modern idea of consciousness is intertwined with the history of the idea of science and the scientific worldview. Consciousness has been on the rims of the scientific worldview, at once a challenge to the applicability of the scientific method for understanding consciousness, and an alternative possible source of knowledge, more certain than scientific empirical knowledge that must rely on the senses.
The Cartesian revolution.
When Descartes initiated the discussion of consciousness in Europe, it was against the backdrop of the scientific revolution of the seventeenth century. Science presented then a materialist and mechanistic worldview. Pre-Newtonian science considered the universe to be composed of material particles that generate motion and change by direct physical interaction and transmission of force, much like clockwork or a billiard game. Descartes proposed to distinguish humans from artificial or organic machines (brutes) by the presence of mind, language, reason, and consciousness. Descartes believed that consciousness provides an intimate and certain source of knowledge, superior to empirical knowledge that is founded on the fallible and often misleading evidence of the senses. What we take as our sensory input may be a dream; we may be "brains in a vat," as later epistemologists put it. But conscious introspection can provide sure knowledge about ourselves that is independent of the senses. For example, Descartes's famous saying, cogito ergo sum, "I think, therefore I am," suggests that any act of thinking implies the presence of a thinker, a person, and therefore self-knowledge of personal existence is certain. Descartes then divided the universe into material things, res extensa, that exist in space, and res cogitas, consciousness, a mind that thinks but has no material extension. The resulting duality of mind and body came to be known as dualism. Dualists must explain how mind and body interact in the person despite their qualitative differences, and respond to attempts to reunify mind and body in monistic philosophic systems that consider everything to be either ideal, part of immaterial consciousness, or material, so that consciousness is part of the material world that science describes—brain states, for example.
The phenomenological tradition.
Immanuel Kant (1724–1804) revolutionized philosophy by distinguishing the introspective study of the structure of pure consciousness as the subject matter of philosophy, distinct from the study of nature, the subject matter of science. Kant studied how any sensory input must appear in consciousness, in what he called the categories such as time, space, and causal order. However, Kant also concluded that while philosophical introspection may offer an infallible knowledge of the structure of consciousness, there could never be knowledge of the world as it is independent of consciousness.
Georg Wilhelm Friedrich Hegel (1770–1831) attempted to reunify consciousness with the world in an idealist monistic scheme according to which the world is a spirit, and our consciousness is that part of the world that can achieve self-consciousness. Consciousness, then, is what determines being, what happens to exist materially at any moment.
In his 1874 Psychology from an Empirical Standpoint, Franz Brentano (1838–1917) introduced the thesis that all conscious states are intentional. We experience the world against the background of our intentions, manifested in a sense of meaningfulness or meaninglessness. For example, my current conscious state includes my thoughts about this entry, vision of a computer screen, the sounds of a Mahler symphony in the background, and so forth. All these experiences are imbued with meaning against my intentions, to write a comprehensive and informative entry, to enjoy listening to my favorite composer, and so on. Had my intentions been different, say to earn a lot of money and to become better acquainted with contemporary rap, my state of consciousness, though including the same sights and sounds, would have been different and the experience much less meaningful.
Brentano taught at the University of Vienna. Among his most remarkable students were both Edmund Husserl (1859–1938) and Sigmund Freud (1856–1939). The first founded the philosophical school of phenomenology, the culmination of the tradition that considered consciousness to be the subject matter of philosophy and direct introspection the sure method. The second extended intentionality to unconscious states, but also shifted the focus of intellectual discourse from consciousness to the unconscious.
Husserl's phenomenology is the last great school of philosophy to attempt to found certain knowledge on introspection of our consciousness. Husserl thought that with the scientific revolution, people lost awareness of pristine and immediate consciousness, which has been emptied of meaning because they objectify, abstract, and conceptualize. Husserl sought to recapture and philosophically analyze this immediate consciousness. Husserl called his method epoché, the suspension of belief in the distinction between subjective and objective phenomena that allows immediate consciousness to "appear." Within epoché, consciousness appears full of meaning, prior to conceptualization, and so the philosopher who follows Husserl's method will be able to analyze the universal aspects of consciousness. Husserl called what should appear to anybody who goes through epoché the "life-world." Husserl's description of the life-world he discovered may be interpreted as a reaction against increasing modernity, urbanization, and loss of traditions and security in Europe in the early twentieth century; against the loss of a pristine bucolic world of farmers rooted in their land; and against the growing gap between the scientific worldview of matter and energy, galaxies and atoms, and the human perspective on the world of earth and sky, flowers and friends. Husserl's method of epoché proved susceptible to personal biases and so generated accounts as different from each other as those of Martin Heidegger and Emmanuel Levinas (1906–1995). Husserl was also criticized for not considering possible differences between human consciousness in different historical eras or cultures, though such philosophical anthropology has never been his purpose.
The gap between the modern scientific worldview and human point of view also spurred the explorations of the French philosopher Henri-Louis Bergson (1859–1941). Bergson was particularly interested in our consciousness of time. Physics (except for Newton's law of entropy, which stipulates increasing disorder in the universe in the direction of time) is indifferent to the direction of time from past to future. Einsteinian relativity considers time as a dimension that can be stretched or compressed in relation to gravity and velocity. Our conscious experience of time is quite different. Bergson attempted to distinguish our conscious experience of time as a continuous duration from its scientific divisibility into moments.
At the same time, "stream of consciousness" novelists such as Henry James, Arthur Schnitzler, Virginia Woolf, and especially James Joyce in Ulysses explored consciousness and time through a narrative method that attempted to record everything that goes through their protagonist's minds.
Freud broke with the philosophic tradition that had identified the mental, the mind, with consciousness and consequently considered the introspective study of consciousness as the source of certain knowledge. Freud divided our mental lives into the conscious and the unconscious. Freud's unconscious is composed of desires that are suppressed, expelled from the conscious self because they are unacceptable or too painful especially in connection with suppressed memories of traumas suffered especially during early childhood. Still, though unconscious, these motives and memories express themselves in dreams, neurotic obsessive symptoms, phobias, slips, jokes, sublimated art, and under hypnosis. It is impossible to learn of the content of the unconscious by direct introspection, but indirectly, through free association and the symbolic interpretation of dreams.
Freudian psychoanalysis offered to cure neurotics through recollection of the suppressed memories of the events that caused the suppression of desires. This "catharsis" should increase consciousness at the expense of the unconscious. Since the suppressed memories are painful, people devise a variety of defense mechanisms to avoid confronting them consciously. Consequently, the Cartesian tradition of gaining certain knowledge through introspection collapsed: introspection is useless for gaining access to the unconscious, indeed it may be misleading because of defense mechanisms. The correspondence between one's thought and thoughts about thoughts (self-consciousness) has come under even greater criticism since Freud. For example, Gilbert Ryle in his Concept of Mind (1949) argued that introspection, inward perception of mental entities, is fallible and incomplete.
In a larger historical context, Freud responded to the rise of irrational political forces in Europe that appealed to unconscious, uncontrolled, and ultimately destructive mental forces that eventually dominated the middle of the twentieth century in Europe. Freud wished to devise a method that would bring the unconscious under the control of the rational conscious. Other trends within depth psychology, art, and politics sought quite on the contrary to release the unconscious powers, dreams, and nightmares and allow them to dominate the conscious. Younger psychoanalysts like Carl Jung (1875–1961) and Jacques Lacan (1901–1981) offered alternative characterizations of the conscious and the unconscious.
Contemporary Philosophy of Mind
The middle of the twentieth century witnessed a decline in discussion of consciousness. The research programs associated with the chief intellectual trends of the time had no fruitful implications for our understanding of consciousness: Martin Heidegger (1889–1976) directed phenomenology toward ontology and hermeneutics; structuralism and poststructuralism studied texts and languages; Marxism considered subjective consciousness to be derived from the more basic and objective material relations of production; in psychology, behaviorism ignored consciousness, while in philosophy logical positivism ignored in principle what cannot have immediate operational, empirical, effects. Behaviorism and positivism, the dominant schools respectively in academic psychology and philosophy until the sixties, ignored the study of consciousness because it could not be reduced to observable behavior or empirically verified. Since the study of private consciousness was beyond the methods associated with the research programs of either school, it was left to literature and mysticism.
In the last few decades of the twentieth century several intellectual developments led to refocusing of philosophy, especially in English-speaking countries, on the problem of consciousness. The failure of philosophical positivism to explain actual scientific theories that contain nonobservable concepts such as energy, and the uselessness of behaviorism for the solution of many problems in psychology in comparison with alternative research programs, spurred an academic search for more fruitful research programs and a return to the problem of consciousness.
Advances in neurology; the physical study of the brain, using brain scanning, rare cases of localized brain damage, and so forth; the discovery of genetic causes for a variety of mental illnesses; and research into the effects of drugs on the brain allowed scientists for the first time to offer physiological, material explanations to a variety of states of consciousness. At the same time, advances in computer technology generated advanced forms of artificial intelligence. For the first time, humans created artifacts that appeared more intelligent than themselves. This led to a reexamination of popular conceptions of the distinctive essence of humanity. If not intelligence, perhaps consciousness could distinguish us from our machines?
Philosophers, scientists, and writers wondered about the prospects for conscious artificial intelligence, and hence about the meaning of consciousness. The knowledge acquired about complex information processing through the analysis of systems, such as those of artificial intelligence, prepared expectations for attempting to understand the mind as a complex information-processing system, and consciousness in those terms. These developments have led to the founding of the new, yet controversial, "cognitive science"—"cognitive silence" for its detractors.
The discussion of consciousness in recent philosophy of mind may be traced to Thomas Nagel's (1974) groundbreaking reformulation of the mind-body problem, the relation between the physical and the mental. Nagel asked whether the physical-material external description of brain states could ever explain the mental internal experience of consciousness. Nagel argued that there is and always will be an "explanatory gap" between our consciousnesses and what a science of the mind may explain, however sophisticated it becomes. It will never be able to explain "what it is like" to have specific points of view, for example, what it is like to be a bat, hang upside down from the ceiling, and sense radar rays.
Much of the subsequent debate centered on reasons for affirming or denying the existence of the explanatory gap. Dualists like Nagel and John Searle suggested that though consciousness is a natural phenomenon, we lack the concepts and theories to close the explanatory gap. Eliminativism claims that there is no explanatory gap because consciousness does not exist; it "eliminates" the explanatory gap by eliminating consciousness. Daniel C. Dennett (1991), following Julian Jaynes (1976), claimed that consciousness is a cultural construct that emerged in ancient Greece.
Functionalists such as Australian philosopher D. M. Armstrong and Hilary Putnam proposed to characterize states of consciousness by their causes and effects, rather than by their internal properties. Physicalists claim that ultimate reality is material and described by physics. Both consider the explanatory gap as a problem of reduction of the mental to the physical. They recognize that there is at present an explanatory gap, but they believe that it may be possible to close it through a successful scientific reduction of the mental to physical theories. Some advocated that such a reduction will prove that a type of conscious state such as being in love or seeing red will be reduced to a physical or chemical description of a brain state. Others, such as Patricia and Paul Churchland, envisioned the reduction of what they call "folk psychology" to an advanced neuroscience along the lines of the reduction by chemical theories of ordinary descriptions of chemical interactions to a small number of types of basic elements and the laws that govern their interactions. Such a reduction may demonstrate correspondence between several types of physical interaction and the same conscious state, as the same tune may be played by a variety of different orchestral arrangements.
Frank Jackson (1982) and David Chalmers (1996) argued that scientific material external explanations cannot explain consciousness, since it is possible to conceive of a universe where the descriptions of material states of affairs that explain consciousness are true, but people do not develop consciousness, a world of zombies that act in response to stimuli without being conscious. For example, people may react to hunger by eating and to danger by defending themselves without being conscious of dining or fighting. Such a problem does not exist when scientists reduce water to two atoms of hydrogen and one atom of oxygen. Colin McGinn (1991) went further by suggesting that human beings are forever blocked from knowing the link between physical brain states and consciousness because introspective consciousness provides no immediate knowledge of brains, while neuroscientific knowledge of brains provides no access to consciousness.
Frank Jackson (1982) further attacked physicalism by demonstrating that some qualia, the subjective qualities of conscious experience, cannot be reduced to physical facts. Jackson introduced the following thought experiment: Suppose that a scientist named Mary was locked all her life in a room where everything was in black and white but had access to the world outside through black and white books and television. Mary could learn everything that science can teach us about colors, optics, and wavelengths, how they interact with the eye and transmitted to the brain, and so forth. Still, though Mary would be familiar with the physicalist-scientific explanation of color, it would not prepare her for anything like the actual experience of red, because it is irreducible to scientific physical descriptions.
Physicalist responses to Jackson's thought experiment claimed that Mary's new experience of red would not add to the number of facts she knows, rather it would represent knowledge of old facts in a new way, or a broadening of Mary's imagination. The description and explanation of mental causation of physical effects is a major problem for dualists like Jackson. Eliminativists do not think there is consciousness, only perceptions of it, no qualia, properties of experience, but perceptions of qualia "as if" there were mental objects. So, mental causation of physical events is not a problem for them because they deny the mental. Jackson advocated epiphenomenalism; he considers consciousness to be a side effect of physical processes that connects physical causes with effects. Consciousness is irrelevant for the generation of physical events. Consciousness emerges then from physical interactions, has properties that are irreducible to those of a physical lower level, and so is more than the sum of its parts. A related question is whether the emergence of consciousness may be explained by Darwinian evolution as conveying some sort of adaptationist advantage.
Self-conscious introspection was presented as a source for certain knowledge of history as well as the person. Philosophies of history presented themselves as that part of the historical process that is conscious of itself. As Nathan Rotenstreich has suggested, Giambattista Vico (1668–1744), Hegel, Marx, Benedetto Croce (1866–1952), and Robin George Collingwood (1889–1943) tried to base the very possibility of historical knowledge on the identity of subject and object. They constructed metaphysical entities like "ideal eternal history," "the spirit," "organic civilizations," "clashing civilizations," and so forth, to designate what they took to be the essence of history. If a philosophy of history is the self-consciousness of history, not just a consciousness of history, how history appeared to people who lived at a place and time, philosophers of history must occupy a privileged position within the historical process, at its end, the end of history. From the temporal vantage point of the end of a process, whether it is linear or cyclical, it is possible to discern its direction and meaning. Therefore philosophies of history from Vico to Francis Fukuyama, through Hegel, Marx, and Arnold Joseph Toynbee, have had to include apocalyptic themes in their philosophy to justify their claim to be conscious of the whole historical process. Still, mutually inconsistent philosophies of history seem to have been reflecting the consciousnesses of their particular eras rather than of the whole of history.
Self-Consciousness and Identity
Consciousness may refer to self-identity. As Locke put it in his Essay Concerning Human Understanding, "as far as … consciousness can be extended backwards to any past action or thought, so far reaches the identity of that person."
Hegel, Marx, György Lukács, Heidegger, and Jean-Paul Sartre (1905–1980) elaborated on the extent to which one's self-consciousness may not depend on introspection, but on how others conceive of oneself. Hegel introduced the master-slave dialectics, where the master's consciousness depends on the slave, since without the recognition of the slave, the master is not a master. Marx interpreted ideology as false consciousness, self-identity that does not conform to objective class interests, derived of relations to the means of production as owners or laborers. The Hungarian György Lukács (1885–1971) combined Hegel's phenomenology with Marx's materialism to present a theory of class-consciousness that became influential among European Marxists and emphasized reification and alienation. Heidegger analyzed alienation in modern mass societies where self-consciousness is imposed from without by the mass media and mass society, molding all people to become identical and anonymous. Sartre criticized the reduction of persons to roles, the promotion of essence above existence.
Under these influences, especially through the writings of Michel Foucault (1926–1984), historians have been tracing the history of such constructed and imposed self-consciousnesses, of sexual identities, madness, deviance and crime, ethnic and national identities, and so forth. These contributions to the history of consciousness have an emancipatory as well as a scholarly purpose, they intend to discover the history of self-consciousness as well as liberate groups from identities that were imposed on them from without to control and dominate.
Another debate within the writing of history and social sciences is about the primacy of consciousness and human intellect over being, material conditions and especially economic structures, in history. Materialists attempt to explain historical changes in consciousness including scientific theories and new religions and artistic styles, as resulting from economic changes, whereas idealists attempt to show the opposite. As the new president of free Czechoslovakia and a former political prisoner, playwright Václav Havel put it in his speech to the joint houses of Congress in February 1990: "The experience [of totalitarianism] has given me one great certainty: Consciousness precedes Being!"
See also Cartesianism ; Dualism ; Idealism ; Materialism in Eighteenth-Century European Thought ; Monism .
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