behaviorism broadly, the view that behavior is fundamental in understanding mental phenomena. The term applies both to a scientific research program in psychology and to a philosophical doctrine. Accordingly, we distinguish between scientific (psychological, methodological) behaviorism and philosophical (logical, analytical) behaviorism.
Scientific behaviorism. First propounded by the American psychologist J. B. Watson (who introduced the term in 1913) and further developed especially by C. L. Hull, E. C. Tolman, and B. F. Skinner, it departed from the introspectionist tradition by redefining the proper task of psychology as the explanation and prediction of behavior – where to explain behavior is to provide a ‘functional analysis’ of it, i.e., to specify the independent variables (stimuli) of which the behavior (response) is lawfully a function. It insisted that all variables – including behavior as the dependent variable – must be specifiable by the experimental procedures of the natural sciences: merely introspectible, internal states of consciousness are thus excluded from the proper domain of psychology. Although some behaviorists were prepared to admit internal neurophysiological conditions among the variables (‘intervening variables’), others of more radical bent (e.g. Skinner) insisted on environmental variables alone, arguing that any relevant variations in the hypothetical inner states would themselves in general be a function of variations in (past and present) environmental conditions (as, e.g., thirst is a function of water deprivation). Although some basic responses are inherited reflexes, most are learned and integrated into complex patterns by a process of conditioning. In classical (respondent) conditioning, a response already under the control of a given stimulus will be elicited by new stimuli if these are repeatedly paired with the old stimulus: this is how we learn to respond to new situations. In operant conditioning, a response that has repeatedly been followed by a reinforcing stimulus (reward) will occur with greater frequency and will thus be ‘selected’ over other possible responses: this is how we learn new responses. Conditioned responses can also be unlearned or ‘extinguished’ by prolonged dissociation from the old eliciting stimuli or by repeated withholding of the reinforcing stimuli. To show how all human behavior, including ‘cognitive’ or intelligent behavior, can be ‘shaped’ by such processes of selective reinforcement and extinction of responses was the ultimate objective of scientific behaviorism. Grave difficulties in the way of the realization of this objective led to increasingly radical liberalization of the distinctive features of behaviorist methodology and eventually to its displacement by more cognitively oriented approaches (e.g. those inspired by information theory and by Chomsky’s work in linguistics). Philosophical behaviorism. A semantic thesis about the meaning of mentalistic expressions, it received its most sanguine formulation by the logical positivists (particularly Carnap, Hempel, and Ayer), who asserted that statements containing mentalistic expressions have the same meaning as, and are thus translatable into, some set of publicly verifiable (confirmable, testable) statements describing behavioral and bodily processes and dispositions (including verbalbehavioral dispositions). Because of the reductivist concerns expressed by the logical positivist thesis of physicalism and the unity of science, logical behaviorism (as some positivists preferred to call it) was a corollary of the thesis that psychology is ultimately (via a behavioristic analysis) reducible to physics, and that all of its statements, like those of physics, are expressible in a strictly extensional language. Another influential formulation of philosophical behaviorism is due to Ryle (The Concept of Mind, 1949), whose classic critique of Cartesian dualism rests on the view that mental predicates are often used to ascribe dispositions to behave in characteristic ways: but such ascriptions, for Ryle, have the form of conditional, lawlike statements whose function is not to report the occurrence of inner states, physical or non-physical, of which behavior is the causal manifestation, but to license inferences about how the agent would behave if certain conditions obtained. To suppose that all declarative uses of mental language have a fact-stating or -reporting role at all is, for Ryle, to make a series of ‘category mistakes’ – of which both Descartes and the logical positivists were equally guilty. Unlike the behaviorism of the positivists, Ryle’s behaviorism required no physicalistic reduction of mental language, and relied instead on ordinary language descriptions of human behavior. A further version of philosophical behaviorism can be traced to Wittgenstein (Philosophical Investigations, 1953), who argues that the epistemic criteria for the applicability of mentalistic terms cannot be private, introspectively accessible inner states but must instead be intersubjectively observable behavior. Unlike the previously mentioned versions of philosophical behaviorism, Wittgenstein’s behaviorism seems to be consistent with metaphysical mind–body dualism, and is thus also non-reductivist.
Philosophical behaviorism underwent severe criticism in the 1950s and 1960s, especially by Chisholm, Charles Taylor, Putnam, and Fodor. Nonetheless it still lives on in more or less attenuated forms in the work of such diverse philosophers as Quine, Dennett, Armstrong, David Lewis, U. T. Place, and Dummett. Though current ‘functionalism’ is often referred to as the natural heir to behaviorism, functionalism (especially of the Armstrong-Lewis variety) crucially differs from behaviorism in insisting that mental predicates, while definable in terms of behavior and behavioral dispositions, nonetheless designate inner causal states – states that are apt to cause certain characteristic behaviors.
See also COGNITIVE SCIENCE, FUNCTIONAL — ISM , PHILOSOPHY OF MIND , PHILOSOPHY OF PSYCHOLOGY , RYLE , VERIFICATIONIS. A.M.