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Originally published as "Behaviorism," In Bringmann, W.G., Luck, H.E., Miller, R., & Early, C.E. (Eds.). A Pictorial History of Psychology. Chicago: Quintessence, 1997. Used with permission of the publishers. For more information, call 1-800-621-0387.
In 1913, at Columbia University, John Broadus Watson (1913) delivered a lecture entitled "Psychology as the Behaviorist Views It." To later generations of psychologists, reared in a discipline defining itself as the "science of behavior," this lecture would become known as the "behaviorist manifesto" and Watson would become known as the "father of behaviorism." There is, of course, some justification for this. In this lecture, Watson mounted a scathing attack on the mainstream definition of psychology as the science of mind or consciousness. Arguing in no uncertain terms that psychology should be viewed as "a purely objective experimental branch of natural science" whose theoretical goal is not the understanding of mind but the prediction and control of behavior, Watson blamed psychology's failure to "make its place in the world as an undisputed natural science" on the "esoteric" nature of its introspective method. Rejecting both introspection and the use of consciousness as an interpretive standard, he urged psychologists to adopt behavior as their unit of analysis.
In the years that followed, Watson used positions as Professor of Psychology at Hopkins, editor of the Journal of Experimental Psychology, and contributor to the popular press to proselytize for behaviorism. Even after his academic career came to an abrupt and involuntary end in 1920 (Watson, 1936), Watson continued to press his case; and by the time he made his final contribution to the debate in the early 1930s, methodological behaviorism and animal behavior research had become dominant features of the psychological landscape.
Like many origin myths, however, the story of Watson's founding of behaviorism is oversimplified and misleading. Watson was not the first to use objective, experimental methods in the study of behavior or to criticize psychology's use of the concept of "consciousness" or the method of introspection (Wozniak, 1993). Nor did psychologists flock suddenly to Watson's point of view (Samelson, 1981). It was more than ten years before behaviorism began to gain any real ground within American psychology, and when it did, it did so not by converting the old guard to Watson's vision but by attracting the young to a set of intellectual commitments that had already become broader, more varied, and philosophically more sophisticated than those of Watson.
The rise of behaviorism is often portrayed as a revolution in method, and in many ways it was. In 1913, psychology was the science of mind, the core phenomena of mind were those of consciousness, and the method of choice for the analysis of consciousness was introspection by a trained observer under controlled conditions. A scant 25 years later, mainstream psychology was the science not of mind but of behavior. The core phenomena of behavior were those of learning and memory, and the methods of choice for the analysis of leaning and memory involved purely objective observations of behavioral data varying as a function of the experimental manipulation of stimulus conditions (Woodworth, 1938).
There is little doubt that Watson's call for an objective science of behavior played an influential role in triggering the change that ensued; but the paper of 1913 was not itself the revolutionary moment that it is sometimes thought to be. By 1913, the study of human and animal behavior by means of purely objective methods under conditions of experimental manipulation and control of stimulus conditions had a forty year history. Indeed, Watson himself was a "behavior man" long before he was a "behaviorist," and his manifesto was prompted at least in part by the striking contrast that he perceived between the objective nature of available behavioral methods and the then prevalent ideology of an introspective psychology defined as the science of consciousness. Watson's primary goal at Columbia was to provide a rationale for the legitimation of behavior methods that had long been in use.
The first purely objective studies of behavior were probably those of Douglas Alexander Spalding and Charles Darwin. To distinguish instinctive from learned behavior, Spalding (1872, 1873) designed an extraordinary series of experiments in which he systematically manipulated an animal's experience (e.g., by placing hoods over the eyes of chicks still in the shell and only unhooding them several days after hatching) and carefully recorded relevant behaviors (e.g., the chick's first visually guided pecking movements), thereby providing a model for use of the experimental method in the study of behavior (see Gray, 1962, for an excellent discussion of Spalding's contributions).
Darwin's (1877) "Biographical Sketch of an Infant" exhibits the same attention to the detail of infant behavior that Spalding gave to that of young animals. As did Spalding, Darwin also went beyond simple observation to vary the conditions of stimulation and observe concomitant variation in behavior. To identify the effective stimulus for the infant's startle reaction, for example, Darwin compared the effect of shaking a paste-board box containing comfits near the child's face to those elicited by the same box when empty and by other noiseless objects shaken as near or much nearer the face.
Although objective in their observations and experimental in their variation of the conditions of behavior, neither Spalding nor Darwin was much inclined toward either the design of apparatus to control the scope of the animal's reaction or the quantification of response. One of the first to introduce apparatus and quantification into the study of animal behavior was Sir John Lubbock. In Ants, Bees, and Wasps. A Record of Observations on the Habits of the Social Hymenoptera, Lubbock (1882) provided precise, detailed, quantitative descriptions of the conditions of observation that were not much different from those to be found in the methods sections of modern journal articles. In addition, he reported actual data in the body of his text and used this data to compute simple summary statistics (e.g., pace of movement in ants learning to take an experimentally contrived route between food and nest).
These advances in methodology would alone have earned Lubbock a place in the history of objective research methods, but Lubbock employed two additional techniques of even greater importance for future research. Following his ants with a pencil as they pursued their way, Lubbock made detailed tracings of the ants' paths, possibly the first attempt to make an analog record of behavior for later coding. Second, and more importantly, to observe the progress made by his ants in learning to follow a new path from food to nest, Lubbock designed, built, and employed a number of simple pieces of apparatus that constrained the ants' movements. These pieces of apparatus were, in effect, the first animal mazes.
Between 1882 and 1894, the canons of adequate behavioral methodology continued to evolve. By the time James Mark Baldwin (1894) published his classic study of infant behavioral development, "The Origin of Right-Handedness," the use of apparatus for the measurement of behavior and registration of behavioral data was commonplace. Issues of experimental control, research design, and quantification had become paramount.
Baldwin's research consisted of a long series of controlled experiments carried out at home with his daughter. Placing different objects and cards of different colors in front of the child, he systematically varied distances and directions from her body and observed variations in her reaching. To guarantee accurate placement of the objects on each trial, Baldwin employed a set of specially designed measuring rods; and to minimize unwanted variability in the infant's behavior, he carried out his experiments under strictly controlled conditions, in the same location and at the same hour each day. To avoid biasing his daughter's hand preference, her position at the table was reversed midway through each series of experiments and, lest bias take place inadvertently, her parents even refrained from carrying her around in their arms until the experiments had been concluded. Finally, when Baldwin presented his data, he did so in quantitative, tabular form.
While Lubbock and Baldwin used laboratory-like procedures in the objective study of behavior, neither did so within the laboratory. Lubbock worked largely out of doors, making use of natural populations of insects; Baldwin worked with his daughter in the living room. The first psychologist to take intelligent animal behavior into the laboratory, to provide a clear quantitative account of the course of instrumental learning, and thereby to establish the study of animal learning as a laboratory science was Edward Lee Thorndike.
Thorndike's (1898) dissertation, Animal Intelligence, was one of the most influential publications of the first half century of psychological science. Besides offering a theory of instrumental learning later termed the "Law of Effect" and a conception of animal intelligence couched solely in terms of the organism's ability to form new connections, Thorndike developed ingenious apparatus for the observation of animal learning and employed it in systematic laboratory research. Bitterman (1969) has nicely described the appeal that Thorndike's general experimental technique had for generations of researchers:
It was objective: it minimized the influence of the observer...It was quantitative: the course of learning could be measured accurately in terms of the time taken for the appearance of the correct response on each trial. It was reproducible: the work of one investigator could be repeated and verified by others. It was flexible: the responses required could be varied in kind and complexity. It was natural:...not too remote from the animal's ordinary course of life...(and) it was convenient: a large enough sample of animals could be studied to provide a representative picture of each of a variety of species. (p. 446)
Supplemented by additional laboratory approaches to measuring way-finding, escape, and problem-solving (e.g., Kline, 1899; Small, 1900-1901; Hobhouse, 1901) and advances in stimulus control and quantification of response (e.g., Yerkes, 1907; Yerkes & Watson, 1911), objective methods developed rapidly after 1900. Issues of experimental control, quantification and registration of behavior, measurement, and research design were raised and addressed. By 1913, the tools for a psychology focused on what Watson would describe to Yerkes as "the scientific determination of modes of behavior...(using) an objective standard of interpretation...without mentioning consciousness or deviating from a (wide) biological point of view" were in place. The field of psychology, if not quite ready to embrace behaviorism, was at least ready to let Watson speak. And some sort of pronouncement was rather badly needed.
When Watson ascended the speaker's platform at Columbia, psychology was a discipline in serious disarray. The root source of the problem was an almost total lack of agreement among psychologists as to the nature of consciousness. William James (1904) had triggered the debate with his famous attack on the concept of consciousness, "Does Consciousness Exist?" Was consciousness a metaphysical entity or simply a particular sort of relationship toward objects into which portions of pure experience enter? Was consciousness a stream of experience, a kind of awareness, or thought? Was it an adaptive function or a composite of states; an energetic by-product of neurophysiological process, another name for associative learning, a form of arrested movement, a regulator of future adaptation, or simply another way of describing "self"? Truly, as Ralph Barton Perry (1904) put it, there was "no philosophical term at once so popular and so devoid of standard meaning" (p. 282).
In this state of affairs psychologists found themselves faced with a significant dilemma. On the one hand, even in the midst of conceptual chaos with respect to "consciousness," there was something on which almost all psychologists could agree: the right of psychology to exist as a science independent of biology and physiology was grounded in psychology's claim to being the science of consciousness. No matter how closely related psychology might become to its sister sciences, psychologists could always carve out their own academic and intellectual niche by emphasizing the study of consciousness as theirs and theirs alone.
On the other hand, psychologists realized that their claim to autonomy as a science was founded on quicksand. How could a science of consciousness function as an independent science in the face of almost total disagreement over the nature of its most basic subject matter? Psychology found itself in the unenviable position of being the science of "who knew what." The contradiction inherent in this state of affairs was all too painfully and embarrassingly evident. By itself this would have been bad enough, but matters were actually much worse.
In principle at least, psychologists might have been able to extract themselves from the horns of their dilemma by acting as scientists are supposed to act in the face of divergent opinion; they might have let the data decide. Unfortunately, however, disagreement over the nature of consciousness was not only disagreement over content, it was also conflict over method. To many it seemed that the only adequate method for the study of consciousness, whatever consciousness might be, was introspection. Yet introspection was the use of consciousness to study consciousness; problems of interpretation were multiplied geometrically. One could hardly expect reliability from a method erected on a foundation that shifted from experimenter to experimenter and theorist to theorist.
During the first decade of the new century, it would have been difficult to pick up a theoretical journal in psychology without being confronted with this controversy. In article after article, psychologists and philosophers of all persuasions attempted to address a series of critical questions: What is the nature of psychology as a science and how is it related to biology and physiology (Angell, 1907; Calkins, 1907; Cattell, 1906; Kirkpatrick, 1907)? What is consciousness, and how should the term "consciousness" be employed (Bode, 1908; Dewey, 1906; James, 1904; Judd, 1910; Perry, 1904)? By what criteria can consciousness be attributed to animals (Yerkes, 1905), and how is consciousness related to behavior on the one hand and nervous activity on the other (Bawden, 1910; Frost, 1912; Meyer, 1912; Yerkes, 1910)? What is the nature of introspection, what are its limits, and how are the data of introspection related to those provided by the observation of behavior (Pillsbury, 1904; Dodge, 1912; Dunlap, 1912)?
This was the context for Watson's lecture of 1913. Psychology was badly in need of someone who could cut a simple path through the chaotic web of controversy in which it found itself enmeshed. Watson did just that. None of his ideas were new. None of his ideas were complex. He simply pulled the strands of controversy together and severed them with a single, radical stroke. Watson threw out consciousness. By throwing out consciousness, he rid psychology of introspection. What remained--an objective psychology of behavior--he termed "behaviorism," described as a revolution, and claimed for his own.
Between 1913 and the emergence of neobehaviorism in the early 1930s (Hull, 1930, 1934, 1937; Skinner, 1931, 1932, 1938; Tolman, 1932), behaviorism moved from the margin to the mainstream of American scientific psychology. For the vast majority of American researchers, theoretical behaviorism had come to delimit psychology's questions and methodological behaviorism to define its practice as science. The growth of behaviorism reflected many factors. These included Watson's skill as a popularizer and publicist (Watson & McDougall, 1928; Watson, 1925, 1928), and the success of psychologists such as Floyd H. Allport (1919, 1924), Knight Dunlap (1926), Gilbert V. Hamilton (1925), Edwin B. Holt (1915a, 1915b), Karl S. Lashley (1923), George Herbert Mead (1922), Edward C. Tolman (1918, 1922), Robert S. Woodworth (1924), and Robert M. Yerkes (1917) in broadening the concept of behaviorism and extending behavioristic analysis to new psychological domains. In addition, philosophically oriented psychologists such as Albert P. Weiss (1919, 1925a, 1925b) and philosophers such as Edgar A. Singer (1924) provided a persuasive theoretical foundation for behaviorist method; and a number of widely used introductory texts written from a behavioristic point of view, most notably those of Watson (1919), Stevenson Smith and Edwin R. Guthrie (1921), and John Frederick Dashiell (1928), exerted a significant impact on students.
By the 1930s, behaviorism had become a complex affair. On the one hand, much of the program for which it stood was not exclusively its own. This was noted as early as 1924 by no less a figure than Woodworth (1924). Identifying a small set of intellectual commitments presumed by some to define behaviorism--objectivism, reliance on an animal behavior research program, neuromechanical reductionism, an emphasis on social process--Woodworth correctly pointed out that such commitments were common to psychologists of varying persuasions. Indeed, many who referred to themselves as functionalists, pragmatists, and objectivists would have and did find much in the behaviorist program with which they could still agree.
On the other hand, even among those who identified themselves as "behaviorists," agreement on the program was by no means unanimous. Early behaviorism took a variety of forms (Lashley, 1923; Woodworth, 1924). There was, of course, the radical behaviorism of Watson, a view notable for its extreme anti-mentalism, its radical reduction of thinking to implicit response, and, especially after 1916, its heavy and somewhat simplistic reliance on conditioned reactions (Watson, 1916, 1919; Watson & Raynor, 1920).
There was the relational behaviorism of the Harvard group, developed by Holt (1915a, 1915b; see also Wozniak, 1994b) under the influence of William James and transmitted, at least in part, to students such as Allport (1919) and Tolman (1918, 1922). Construing behavior as "a course of action which the living body executes or is prepared to execute with regard to some object or fact of its environment" (Holt, 1915a, p. 56), relational behaviorism was molar, purposive, and focused on the relationship between high-level behavioral mechanisms in the organism and the concrete realities of the social and physical environment. Closely related to this view was a kind of philosophical behaviorism, espoused primarily by philosophers and tied to pragmatism, in which "consciousness" was defined as a form of behavior guided by future results (Bawden, 1918; Bode, 1917, 1918).
At Ohio State, Weiss (1919, 1925a, 1925b) was developing a bio-social behaviorism based on a radical distinction between the level of theoretical discourse appropriate to behavior analyzed as social cause (i.e., "biosocially") and that appropriate to behavior analyzed as sensorimotor effect (i.e., "biophysically"). In Baltimore, Dunlap (1926, 1930), who had been both a Harvard graduate student with Holt and Watson's former departmental colleague at Johns Hopkins, was articulating a reaction psychology that blended attacks on introspection, instinct, and images, with an "insistence on response or reaction as the basis of mental processes, including thought processes [and consciousness]" (Dunlap, 1930, p. 59).
At Minnesota, Lashley (1923) was arguing a physiological behaviorism in which physiological analysis of behavior could be considered to provide a complete and adequate account of all conscious phenomena. At Chicago, Mead (1922) was elaborating a social behaviorism of mind, meaning, self, language, and thinking that emphasized the social character of behavior and the behavioral character of mind. Finally, in a number of institutions, a sort of eclectic behaviorism was emerging--a behaviorism that assimilated whatever seemed strongest and most reliable in the views of others. This was the sort of behaviorism to be found in texts such as Dashiell's (1928) Fundamentals of Objective Psychology.
As it existed during this period, behaviorism clearly resisted simple definition. It was complex, varied, and changing. There was, however, a common core within this variability--psychology was defined as the natural science of behavior; method and theory were objectivist; behavior, animal or human, was conceived as a pattern of adjustment (innate and acquired, skeletal and visceral, explicit and implicit) functionally dependent upon stimulus conditions in the environment and factors of habit and drive in the organism; and animal behavior, ontogenesis, drive reduction, habit formation, social behavior, and language were emphasized in theory and research (cf., Wozniak, 1994a, for a more in-depth discussion). It was this core that captured the imagination of young psychologists, spread behaviorism within American psychology, and prepared the way for the theoretically more sophisticated neobehaviorisms of the 1930s.
1 Another exceptionally important individual in this regard was Francis Galton (see especially Galton, 1883). It will come as no surprise to anyone familiar with the work of Francis Galton that some of Lubbock's apparatus development took place in collaboration with Galton. See, for example, Lubbock (1882), p. 263.
2 Letter from Watson to Yerkes, October 29, 1909, quoted in Buckley (1989), p. 71.
3 Terms adopted here to distinguish among the varieties of early behaviorism are, for the most part, those of the author. Although detailed discussion of the variability existing within behaviorism in the 1920's is beyond the scope of this article, it is worth pointing out that disagreements typically revolved around four issues: a) the possibility of achieving a complete explanation of behavior in terms of the principles of nervous function (the neuromechanical program); b) rejection of any special role for the central nervous system in the organization of behavior (peripheralism); c) the relation of acquired to hereditary mechanisms (the nature of instinct); and d) the role of mental facts and mental terms, if any, in behavioral theory.
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