Behaviourism: The Early Years[1]

Robert H. Wozniak[2]
Bryn Mawr College

In 1913, in one of the most famous lectures[3] in the history of psychology, John Broadus Watson (1878-1958)[4], a 35-year-old "animal behavior man" from Johns Hopkins University, called for a radical revisioning of the scope and method of psychological research.:

"Psychology as the behaviorist views it is a purely objective experimental branch of natural science. Its theoretical goal is the prediction and control of behavior. Introspection forms no essential part of its methods, nor is the scientific value of its data dependent upon the readiness with which they lend themselves to interpretation in terms of consciousness. The behaviorist, in his efforts to get a unitary scheme of animal response, recognizes no dividing line between man and brute. The behavior of man, with all of its refinement and complexity, forms only a part of the behaviorist's total scheme of investigation."[5]

Introspection was to be abandoned in favor of the study of behavior. Behavior was to be evaluated in its own right, independent of its relationship to any consciousness that might exist. The concept of "consciousness" was to be rejected as an interpretive standard and eschewed as an explanatory device. As an objective, natural science, psychology was to make no sharp distinction between human and animal behavior; and its goal was to develop principles by which behavior could be predicted and controlled.
Published in the Psychological Review shortly after its delivery and incorporated within the first chapter of Watson's 1914 Behavior: A Textbook of Comparative Psychology[6], this lecture eventually came to be known as the "behaviorist manifesto." Generations of psychologists, reared in a post-Watsonian discipline that defined itself as the "science of behavior," were taught that Watson was the father of behaviorism and that February 24, 1913 was the day on which modern behaviorism was born.[7]
There is, of course, some truth to this. On that fateful day in 1913, Watson did reject the mainstream view, and he did do so in uncompromising terms. An indefatigable and effective self-publicist fond of referring to himself in the third person as "the behaviorist," Watson then embarked on a personal campaign to change the face of psychological science. Using his public position as a professor of psychology at Hopkins, editor of several of the field's most influential journals[8],and contributor to the popular press, he labored ceaselessly on behalf of his behavioristic vision[9]. Even when his career as an academic psychologist was abruptly and involuntarily cut short in 1920[10], Watson continued to press his case. By the time he left the field for good in the early 1930s, behaviorism had succeeded in taking center stage within American psychology.
Like many origin myths, however, the story of Watson's founding of behaviorism is oversimplified and misleading. Watson was by no means the first to criticize psychology's use of the concept of "consciousness" or the method of introspection; his was not even the first attempt to rid psychology of "consciousness" altogether or to argue the case against all use of introspection[11]. Watson was not the first to use objective, experimental methods in the study of behavior[12], or to propose a unitary scheme for the investigation of animal and human response.[13] Indeed, even prediction and control of behavior had been articulated as worthy goals of psychological science prior to Watson's manifesto of 1913.[14]
What happened in 1913, then, was not novel; it was not a sharp break with the past. Nor did it create an immediate revolution. As Samelson has described it:[15]

"Supported by the Zeitgeist, Behaviorism supposedly spread quickly through psychology after the publication of Watson's manifesto in 1913. But an extensive search of published and unpublished source material from 1913 to 1920 shows only limited support and a good deal of resistance; documentary evidence for the conversion of psychologists to radical behaviorism during these years is hard to find. Though faced with some troubling problems, the discipline was not eager to renounce its established scientific authority and expertise on the mind."[16]

Yet behaviorism did eventually spread throughout American psychology. During the 1920s, across the work of a growing number of psychologists, there emerged a reasonably coherent set of intellectual commitments to which the name "behaviorism" gradually became attached. Based on the rejection of mentalism in psychological theory, a dedication to the use of objective methodology in research, and a strong concern with practical application of psychological knowledge to the prediction and control of behavior, "behaviorism" in the 1920s owed an obvious debt to Watson.
At the same time, however, behaviorism grew during this period in part by diverging from and transcending Watson. Influenced by broader conceptions of objectivism and of psychological process developing at Harvard, Columbia, Chicago, Missouri, Ohio State, Minnesota, North Carolina, and even Hopkins, behaviorism had become, by the end of the 1920s, a more thoroughly elaborated, theoretically more varied and sophisticated approach than anything to be found in Watson's own writings.[17] It was this richer version of behaviorism, rather than Watsonianism per se, that succeeded in transforming American psychology; and it did so not by converting the old guard but by capturing the enthusiasm of the young. As succeeding generations of psychologists entered the discipline, objectivism gradually became the norm; and by the mid-1930s, American psychology had become the science of behavior, and behaviorism, methodological and/or theoretical, had become its dominant orientation.
Early behaviorism, then, was a complex affair. On the one hand, much of the program for which its stood was not exclusively its own. This was noted as early as 1924 by no less a figure than Robert Sessions Woodworth (1869-1962).[18] 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[19]. 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 theoretical reliance on conditioned reactions.[20] There was the relational behaviorism of the Harvard group, developed by Edwin Bissell Holt (1873-1946)[21] under the influence of William James (1842-1910) and transmitted, at least in part, to students such as Floyd Henry Allport (1890-1978) [22], and Edward Chace Tolman (1886-1959)[23]. Conceiving of 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,"[24] Holt's 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.[25]
At Ohio State, under the influence of his mentor, Max Frederick Meyer (1873-1967), Albert Paul Weiss (1879-1931) 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").[26] In Baltimore, Knight Dunlap (1875-1949)[27], 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]."[28]
At Minnesota, Karl Spencer Lashley (1890-1958) was arguing a physiological behaviorism in which the physiological analysis of behavior could be considered "a complete and adequate account of all the phenomena of consciousness."[29] At the University of Chicago, George Herbert Mead (1863-1931), who had been on the faculty since Watson was a graduate student, 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[30]. 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 a text such as Dashiell's Fundamentals of Objective Psychology.[31]
Early Behaviorism as an Orientation to Psychology
As it existed during this period, behaviorism clearly resisted simple definition. Early behaviorism was not simple. It was complex, varied, and changing. Yet there was a common core within this variability-a definite movement away from certain ideas and practices and toward others. If early behaviorism could not be simply defined, it could nonetheless be broadly characterized in terms of a constellation of features including intellectual commitments concerning the nature of psychology as science and the fundamental nature of behavior and a set of theoretical and research emphases that followed directly from such commitments. It is this constellation of commitments and emphases, taken together, that gave early behaviorism its distinctive orientation. As context for the foundational monographs and papers reprinted in this series, the remainder of this introduction will be devoted to an analysis of this orientation.
Level 1 Commitments-The Nature of Psychology as Science.
Psychology as a natural science. More than anything else, early behaviorism was committed to the assumption that physical processes and only physical processes play a causal role in the determination of psychological phenomena. The procedures of scientific psychology are the procedures of any science. As Dashiell put it: "A scientific study of man assumes that he is a complex physical object moving in a world of physical energies and relationships. Anything of psychological interest about man is to be treated as a physical phenomenon...as a natural occurrence in which material bodies effect energy changes...the events with which we are concerned are continuous with, and similar to, all other events in the world of nature." [32]
Whether or not "consciousness" had any role to play in psychology as a natural science depended, for a given theorist, on how consciousness was construed. If consciousness was either reconceptualized in terms of physical processes or construed as an epiphenomenal (albeit psychical) byproduct of physical process, it was typically included within psychology as a datum although never as an explanation. While behaviorists in this period were of several minds on how to treat consciousness, they were absolutely united in rejecting any notion of non-material, psychical determinism of the sort implied in the traditional concept of "consciousness." Weiss was especially forceful in making this point. Behaviorism, he asserted, is "a protest against all attempts to explain human achievement by the introduction of an element which is beyond the range of physical measurement. [...] On this basis human behavior, human conduct, human achievement, human personality, are regarded as belonging to the same phenomenological categories as those which now form the subject of physics, chemistry, biology, in their strictly mechanical interpretations..." [33]
As a natural science, psychology takes the study of behavior as its fundamental task. Whatever else psychology might be, for early behaviorism it was fundamentally the science of behavior, where behavior was defined in terms of the organism's organized response to stimulation. Depending on the theorist and the reaction system in question, response might be overt or covert, implicit or explicit, clear and well-defined or vague and obscure, molecular or molar, simple or complex. Response might consist of an actual act or simply of the adoption of an attitude, tendency, or set; it might be controlled by the proximal stimulus or directed toward objects in the environment. But however otherwise conceived, for the behaviorist, response involved the operation of effector systems-muscles and glands. Behavior, as Dashiell indicated, had to do with "how, when, and why a man does this or that, acts thus and so, desires, seeks, accepts, rejects-in a word, moves."[34]
As a natural science, psychology is committed to methodological objectivism. As scientists, behaviorists focused on objective, behavioral methods. Although they were by no means the first to emphasize objective methodology in the study of psychological function,[35] objective methods were the cornerstone on which they hoped to build their scientific edifice. In this spirit, Watson devoted an entire chapter in Psychology from the Standpoint of a Behaviorist to "objective methods as employed in human psychology"[36] and Dashiell informed his students that: "The methods of psychological investigation differ no whit in their essential character from the various methods employed in other natural sciences."[37]
As a natural science, psychology is committed to increasing scientific understanding of behavior for the purpose of prediction and control. For early behaviorism, the science of behavior was to lay the groundwork for a behavior technology. Just as behaviorists were not the first objectivists, neither were they the first psychologists to emphasize the application of psychological insight in practical human affairs. From the outset, however, behaviorism defined the goal of scientific psychology in terms (prediction and control) that led naturally to questions concerning the relevance of behavior mechanisms (e.g., habit formation) to everyday life.[38] As Watson described it in 1919, "...the goal of psychological study is the ascertaining of such data and laws that, given the stimulus, psychology can predict what the responses will be; or, on the other hand, given the response, it can specify the nature of the effective stimulus."[39] The early behaviorists were convinced that with such information in hand, "the twentieth century...[would] become remarkable for the development of psycho-technology."[40]
Level 2 Commitments-The Fundamental Nature of Behavior as Subject Matter for Scientific Psychology
Adjustment and maladjustment. In the 1920s, behaviorists were united in the assumption that behavior results when the organism's relationship to the environment must be changed if it is to survive and prosper. Behaviorism referred to such states as "maladjustments" and conceived of the occurrence of maladjustment as the "sine qua non" for behavior.[41] Maladjustment is a natural byproduct of change in the organism (e.g., an increase in drive level) or in the environment (e.g., a rise in ambient air temperature); and behavior, which is a process of adjustment, consists of responses on the part of the organism that tend to restore balance in its relationship to the environment.
Phylogenetic continuity. For early behaviorism, animal and human behavior exist in an "unbroken continuity,"[42] Animals and humans share both mechanisms and fundamental forms of overt adjustment to the environment. This view, which originated with Watson's desire to place the study of animal behavior high on the psychological research agenda,[43] was reinforced by psychology's early success in extending trial-and-error and conditioning analyses from animals to humans. As Dashiell summarized the continuity commitment: "The genus and species Homo sapiens is moved by the same forces without and within as are the lower animal forms, and expresses them in the same general types of actions and action-tendencies. The differences are differences in degree..."[44]
The Determination of Behavior. Behavior, from a behaviorist point of view, is a joint function of stimulating conditions in the environment and characteristics (drive states, hereditary reflexes, acquired systems of habit, emotions, mechanisms of implicit stimulation) within the organism. In its earliest formulations, this commitment, from which behaviorism later became known as "stimulus-response" or "S-R" psychology, was somewhat too simply phrased. Thus, for example, in 1919, Watson said only that: "In each adjustment there is always both a response or-act and a stimulus or situation which call [sic] out that response....the stimulus is always provided by the environment, external to the body, or by the movements of man's own muscles and the secretions of his glands...[and] responses always follow relatively immediately upon the presentation or incidence of the stimulus."[45]
Throughout the 1920's, however, as the importance of drive states, the complexity of habit systems, and the implications of the concept of response-produced stimulation-the notion that every response of the organism, even those that are covert, is also a stimulus to further response-were more fully worked out, the S-R formulation became more sophisticated. In 1928, Dashiell characterized the state of the art in the following fashion: "...not all of a man's activity is directly excited from without...His conduct is just as much the expression of his own internal energies with all their traces of previous environmental influences and of his modes of response thereto [...] One thing should be clear...the conception of a simple stimulus leading to a simple response is only a convenient abstraction from the actual facts. [...] S X O->R (in which O represents these organic factors) would be a more adequate formula."[46] he Classification of Behavior. Although many behaviorists pointed to the indissociability of response types in actual behavior, early behaviorism remained wedded to the classification of response in terms of three major categories: a) somatic/hereditary (pre-potent reflexes, instinctive reaction tendencies); b) somatic/acquired (systems of habits); or c) visceral/hereditary and acquired (emotions). Responses in all three categories were then further classified as explicit, implicit, or preparatory (attitudinal).
Distinctions between instinctive, habitual, and emotional reaction systems were delineated by Watson in 1919.[47] "Human action as a whole," he wrote. "can be divided into hereditary...(emotional and instinctive), and acquired modes of response (habit)."[48] For Watson, all three response modes were "pattern reactions," complex systems of reflexes that function in an organized fashion when the organism is confronted with an appropriate stimulus.
Although behaviorists recognized that emotional reactions might involve somatic elements (e.g., facial expressions), they conceived of emotion primarily as "visceral and glandular."[49] Instincts and habits, on the other hand, were thought to be "movements principally of the striped muscles,"[50] differing from one another only in that instincts were inherited, habits acquired. In animals low in the evolutionary hierarchy, hereditary mechanisms were believed to predominate. With ascent of the phylogenetic scale, acquired response was thought to become increasingly important. In human beings, virtually all complex behavior was presumed to be acquired. Human behavioral ontogenesis, therefore, was conceived as consisting largely if not entirely in the elaboration of organized habit systems on a foundation provided by the instinctive and emotional reaction systems of the newborn.
In addition to being classified as instinctive, habitual, or emotional, responses were also categorized in terms of the extent to which they were overt and accessible to observation. Responses that were external and publicly observable were termed "explicit;" responses that were internal and covert were "implicit." Among implicit responses there were those that were fully executed, those that were so abbreviated as to be merely incipient or nascent movements, and those that did not involve execution at all but merely prepared (oriented) the organism to respond with a particular pattern of behavior when stimulation was adequate to release the response. Following Holt, Allport typically referred to such orienting responses as "attitudes."[51] Dashiell preferred the term "response set."[52]
Behavioral Redefinition of the Traditional Categories of Mentalism. At the heart of early behaviorism lay a commitment to the notion that mentalistic categories and concepts (e.g., perception, attention, meaning, symbol, memory, purpose, abstraction, generalization, thought) must either be redefined in terms of behavioral mechanisms or discarded altogether. In 1913, Watson excluded mind in its entirety from behaviorism. Not only was consciousness rejected as both fact and concept, but associated mental terms were to be discarded as well. This was the most extreme version of this commitment; and other early behaviorists did not, as a rule, follow Watson down this path. By far the most common approach was to redefine the standard concepts of mental analysis in strictly behavioral terms. A few examples will suffice.
"Perceiving," for Dashiell, was an "anticipatory set (largely implicit) that orients...[the organism] for a certain line of conduct with reference to...[the] situation."[53] "Meaning" was "the pattern of reaction-tendencies awakened by...[the thing perceived.]"[54] For Allport, a "symbol" was "a brief and labile response usually undetected in outward behavior, but capable of being substituted for overt responses."[55] "Consciousness," in Weiss's terms, was "only the functioning of obscure contractile elements, which in turn stimulate adjacent receptors that release the verbal overt response..."[56] And "thinking," in that famous analysis of Watson, simply meant "subvocal talking, general body language habits, bodily sets or attitudes which are not easily observable without instrumentation or experimental aid."[57]
Areas of Emphasis
In addition to fundamental commitments concerning psychology as the natural science of behavior, early behaviorism was also characterized by a set of distinctive emphases that followed, almost as corollaries, from its intellectual commitments. Taken singly and with regard to their content, these emphases were not unique to behaviorism.[58] As a group, however, and evaluated in terms of relative strength, they combined to give the behaviorism of the 1920's its particular look.[59]
Animal Models. Behaviorism emphasized the identification of fundamental mechanisms in animal behavior (e.g., trial and error learning, conditioning) and use of such mechanisms, without significant theoretical revision, in the explanation of human behavior. This approach, which followed directly from the commitment to phylogenetic continuity, was largely unquestioned among early behaviorists. Indeed, as behavioral research began to develop in the late 1920's and 1930's, many of the most important studies focused on animals and many core theoretical concepts came to be defined almost entirely in terms of the procedures of animal behavior research.
Ontogenesis. The study of development loomed large in the early behaviorist research program. This followed from the assumption that habits are elaborated out of innate response systems (instinct, emotions) present in the newborn infant and develop over the life course. As Dashiell put it, "life-activities...vary by all degrees between the two poles of unorganized, scattered, excess activity, and the smooth-running performance of routine motions...[I]n the development of the individual human from birth to maturity, the central part of the story is the organization of definite routine actions drawn from the reservoir of the random, excess activities."[60]
Development is a theme to which Watson returned again and again. Thus, for example, in discussing research on instinct and habit, he informed his readers that "...to study the details of hereditary response...we have to adopt a genetic method. We have to start with the baby's advent...and follow his development step by step, noting the first appearance of the hereditary forms of reaction, their course and effect upon the moulding of the child's whole personality; and the early beginnings of acquired modes of response."[61] This was also a theme to be found in Dashiell,[62] Weiss,[63] Allport,[64] Hamilton,[65] and most early behaviorist texts.
Drive Reduction. Following their commitment to the principle that behavior, as a process of adjustment, results from a state of maladjustment between the organism and its environment, early behaviorists emphasized internal drive states (sex, hunger, thirst, etc.) and drive reduction theories of motivation. One result of this orientation was an inclination to view the organism as passive. All other things being equal, the organism was assumed to tend toward a state of quiescence or non-response. As Dashiell phrased it: "No expression without impression; no response without stimulation. A man does nothing, is not active, in any manner involving the effectors...unless in some way he is being influenced by energy-changes occurring inside or outside of him which play upon his receptors..."[66]
Habit formation. An emphasis on habit formation defined in terms of mechanisms of trial-and-error elaboration of response and conditioned stimulus substitution was probably the characteristic with which early behaviorism was most closely associated. Behaviorism in the 1920's was first, last, and always a psychology of habit formation. Acquired behavior, no matter how complex-thinking, talking, even scientific activity itself-could, in the final analysis, be reduced to habit.
The trial-and-error mechanism (increase in random movement upon confrontation with a problem situation, accidental success when chance response alters the organism or the environment in the direction of greater adjustment, and gradual, mechanical selection and reinforcement of successful movement) was usually employed to explain efferent modification, the elaboration of the response itself. The conditioned reaction was typically evoked to explain afferent modification-change in the effectiveness of stimuli, including those that are purely social and symbolic, in eliciting a given response.
Dashiell made it quite clear just why conditioning as a mechanism of habit formation exerted such an appeal to behaviorists. Conditioning, he pointed out, "yields...an account of learning (a) that is highly definite, and (b) that is cast in wholly objective terms, in terms of biological processes demonstrable in subhuman as well as human forms without any recourse to or dependence upon reports of the matter by the subjects concerned."[67] Allport was just as enthusiastic: "No single law of human or animal behavior is of more far-reaching significance than that of the conditioned reflex. Half of the process of education consists of transferring appropriate responses to new and more finely discriminated stimuli."[68]
Social Behavior. An emphasis on social behavior followed directly from one of early behaviorism's most versatile assumptions-the notion that responses have stimulus value. Whenever the organism behaves, its responses are also stimuli-for itself and for others. "This principle," as Watson correctly recognized, "...is one of the most important in the whole of psychology. By means of impulses from the muscles themselves man becomes partially independent of the impulses from the so-called higher senses...We see the final perfection of the process in thought where we have a substituted word process for practically every object in our environment. These substituted word processes can initiate general bodily movements exactly as do the visual or auditory stimuli for which they stand."[69]
Substituted word processes and other response-produced stimulation can also affect the behavior of other organisms. As Allport put it, a "social stimulus" is "any reaction, made by an animal (human or infra-human)...which produces a response in another."[70] Social stimuli, he continued, "involve behavior in two ways. (1) They are in themselves usually responses to stimuli either social or non-social in character. (2) They produce responses in others."[71] Social behavior, in other words, is a process that combines reciprocal and self stimulation. Dashiell described social behavior in the following fashion:

"Just as a person is stimulated by and reacts upon such objects as a chair, a stone, a bit of food, likewise he is stimulated by and he reacts upon those more mobile objects we call his fellows. The principal difference in the two cases is that environmental objects of the social type are themselves animate and behaving organisms that are stimulable and are reactive; and so the interrelations of a given person with them are capable of very high elaboration and refinement.
"Finally, a striking feature of human behavior, especially, is the manner in which the reactions serving to stimulate social objects come also to stimulate the original actor himself; and there are built up whole trains of behavior consisting principally of self-stimulation and response"[72]

Language. For behaviorists in the 1920's, self-stimulation and response was intimately linked to language. For both the self in thinking and the social listener in communication, language responses were conceived as substitute, symbolic stimuli, independent of the sensory attributes of the original stimulus. In this role, they subserved the related functions of abstraction and generalization. As Weiss , who pioneered this analysis, asserted: "...many different receptor patterns representative of many different sensory situations and relations, are connected to the same language response and through this common path the individual may react in a specific manner to all the objects, situations, and relations thus concerned, even though there is very little sensory similarity between them."[73]
Conclusion
Psychology defined as the natural science of behavior, wedded to objectivism in method and theory and to a goal of behavioral prediction and control; behavior, animal or human, 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; emphasis in research and theory on animal behavior, ontogenesis, drive reduction, habit formation, social behavior, and language-this was the orientation that began, following World War I, to capture the imagination of young psychologists and to spread within American psychology throughout the 1920's. This was behaviorism in its early form.

---

Footnotes 1. To be published in: Wozniak, R.H. (Ed). (1994). Reflex, Habit and Implicit Response: The Early Elaboration of Theoretical and Methodological Behaviourism 1915-1928. London: Routledge/Thoemmes [Volume 1 in Behaviourism: The Early Years, a series edited by Robert H. Wozniak]. 
2. The author would like to express his gratitude to Jana M. Iverson for her critical reading of this and other introductions written for this series. 
3. Watson, J.B. (1913). Psychology as the behaviorist views it. Psychological Review, 20, pp. 158-177.
4. For biographical material on Watson, see: Buckley, K.W. (1989). Mechanical Man: John Broadus Watson and the Beginnings of Behaviorism. New York: Guilford Press. 
5. Watson (1913), p. 158. 
6. Watson, J.B. (1914). Behavior: A Textbook of Comparative Psychology. New York: Henry Holt & Co. 
7. Herrnstein, R.J. & Boring, E.G. (1966). A Sourcebook in the History of Psychology. Cambridge, MA: Harvard University Press. See especially p. 507. 
8. At various times, Watson edited the Psychological Review, Psychological Bulletin, Psychological Monographs, Behavior Monographs, and the Journal of Experimental Psychology.
9. See Watson, J.B. (1924/1925). Behaviorism. New York: People's Institute Publishing Company; and Watson, J.B. & McDougall, W. (1928). The Battle of Behaviorism. London: Kegan Paul, Trench, Trubner & Co. [portions of both are reprinted in this volume]. 
10. Watson, J.B. (1936). John Broadus Watson. In C. Murchison (Ed). A History of Psychology in Autobiography. Worcester, MA: Clark University Press, pp. 271-281. 
11. See Wozniak, R.H. (Ed.) (1993a). Theoretical Roots of Early Behaviourism: Functionalism, the Critique of Introspection, and the Nature and Evolution of Consciousness. London: Routledge/Thoemmes. 
12. See Wozniak, R.H. (Ed.) (1993b). Experimental and Comparative Roots of Early Behaviourism: Studies of Animal and Infant Behaviour. London: Routledge/Thoemmes. 
13. See Wozniak, R.H. (1993c). Conwy Lloyd Morgan, mental evolution, and The Introduction to Comparative Psychology. In C.L. Morgan. The Introduction to Comparative Psychology. London: Routledge/Thoemmes, pp. vii-xix. 
14. See Wozniak, R.H. (1993d). Jacques Loeb, Comparative Physiology of the Brain and Comparative Psychology. In J. Loeb. Comparative Physiology of the Brain and Comparative Psychology. London: Routledge/Thoemmes, pp. vii-xxiii.
15. Samelson, F. (1981). Struggle for scientific authority: The reception of Watson's behaviorism, 1913-1920. Journal of the History of the Behavioral Sciences, 17, 399-425. This carefully researched and beautifully documented article is the definitive source of information on the early reception of Watson's behaviorism.
16. Ibid., p. 399. For contemporary reactions to Watson's early formulations, see Thorndike, E.L. & Herrick, C.J. (1915). Watson's 'Behavior.' Journal of Animal Behavior, 5, pp. 462-470; and Yerkes, R.M. (1917). Behaviorism and genetic psychology. Journal of Philosophy, Psychology, and Scientific Methods, 14, pp. 154-160 [both reprinted in this volume]. 
17. To give Watson his due, it is important to remember that his later writings were produced for a popular audience. 
18. Woodworth, R.S. (1924). Four varieties of behaviorism. Psychological Review, 31, pp. 257-264 [reprinted in this volume]. 
19. A number of commentators make this point. See, for example, Lashley, K.S. (1923). The behavioristic interpretation of consciousness. Psychological Review, 30, pp. 237-272, 329-353; and Woodworth (1924). 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 introduction, 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. 
20. See Watson, J.B. (1916). The place of the conditioned-reflex in psychology. Psychological Review, 23, pp. 89-116; Watson, J.B. & Raynor, R. (1920). Conditioned emotional reactions. Journal of Experimental Psychology, 3 pp. 1-14; Watson, J.B. (1924). What is behaviorism? The old and new psychology contrasted. In J.B. Watson (1924/1925), pp. 3-41; and Watson, J.B. (1928). Behaviorism-the modern note in psychology. In J.B. Watson & W. McDougall (1928), pp. 7-41 [all reprinted in this volume]; See also Wozniak, R.H. (1994a). John B. Watson and Psychology from the Standpoint of a Behaviorist. In J.B. Watson. Psychology from the Standpoint of a Behaviorist. London: Routledge/Thoemmes.
21. Holt's classic statement of his relational position appears in Holt, E.B. (1915). Response and cognition. Journal of Philosophy, Psychology, and Scientific Methods, 12, pp. 365-373, 393-409 [reprinted in this volume]; See also the discussion of Holt's ideas in Wozniak, R.H. (1994b). Floyd Henry Allport and the Social Psychology. In F.H. Allport. Social Psychology. London: Routledge/Thoemmes. 
22. See Allport, F.H. (1919). Behavior and experiment in social psychology. Journal of Abnormal Psychology, 14, pp. 297-306 [reprinted in this volume]; See also Wozniak, R.H. (1994b)
23. See Tolman, E.C. (1918). Nerve process and cognition. Psychological Review, 25, pp. 423-442; and Tolman, E.C. (1922). A new formula for behaviorism. Psychological Review, 29, pp. 44-53 [both reprinted in this volume].
24. Holt, E.B. The Freudian Wish and Its Place in Ethics. New York: Henry Holt and Company, p. 56. 
25. See, for example, Bode, B.H. (1917). The nature of the psychical. Journal of Philosophy, Psychology, and Scientific Methods, 14, pp. 288-294; and Bode, B.H. (1918).
Consciousness as behavior. Journal of Philosophy, Psychology, and Scientific Methods, 15, pp. 449-453. For a review of philosophical behaviorism, see also Bawden, H.H. (1918). The presuppositions of a behaviorist psychology. Psychological Review, 25, pp. 171-190 [all reprinted in this volume]. 26. Weiss, A.P. (1925). A Theoretical Basis of Human Behavior. Columbus, OH: R.G. Adams & Co. [reprinted in this series]. Here Weiss summarized views developed in papers published between 1917 and 1925: See Weiss, A.P. (1917). Relation between structural and behavior psychology. Psychological Review, 24, pp. 301-317; Weiss, A.P. (1917). Relation between functional and behavior psychology. Psychological Review, 24, pp. 353-368; Weiss, A.P. (1918). Conscious behavior. Journal of Philosophy, Psychology, and Scientific Methods, 15, pp. 631-641; Weiss, A.P. (1919). The mind and the man-within. Psychological Review, 26, pp. 327-334; Weiss, A.P. (1919). The relation between physiological psychology and behavior psychology. Journal of Philosophy, Psychology, and Scientific Methods, 16, pp. 626-634; Weiss, A.P. (1922). Behavior and the central nervous system. Psychological Review, 29, pp. 329-343; and Weiss, A.P. (1925). One set of postulates for a behavioristic psychology. Psychological Review, 32, pp. 83-87 [all reprinted in this volume]; See also Wozniak, R.H. (1994c). Albert Paul Weiss and A Theoretical Basis of Human Behavior. In A.P. Weiss. A Theoretical Basis of Human Behavior. London: Routledge/Thoemmes. 
27. Dunlap, K. (1930). Knight Dunlap. In C. Murchison (Ed). History of Psychology in Autobiography. Volume 2. Worcester, MA: Clark University Press, pp. 35-61. 
28. Ibid., p. 59. See also Dunlap, K. (1926). The theoretical aspect of psychology. In C. Murchison (Ed). Psychologies of 1925. Worcester, MA: Clark University Press, pp. 309-329 [reprinted in this volume].
29. Lashley, K.S. (1923), p. 244. 
30. See Mead, G.H. (1922). A behavioristic account of the significant symbol. Journal of Philosophy, 19 pp. 157-163 [reprinted in this volume].
31. Dashiell, J.F. (1928). Fundamentals of Objective Psychology. Boston: Houghton Mifflin Company.
32. Dashiell (1928), p. 10.
33. Weiss (1925), pp. 137-138.
34. Dashiell (1928), p. 51.
35. See Wozniak (1993b).
36. Watson (1919), p. 24.
37. Dashiell (1928), p. 10. It is important to note, however, that discussion of method in Dashiell's text far exceeds discussion of results. For many years, objective method was merely a promissory note. See also Wozniak (1994b).
38. Watson (1913).
39. Watson (1919), p. 10.
40. Dashiell (1928), p. 570.
41. See, for example: Ibid., p. 27.
42. Weiss (1925), p. 133.
43. See Watson (1913). For an interesting argument concerning Watson's changing views in this regard, see Logue, A.W. (1985). The growth of behaviorism: Controversy and diversity. In C.E. Buxton (Ed). Points of View in the Modern History of Psychology. Orlando: Academic Press, pp. 169-196.
44. Dashiell (1928), p. 22.
45. Watson (1919), pp. 9-10. In actual fact, however, Watson's view was more complex than this. See Wozniak (1994a).
46. Dashiell (1928), pp. 31-41.
47. Watson (1919), in which he used this taxonomy as the basis for certain chapter divisions.
48. Ibid., p. 194.
49. Ibid., p. 195.
50. Ibid., p. 231.
51. Allport (1924), see particularly Chapter 13; see also Wozniak (1994b).
52. Dashiell (1928), see especially pp. 370-372, 394-396, and 527-529.
53. Ibid., p. 522.
54. Ibid., p. 391.
55. Allport (1924), p. 55.
56. Weiss (1925), p. 252. 
57. Watson (1919), p. 14. 
58. They were not, though, for the most part characteristic of the structuralist tradition against which behaviorism most clearly defined itself. 
59. It is worth noting that when Woodworth (1924) set out to characterize his "four varieties" of behaviorism, two of the four features on which he focused-the animal behavior program and concern with the social-were actually only areas of emphasis for behaviorism. A third feature-objectivism-was widely shared outside behaviorism; and the fourth-neuromechanical reduction-was widely disputed within behaviorism. It is hardly any wonder, therefore, that Woodworth found it difficult to pin behaviorism down.
60. Dashiell (1928), p. 33. 
61. Watson (1919), p. 194. 
62. Dashiell (1928), especially Chapter 8 on native reaction patterns. 
63. Weiss (1925), especially Chapter 4 on the development of the individual. 
64. Allport (1924), especially a long section of Chapter 3 on the prepotent reflexes and learning, pp. 49-83.
65. Hamilton (1925), especially Chapter 12 on prepubertal sexual behavior. 
66. Dashiell (1928), p. 79.
67. Ibid., p. 178.
68. Allport (1924), p. 40.
69. Watson (1919), pp. 296-297. 
 70. Allport (1924), pp. 147-148.
71. Ibid., p. 148. 
72. Dashiell (1928), p. 455.
73. Weiss (1925), p. 297.