The following text is © 1997 Robert Wozniak. All hyperlinked text links to footnotes located at the bottom of the document.


Albert Paul Weiss and A Theoretical Basis of Human Behavior

Robert H. Wozniak
Bryn Mawr College

Born in Steingrund, Schlesien, Germany in 1879, Albert P. Weiss (1879-1931) was brought to America as an infant[1]. His parents, German Lutherans, settled in St. Louis where his father worked as an architect. Little else is known about either his family or his early years beyond a report that he came from a happy and affectionate home whose members participated actively in the German/American cultural life of St. Louis. Indeed, as a young man, Weiss himself belonged to a club that met to discuss philosophy[2]. Perhaps this early philosophical interest was one factor that led to his dissatisfaction with an engraving career and decision, at a relatively late age (approximately 27), to enroll in the University of Missouri.

At Missouri, he studied physics, mathematics, and philosophy before turning to coursework in psychology. His encounter with psychology occurred literally by chance. One day he happened into a room in which Max F. Meyer (1873-1967) was unsuccessfully attempting to adjust a complex piece of apparatus. When Weiss succeeded in making the adjustment, Meyer hired him as his laboratory assistant, a position he retained throughout his work for the A.B. and M.A. degrees[3]. After 1912, when Weiss accepted a position as laboratory instructor under George Frederick Arps (1874-1939) at Ohio State, he continued to return to Missouri at periodic intervals to complete his doctoral work under Meyer. In 1916, he became Meyer's first and only doctoral student with a dissertation entitled Apparatus and Experiments on Sound Intensity[4].

Meyer had arrived at Missouri in 1900[5] after studying with Stumpf and Ebbinghaus in Berlin. Like Stumpf, Meyer concentrated much of his research in audition. He published important theoretical papers on the psychology of music[6] and on the nature of cochlear function in hearing[7], and pursued experimental studies on the aesthetics of final tones, musical intonations, and quartertone music[8]. Although Weiss also worked for a time in this area, it was not primarily Meyer's research, but his theoretical orientation-his objectivism, physiological reductionism, concern with the objective translation of subjective terms, emphasis on the social significance of behavior, and analysis of language and thinking-that was to exert a lasting influence on Weiss. As Esper summed up the relationship between the two men:

"There were strong bonds between Meyer and Weiss: Weiss had been born in Germany and...spoke German in the home of his parents; his personality was most engaging: honorable, unassuming...eager in interest in all matters of scientific and humane import, humorous; well trained in physics, chemistry, biology, mathematics, and philosophy-subjects in which Meyer found most of his American students deficient; ingenious in devising and constructing apparatus. In his early publications Weiss followed Meyer in research on tonal intensity and 'vocality,' and in applying Meyer's hydraulic theories of the ear and of the nervous system to sensory discrimination and learning. In his later publications he enlarged upon Meyer's two main philosophical-or rather, methodologicalâ doctrines: that psychology should deal only with objective data and only with behavior having social import. Meyer has said, 'I have had very little-almost no-influence on American psychology directly, but perhaps a good deal through mediation by students of Weiss.' Meyer produced one doctor of philosophy: Weiss; Weiss produced twenty-five."[9]

In 1909, Meyer was one of America's most consistent, most radical objectivists. Under the influence of Max Planck (1858-1947), who had assumed the Chair in Theoretical Physics at Berlin in 1889 and who served on Meyer's dissertation committee, Meyer drew a sharp distinction between the internal and the external points of view. While the internal, psychological point of view may yield direct, personal knowledge of psychological states, these states are accessible to others only through external manifestations in action. From the external, physiological point of view, a satisfactory understanding of behavior can be obtained in terms of neural processes without postulating the intervention of any particular mental force[10].

This objectivism and commitment to seeking the fundamental explanation of human behavior in properties of the nervous system served as cornerstones of Meyer's psychology. In 1909, when Weiss stumbled upon Meyer and into psychology, Meyer was incorporating these ideas into the manuscript for an introductory textbook, The Fundamental Laws of Human Behavior, which was to appear in 1911. In its conception, The Fundamental Laws is a remarkable book[11]. Appearing two years before John Broadus Watson (1878-1958) issued his famous "behaviorist manifesto,"[12] it has been called the first "completely behavioristic explanation of human action"[13] and to some extent it was.

Meyer rejects the explanatory use of mental states except as shorthand for the operation of complex nervous processes, emphasizes the importance of behavior, and limits the scientific value of introspection solely to "the fact that it aids us in discovering the laws of nervous function."[14] With such views Meyer's objectivism was both more and less extreme than the behaviorism that Watson was to make famous. On the one hand, unlike Watson, Meyer was an uncompromising neurophysiological reductionist. For Meyer, the explanation of behavior depends directly on what goes on in the organism -- on nervous processes that link stimuli to behaviors and that correlate with mental states. His "behaviorism," therefore, was not that of the Watsonian prediction/control, stimulus/response, empty organism variety that was eventually carried to its logical extreme by B. F. Skinner (1904-1990)[15].

On the other hand, despite his explanatory objectivism, Meyer retained the descriptive use of mental terms, at least if they could be given an objective denotation. One of the best statements of Meyer's position in this regard appeared in an attack on William McDougall's (1871-1938) Body and Mind: A History and a Defense of Animism[16]. Criticizing McDougall for reintroducing consciousness as an unknown in the equation relating stimulation to behavior, Meyer argued that:

"We need to establish definite relations between our subjective and our objective terms, so that, instead of mixing them up, we can translate the one into the other. Then only will it be possible to utilize the advances made at the present time...for the advancement of an objective science of human behavior. We must try to establish definite nervous correlates for all the specific mental states and mental functions which are used in and seemingly can not be spared from our descriptions of human life in the mental and social sciences."
[17]

Psychology, in other words, retains a descriptive use of mental terms, despite its need to find objective explanation in the nervous system, because psychology deals with human life-human life as it is described in the mental and the social sciences. Here, in embryo, is another critical component of Meyer's overall view, one that would be worked out in greater detail between 1911 and 1921, when he published another introductory text, Psychology of the Other One[18]. This component involves Meyer's strong belief that psychology deals with behavioral phenomena in both their physiological and their social significance. As Meyer himself put it: "We psychologists must often hear the (unjustified) reproach that our psychology is nothing but physiology or neurology...But we psychologists have no difficulty in distinguishing our interests from those of other biological departments. We study the organism as an organism, it is true, but only in so far as its functions have distinctly social significance."[19]

Of all such functions, the one with greatest "social significance" is that by which one organism signals to another. In human beings, this generally takes the form of speech. As a young man, Meyer had read and been influenced by Lazarus Geiger's (1829-1870) Der Ursprung der Sprache. Following Geiger, Meyer had developed the view that all thinking (including abstraction and generalization) involved "innere Sprache ['internal speech']...that speaking had its origin in the necessity for human beings to cooperate in muscular activity...[and that] since all skeletal muscular activity is governed neurologically..., all thinking is governed neurologically by mediation of speech."[20] At the same time, however, speech and thinking clearly also have social significance. Abstractions and generalizations formed in inner speech by one individual can be communicated in oral or written speech to others. In this way, the behavior of one individual can be influenced by the "thoughtfulness" of another.

These are powerful ideas and each was taken to heart by the young A.P. Weiss. Indeed, Weiss's A Theoretical Basis of Human Behavior, published in 1925, and by far the most iconoclastic text in the literature of early behaviorism[21], can easily be read as an extension of Meyer's views. This is not, of course, to belittle the importance of Weiss's contribution. In Weiss, ideas barely sketched out by Meyer-continuity between psychology and the other natural sciences, the relation between the physiological basis and social significance of behavior, the need to provide objective denotations for subjective terms, and the social import of language as a mechanism of both thought and reciprocal stimulation-receive careful, systematic attention.

A Theoretical Basis of Human Behavior is divided into three large sections prefaced by an introduction. In the introduction, Weiss defines behaviorism and indicates the overall problematic in terms reminiscent of Meyer. "Behaviorism at present," he suggests, "is merely a convenient term which more or less definitely separates those psychologists who believe that the so-called mental states cannot be classified as physical states, from those psychologists who believe that they can."[22] "If awareness, mind, will, desire, are not to be regarded as a form of energy which in some way exerts a selective action upon the situation with which I am confronted and upon my responses to them, what is the behavioristic equivalent of the conditions for which these terms stand?"[23] Behaviorism in the Meyer/Weiss mode, in other words, recognizes the existence of conditions for which mental terms are employed but strives to represent these conditions in terms of their objective equivalents.

The introduction is followed by six chapters (slightly more than one-third of the book) elaborating the fundamental principles and postulates underlying the Meyer/Weiss vision. The first two chapters are devoted to establishing physicalism-the basis for continuity between psychology and the physical sciences-and the essence of this foundational view is nicely summarized by Esper:

"From electrons and protons organized into atoms to cells organized into men to men organized, ultimately, into a league of nations, the universe is to be viewed as a continuously evolving series of more and more complex and complete integrations...the phenomena studied by psychology are complications of those studied by physics, chemistry, and biology; the principle of determinism applies in psychology as in the other natural sciences; the phenomena studied by psychology depend upon the properties of the human nervous system in its interactions with the environment; the principle of evolutionary development applies not only to biological phylogenesis but to the history of individuals and of social institutions; the data of psychological research are responses to sense-organ stimulation, or to the aftereffects of such stimulation-responses which are observable, recordable, and-ideally-quantifiable."
[24]

The following four chapters are then concerned with characterizing psychology's specific place among the natural and social sciences, a characterization that Weiss grounds in a novel distinction between the biophysical and the biosocial. "Behavioristic psychology," Weiss writes, "occupies an intermediate position [between the physical and social sciences], on the one hand investigating the effect of physical conditions on sensori-motor functions, and on the other, the effects of sensori-motor function on social organization...Thus there arise two criteria with respect to which human movements may be classified: (a) as neuromuscular effects of preceding movements, (b) as neuromuscular causes of subsequent movements. I have differentiated these two classes by the terms biophysical and biosocial."[25]

Biophysically, responses are equivalent when, "as neuromuscular effects...the physiological conditions of sensitivity, conductivity, and contractility...in corresponding receptors, neurons, and effectors"[26] are equivalent. Biosocially, responses are equivalent when they serve in similar ways as stimuli for other individuals or for the self. On this analysis, it should be evident that two biophysically equivalent responses (e.g., identical movements of the facial muscles) may differ biosocially and that one and the same biosocial effect can be produced by responses differing biophysically (e.g., writing and speaking the same message). "If the study of human behavior is to achieve a scientific status," Weiss argues, "...both the biophysical and biosocial properties must be studied."[27]

This is a very significant analysis. In suggesting that movement enters into two different sets of constitutive relationships-as neuromuscular effect and as social stimulus-Weiss is, in effect, distinguishing levels of theoretical discourse. Although every biosocially relevant response (i.e., response serving as a stimulus for others) is also a neuromuscular effect (i.e., can and must also be viewed biophysically), biosocial analysis cannot be reduced to the biophysical. Suppose, Weiss asks, "that instead of the recent discovery of the undisturbed tomb of Tut-Ankh-amen and its contents, we had found a complete set of neuro-myograms of representative Egyptians of this period...Would this type of record be regarded...as an adequate substitute for the contents of the tomb as a means for revealing the behavior or cultural history of this period?...I do not believe that any neurological insight alone will enable us to determine what the stimulating effects of a given neuro-muscular configuration will be upon other individuals."[28]

Here, in short, we have psychology clearly and systematically distinguished from physiology in terms of variation in level of discourse introduced by psychology's need to focus on movements both as neuromuscular effect and as social stimulus. Indeed, for Weiss, when behavior is viewed from the biosocial perspective, "the neuro-muscular character of a response is relatively unimportant as compared with its effect as a stimulus for other individuals...[and] physical units of measurements...are relatively inadequate to measure this stimulating effect... the individual is [therefore] classified not on the basis of physical or physiological properties but on the basis of his co-operative status in the social organization of which he is a unit."[29] This is a theoretically sophisticated view.

The second large section of Weiss's text also consists of six chapters and takes up about one third of the book. The first four chapters reintroduce and reemphasize the possibility of analyzing human response either into its anatomico-physiological elements (Weiss devotes a chapter to a fairly standard, peripheralist account of receptor, effector, and central conducting mechanisms) or its stimulating effect on others (classified as "educational, vocational, administrative, recreational, and personal...in accordance with their resemblances for producing similar behavior in others"[30]). The final two chapters, one on "consciousness," the other on "mind," are designed to set the stage for analyses of specific response categories that constitute the final section of the book.

In discussing consciousness, Weiss follows Watson in asserting that psychology defined as a science of consciousness is in trouble. "In natural science...," he points out, "controversy tends to establish agreement."[31] In psychology it has led to ever greater disagreement over the nature and status of consciousness and even the validity of its introspective technique. As Weiss puts it, "Such terms as consciousness, mind, mentality, etc., are used with great liberality by everyone except those who have tried to understand what they mean."[32] Certainly, if psychology wishes to be a science, it must eschew any conception of consciousness as "some kind of non-material force or entity, which has no physical properties but which nevertheless acts on the nervous system of man in some unknown way, so as to control his behavior in conformity with some teleological plan..."[33]

Unlike Watson, however, Weiss does not entirely reject either the term or the fact of "consciousness" itself. Rather, he retains that which is of value in "consciousness" by redefining it. "The behaviorist," he writes, "concludes, that if mental or conscious processes are regarded as particular types of chemical or physical processes of as yet unknown composition then only one entity or one system of events need be assumed..."[34] Consciousness is simply "a series of speech habits that one learns in a psychological laboratory."[35] When taken in this limited sense (as "an indirect function of the unlocalizable stimulation of obscure receptors [implicit reactions] and not [as] a description of a psychical process"[36]), introspective consciousness has a role to play in scientific research: "At the present time the type of terminology and the technique of the introspective method may help to localize and describe obscure stimuli and sensori-motor conditions more effectively than through the use of the precision instruments of the physicists."[37]

Indeed, for Weiss, it is just these "obscure stimuli and sensorimotor conditions" for which one might also employ the term "mind." "Stimuli acting on sense organs," he notes, "initiate sensori-motor processes which not only terminate in the effectors of observable biophysical or biosocial responses but also in many other internal effector systems which are obscure in the sense that they cannot be localized by the self-observer nor recorded by an observer...The implicit response is primarily a residual effect of sensori-motor variations that have occurred at some earlier time as biosocial responses."[38] "No matter how complex and involved human achievements may become," in other words, for Weiss, "they are in the last analysis the functioning of contractile elements in the individual's body."[39]

Weiss's Theoretical Basis concludes with a final section (five chapters) analyzing specific response categories and summarizing his behaviorist postulates. Accepting the challenge implicit in Meyer's doctrine of the translatability of subjective into objective terms and ever mindful of the need to operate at both the biophysical and biosocial levels of analysis, Weiss first provides a behavioristic analysis of the explicit and implicit language response in their biosocial import. He then attempts to redefine traditional categories of mental analysis (e.g., thinking, purpose, motive) in terms of the biosocial outcomes of implicit response and subvocal speech. So consistent is his application of this approach that, as he tells us, "implicit reactions and subvocal speech seem to explain everything."[40]

The language reaction, for Weiss, involves the production of particular sounds or written characters that: a) are both a response to a stimulus (frequently implicit) and a stimulus to a response (for others and for the self); and b) provide the mechanism underlying abstraction and generalization. "The actual muscles that produce the sounds, characters, or symbols," in other words, "are relatively unimportant."[41] "Because the word response is independent of the sensory nature of the stimulus," in his view, "many different stimuli may release the same word reaction. This form of behavior is known as generalization, and the process may be described as the generalizing function of language. As a behavior category generalization is a type of sensori-motor mechanism in which 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 connected, even though there is very little sensory similarity between them."[42]

Thinking makes use of such generalizations. Indeed, much of what takes place in thinking involves subvocal, language reactions. This is not, however, what defines "thinking" for Weiss. Thinking, from his perspective, is a relatively standardized response, or more properly series of responses, to a problem situation yielding a relatively conventionalized outcome. Thinking, in other words, is defined in terms of the biosocial nature of the problem solution. As he puts it, "The individual stimulus-response series is constantly being standardized by the teacher,... parents,...colleagues. As a result, the biosocial stimulating conditions under which we live establish conventionalized and standardized responses...which are more or less common to many members of the community..."[43] Fundamentally, therefore, thinking is a biosocial process yielding a biosocial product with a biosocial meaning.

Purpose is similarly defined by Weiss in terms of both implicit response and biosocial outcome: "Purpose or purposive behavior refers to the fact that...there is...an organization between the various response series belonging to a given individual, which conforms to a traditional or conventional sequence."[44] Thus, for example, doctors or lawyers act in a purposeful fashion when they act in accordance with the routines that are appropriate to doctors or lawyers. Such "sequences form parts of longer behavior life history series. The terminal responses of the sequences...are designated as the purpose or aim of the antecedent activities."[45]

Finally, motives are also biosocially defined. "The behavioristic conception of motivated behavior reduces itself to the following biophysical and biosocial conditions: (a) a complex stimulating condition, which (b) releases alternative implicit behavior series, (c) the intensification of one specific series which is an essential antecedent of (d) the biosocial category that has been intensified [...] The so-called motive is the behavior which is arbitrarily designated as the end result."[46] It is interesting to note that on this account it is almost impossible to distinguish among thinking reactions, purposive behaviors, and motivated responses. Human action, for Weiss, is a complex biosocial stimulus for others precisely because it is purposive, motivated, and thoughtful. Truly, as he indicates, "implicit reactions and subvocal speech seem to explain everything."[47]

In 1929, Weiss reissued A Theoretical Basis in a second, revised edition. Treatment of the relationship between behaviorism and metaphysics, the distinction between the biophysical and biosocial, the nature of the human response and of language reactions were all expanded in response to "the many criticisms directed against the 1925 edition."[48] Despite revision, however, the fundamental problematic remains the same. Criticizing those who attempt to give both a mentalistic and a behaviorist account, Weiss once again asks whether "the concept of mind or consciousness is a necessary concept in the scientific investigation of human behavior and human achievement?"[49] And once again, his answer is the same:

"If an attempt were made to define the term mental as carefully as the term behavior is defined, there would be no objection. But this is not done. Such terms as mind, mental process, consciousness, image, etc. suddenly appear in the context of psychological writing without any attempt at definition. It is assumed that the reader knows exactly what the writer means by these terms. Is this a safe and scientific assumption to make? I do not think we can evade this question by referring it to philosophy or metaphysics. It is a purely psychological problem and requires that we formulate the fundamental postulates upon which our science rests. As long as we do not undertake the task, psychology will be designated a pseudoscience."
[50]

Two years later, Albert Paul Weiss was dead at the age of 51. During the final years of his life, he had been bedridden with a degenerative heart ailment.[51] His premature death deprived the Meyer/Weiss perspective of its most articulate spokesman; it deprived behaviorism of one of its most systematic, most philosophically sophisticated adherents; and it deprived psychology of a leading proponent of the objective, biosocial definition (rather than abandonment) of mental terms. One wonders what the future of behaviorism might have been like had Weiss lived to continue this work.[52]


Footnotes

1. Biographical details are drawn primarily from: Bloomfield, L. (1931). Albert Paul Weiss. Language, 7, pp. 219-221; Elliott, R.M. (1931). Albert Paul Weiss: 1879-1931. American Journal of Psychology, 43, pp. 707-709; and Renshaw, S. (1932). A.P. Weiss (1879-1931). Journal of General Psychology, 6, pp. 3-7. [Back to text]

2. These details have been gleaned from a footnote in Esper, E.A. (1968). Mentalism and Objectivism in Linguistics. The Sources of Leonard Bloomfield's Psychology of Language. New York: American Elsevier, p. 175. [Back to text]

3. A.B. (1910), M.A. (1912). [Back to text]

4. Weiss, A.P. (1916). Apparatus and experiments on sound intensity. Princeton and Lancaster: Psychological Review Company. [Psychological Monographs, No. 95]. [Back to text]

5. A position he was to retain until 1929. In 1929, however, a questionnaire assessing attitudes toward extramarital sexual relations had been distributed to students with Meyer's tacit approval. Public outcry over the questionnaire led to Meyer's receiving a one-year, unpaid suspension from the University. In 1930, upon his return, Meyer had the poor judgment to engage in public criticism of the members of the University Board of Curators who had been responsible for his suspension. As a result, he was summarily dismissed from the University and never again held a regular faculty appointment. For an informative discussion of the entire affair, see Esper, E.A. (1967). Max Meyer in America. Journal of the History of the Behavioral Sciences, 3, pp. 107-131. [Back to text]

6. Meyer, M. (1900a). Elements of psychological theory of melody. Psychological Review, 7, pp. 241-273. [Back to text]

7. Meyer, M. (1899). Zur Theorie des Hšrens. PflŸger's Archiv fŸr die gesamte Physiologie, 78, pp. 346-362; Meyer, M. (1900). Karl L. SchŠfer's "Neue ErklŠrung des subjectiven Combinationstšne." PflŸger's Archiv fŸr die gesamte Physiologie, 81, pp. 49-60; Meyer, M. (1900). E. ter Kuile's Theorie des Hšrens. PflŸger's Archiv fŸr die gesamte Physiologie, 81, pp. 61-75. [Back to text]

8. Meyer, M. (1903). Experimental studies in the psychology of music. American Journal of Psychology, 14, pp. 192-214. [Back to text]

9. Esper (1967), pp. 113-114. [Back to text]

10. See Planck, M. (1950). Scientific autobiography and other papers. London: Williams & Norgate, pp. 59-75, for this argument. [Back to text]

11. See Wozniak, R.H. (1993). Max Meyer and The Fundamental Laws of Human Behavior: An Introduction. In M. Meyer. The Fundamental Laws of Human Behavior. Lectures on the Foundations of any Mental or Social Science. London: Routledge/Thoemmes Press., pp. vii-xxi. [Back to text]

12. Watson, J.B. (1913). Psychology as the behaviorist views it. Psychological Review, 20, pp. 158-177. [Back to text]

13. Pillsbury, W.B. (1929). The History of Psychology. New York: Norton, p. 290. [Back to text]

14. Meyer, M. (1911). The Fundamental Laws of Human Behavior. Boston: R.G. Badger, p. 239. [Back to text]

15. Skinner, B.F. (1938). The Behavior of Organisms: An Experimental Analysis. New York: Appleton-Century. [Back to text]

16. McDougall, W. (1911). Body and Mind: A History and a Defense of Animism. London: Methuen. [Back to text]

17. Meyer, M. (1912). The present status of the problem of the relation between mind and body. Journal of Philosophy, Psychology, and Scientific Methods, 9, pp. 365-371, p. 371. [Back to text]

18. Meyer, M. (1921). Psychology of the Other-One. An Introductory Text-Book of Psychology. Columbia, MO: The Missouri Book Company. [Back to text]

19. Meyer (1921), p. 405. Esper (1968) suggests that the "social significance" criterion may have been worked out, at least in part, in the running scientific correspondence between Meyer and Weiss. See footnote, p. 175. [Back to text]

20. Esper (1966), p. 344. [Back to text]

21. The works of Meyer excepted. [Back to text]

22. Weiss (1925), p. 5. [Back to text]

23. Ibid., p 7. [Back to text]

24. Esper (1968), pp. 175-176. [Back to text]

25. Weiss (1925), pp. 55-56. [Back to text]

26. Ibid., p. 79. [Back to text]

27. Ibid., p. 80. [Back to text]

28. Ibid., pp. 81-82. [Back to text]

29. Ibid., p. 142. [Back to text]

30. Ibid., pp. 191-192. [Back to text]

31. Ibid., p. 228. [Back to text]

32. Ibid., p. 248. [Back to text]

33. Ibid., p. 230. [Back to text] p>

34. Ibid., p. 234. [Back to text]

35. Ibid., p. 240. [Back to text]

36. Ibid., p. 241. [Back to text]

37. Ibid., p. 245. [Back to text]

38. Ibid., pp. 260-261. [Back to text]

39. Ibid., p. 282. [Back to text]

40. Ibid., p. 253. [Back to text]

41. Ibid., p. 288. [Back to text]

42. Ibid., p. 297. [Back to text]

43. Ibid., pp. 324-325. [Back to text]

44. Ibid., p. 346. [Back to text]

45. Ibid., p. 352. [Back to text]

46. Ibid., pp. 365-367. [Back to text]

47. Ibid., p. 253. [Back to text]

48. Weiss, A.P. (1929). A Theoretical Basis of Human Behavior. Columbus, OH: R.G. Adams and Company, p. ix. [Back to text]

49. Ibid., p. ix. [Back to text]

50. Ibid., pp. ix-x. [Back to text]

51. Bloomfield (1931), p. 221. [Back to text]

52. It is, of course, important to note in this regard that the objective definition of mental terms (albeit via operations of measurement rather than specification of the nature of implicit response) remained a central feature of behaviorism [see, for example, the purposive, neobehaviorist analyses of Tolman, E.C. (1932) Purposive Behavior in Animals and Man. New York: Century Company]. [Back to text]