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Popular Science Monthly/Volume 73/September 1908/The Movement Towards Physiological Psychology IV

By Professor R M. WENLEY



NOW that Herbert Spencer and Eduard von Hartmann have passed away, Wundt stands almost alone among living thinkers. The importance of his philosophical contribution ranks second only to his epoch-making career in psychology. Time forbids more than this reference to it; but I may add that, very likely, his philosophical attitude possesses a future. For he heads a rising school which holds that a main business of philosophy in present circumstances is to unify and systematize the manifold results garnered piecemeal by the positive sciences.

Born in 1832, Wundt began his academic career as a medical student at Heidelberg in 1851, and continued the same studies later at Tübingen and Berlin, where he resided at the close of Johannes Müller's professorship. In 1856 he worked for a year in the physiological laboratory at Heidelberg under Helmholtz. On the scientific side he came under the influence of Müller, Fr. Arnold (in anatomy), Hasse (in pathology), E. H. and W. Weber, Helmholtz, Lotze, Bain and Fechner. Early in life he also made acquaintance with the philosophical work of Leibniz, Kant, Herbart and Lotze. As stated above,[1] he records that, in psychology, he owes the largest debt to Kant and Herbart; this explains not a few of his later positions, especially those to which younger men, of purely experimental training, have taken exception, without over-much appreciation sometimes, I fear, of what exactly they opposed. His life-work as a teacher and investigator has lain at Zürich, and Leipzig, whither he was called in 1876, and where, in 1879, he set up the first purely psychological laboratory,[2] an example followed since by many of the great universities in all civilized lands. Unlike his predecessors, especially Weber, Helmholtz, Lotze and Fechner, he has not concentrated his attention upon this or that restricted group of psycho-physiological phenomena, but has ranged over the entire field, with the result that psychology owes to him at once that ever enters high school. its present systematic form and its definite place in the fellowship of the special sciences. For these reasons, his influence and methods have penetrated everywhere.

A bare list of his principal works suffices to exhibit the range and force of his tireless activity: "Beiträge zur Lehre von den Muskelbewegungen," 1858; "Beiträge zur Theorie der Sinneswahrnemung," 1859-62; "Vorlesungen über die Menschen-und Thierseele," 1863, 2d ed., 1892 (Eng. trans.); "Grundzüge der physiologischen Psychologie," 1874, 5th ed., 1902 (Eng. trans.); "Ueber die Aufgaben der Philosophic in der Gegenwart," 1874; "Ueber den Einfluss der Philosophic auf die Erfahrungswissenschaften," 1876; "Logik," 1880-83; "Ethik," 1886, 2d ed., 1892 (Eng. trans.); "System der Philosophie," 1889; "Grundriss der Psychologie," 1898 (Eng. trans.); "Völkerpsychologie," 1900-06; and many contributions of first-rate importance to Philosophische Studien, the organ of his laboratory and philosophical circle, since 1881, the first year of its publication. When we remember that four of these books are masterpieces, and that one of them is the recognized classic in its subject, some idea of Wundt's importance emerges.

Seizing the opportunity incident to his historical position, Wundt aimed to relieve psychology from the reproach of being merely an instance of more or less loose descriptive classification. He proposed to lift it to the level of scientific explanation. By what means?

It is experiment that has been the source of the decided advance in natural science, and brought about such revolutions in our scientific views. Let us now apply experiment to the science of mind. We must remember that in every department of investigation the experimental method takes on a special form, according to the nature of the facts investigated. We can not experiment upon mind itself, but only upon its outworks, the organs of sense and movement which are functionally related to mental processes. So that every psychological experiment is at the same time physiological, just as there are physical sciences corresponding to the mental processes of sensation, idea and will. This, of course, is no reason for denying to experiment the character of a psychological method. It is simply due to the general conditions of our mental life, one aspect of which is its constant connection with the body.[3]

Or, again:

Psychology is compelled to make use of objective changes in order, by means of the influence which they exert on our consciousness, to establish the subjective properties and laws of that consciousness.[4]

Or, once more:

Physiological psychology is, therefore, first of all psychology. It has in view the same principal object upon which all other forms of psychological investigation are directed: the investigation of conscious processes in the modes of connection peculiar to them. It is not a province of physiology; nor does it attempt, as has been mistakenly asserted, to derive or explain the phenomena of the psychical from those of the physical life. We may read this meaning into the phrase "physiological psychology," just as we might interpret "microscopical anatomy" to mean a discussion, with illustrations from anatomy, of what has been accomplished by the microscope; but the words should be no more misleading in the one case than they are in the other. As employed in the present work, the adjective "physiological" implies simply that our psychology will avail itself to the full of the means that modern physiology puts at its disposal for the analysis of conscious processes.[5]

But, had he gone no farther than this, Wundt could scarcely be excepted from the condemnation of his predecessors, or from that under which some of his scholars have fallen. For, plainly, it could be objected that he had omitted the two most remarkable facts of consciousness which, stated synoptically, are its intensive or individual centralization, and its extensive development in society. These aspects of the matter tend to get beyond psychological management, as they assuredly raise ultimate philosophical problems. Wundt's high distinction is attributable mainly to his recognition of and attack upon these difficulties. So, his psychology offers a second, and broader, side, set forth, for example, in his excursus entitled "Philosophie und Wissenschaft" ("Essays," 1881), and present as a constructive, possibly a disturbing, element, in his entire purview of the psychological field. For instance, in his "System," the theory of the "growth of mental values" bears precisely upon these questions. "Mental life is, extensively and intensively, governed by a law of growth of values: extensively, inasmuch as the multiplicity of mental developments is always on the increase; intensively, inasmuch as the values which appear in these developments increase in degree."[6] And, on the strictly psychological side, he takes note of the same things as follows:

We may add that, fortunately for the science, there are other sources of objective psychological knowledge, which become accessible at the very point where the experimental method fails us. These are certain products of the common mental life, in which we may trace the operation of determinate psychical motives; chief among them are language, myth and custom. In part determined by historical conditions, they are also, in part, dependent upon universal psychological laws; and the phenomena, that are referable to these laws form the subject-matter of a special psychological discipline, ethnic psychology. The results of ethnic psychology constitute, at the same time, our chief source of information regarding the general psychology of the complex mental processes. In this way, experimental psychology and ethnic psychology form the two principal departments of scientific psychology at large. They are supplemented by child and animal psychology, which, in conjunction with ethnic psychology, attempt to resolve the problems of psychogenesis. . . . Finally, child psychology and experimental psychology in the narrower sense may be bracketed together as individual psychology, while animal psychology and ethnic psychology form the two halves of a generic or comparative psychology.[7]

So far the extensive development. On the side of intensive centralization Wundt's doctrine of apperception provides the necessary hypothesis. To these aspects of the subject I can only refer now.

Turning at once to the "Physiological Psychology," we find that it proceeds, as scientific method dictates, from the simple to the complex. After an introduction, Part I. discusses the bodily Substrate of the Mental Life; Part II. the Elements of the Mental Life; Part III. the Formation of Sensory Ideas; Part IV. the Affective Process and Volitional Action; Part. V. the Course and the Connection of Mental Processes; Part VI. adds Final Considerations. Thus, we pass from the functions of the nervous system, by way of sensation, feeling and presentation, to consciousness in the formation of ideas and in the train of ideas, which, in turn, involves attention, apperception, and will, not forgetting phenomena such as association, imagination and emotion. Two reasons make it hard to select this or that, and to say, Here Wundt excels. First, profuse wealth of suggestion and result is scattered everywhere. Second, the successive editions of the "Physiological Psychology "constitute the life history of Wundt's own mind in relation to the subject as a whole; and only psychologists von Fach can supply the necessary light and shade. It appears to me that special interest attaches to his discussion of Müller's theory of specific energies, because it reveals Wundt's view of the part played by the nervous system in the psychological organization; to his criticism of the Young-Helmholtz theory of color, because it attacks the "mystery" of space-perception; to the treatment of sensation, the duration of mental processes, and association, because they afford typical instances of the new data which experimental psychology can bestow upon analyses of psychical phenomena. Doubtless, professed psychologists would insist upon other points. For my part, the central interest still attaches to Wundt's theory of apperception and will. I take the former as a typical illustration of the direction in which physiological psychology moves.

In apperception the conscious being brings his entire unity of experience to bear on the object now in the field of his attention. We light upon an inner and elaborative activity which "bears the stamp of spontaneity." Evidently, a process complex in the highest degree! My expert colleague, Professor Pillsbury, has analyzed it as follows: Apperception involves four elements. "(1) Increase of clearness in the idea directly before the mind, accompanied by the immediate feeling of activity; (2) inhibition of other ideas; (3) muscular strain sensations, with the feelings connected with them, intensifying the primary feeling of activity; (4) the reflex effect of these strain sensations, intensifying the idea apperceived."[8] Despite this complexity, the apperceptive theory posits fundamentally a necessary "original activity," or "psychical energy," which arises from within consciousness and transforms, as by a synthesis, what, for convenience sake, may be termed simple factors. Physiological stimulus pales, and subjective transitiveness becomes determining. This activity has close connection with will, often with choice. How can it be explained? With Wundt the term consciousness possesses a special and restricted meaning. It consists of all contents, such as feelings, ideas, excitations of the will, and—there is no underlying substance or occult being. This represents the analytic aspect; the synthetic remains to be reckoned with. Now, the spontaneous activity of the mind itself, whereby presentations come to be distinguished clearly, appears as appercipient attention, when brought to play upon perceptions or upon the "stream of consciousness," and as volition, when it originates movements of the body. Obviously, the former is the more fundamental, because, in it, I connect my ideas with my will. It "depends, on the one hand, upon the stimuli then at work; and, on the other hand, upon the total state of consciousness, bow it is made up that is, by present impressions and prior experiences. . . . If we would describe more nearly what it is that we experience in ourselves when pleased or pained we can not do this more concretely than by denoting pleasure as a straining after, and pain as a straining against, an object."[9] We may say, then, that apperception means will brought to bear upon states of consciousness and then directed to external muscular acts. For, "there is absolutely nothing outside man or in him which we can call wholly or entirely his own except his will."[10] So Wundt finds the existence of a synthetic activity of consciousness beyond the range of mere association. Without going far wrong, we might term this the single faculty into which all the faculties of the old psychology are absorbed. For it compares and selects among conscious states; or peradventure, it can be described as a species of conscious striving. Here, then, the mental unity presents its distinctive, differentiating nature, and, as some have indeed supposed, might be held exempt from the persistent sapping of psychophysiological method, secluding itself within its unattainable citadel. But this is a complete mistake; and I take the opportunity to call attention to Wundt's modern position even here, a pronouncement the more necessary that he has been so frequently misunderstood, strangely enough, by those who ought to know better. Apperception, or what you please, happens to be an undoubted fact of mental life. Accordingly, it must submit to experimental treatment. A process exists, therefore analysis is free to track it to its lair. And, especially when the problem of duration raises its head, as it does inevitably, a cumulative series of experiments is in strict order.

What happens when apperception occurs? Generally, of course, a transformation of sensory into motor activity. In detail, according to Wundt, a train of processes has supervened, viz.: (1) Transmission from the sense-organ to the brain; (2) entrance into the "field of view," that is, existence of simple perception; (3) entrance into the "point of view," when perception becomes discernment; (4) activity of will, with innervation of the central organism through the motornerves, and (5) the resultant excitation of the muscles. Plainly, the crux hides in (3), which is purely psychological, while the others have a clear physiological reference. Nevertheless, (3) happens to be so surrounded by physiological phenomena that it is open to observation and experiment and these methods have been concentrated upon a research into the cerebral changes which accompany perception, apperception and will, respectively.[11] These experiments, although elaborate, and becoming more elaborate, may be classed under three heads. (1) The investigation of simple physiological time, that is, when the subject is aware of the coming impression, but is ignorant just when it will take place. (2) Those in which even this element of ignorance is eliminated. (3) Those in which modifications are possible widely, because, for example, the subject does not know what the impression will be, or is unaware of the character of the stimulus in such a way that he does not know how precisely he will be called upon to register it. In combination, these experiments show, as Wundt infers, that the exact moment of appercipience is dependent upon the self-accommodation of the subject, particularly in the matter of attention. Take the third case:

An indicator is kept moving at a uniform rate over a graduated scale, and so situated that the place of the needle can be clearly seen at each instant of time. The action of the same clock which moves the needle causes a sound at any moment, but in such a way that the subject of the experiment does not know when to expect it. With what position of the needle, now, will the sensation of sound be combined? Will the sound be heard exactly when it occurs, as indicated by the needle; or later than its real time ("positive" lengthening); or earlier than its real time ("negative" lengthening)? The result shows that one rarely hears the sound without either positive or negative displacement of it; but most frequently the lengthening is negative—that is, one believes one hears the sound before it really occurs as measured by the indicator.[12]

In this connection, then, the fundamental problem of physiological psychology is, "to determine the simple reaction-time, and from it to find the factors of psycho-physical time—namely, perception-time, apperception-time (or discernment-time), and will-time."[13]

Along this line laboratory investigation has been able to show that the will does, as a matter of record, occasion changes in the central physiological mechanism, and that these changes possess quantitative differences having more or less definite relation to psychical activity. By this I understand that the latent energy of the nerve-cells is summoned to activity, and that, as a result, the brain labors hard. In our own laboratory I have seen the subject of an attention experiment pour with perspiration, although physically he was, to all appearance, quite quiescent. No better proof of intense cerebral work could be desired. And experiment simply attempts to relate this energizing to the concomitant psychological states.

But Wundt has committed himself to the modern attitude even further. In the first and second editions of his "Physiological Psychology," he suggested that the frontal regions of the brain are related to apperception as the "bearers of the physiological processes which accompany the apperception of the presentations of sense."[14] In other words, all stages of the apperceptive process are accompanied by a fixed physiological activity. Beyond the circumstance that this assigns a function to the frontal regions which, otherwise, stand out of distinct relation to the factors of consciousness, it must be regarded as a speculation. Wundt himself, although he does not dismiss the hypothesis, tends to minimize it from his third edition. Yet it serves to show how persistently he clings to the true psycho-physiological method even in regard to the most recondite operation of the mind.

It remains to note that the influence of mind over body demands study as much as the converse. If apperception be a legitimate supposition—and it would seem to be a hypothesis which at least accounts for unquestioned facts, then it follows that we must estimate it, not by external stimulus, but in terms of internal activity. And this, of course, reminds us that psycho-physiological investigation has proved the existence of an influential voluntaristic element. No doubt, to this point, the former has claimed, and still claims, the lion's share of experimental attention. So that, in many ways, the internal problem awaits concentrated attack. That is to say, physical and physiological problems, being so much more readily amenable to the new methods, have tended to crowd out the distinctively psychological material. Nevertheless, we have arrived at something analogous to a causal influence of the central nervous system upon what I shall call ideation. This was the indispensable initial step. But yet, this causality is necessarily in consciousness, and, in so far forth, is not causal at all. For, of nervous states as such we do not know anything, and never can know anything. Accordingly, the other side proffers its claim, which, in the light of this agnosticism, is very far from being modest. This point was admirably taken by Professor Cattell, in his vice-presidential address to the Anthropological Section of the American Association for the Advancement of Science, in 1888:

Much is being written just now regarding the relation of consciousness to the brain. The question is: Do perceptions, thoughts, feelings, volitions, stand in causal interaction with the brain, or are they an epiphenomenon, accompanying changes in the brain but not influencing them? Are our ordinary actions complex reflexes due to physical stimuli and the structure of the nervous system, or are the changes in the brain that precede movements initiated and directed by consciousness? The question is one of facts that should be settled by scientific methods; and the solution will by no means concern psychology alone. The two greatest scientific generalizations of the present century are the conservation of energy and evolution by the survival of the fit. Now, if consciousness alters, however slightly, the position of molecules in the brain the fundamental concept of physical science must be abandoned. If consciousness have no concern in the actions of the individual we have one of the most complex results of evolution developed apart from the survival of useful variations, and the Darwinian theory has failed.[15]

We conclude then with the startling reflection that psychology is the keeper of a tremendous oracle. And, on the whole, the oracle keeps silence still.

  1. Article I.
  2. I am not forgetting James's laboratory at Harvard in 1875, which was physiological.
  3. "Human and Animal Psychology," p. 10 (Eng. trans.).
  4. Philos. Studien, I., p. 4.
  5. "Physiological Psychology," Vol. I., p. 2 (Eng. trans.).
  6. "System der Phil." (2d ed.), p. 304.
  7. "Physiol. Psych.," Vol. I., pp. 5-6 (Eng. trans.).
  8. Am. Journal of Psych., Vol. VIII., part 3.
  9. "Physiol. Psych.," p. 535, Vol. I. (3d ed.)
  10. System d. Phil.," p. 387.
  11. Cf. Cattell in Mind, XIII, pp. 37 ff. (old series), and Titchener in ibid., I., pp. 206 ff. (new series).
  12. "Elements of Physiological Psychology," Ladd, p. 488.
  13. Ibid., p. 472.
  14. Second edition, Vol. I., p. 218.
  15. P. 12.