“For moderate irritation of a limited part of the skin with a certain mean degree of excitability draws after it a reflex contraction only in that group of muscles which is provided with motor roots, issuing at the same elevation and on the same side as the irritated sensory fibres. If the stimulus or irritability increases, the excitement also first passes over to the motor root-fibres of the other half of the body which issue at the same height; lastly, with still greater increase it spreads with increasing intensity first up and then down” (the former on the sensory, the latter on the motor paths of the spinal cord), “so that finally the muscles of all parts of the body, which receive their nerves from the spinal cord and medulla oblongata, are sympathetically affected. Accordingly, every sensory fibre by means of a branch path of the first order stands in connection with the motor fibres arising on the same side and at the same level, by one of the second order with those emerging on the opposite side at the same level, by branches of the third order with those emerging higher up, and finally by that of a fourth order also with those arising far lower down” (Wundt, pp. 116–117). While with increasing intensity of stimulation greater resistances are overcome (or with increasing irritability all resistances reduced), the branch paths of the higher orders must pari passu be brought into requisition; and in the same proportion also increases the number of the central intermediate links concerned in the total motor reaction. This increase now takes place very rapidly as we pass from the spinal cord to the co-operation of the higher centres; the reflexions then increase in complication in quick progression, without thereby losing their reflex character.
However, then, one may look at the matter, the conclusion is not to be resisted that all the functions of the central nervous system, and therewith all our manifestations of life and mental activity, fall under the conception of reflex action. We must make this thought entirely our own, when it loses the character of a paradox. It imports, in fine, nothing more than the axiom of sufficient reason in metaphysics. If the latter be translated into the language of nervous physiology it runs, “No ganglionic cell is functional without a sufficient reason, which is called a stimulus;” and translated into the language of psychology it runs, “No volition without motive.” Both are familiar self-evident truths, but which perhaps open up a fruitful prospect if we bring them into connection by help of the notion “reflexion” under the point of view of physiological psychology. We have, namely, before us the problem to make internal experience more intelligible by means of the external, and conversely.
The physiologist causes his beheaded and poisoned frog to make a movement of contraction, and thereby obtains indubitable evidence that the relatively simple reflex action observed rests on a mechanism. The psychologist sees in motivation a reflex act, and gains the equally indubitable conviction that reflexion is a psychical process in which a volition uniformly follows on a sensation in accordance with the true nature of the character. The physiological psychologist, as soon as he perceives that the essence of reflexion must in both events be homogeneous, has to advance to the conclusion, “Consequently reflex contraction is a volition excited by sensation in the particular centre, and the genesis of volition is a mechanism conformable to law.” The materialistic physiologists do not need much pressing to accept the last half of this conclusion; but per contra the first, although they cannot fail to see that logically they must allow either both or neither. For the rest, psychology long ago dreamt of a “physiological psychology,” talked of a statics and dynamics of desires and ideas; and after all nothing is excluded by the admission of the mechanics of reflexion but the indeterminism of the will, long ago perceived to be untenable. If one once admits that the subjectively psychical acts correspond to objectively material functions, of course all objective mechanics of molecular motions in the nervous system must correspond to the subjective mechanics of desires and ideas, and conversely. All the more astonishing must it, however, appear when the physiologists, who confirm this afresh, will not see the psychological reverse of their apparently materialistic medal, namely, that every, even the smallest, reflex action is a volition which is motived by a sensation. Sensation is only so far as it becomes conscious (certainly, however, only becomes conscious for the particular ganglionic cell or the centre in question); volition stands in and of itself beyond all consciousness; and whether in the particular case it appears in consciousness formally as intensive feeling of innervation, or materially as qualitative perceived motion, is dependent on circumstances, and in any case highly improbable for simpler reflexes in subordinate centres.
Wundt has precluded himself from this insight both by his above-mentioned prejudice in regard to consciousness, as also by his distorted conception of the will. His remark is correct: “If one tries to determine where the mechanism ceases and where the will begins, the question is altogether falsely proposed. For one here opposes conceptions to one another which are not opposites at all” (p. 822). But he does not draw from this the unavoidable inference that in that case either sensation and will, in defiance of internal experience, must be denied even in the highest mental functions, or they must also be admitted in the lowest reflex processes, because both sides are related to each other as inner and outer. Were these notions “a mere fiction” (ibid.) in the latter case, they must be so also in the former; were that inner, psychical side of the process and the metaphysical substance of an “unconscious soul” which supports it after the admission of the external mechanism in the simple reflexion “a superfluous and meaningless addition” (ibid.), it would be so also in the achievements of the genius and the hero.
Maudsley comes very near the truth, but he is too much of an Englishman to grasp what is apparently so paradoxical with a firm hand. He says: “Wherever an afferent nerve issues from the cell or group of cells in the cortical layers of the hemispheres, and an efferent nerve issues from the cell or group of cells, there is the possible or actual centre of a particular volition; … volition or will simply expresses the due co-ordinate activity of the supreme centres, not otherwise than as the co-ordinate activity of the spinal cord or medulla oblongata might be said to represent its will” (p. 444).
This not merely “might,” but “must” undeniably be said, if one desires to be a physiological psychologist in the true sense of the word, and would not by such timidity in drawing conclusions forfeit the right of inference in a reverse direction, namely, from the physiological to the psychological aspect of phenomena, from material to psychical mechanics. Maudsley had the less reason to evade the acknowledgment of a will in the lower centres, as he even admits the necessity of the perception of the stimulus in the same, which indeed requires the genesis of a consciousness, which the will does not. On the other side, the unwonted step is made more difficult for him, in the first place, by the English not having, as the German, two different designations for Wille and Willkür; and, in the second place, because, like a true English empiricist, he entertains an almost superstitious dread of treating the abstract conception of the will as an ideal entity, i.e., of straying into the province of metaphysics.1
In this question also it holds good that for comprehending the complicated events in human consciousness a sure foundation for judgment must be gained from the simple relations in lower animals. On this point Maudsley himself writes as follows: “The simplest mode of nervous action in man, comparable to that of the lowest animals that possess nerve, is exhibited by the scattered ganglionic cells belonging to the sympathetic system which are concerned in certain organic processes. The heart’s action, for example, is due to the ganglionic cells diffused through its substance. Meissner has shown that nerve-cells disseminated through the tissues of the intestines govern their motions; and Lister thinks it probable that cells scattered in the tissues preside over the contractions of the arteries, and over the remarkable diffusion of the pigment granules which takes place in the stellate cells of the frog’s skin. The separate elements of the tissues are co-ordinated by the ganglionic ne
rve-cells of the sympathetic system; and these co-ordinating centres, again, are found to be under the control of the cerebrospinal centres. In the spinal cord the ganglionic nervecells are collected together, and so united that groups of them and connected groups of them become independent centres of combined movements, simultaneous and successive, in answer to stimuli; this arrangement representing the entire nervous system of those animals in which no organs of special sense have yet appeared” (p. 108).
Only those who “have applied to the lower animals their subjective misinterpretation of the complex phenomena in man” (p. 139), will be prepared to dispute that these lower animals have sensation and will; for the common objection, that in these organisms all vital manifestations are only reflexes, no longer avails, since we have perceived the like in the highest mental functions. On the contrary, it is precisely the lowest animals that are suited to demonstrate visibly, as it were, that every reflex action even of the simplest ganglionic cell has just as much a subjective and psychical as an objective and physical side, and that the former again falls into a conscious and an unconscious psychical part. The stimulus or the motive must be conscious in the ganglionic cell as sensation if it is above the threshold; the reaction of the will or the result of the reflex process, looked at from within, only becomes conscious at higher stages of intelligence by comparative reflexion; the passage from stimulation to reaction, from motive to volition, the properly punctum saliens in reflexion, remains for ever concealed from the light of consciousness; and yet there lies therein just the enigmatic problem, Why then does this particular sensation act as a motive to this volition?
The materialistic conception finds the answer very easy by simply seeking the reason in the objective physical mechanism of the movements. But that means allowing the two-sidedness of a psychical and physical character only to the first and last term of the process, and refusing it to the middle term, the spark which passes from one to the other; in other words, it means degrading the psychical factor in the reflex to the dead passivity of a mere mirroring of certain members of the then alone actual external process, or the depressing of the psychical to a sort of accidental appendix of the external event, which in certain phases of the latter emerges in an inexplicable fashion.
In opposition to such an external conception it must be remembered that the objective material event, just as the inner events of consciousness, are only two parallel and polar-opposed phenomenal forms of one existence revealing itself in both, which is always more transparent to the view from the subjective than the objective side, because the former view is at any rate a direct one, but the latter only mediated by the subjective appearance of the objective phenomenon. Whether there is an objectively real physical process, apart from a consciousness apprehending it, is at the very least a disputed question, which is even answered in the negative by the idealistic theory of cognition; but even if the Realism which affirms it is in the right, it is so only on the ground of inner subjective phenomenal experience, which is equally indisputable for idealists as realists. To the latter consequently appertains once for all the higher certainty; on it alone can the realistic belief in an external reality be supported, and every inference of the latter, which leads it to a negation of the certainty of immediate inner experience withdraws from under itself the ground on which it stands. Therefore psychological experience must always remain the immutable standard by which the supposed external experience and the inferences therefrom have to be verified.
The being underlying the appearance begins for the inner psychological series of events just where consciousness ceases, and the unconscious-psychical foundation of the consciousness of the sensation is itself that which, turned towards others like itself, constitutes the objective phenomenon. This unconscious-psychical foundation of the reflex process in the ganglion-cell is, however, definable most accurately as a will, which is subject to a law such that a certain motive determines it to a certain volition. (It remains here perfectly obscure whether this will is a result of the combination merely of the molecular wills of the cell, or whether other volitional factors enter into it in addition.) In no case is it justifiable to ignore this unconsciously psychical foundation, and to affix the subjective inwardness as accidental appendix of certain moments of the external physical process, which is itself only objective phenomenon. Volition is a psychical act not merely in its conscious or unconscious existence (as result of material mechanics, as Materialism supposes), but also in the whole history of its origination as due to the psychical motive and the law of its psychical reaction.
5. The Teleological Character of the Reflex Function .—The most certain proof of the inner psychical side of the reflex process is the teleological character of this reaction, which is expressed in the thoroughgoing purposiveness of the physiological (not pathological) reflexes.—As a matter of course, this purposiveness cannot take place with a scale of stimulation unlimited above and below. As our ear in the deepest tones does not hear a tone, but a droning noise, in the highest is aware no longer of a tone, but of an acute pain, as our eye does not distinguish objects with a very feeble illumination, and is dazzled and destroyed by a brightness all too bright, without the adaptation of these organs being thereby defective, the purposive reflexes can also be looked for only within certain finite limits of the scale of stimulation, but these limits will themselves again be teleologically determined. Should the centres react on all too feeble stimuli, they would, as a morbid centre actually does, squander their store of force by reason of the weak stimuli ceaselessly playing around them, instead of sparing it for the uses where its expenditure is of value for the life of the organism. On the other hand, should the centres be constituted so solidly and firmly that even the most violent attacks could not disorganise them, they would possess a constitution, which would make them less suited to their more delicate offices, without ever satisfying the intrinsically absurd demand of an absolute indestructibility. The fact that abnormally strong stimuli produce convulsions in the centres and act in a disorganising fashion is therefore just as little as the other fact, that the suitable reaction only begins with a certain intensity of stimulation, calculated to render doubtful this teleological character of the reflexes, but rather only serves to set it in the true light.
Further, it is to be noticed, as we said above, that with increasing strength of the stimulus ever more and higher centres are drawn into action; hence it results that the character of the reaction must change with the intensity of the stimulus. But even this does not tell against, but for the purposiveness of the reflexes; for it is precisely for the good of the organism that it does not respond to weak stimuli merely with weaker, but also with other motor reactions, than to strong stimuli, which act at the same point. These purposive differences, now, are reached by the threshold of stimulation being different for the reflex actions of the different centres. With the weakest stimulus only the centre in which the particular sensory nerve immediately terminates solicits to reflexion, and the consequence is a simple contraction, which, e.g., suffices to drive away a fly from the hide of an ox, or to push aside the oppressive fold of a man’s dress, or to change the uncomfortable position of a leg during sleep.
Purposeless, therefore, the reflexes cannot be called even with the weakest stimuli above the threshold (as by Wundt, p. 823); only the motor sphere of innervation for the centre, which alone reacts on the weakest stimuli, is a confined one, and therefore also the change of the external circumstances to be effected by it very narrowly limited. As more and higher centres are reached by the propagated stimulus, this motor sphere of innervation of all the centres sharing in the reflexion extends, and therewith the possibility of combined muscular movements to change the external situation announced by the stimulus. To the sphere of motor innervation governed by a central spot must the impulses of innervation proceeding from it of course correspond, if they are not inadequate from the very first, and therefore to be called unsuitable, and therefore, in fact, for a s
ingle ganglionic cell that reflex action which is teleologically demanded is a quite other one than for a larger group of ganglionic cells acting in concert, and for a cell in the lower part of the spinal cord quite other than for one in the upper, and for this again another than for one in the medulla oblongata. The reaction can only be called purposive at any point when it has regard to the maximum of what is attainable from this point. This is not sufficiently estimated by Wundt, whilst he cannot of course avoid the acknowledgment of the too evident purposiveness in the case of mean intensities of stimulation.
“A decapitated frog moves its leg against the pincers with which it is irritated, or it wipes away with its foot the drop of acid applied to its skin. It sometimes tries to withdraw from a mechanical or electrical irritation by a leap. When brought into an unusual position, e.g., placed on its back, it perhaps returns to its previous posture. Here, then, the stimulus does not introduce merely a movement in general, which spreads from the irritated part with increasing intensity of the stimulus and growing irritability, but the movement is adapted to the external impression. In the one case it is a movement of defence; in a second it aims at getting rid of the stimulus; in a third at removal of the body from the sphere of the irritation; in a fourth, finally, at restoration of the previous posture. Still more clearly does this purposive adaptation to the stimulus stand out in the experiments conducted by Pflüger and Auerbach, in which the ordinary conditions of movement are somewhat changed. A frog, for example, whose leg has been cut off on the side on which it is irritated by acid, first makes some fruitless attempts with the amputated stump, then, however, pretty regularly chooses the other leg, which is wont to remain at rest when the animal is unmutilated.1 If the decapitated frog be fastened by its back, and the inner side of one of its thighs be sprinkled with acid, it tries to get rid of the latter by rubbing the two thighs against one another; but if now the moved thigh be separated far from the other, after a few vain attempts it suddenly stretches this one out and pretty accurately reaches the point which was irritated.2 Lastly, if one breaks the upper thighs of decapitated frogs, and cauterises, whilst they are stretched on their bellies, the region of the anus, in spite of the disturbing nature of the treatment, they correctly touch the cauterised spot with the feet of the broken limbs. These observations, which may be varied in diverse ways, show that the animal entirely deprived of its brain can adapt its movements to the changed condition in a way which, if consciousness and will were concerned, would manifestly presuppose a perfect knowledge of the position of the whole body and of its several parts” (p. 824).
Philosophy of the Unconscious Page 102
