Physiognomy

“ From a physiological point of view, those metaphysical phenomena of thought, consciousness, and intelligence, which serve for the various manifestations of the human soul, are nothing but ordinary vital phenomena, and can result from nothing but the action of the organ that expresses them. We shall show that, in fact, the physiology of the brain, like that of all the other bodily organs, is deduced from anatomical observations, from experiments conducted physiologically, and from the teachings of pathological anatomy. ”

“ In recent times physiology has indeed made great, and to many startling, advances in the direction of connecting mental phenomena with brain-changes. Physiologists have established the correlation of physical and chemical with vital forces, and probably of vital with mental forces. They have proved in every act of perception the existence of a vibratory thrill passing along the nerve-cord from sense-organ to brain; and in every act of volition a similar vibratory thrill from brain to muscle ”

“ But, more than this, it may be truly said that the roots of every system of philosophy lie deep among the facts of physiology. No one can doubt that the organs and the functions of Sensation are as much a part of the province of the physiologist as are the organs and functions of motion, or those of digestion; and yet it is impossible to gain an acquaintance with even the rudiments of the physiology of sensation without being led straight to one of the most fundamental of all metaphysical problems. ”

“ Anatomy shows us that animals and plants are wonderfully constructed. But after we understand their architecture and even their minute structure, the questions remain: What are all the organs and tissues for, and what takes place within the parts that are actually alive? Physiology attempts to answer questions of this nature. It therefore stands in contrast with anatomy and is supplementary to it. The activities of the body are varied and depend on life for their manifestation — they may be called vital activities. Physiology embraces a study of them all. ”

“ But since natural selection explains the origin of the nervous apparatus, and since, given the apparatus, a definite complex of conditions necessarily evokes a definite external movement, it follows that every voluntary act, regarded solely on its physiological side, is completely explicable in accordance with the principles of physico-chemical science.
Approaching the problem from the psychological side, we find, if we look solely to the facts of consciousness, that what is given is not an individual substantive will, but only a great number of particular volitions. ”

“ Thus the two sciences of astronomy and physiology discovered and developed the methods of investigating mental times; the further development was the task of psychology.
Another source of the new psychology is to be found in the physiological study of the sense organs. The most obvious method for determining the functions of the nerves and end organs of the skin—the nose, the ear, or the eye—is to ask the living subject what he feels when various stimuli are applied. In this way there has arisen a large body, of knowledge concerning the sensory functions of the nervous system. ”

“ On this subject, physiology teaches the general fact that memory reposes upon a nervous property or power, sustained, like every other physical power, by nutrition, and having its alternations of exercise and rest. It also informs us that, like every other function, the plasticity may be stunted by inaction, and impaired by over-exertion.
As far as pure physiology is concerned, I invite everybody to reflect on one circumstance in particular. The human body is a great aggregate of organs or interests—muscles, digestion, respiration, senses, brain. ”

“ Turning to the physical side of physiology, it is unnecessary here to say more about the means employed for studying the properties of muscle and nerve than that many of the phenomena occur with such extreme rapidity that they can only be perceived by the photographic plate. In the study of the large organs, the physiologist finds a fascinating employment in devising models in which, so far as possible, all the physical conditions are reproduced, and this not only for the benefit of his pupils, but to help himself in perceiving their meaning. ”

“ There is a bully physiological laboratory, the sight of which, inaccessible as it is to me in my present condition, gave me a sharp pang. I have blocked out some reading in physiology and psychology which I hope to execute this winter—though reading German is still disgustingly slow.... It seems to me that perhaps the time has come for psychology to begin to be a science—some measurements have already been made in the region lying between the physical changes in the nerves and the appearance of consciousness-at (in the shape of sense perceptions) , and more may come of it. ”

“ Such speculations as I have quoted respecting the nervous fluid, proceeding from some of the greatest philosophers who ever lived, prove only that hitherto the endeavor to comprehend the mystery of perception and will, of life and thought, have been fruitless and vain. Many anatomical truths have been discovered, but, so far as our survey has yet gone, no genuine physiological principle. All the trains of physiological research which we have followed have begun in exact examination of organization and function, and have ended in wide conjectures and arbitrary hypotheses. ”

“ More particularly in the region of the physiology of the nervous system, is it justifiable to conclude from the progress that has been made in analysing the relations between material and psychical phenomena, that vast further advances will be made; and that, sooner or later, all the so-called spontaneous operations of the mind will have, not only their relations to one another, but their relations to physical phenomena, connected in natural series of causes and effects, strictly defined. ”

“ With respect to the first point, I am not aware that there is any one who doubts that, in the proper physiological sense of the word function, consciousness, in certain forms at any rate, is a cerebral function. In physiology we call function that effect, or series of effects, which results from the activity of an organ. Thus, it is the function of muscle to give rise to motion; and the muscle gives rise to motion when the nerve which supplies it is stimulated. ”

“ That understanding, when it is complete, will have been gained step by step through experiments on living animals, one of the first of which was Claude Bernard's research on vaso-motor nerves. [2]
There still remains the question, What good does physiology bring to mankind? Of the value of physiology as a not insignificant segment of the circle of universal knowledge, nothing need be said; where saying aught is necessary, it would be useless. Nor need much be said concerning the practical value of physiology as a basis for the conduct of life. ”

“ Applying this remark to physiology, we see that the nerves and brain as physical objects are not truly data; they are to be replaced, in the ideal structure of science, by the sensations through which the physiologist is said to perceive them. The passage from these sensations to nerves and brain as physical objects belongs really to the initial stage in the theory of physics, and ought to be placed in the reasoned part, not in the part supposed to be observed. To say we see the nerves is like saying we hear the nightingale ”

“ And when by the actions of such a nervous system, conceived objectively in modes of x y, and acted upon by physical forces which are conceived in other modes of x y, we endeavor to explain the genesis of sensations, perceptions, and ideas, which we can think of only in other modes of x y, we find that all our factors, and therefore all our interpretations, contain the two unknown terms, and that no interpretation is imaginable that will not contain the two unknown terms. ”

“ In the fifth place, modern physiology investigates the relation between physical and psychical phenomena, on the assumption that molecular changes in definite portions of nervous matter stand in the relation of necessary antecedents to definite mental states and operations. ”

“ We must suppose, in short, that physical processes constitute a locked system, every subsequent state of which is fully accounted for by the immediately preceding state; that the nervous system is a highly complex mechanism for adapting the movements of an animal to environing conditions in a manner useful to the animal; and that consciousness is a parallel manifestation, concomitant to certain processes in the highest nerve-centres. ”

“ It is nevertheless true that to one who finds enjoyment in the study of intricate mechanisms or to one for whom that amazing sequence of events which we call life has appeal there is no more fascinating study than the study of the living body. That part of the study of the body which concerns itself primarily with activity and only secondarily with form and structure, makes up the science of Physiology. The way the body works is the central theme. ”

“ Observing daily the comparative development of brain and body, with their reciprocal influence, I traced the outlines of cerebral physiology, and the laws of sympathetic connection or correspondence between the body and the encephalon, by which, in a given constitution, I would determine from the head the development of the whole body, the peculiar distributions of the circulation, with the consequent morbid tendencies, the relative perfection of the different senses and different organs of the body, and the character of the temperament. ”

“ That the powers by which the nerves are the instruments of sensation, and the muscles of motion, are vital endowments, incapable of being expressed or explained by any comparison with mechanical, chemical, and electrical forces, is the result which we should 224 expect to find, judging from the whole analogy of science; and which thus is confirmed by the history of physiology up to the present time. We naturally, then, turn to inquire whether such peculiar vital powers have been brought into view with any distinctness and clearness. ”

“ Should we care to look for more proofs as to the validity of correlation of psychic with neural, or physical processes, we can also find it in another branch of experimental physiology, namely, physiological psychology. ”

“ The physiology of a sense, consists in an external organ,—as the eye or ear, its nerves of sensation which spread through the brain, and, the nervous fluid. To each of the senses there belongs a distinct cerebral organ, which, if deducted, leaves nothing to constitute the physiology, but the exter [Pg 18] nal organ, the nerves, and nervous fluid; such may be considered the physiology of all the senses, so far as the exciting mental perception is concerned. ”

“ If not, why should the molecular motion of the brain be yoked to this mysterious companion—consciousness? We can form a coherent picture of all the purely physical processes—the stirring of the brain, the thrilling of the nerves, the discharging of the muscles, and all the subsequent motions of the organism. We are here dealing with mechanical problems which are mentally presentable. But we can form no picture of the process whereby consciousness emerges either as a necessary link or as an accidental by-product of this series of actions. ”

“ 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. ”

“ All the experiments in physiology consist practically in the production of so many pathological conditions and states. When the physiologist makes injections, sections and stimulations by various agencies, what else does he effect if not the production of the pathological, in order to learn the physiological action of the various tissues and organs? ”

“ And when I sum, again, our results as to the human organism, all our knowledge of the fitness of the cerebral mass and each fibre of the spinal net-work to the motions of the unseen life, so far from proving thought a function of the brain, or will a shock of the nerve-power, has only refined the body into the perfect vehicle of the indwelling spirit. ”

“ Consequently, our psychology leads us into anatomy and physiology, which, probably, we have already fairly mastered. In rapid review, only, in the following chapter we shall consider the organs of man’s consciousness, the brain, spinal cord, and the senses, and try to establish some relation between the material body and its mighty propelling force—the mind. ”

“ It may be said, of course, with justice, that, so far as Psychology presents us with such routine uniformities of succession, it is a mere supplementary device for making good the defects in our anatomical and physiological knowledge. If our physiological science were only sufficiently extensive and minute, we might reasonably expect to be able to describe the whole course of human action, so far as it is amenable to mechanical law, and exhibits routine uniformity in purely physiological terms. ”

“ The question of the formation of cells, the question of the excitation of a continuous and equable motion, and, finally, the questions of the independence of the nervous system and of the soul—these are the great problems on which the human mind can measure its strength. ”

“ Let any man, who has but touched the study of physiology, consider what is involved in even the most superficial observation of the simplest facts of the nervous system: for instance, the ordinary nerve-muscle preparation that is taught to every medical student, or the microscopic structure of the spinal cord, or the Wallerian method. ”