The Principles of Psychology, Vols. 1-2

The Experimental Method. But psychology is passing into a less simple phase. Within a few years what one may call a microscopic psychologj^ has arisen in Germany, car ried on by experimental methods, asking of course every moment for introspective data, but eliminating their uncer tainty by operating on a large scale and taking statistical means. This method taxes patience to the utmost, and could hardly have arisen in a country whose natives could be bored. Such Germans as Weber, Fechner, Vierordt, and Wundt obviously cannot ; and their success has brought into the field an array of younger experi mental psychologists, bent on studying the elements of the mental life, dissecting them out from the gross results in which they are embedded, and as far as possible reducing them to quantitative scales. The simple and open method of attack having done what it can, the method of patience, starving out, and harassing to death is tried; the Mind

must submit to a regular siege, in which minute advantages gained night and day by the forces that hem her in must sum themselves up at last into her overthrow. There is little of the grand style about these new prism, pendulum, and chronograph-philosophers. They mean business, not chivalry. What generous divination, and that superiority in virtue which was thought by Cicero to give a man the best insight into nature, have failed to do, their spying and scraping, their deadly tenacity and almost diabolic cunning, will doubtless some day bring about,

No general description of the methods of experimental psychology would be instructive to one unfamiliar with the instances of their application, so we will waste no words upon the attempt. The principal fields of experimentation BO far have been : 1) the connection of conscious states with their physical conditions, including the whole of brainphysiology, and the recent minutely cultivated physiology of the sense-organs, together with what is technically known as 'psycho-physics,' or the laws of ^correlation between sensations aijd the outward stimuli by which they are aroused ; 2) the analysis of space-perceptionlnto its sensa tional elements ; 3) the measurement of the duration of the simplest mental processes ; 4) that of the accuracy of re production in the memory of sensible experiences and of intervals of space and time; 5) that of the manner in which simple mental states influence each other, call each other up, or inhibit each other's reproduction ; 6) that of the number of facts which consciousness can simultaneously discern ; finally, 7) that of the elementary laws of oblivescence and retention. It must be said that in some of these fields the results have as yet borne little theoretic fruit commensurate with the great labor expended in their acquisition. But facts are facts, and if we only get enough of them they are sure to combine. New ground will from year to year be broken, and theoretic results will grow. Meanwhile the experimental method has quite changed the face of the science so far as the latter is a record of mere work done.

spective and experimental methods. This method pre supposes a normal psychology of introspection to be estab lished in its main features. But where the origin of these features, or their dependence upon one another, is in ques tion, it is of the utmost importance to trace the phenom enon considered through all its possible variations of type and combination. So it has come to pass that instincts of ; animals are ransacked to throw light on our own ; and that ^ the reasoning faculties of bees and ants, the minds of savages, infants, madmen, idiots, the deaf and blind, criminals, and eccentrics, are all invoked in support of this or that special theory about some part of our own mental life. The history of sciences, moral and political institutions, and languages, as types of mental product, are pressed into the same ser vice. Messrs. Darwin and Galton have set the example of circulars of questions sent out by the hundred to those supposed able to reply. The custom has spread, and it will be well for us in the next generation if such cir culars be not ranked among the common pests of life. Meanwhile information grows, and results emerge. There are great sources of error in the comparative method-^ The interpretation of the ' psychoses ' of animals, savages, and infants is necessarily wild work, in which the per sonal equation of the investigator has things very much its own way. A savage will be reported to have no moral or religious feeling if his actions shock the ob server unduly. A child will be assumed without self-con sciousness because he talks of himself in the third person, etc., etc. No rules can be laid down in advance. Com parative observations, to be definite, must usually be made to test some pre-existing hypothesis ; and the only thing / j\ then is to use as much sagacity as you possess, and to be 7 as candid as you can.

The first of them arises from the Misleading Influence 0} Speech. Language was originally made by men who were fSlf^psychologists, and most men to-day employ almost exclusively the vocabulary of outward things. The car dinal passions of our life, anger, love, fear, hate, hope, and the most comprehensive divisions of our intellectual activity, to remember, expect, think, know, dream, with the broadest genera of aesthetic feeling, joy, sorrow, pleasure, pain, are the only facts of a subjective order which this vocabulary deigns to note by special words. The elementary qualities of sensation, bright, loud, red, blue, hot, cold, are, it is true, susceptible of being used in both an objective and a subjective sense. They stand for outer qualities and for the feelings which these arouse. But the objective sense is the original sense ; and still to-day we have to describe a large number of sensations by the name of the object from which they have most frequently been got. An orange color, an odor of violets, a cheesy taste, a thunderous sound, a fiery smart, etc., will recall what I mean. This absence of a special vocabulary for sub jective facts hinders the study of all but the very coarsest of them. Empiricist writers are very fond of emphasizing one great set of delusions which language inflicts on the mind. Whenever we have made a word, they say, to denote a certain group of phenomena, we are prone to suppose a substantive entity existing beyond the phenomena, of which the word shall be the name. But the lack of a word quite as often leads to the directly opposite error. We are then prone to suppose that no entity can be there ; and so we come to overlook phenomena whose existence would be patent to us all, had we only grown up to hear it familiarly recognized in speech.* It is hard to focus OUT attention on \ J;he nameless, and so there results a certain vacuousness in ) the descriptive parts of most psychologies.

But a worse defect than vacuousness comes from the dependence of psychology on common speech. Naming our thought by its own objects, we almost all of us assume that as the objects are, so the thought must be. The thought of several distinct things can only consist of several distinct bits of thought, or ' ideas ; ' that of an abstract or universal object can only be an abstract or universal, idea * In English we have not even the generic distinction between thethiug-thought-of and the-thought-thinking-it, which in German is expressed by the opposition between (jedachtes and Gedanke, in Latiu by that between WQitfitum and cooitatda

As each object may come and go, be forgotten and then thought of again, it is held that the thought of it has a pre cisely similar independence, self-identity, and mobility. The thought of the object's recurrent identity is regarded as the identity of its recurrent thought ; and the perceptions of multiplicity, of coexistence, of succession, are severally conceived to be brought about only through a multiplic ity, a coexistence, a succession, of perceptions. The con tinuous flow of the mental stream is sacrificed, and in its place an atomism, a brickbat plan of construction, is preached, for the existence of which no good introspective grounds can be brought forward, and out of which pres ently grow all sorts of paradoxes and contradictions, the heritage of woe of students of the mind.

These words are meant to impeach the entire English psychology derived from Locke and Hume, and the entire German psychology derived from Herbart, so far as they both treat 'ideas' as separate subjective entities that come and go. Examples will soon make the matter clearer. Meanwhile our psychologic insight is vitiated by still other snares. 'The Psychologist's Fallacy.' The great snare of the psy chologist is the confusion of his own standpoint with that of the •mental fact about which he is making his report. I shall hereafter call this the 'psychologist's fallacy' par excellence. For some of the mischief, here too, language is to blame. The psychologist, as we remarked above (p. 183), stands out side of the mental state he speaks of. Both itself and it» object are objects for him. Now when it is a cognitive state (percept, thought, concept, etc.), he ordinarily has no other way of naming it than as the thought, percept, etc., of that object. He himself, meanwhile, knowing the self-same object in his way, gets easily led to suppose that the thought, which is of it, knows it in the same way in wrhich he knows it, although this is often very far from being the case.* The most fictitious puzzles have been introduced into our science by this means. The so-called question of presentative or representative perception, of whether an

object is present to the thought that thinks it by a coun terfeit image of itself, or directly and without any interven* ing image at all ; the question of nominalism and conceptualism, of the shape in which things are present when only a general notion of them is before the mind ; are compara tively easy questions when once the psychologist's fallacy is eliminated from their treatment, — as we shall ere long see (in Chapter XII). Another variety of the psychologist's fallacy is the as sumption that the mental state studied must be conscious of it self as the psychologist is conscious of it. The mental state is aware of itself only from within ; it grasps what we call its own content, and nothing more. The psychologist, on the contrary, is aware of it from without, and knows its relations with all sorts of other things. What the thought sees is ' only its own object; what the psychologist sees is the j thought's object, plus the thought itself, plus possibly all the rest of the world. We must be very careful therefore, in discussing a state of mind from the psychologist's point of view, to avoid foisting into its own ken matters that are only there for ours. We must avoid substituting what we know the consciousness is, for what it is a consciousness of, and counting its outward, and so to speak physical, relations with other facts of the world, in among the objects of which we set it down as aware. Crude as such a confusion of standpoints seems to be when abstractly stated, it is never theless a snare into which no psychologist has kept himself at all times from falling, and which forms almost the entire stock-in-trade of certain schools. We cannot be too watch ful against its subtly corrupting influence.

Summary. To sum up the chapter, Psychology assumes that thoughts successively occur, and that they know objects in a world which the psychologist also knows. These thoughts are the subjective data of which he treats, and their relations to their objects, to the brain, and to the rest of the ivorld constitute the subject-matter of psychologic science. Its methods are introspection, experimentation, and comparison. But intro spection is no sure guide to truths about our mental states ; and in particular the poverty of the psychological vocabu.

lary leads us to drop out certain states from our consid eration, and to treat others as if they knew themselves and their objects as the psychologist knows both, which is a disastrous fallacy in the science. SINCE, for psychology, a mind is an object in a world of other objects, its relation to those other objects must next be surveyed. First of all, to its Minds, as we know them, are temporary existences. Whether my mind had a being prior to the birth of my body, whether it shall have one after the latter's decease, are questions to be decided by my general philosophy or the ology rather than by what we call ' scientific facts ' — I leave out the facts of so-called spiritualism, as being still in dis pute. Psychology, as a natural science, confines itself to the present life, in which every mind appears yoked to a body through which its manifestations appear. In the present world, then, minds precede, succeed, and coexist with each other in the common receptacle of time, and of their collective relations to the latter nothing more can be said. The life of the individual consciousness in time seems, however, to be an interrupted one, so that the question :

becomes one which must be discussed. Sleep, fainting, coma, epilepsy, and other ' unconscious ' conditions are apt to break in upon and occupy large durations of what we nevertheless consider the mental history of a single man. And, the fact of interruption being admitted, is it not possible that it may exist where we do not suspect it, and even perhaps in an incessant and fine-grained form ? This might happen, and yet the subject himself never know it. We often take ether and have operations per formed without a suspicion that our consciousness has suf

fered a breach. The two ends join each other smoothly over the gap ; and only the sight of our wound assures us that we must have been living through a time which for our immediate consciousness was non-existent. Even in sleep this sometimes happens : We think we have had no nap, and it takes the clock to assure us that we are wrong.* We thus may live through a real outward time, a time known by the psychologist who studies us, and yet not feel the time, or infer it from any inward sign. The ques tion is, how often does this happen ? Is consciousness really discontinuous, incessantly interrupted and recom mencing (from the psychologist's point of view) ? and does it only seem continuous to itself by an illusion analogous to that of the zoetrope ? Or is it at most times as continu ous outwardly as it inwardly seems ?

It must be confessed that we can give no rigorous answer to this question. Cartesians, who hold that the essence of the soul is to think, can of course solve it a priori, and explain the appearance of thoughtless inter vals either by lapses in our ordinary memory, or by the sinking of consciousness to a minimal state, in which per haps all that it feels is a bare existence which leaves no particulars behind to be recalled. If, however, one have no doctrine about the soul or its essence, one is free to take the appearances for what they seem to be, and to admit that the mind, as well as the body, may go to sleep.

Locke was the first prominent champion of this latter view, and the pages in which he attacks the Cartesian belief are as spirited as any in his Essay. " Every drowsy nod shakes their doctrine who teach that their soul is always thinking." He will not believe that men so easily forget. M. Jouffroy and Sir W. Hamilton, attacking the question in the same empirical way, are led to an opposite conclusion. Their reasons, briefly stated, are these : * Messrs. Payton Spence (Journal of Spec. Phil., x. 338, xiv. 286) and M. M. Garver (Amer. Jour, of Science, 3d series, xx. 189) argue, the one from speculative, the other from experimental grounds, that, the physi cal condition of consciousness being neural vibration, the consciousness must itself be incessantly interrupted by unconsciousness— about fifty times a second, according to Garver.

Iii somnambulism, natural or induced, there is often a great display of intellectual activity, followed by complete oblivion of all that has passed.* On being suddenly awakened from a sleep, however pro found, we always catch ourselves in the middle of a dream. Common dreams are often remembered for a few minutes after waking, and then irretrievably lost. Frequently, when awake and absent-minded, we are visited by thoughts and images which the next instant we cannot recall.

Our insensibility to habitual noises, etc., whilst awake, proves that we can neglect to attend to that which we never theless feel. Similarly in sleep, we grow inured, and sleep soundly in presence of sensations of sound, cold, contact, etc., which at first prevented our complete repose. We have learned to neglect them whilst asleep as we should whilst awake. The mere sense-impressions are the same when the sleep is deep as when it is light ; the difference must lie in a judgment on the part of the apparently slumbering mind that they are not worth noticing.

This discrimination is equally shown by nurses of the sick and mothers of infants, who will sleep through much noise of an irrelevant sort, but waken at the slightest stir ring of the patient or the babe. This last fact shows the sense-organ to be pervious for sounds. Many people have a remarkable faculty of registering when asleep the flight of time. They will habitually wake up at the same minute day after day, or will wake punctu ally at an unusual hour determined upon overnight. How can this knowledge of the hour (more accurate often than anything the waking consciousness shows) be possible without mental activity during the interval ?

Such are what we may call the classical reasons for ad mitting that the mind is active even when the person after wards ignores the fact.f Of late years, or rather, one may * That the appearance of meutal activity here is real can be proved by suggesting to the ' hypnotized ' somnambulist that he shall remember when he awakes. He will then often do so. f For more details, cf. Malebranche, Rech. de la Verite, bk. in. chap, i; J. Locke, Essay cone. H. U., book 11. ch. i; C. Wolf, Psychol.

say, of late months, they have been reinforced by a lot of curious observations made on hysterical and hypnotic subjects, which prove the existence of a highly developed consciousness in places where it has hitherto not been sus pected at all. These observations throw such a novel light upon human nature that I must give them in some detail. That at least four different and in a certain sense rival ob servers should agree in the same conclusion justifies us in accepting the conclusion as true.

One of the most constant symptoms in persons suffer ing from hysteric disease in its extreme forms consists in alterations of the natural sensibility of various parts and organs of the body. Usually the alteration is in the direc tion of defect, or anaesthesia. One or both eyes are blind, or color-blind, or there is hemianopsia (blindness to one half the field of view), or the field is contracted. Hearing, taste, smell may similarly disappear, in part or in totality. Still more striking are the cutaneous anaesthesias. The old witch-finders looking for the ' devil's seals ' learned well the existence of those insensible patches on the skin of their victims, to which the minute physical examinations of recent medicine have but recently attracted attention again. They may be scattered anywhere, but are very apt to affect one side of the body. Not infrequently they affect an entire lateral half, from head to foot; and the insensible skin of, say, the left side will then be found separated from the naturally sensitive skin of the right by a perfectly sharp line of demarcation down the middle of the front and back. Sometimes, most remarkable of all, the entire skin, hands, feet, face, everything, and the mucous membranes, muscles and joints so far as they can be ex-

plored, become completely insensible without the other vital functions becoming gravely disturbed. These hysterical anaesthesias can be made to disappear more or less completely by various odd processes. It has been recently found that magnets, plates of metal, or the electrodes of a battery, placed against the skin, have this peculiar power. And when one side is relieved in this way. the anaesthesia is often found to have transferred itself to the opposite side, which until then was well. Whether these strange effects of magnets and metals be due to their direct physiological action, or to a prior effect on the patient's mind (' expectant attention' or * suggestion') is still a mooted question. A still better awakener of sensibility is the hypnotic trance, into which many of these patients can be very easily placed, and in which their lost sensibility not infrequently becomes entirely restored. Such returns of sensibility succeed the times of insensibility and alternate with them. But Messrs. Pierre Janet* and A. Biuet t have shown that during the times of anaesthesia, and coexisting with it, sensibility to the anesthetic parts is also there, in the form of a secondary consciousness entirely cut off from the primary or normal one, but susceptible of being tapped and made to testify to its existence in various odd ways.

Chief amongst these is what M. Janet calls ' the method of distraction.' These hysterics are apt to possess a very narrow field of attention, and to be unable to think of more than one thing at a time. When talking with any person they forget everything else. " When Lucie talked directly with any one," saysM. Janet, "she ceased to be able to hear any other person. You may stand behind her, call her by name, shout abuse into her ears, without making her turn round ; or place yourself before her, show her objects, touch her, etc., without attracting her notice. When finally she becomes aware of you, she thinks you have just come into the room again, and greets you accordingly. This singular forgetfulness makes her liable to tell all her secrete aloud, unrestrained by the presence of unsuitable auditors."

* L'Automatisme Psychologique, Paris, 1889, passim. f See his articles in the Chicago Open Court, for July, August and November, 1889. Also in the Revue Philosophique for 1889 and '90. Now M. Janet found in several subjects like this that if he came up behind them whilst they were plunged in conversa tion with a third party, and addressed them in a whisper, tell ing them to raise their hand or perform other simple acts, they would obey the order given, although their talk ing intelligence was quite unconscious of receiving it. Lead ing them from one thing to another, he made them reply by signs to his whispered questions, and finally made them answer in writing, if a pencil were placed in their hand. The primary consciousness meanwhile went on with the conversation, entirely unaware of these performances on the hand's part. The consciousness which presided over these latter appeared in its turn to be quite as little disturbed by the upper consciousness's concerns. This proof by 'auto matic ' ivriting, of a secondary consciousness's existence, is the most cogent and striking one ; but a crowd of other facts prove the same thing. If I run through them rapidly, the reader will probably be convinced.

The apparently anaesthetic hand of these subjects, for one thing, will often adapt itself discriminatingly to what ever object may be put into it. With a pencil it will make writing movements ; into a pair of scissors it will put its fin gers and will open and shut them, etc., etc. The primary con sciousness, so to call it, is meanwhile unable to say whether or no anything is in the hand, if the latter be hidden from sight. " I put a pair of eyeglasses into Leonie's anaesthetic hand, this hand opens it and raises it towards the nose, but half way thither it enters the field of vision of Leonie, who sees it and stops stupefied : ' Why,' says she, ' I have an eye glass in my left hand !'" M. Binet found a very curious sort of connection between the apparently anaesthetic skin and the mind in some Salpetriere-subjects. Things placed in the hand were not felt, but thought of (apparently in visual terms) and in no wise referred by the subject to their start ing point in the hand's sensation. A key, a knife, placed in the hand occasioned ideas of a key or a knife, but the hand felt nothing. Similarly the subject thought of the number 3, 6, etc., if the hand or finger was bent three or six times by the operator, or if he stroked it three, six, etc., times.

phenomenon, which reminds one of that curious idiosyncrasy of ' colored hearing ' of which a few cases have been lately described with great care by foreign writers. These indi viduals, namely, saw the impression received by the hand, but could not feel it ; and the thing seen appeared by no means associated with the hand, but more like an indepen dent vision, which usually interested and surprised the patient. Her hand being hidden by a screen, she was ordered to look at another screen and to tell of any visual image which might project itself thereon. Numbers would then come, corresponding to the number of times the in sensible member was raised, touched, etc. Colored lines and figures would come, corresponding to similar ones traced on the palm ; the hand itself or its fingers would come when manipulated ; and finally objects placed in it would come ; but on the hand itself nothing would ever be felt. Of course simulation would not be hard here; but M. Binet disbelieves this (usually very shallow) explanation to be a probable one in cases in question.*

The usual way in which doctors measure the delicacy of our touch is by the compass-points. Two points are normally felt as one whenever they are too close together for discrimination ; but what is ' too close ' on one part of the skin may seem very far apart on another. In the middle of the back or on the thigh, less than 3 inches may be too close ; on the finger-tip a tenth of an inch is far enough apart. Now, as tested in this way, with the appeal made to the primary consciousness, which talks through the mouth and seems to hold the field alone, a certain per son's skin may be entirely anaesthetic and not feel the com pass-points at all ; and yet this same skin will prove to have a perfectly normal sensibility if the appeal be made to that other secondary or sub-consciousness, which expresses itself automatically by writing or by movements of the hand. M. Binet, M. Pierre Janet, and M. Jules Janet have all found this. The subject, whenever touched, wonld signify 'one

* This whole phenomenon shows how an idea which remains itself below the threshold of a certain conscious self may occasion associative effects therein. The skin-seusations uufelt by the patient's primary consciousness awaken nevertheless their usual visual associates therein. point ' or ' two points/ as accurately as if she were a nor< mal person. She would signify it only by these movements ; and of the movements themselves her primary self would be as unconscious as of the facts they signified, for what the submerged consciousness makes the hand do automatically is unknown to the consciousness which uses the mouth.

Messrs. Bernheim and Pitres have also proved, by ob servations too complicated to be given in this spot, that the hysterical blindness is no real blindness at all. The eye of an hysteric which is totally blind when the other or seeing eye is shut, will do its share of vision per fectly well when both eyes are open together. But even where both eyes are semi-blind from hysterical disease, the method of automatic writing proves that their percep tions exist, only cut off from communication with the upper consciousness. M. Binet has found the hand of his patients unconsciously writing down words which their eyes were vainly endeavoring to ' see,' i.e., to bring to the upper con sciousness. Their submerged consciousness was of course seeing them, or the hand could not have written as it did. Colors are similarly perceived by the sub-conscious self, which the hysterically color-blind eyes cannot bring to the normal consciousness. Pricks, burns, and pinches on the anaesthetic skin, all unnoticed by the upper self, are recol lected to have been suffered, and complained of, as soon as the under self gets a chance to express itself by the passage of the subject into hypnotic trance.

It must be admitted, therefore, that in certain persons, at least, the total possible consciousness may be split into parts which coexist but mutually ignore each other, and share the objects of knowledge between them. More re markable still, they are complementary. Give an object to one of the consciousnesses, and by that fact you remove it from the other or others. Barring a certain common fund of information, like the command of language, etc., what the upper self knows the under self is ignorant of, and vice versa. M. Janet has proved this beautifully in his subject Lucie. The following experiment will serve as the type of the rest : In her trance he covered her lap with cards, each bearing a number. He then told her that OD