The Principles of Psychology, Vols. 1-2

' ' My mind was in an exceedingly impressionable state. Any place thought of or suggested appeared with all the distinctness of the reality. I thought of the Giant's Causeway in Staffa, and instantly I stood within the portals of Fingal's Cave. Great basaltic columns rose on all sides, while huge waves rolled through the chasm and broke in silence upon the rocky shore. Suddenly there was a roar and blast of sound, and the word ' Ishmaral ' was echoing up the cave. At the enunciation of this remarkable word the great columns of basalt changed into whirling clothes pins and I laughed aloud at the absurdity.

" (I may here state that the word ' Ishmaral' seemed to haunt my other hallucinations, for I remember that I heard it frequently thereafter.) I next enjoyed a sort of metempsychosis. Any animal or thing that I thought of could be made the being which held my mind. I thought of a fox, and instantly I was transformed into that animal. 1 oould distinctly feel myself a fox, could see my long ears and bushy tail, and by a sort of introvision felt that my complete anatomy was that of a fox. Suddenly the point of vision changed. My eyes seemed to be located at the back of my mouth ; I looked out between the parted lips, saw the two rows of pointed teeth, and, closing my mouth with a snap, saw — nothing.

" I was next transformed into a bombshell, felt my size, weight, and thickness, and experienced the sensation of being shot up out of a giant mortar, looking down upon the earth, bursting and falling back in a shower of iron fragments. " Into countless other objects was I transformed, many of them so absurd that I am unable to conceive what suggested them. For example, I was a little china doll, deep down in a bottle of olive oil, next moment a stick of twisted candy, then a skeleton inclosed in a whirling coffin, and so on ad infinitum.

" Towards the end of the delirium the whirling images appeared again, and I was haunted by a singular creation of the brain, which reappeared every few moments. It was an image of a double-faced doll, with a cylindrical body running down to a point like a peg-top. " It was always the same, having a sort of crown on its head, and painted in two colors, green and brown, on a background of blue. The expression of the Janus-like profiles was always the same, as were the adornments of the body. After recovering from the effects of the drug I could not picture to myself exactly how this singular monstrosity appeared, but in subsequent experiences I was always visited by this phantom, and always recognized every detail of its composition. It was like visiting some long-forgotten spot and seeing some sight that had faded from the memory, but which appeared perfectly familiar as soon as looked upon.

" The effects of the drug lasted about an hour and a half, leaving me a trifle tipsy and dizzy ; but after a ten-hour sleep I was myself again, save for a slight inability to keep my mind fixed on any piece of work for any length of time, which remained with me during most of the next day.'' Examples of these singular perversions of perception might be multiplied indefinitely, but I have no more space. Let us turn to the question of what the physiological process may be to which they are due. It must, of course, consist of an excitement from within of those centres which are active in normal perception, identical in kind and degree with that which real external objects are usually needed to induce. The particular process which cur-

rents from the sense-organs arouse would seem under normal circumstances to be arousable in no other way. On p. 72 if. above, we saw that the centres aroused by incoming peripheral currents are probably identical with the centres used in mere imagination ; and that the vividness of the sensational kind of consciousness is probably correlated with a discrete degree of intensity in the process therein aroused. Referring the reader back to that passage and to what was more lately said on p. 103 ff., I now proceed to complete my theory of the perceptive process by an analysis of what may most probably be believed to take place in hallucination strictly so called.

We have seen (p. 75) that the free discharge of cells into each other through associative paths is a likely reason why the maximum intensity of function is not reached when the cells are excited by their neighbors in the cortex. At the end of Chapter XXV we shall return to this conception, and whilst making it still more precise, use it for explaining certain phenomena connected with the will. The idea is that the leakage forward along these paths is too rapid for the inner tension in any centre to accumulate to the maximal explosion-point, unless the exciting currents are greater than those which the various portions of the cortex supply to each other. Currents from the periphery are (as it seems) the only currents whose energy can vanquish the supra-ideational resistance (so to call it) of the cells, and cause the peculiarly intense sort of disintegration with which the sensational quality is linked. If, however , the leakage forward were to stop, the tension inside certain cells might reach the explosion-point, even though the influence which excited them came only from neighboring cortical parts. Let an empty pail with a leak in its bottom, tipped up against a support so that if it ever became full of water it would upset, represent the resting condition of the centre for a certain sort of feeling. Let water poured into it stand for the currents which are its natural stimulus ; then the hole in its bottom will, of course, represent the * paths * by which it transmits its excitement to other associated cells. Now let two other vessels have the functior

of supplying it with water. One of these vessels stands for the neighboring cortical cells, and can pour in hardly any more water than goes out by the leak. The pail consesequently never upsets in consequence of the supply from this source. A current of water passes through it and does work elsewhere, but in the pail itself nothing but what stands for ideatioiial activity is aroused. The other vessel, however, stands for the peripheral sense-organs, and supplies a stream of water so copious that the pail promptly fills up in spite of the leak, and presently upsets ; in other words, sensational activity is aroused. But it is obvious that if the leak were plugged, the slower stream of supply would also end by upsetting the pail.

To apply this to the brain and to thought, if we take a series of processes ABODE, associated together in that order, and suppose that the current through them is very fluent, there will be little intensity anywhere until, perhaps, a pause occurs at E. But the moment the current is blocked anywhere, say between C and D, the process in C must grow more intense, and might even be conceived to explode so as to produce a sensation in the mind instead of an idea.

It would seem that some hallucinations are best to be explained in this way. We have in fact a regular series of facts which can all be formulated under the single law that ^Ae substantive strength of a state of consciousness hears an inverse 'proportion to its suggestiveness. It is the halting-places of our thought which are occupied with distinct imagery. Most of the words we utter have no time to awaken images at all ; they simply awaken the following words. But when the sentence stops, an image dwells for awhile before the mental eye (see Vol. I. p. 243). Again, whenever the associative processes are reduced and impeded by the approach of unconsciousness, as in falling asleep, or growing faint, or becoming narcotized, we find a concomitant increase in the intensity of whatever partial consciousness may survive. In some people what M. Maury has called * hypnagogic ' hallucinations * are the regular concomitant of the process of

falling asleep. Trains of faces, landscapes, etc., pass before the mental eye, first as fancies, then as pseudo-hallucinations, finally as full-fledged hallucinations forming dreams. If we regard association-paths as paths of drainage, then the shutting off of one after another of them as the encroaching cerebral paralysis advances ought to act like the plugging ol the hole in the bottom of the pail, and make the activity more intense in those systems of cells that retain any activity at all. The level rises because the currents are not drained away, until at last the full sensational explosion may occur.

The usual explanation of hypnagogic hallucinations is that they are ideas deprived of their ordinary reductives. In somnolescence, sensations being extinct, the mind, it is said, then having no stronger things to compare its ideas with, ascribes to these the fulness of reality. At ordinary times the objects of our imagination are reduced to the status of subjective facts by the ever-present contrast of our sensations with them. Eliminate the sensations, however, this view supposes, and the * images ' are forthwith * projected ' into the outer world and appear as realities. Thus is the illusion of dreams also explained. This, indeed, after a fashion gives an account of the facts.* And yet it certainly fails to explain the extraordinary vivacity and completeness of so many of our dream-fantasms. The process of ' imagining ' must (in these cases at least f ) be not merely relatively, but absolutely and in itself more intense than at other times. The fact is, it is not a process of imagining, but a genuine sensational process ; and the theory in question is therefore false ^s far as that point is concerned.

Dr. Hughlinecs Jackson's explanation of the epileptic seizure is acknowledged to be masterly. It involves * This theory of incomplete rectification of the inner images by their usual reductives is most brilliantly stated by M. Taine in his work on Intelligence, book ii. chap. i. f Not, of course, in all cases, because the cells remaining active are themselves on the way to be overpowered by the general (unknown) condition to which sleep is due.

principles exactly like those which I am bringing forward here. The * loss of consciousness ' in epilepsy is due to the most highly organized brain-processes being exhausted and thrown out of gear. The less organized (more instinctive) processes, ordinarily inhibited by the others, are then exalted, so that we get as a mere consequence of relief from the inhibition, the meaningless or maniacal action which so often follows the attack. "^ Similarly the sybsuitus tendinorum or jerking of the muscles which so often startles us when we are on the point

* For a full account of Jackson's theories, see his ' Croonian Lectures ' published in the Brit. Med. Journ. for 1884. Cf. also his remarks in the Discussion of Dr. Mercier's paper on Inhibition in ' Brain,' xi. 361. The loss of vivacity in the images in the process of waking, as well as the gain of it in falling asleep, are both well described by M. Taine, who writes (on Intelligence, t. 50, 58) that often in the daytime, when fatigued and seated in a chair, it is sufficient for him to close one eye with a handkerchief, when, " by degrees, the sight of the other eye becomes vague, and it closes. All external sensations are gradually effaced, or cease, at all events, to be remarked ; the internal images, on the other hand, feeble and rapid during the state of complete wakefulness, become intense, distinct, colored, steady, and lasting : there is a sort of ecstasy, accompanied by a feeling of expansion and of comfort. Warned by frequent experience, I know that sleep is coming on, and that I must not disturb the rising vision ; I remain passive, and in a few minutes it is complete. Architecture, landscapes, moving figures, pass slowly by, and sometimes remain, with incomparable clearness of form and fulness of being ; sleep comes on, and I know no more of the real world I am in. Many times, like M. Maury, I have caused myself to be gently roused at different moments of this state, and have thus been able to mark its characters. — The intense image which seems an external object is but a more forcible continuation of the feeble image which an instant before I recognized as internal ; some scrap of a forest, some house, some person which I vaguely imagined on closing my eyes, has in a minute become present to me with full bodily details, so as to change into a complete hallucination. Then, waking up on a hand touching me, I feel the figure decay, lose color, and evaporate ; what had appeared a substance is reduced to a shadow. ...

In such a case, I have often seen, for a passing moment, the image grow pale, waste away, and evaporate ; sometimes, on opening the eyes, a fragment of landscape or the skirt of a dress appears still to float over the fire-irons or on the black hearth." This persistence of dream-objects for a few moments after the eyes are opened seems to be no extremely rare experience. Many cases of it have been reported to me directly. Compare Mtiller's Physiology, Baly's tr., p 945.

of failing asleep, may be interpreted as due to tlie rise (in certain lower motor centres) of the ordinary * tonic * tension to the explosion-point, when the inhibition commonly exerted by the higher centres falls too suddenly away. One possible condition of hallucination then stands revealed, whatever other conditions there may be. When the normal paths of association between a centre and other centres are throivn out of gear^ any axitivity which may exist in the first centre tends to increase in intensity until finally the point may he reached at which the last inward resistance is overcome, and the full sensational process explodes."^ Thus it will happen that causes of an amount of activity in brain-cells which would ordinarily result in a weak consciousness may produce a very strong consciousness when the overflow of these cells is stopped by the torpor of the rest of the brain. A slight peripheral irritation, then, if it reaches the centres of consciousness at all during sleep, will give rise to the dream of a violent sensation. All the books about dreaming are full of anecdotes which illustrate this. For example, M. Maury's nose and lips are tickled with a feather while he sleeps. He dreams he is being tortured by having a pitchplaster applied to his face, torn off, lacerating the skin of nose and lips. Descartes, on being bitten by a flea, dreams of being run through by a sword. A friend tells me, as I write this, of his hair changing its position in his forehead just as he * dozed off ' in his chair a few days since. In- stantly he dreamed that some one had struck him a blow. Examples can be quoted ad libitum, but these are enough, f

* I say the * normal ' paths, because hallucinations are not incompatible with some paths of association being left. Some hypnotic patients will not only have hallucinations of objects suggested to them, but will amplify them and act out the situation. But the paths here seem excessively narrow, and the reflections which ought to make the hallucination incredible do not occur to the subject's mind. In general, the narrower a train of ' ideas ' is, the vivider the consciousness is of each. Under ordinary circumstances, the entire brain probably plays a part in draining any centre which may be ideationally active. When the drainage is reduced in any way it probably makes the active process more intense.

We seem herewith to have an explanation for a certain number of hallucinations. Whenever the normal forward irradiation of intra-cortical excitement through association-paths is checked^ any accidental spontaneous activity or any peripheral stimulation {however inadequate at other times) by which a braincentre may be visited, sets up a process of full sensational intensity therein. In the hallucinations artificially produced in hypnotic subjects, some degree of peripheral excitement seems usually to be required. The brain is asleep as far as its own spontaneous thinking goes, and the words of the * magnetizer ' then awaken a cortical process which drafts off into itself any currents of a related sort which may come in from the periphery, resulting in a vivid objective perception of the suggested thing. Thus, point to a dot on a sheet of paper, and call it * General Grant's photograph,* and your subject will see a photograph of the General there instead of the dot. The dot gives objectivity to the appearance, and the suggested notion of the General gives it form. Then magnify the dot by a lens ; double it by a prism or by nudging the eyeball ; reflect it in a mirror ; turn it upside down ; or wipe it out ; and the subject will tell you that the * photograph ' has been enlarged, doubled, reflected, turned about, or made to disappear. In M. Binet's language, * the dot is the outward point de repere which is needed to give objectivity to your suggestion, and without which the latter will only produce a conception in the subject's mind.t M. Binet has shown that such a periphe-

* M. Bluet's highly important experiments, which were first published in vol. XVII of the Revue Philosophique (1884), are also given in full in chapter ix of his and Fere's work on * Animal Magnetism ' in the International Scientific Series. Where there is no dot on the paper, nor any other visible mark, the subject's judgment about the * portrait ' would seem to be guided by what he sees happening to the entire sheet. f It is a difiicult thing to distinguish in a hypnotic patient between a genuine sensorial hallucination of something suggested and a conception of it merely, coupled with belief that it is there. I have been surprised at the vagueness with which such subjects will often trace upon blank paper the outlines of the pictures which they say they ' see ' thereupon. On the othei

ral poiint de repere is used in an enormous number, not only of hypnotic hallucinations, but of hallucinations of the insane. These latter are often unilateral ; that is, the patient hears the voices always on one side of him, or sees the figure only when a certain one of his eyes is open. In many of these cases it has been distinctly proved that a morbid irritation in the internal ear, or an opacity in the humors of the eye, was the starting point of the current which the patient's diseased acoustic or optical centres clothed with their peculiar products in the way of ideas. Hallucinations produced in this way are 'illusions '; and M, Binefs theory, that all hallucinations must start in the periphery , may be called an attempt to reduce hallucination and illusion to one physiological type, the type, namely, to which normal perception belongs. In every case, according to M. Binet, whether of perception, of hallucination, or of illusion, we get the sensational vividness by means of a current from the peripheral nerves. It may be a mere trace of a current. But that trace is enough to kindle the maximal or supra-ideational process so that the object perceived will have the character of externality. What the nature of the object shall be will depend wholly on the particular system of paths in which the process is kindled. Part of the thing in all cases comes from the sense-organ, the rest is furnished by the mind. But we cannot by introspection distinguish between these parts ; and our only formula for the result is that the brain has reacted on the impression in the normal way. Just so in the dreams which we have considered, and in the hallucinations of which M. Binet tells, we can only say that the brain has reacted in an abnormal way.

M. Bincfs theory accounts indeed for a multitude of cases^ but certainly not for all. The prism does not always double liand, you will hear them say that they find no difference between a real flower which you show them and an imaginary flower which you tell them is beside it. When told that one is imaginary and that they must pick out the real one, they sometimes say the choice is impossible, and •ometimes they point to the imaginary flower. the false appearance,*" nor does the latter always disappeai when the eyes are closed. Dr. Hack Tuke f gives several examples in sane people of well-exteriorized hallucinations which did not respond to Binet's tests ; and Mr. Edmund Gurney X gives a number of reasons why intensity in a cortical process may be expected to result from local pathological activity just as much as its peculiar nature does. For Binet, an abnormally or exclusively active part of the cortex gives the nature of what shall appear, whilst a peripheral sense-organ alone can give the intensity sufficient to make it appear projected into real space. But since this intensity is after all but a matter of degree, one does not see why, under rare conditions, the degree in question might not be attained by inner causes exclusively. In that case we should have certain hallucinations centrally initiated alongside of the peripherally initiated hallucinations, which are the only sort that M. Binet's theory allows. It seems probable on the whole, therefore, that centrally initiated hallucinations can exist. How often they do exist is another question. The existence of hallucinations which affect more than one sense is an argument for central initiation. For grant that the thing seen ma-y have its starting point in the outer world, the voice which it is heard to utter must be due to an influence from the visual region, i.e. must be of central origin.

Sporadic cases of hallucination, visiting people only once in a lifetime (which seem to be by far the most frequenttype), are on any theory hard to understand in detail They are often extraordinarily complete ; and the fact that many of them are reported as veridical, that is, as coinciding with real events, such as accidents, deaths, etc. , of the persons seen, is an additional complication of the phenomenon. The first really scientific study of hallucinatioD

* Only the other day, in three hypnotized girls, I failed to double as hallucination with a prism. Of course it may not have been a fullydeveloped hallucination. iu all its possible bearings, on the basis of a large mass of empirical material, was begun by Mr. Edmund Gurney and is continued by other members of the Society for Psychical Research ; and the * Census ' is now being applied to several countries under the auspices of the International Congress of Experimental Psychology. It is to be hoped that out of these combined labors something solid will eventually grow. The facts shade off into the phenomena of motor automatism, trance, etc.; and nothing but a wide comparative study can give really instructive results.^

The part played by the peripheral sense-organ in hallucination is just as obscure as we found it in the case of imagination. The things seen often seem opaque and hide the background upon which they are projected. It does not follow from this, however, that the retina is actually involved in the vision. A contrary process going on in the visual centres would prevent the retinal impression made by the outer realities from being felt, and this would in mental terms be equivalent to the hiding of them by the imaginary figure. The negative after-images of mental pictures reported by Meyer and Fere, and the negative afterimages of hypnotic hallucinations reported by Binet and others so far constitute the only evidence there is for the retina being involved. But until these after-images are explained in some other way we must admit the possibility of a centrifugal current from the optical centres downwards into the peripheral organ of sight, paradoxical as the course of such a current may appear.

The time which the perceptive process occupies has been inquired into by various experimenters. Some call it perception-time, some choice-time, some di^scrimination-tima The results have been already given in Chapter XIII (vol I, p. 623 ff.), to which the reader is consequently inferred. * In Mr. Curacy's work, just cited, a very large Qumber ot veridic&i caaes are critically discussed. Dr. Komanes gives an interesting variation of these tirae-ineasiirements. He found *

" an astonishing difference between different individuals with respect to the rate at which they are able to read. Of course reading implies enormously intricate processes of perception both of the sensuous and of the intellectual order ; but if we choose for these observations persons who have been accustomed to read much, we may consider that they are all very much on a par with respect to the amount of practice which they have had, so that the differences in their rates of reading may fairly be attributed to real differences in their rates of forming complex perceptions in rapid succession, and not to any merely accidental differences arising from greater or less facility acquired by «pecial practice.

*' My experiments consisted in marking a brief printed paragraphia a book which had never been read by any of the persons to whom it was to be presented. The paragraph, which contained simple statements of simple facts, was marked on the margin with pencil. The book was then placed before the reader open, the page, however, being covered with a sheet of paper. Having pointed out to the reader upon this sheet of paper what part of the underlying page the marked paragraph occupied, I suddenly removed the sheet of paper with one hand, while I started a chronograph with the other. Twenty seconds being allowed for reading the paragraph (ten lines octavo), as soon as the time was up I again suddenly placed the sheet of paper over the printed page, passed the book on to the next reader, and repeated the experiment as before. Meanwhile, the first reader, the moment after the book had been removed, wrote down all that he or she could remember having read. And so on with all the other readers.

"Now the results of a number of experiments conducted on this method were to show, as I have said, astonishing differences in the maximum rate of reading which is possible to different individuals, all of whom have been accustomed to extensive reading. That is to say, the difference may amount to 4 to 1 ; or, otherwise stated, in a given time one individual may be able to read four times as much as another. Moreover, it appeared that there was no relationship between slowness of reading and power of assimilation ; on the contrary, when all the efforts are directed to assimilating as much as possible in a given time, the rapid readers (as shown by their written notes) usually give a better account of the portions of the paragraph which have been compassed by the slow readers than the latter are able to give ; and the ntost rapid reader I have found is also the best at assimilating. I should further say that there is no relationship between rapidity of perception as thus tested and intellectual activity as tested by the general results of intellectual work ; for I have tried the experiment with

several highly distinguished men in science and literature, most of whom I found to be slow readers."* * Literature. The best treatment of perception with which I am acquainted is that in Mr. James Sully's book on ' Illusions ' in the International Scientific Series. On hallucinations the literature is large. Gurney, Kandinsky (as already cited), and some articles by Kraepelin in the Vierteljahrschrift ftir Wissenschaftliche Philosophic, vol. v (1881), are the most systematic studies recently made. All works on Insanity treat of them. Dr. W. W. Ireland's works, ' The Blot upon the Brain ' (1886) and * Through the Ivory Gate ' (1890) have much information on the subject. Gurney gives pretty complete references to older literature. The most important thing on the subject from the point of view of theory is the article by Mr. Myers on the Demon of Socrates in the Proceedings of the Society for Psychical Research for 1889, p. 522.