Chapter XXVIII · (continued 2)

But when you give things mathematical and mechanical names and call them just so many solids in just such positions, describing just such paths with just such velocities, all is changed. Your sagacity finds its reward in the verification by nature of all the deductions which you may next proceed to make. Your 'things' realize all the consequences of the names by which you classed them. The modern mechanico-physical philosophy of which we are all so proud, because it includes the nebular cosmogony, the conservation of energy, the kinetic theory of heat and gases, etc., etc., begins by saying that the only facts are collocations and motions of primordial solids, and the only laws the changes of motion which changes in collocation bring. The ideal which this philosophy strives after is a mathematical world-formula, by which, if all the collocations and motions at a given moment were known, it would be possible to reckon those of any wished-for future moment, by simply considering the necessary geometrical, arithmetical, and logical implications. Once we have the world in this bare shape, we can fling our net of a priori relations over all its terms, and pass from one of its phases to another by inward thought-necessity. Of course it is a world with a very minimum of rational stuff. The sentimental facts and relations are butchered at a blow. But the rationality yielded is so superbly complete in form that to many minds this atones for the loss, and reconciles the thinker to the notion of a purposeless universe, in which all the things and qualities men love, dulcissima mundi nomina, are but illusions of our fancy attached to accidental clouds of dust which will be dissipated by the eternal cosmic weather as carelessly as they were formed.

The popular notion that 'Science' is forced on the mind ab extra, and that our interests have nothing to do with its constructions, is utterly absurd. The craving to believe that the things of the world belong to kinds which are related by inward rationality together, is the parent of Science as well as of sentimental philosophy; and the original investigator always preserves a healthy sense of how plastic the materials are in his hands.

"Once for all," says Helmholtz in beginning that little work of his which laid the foundations of the 'conservation of energy,' "it is the task of the physical sciences to seek for laws by which particular processes in nature may be referred to general rules, and deduced from such again. Such rules (for example the laws of reflection or refraction of light, or that of Mariotte and Gay-Lussac for gas-volumes) are evidently nothing but generic-concepts for embracing whole classes of phenomena. The search for them is the business of the experimental division of our Science. Its theoretic division, on the other hand, tries to discover the unknown causes of processes from their visible effects; tries to understand them by the law of causality.... The ultimate goal of theoretic physics is to find the last unchanging causes of the processes in Nature. Whether all processes be really ascribable to such causes, whether, in other words, nature be completely intelligible, or whether there be changes which would elude the law of a necessary causality, and fall into a realm of spontaneity or freedom, is not here the place to determine; but at any rate it is clear that the Science whose aim it is to make nature appear intelligible [die Natur zu begreifen] must start with the assumption of her intelligibility, and draw consequences in conformity with this assumption, until irrefutable facts show the limitations of this method.... The postulate that natural phenomena must be reduced to changeless ultimate causes next shapes itself so that forces unchanged by time must be found to be these causes. Now in Science we have already found portions of matter with changeless forces (indestructible qualities), and called them (chemical) elements. If, then, we imagine the world composed of elements with inalterable qualities, the only changes that can remain possible in such a world are spatial changes, i.e. movements, and the only outer relations which can modify the action of the forces are spatial too, or, in other words, the forces are motor forces dependent for their effect only on spatial relations. More exactly still: The phenomena of nature must be reduced to [zurückgeführt, conceived as, classed as] motions of material points with inalterable motor forces acting according to space-relations alone.... But points have no mutual space-relations except their distance,... and a motor force which they exert upon each other can cause nothing but a change of distance—i.e. be an attractive or a repulsive force.... And its intensity can only depend on distance. So that at last the task of Physics resolves itself into this, to refer phenomena to inalterable attractive and repulsive forces whose intensity varies with distance. The solution of this task would at the same time be the condition of Nature's complete intelligibility."[553]

The subjective interest leading to the assumption could not be more candidly expressed. What makes the assumption 'scientific' and not merely poetic, what makes a Helmholtz and his kin discoverers, is that the things of Nature turn out to act as if they were of the kind assumed. They behave as such mere drawing and driving atoms would behave; and so far as they have been distinctly enough translated into molecular terms to test the point, so far a certain fantastically ideal object, namely, the mathematical sum containing their mutual distances and velocities, is found to be constant throughout all their movements. This sum is called the total energy of the molecules considered. Its constancy or 'conservation' gives the name to the hypothesis of molecules and central forces from which it was logically deduced.

Take any other mathematico-mechanical theory and it is the same. They are all translations of sensible experiences into other forms, substitutions of items between which ideal relations of kind, number, form, equality, etc., obtain, for items between which no such relations obtain; coupled with declarations that the experienced form is false and the ideal form true, declarations which are justified by the appearance of new sensible experiences at just those times and places at which we logically infer that their ideal correlates ought to be. Wave-hypotheses thus make us predict rings of darkness and color, distortions, dispersions, changes of pitch in sonorous bodies moving from us, etc.; molecule-hypotheses lead to predictions of vapor-density, freezing point, etc.,—all which predictions fall true.

Thus the world grows more orderly and rational to the mind, which passes from one feature of it to another by deductive necessity, as soon as it conceives it as made up of so few and so simple phenomena as bodies with no properties but number and movement to and fro.

METAPHYSICAL AXIOMS.

But alongside of these ideal relations between terms which the world verifies, there are other ideal relations not as yet so verified. I refer to those propositions (no longer expressing mere results of comparison) which are formulated in such metaphysical and æsthetic axioms as "The Principle of things is one;" "The quantity of existence is unchanged;" "Nature is simple and invariable;" "Nature acts by the shortest ways;" "Ex nihilo nihil fit;" "Nothing can be evolved which was not involved;" "Whatever is in the effect must be in the cause;" "A thing can only work where it is;" "A thing can only affect another of its own kind;" "Cessante causa, cessat et effectus;" "Nature makes no leaps;" "Things belong to discrete and permanent kinds;" "Nothing is or happens without a reason;" "The world is throughout rationally intelligible;" etc., etc., etc. Such principles as these, which might be multiplied to satiety,[554] are properly to be called postulates of rationality, not propositions of fact. If nature did obey them, she would be pro tanto more intelligible; and we seek meanwhile so to conceive her phenomena as to show that she does obey them. To a certain extent we succeed. For example, instead of the 'quantity of existence' so vaguely postulated as unchanged, Nature allows us to suppose that curious sum of distances and velocities which for want of a better term we call 'energy.' For the effect being 'contained in the cause,' nature lets us substitute 'the effect is the cause,' so soon as she lets us conceive both effect and cause as the same molecules, in two successive positions.—But all around these incipient successes (as all around the molecular world, so soon as we add to it as its 'effects' those illusory 'things' of common-sense which we had to butcher for its sake), there still spreads a vast field of irrationalized fact whose items simply are together, and from one to another of which we can pass by no ideally 'rational' way.

It is not that these more metaphysical postulates of rationality are absolutely barren—though barren enough they were when used, as the scholastics used them, as immediate propositions of fact.[555] They have a fertility as ideals, and keep us uneasy and striving always to recast the world of sense until its lines become more congruent with theirs. Take for example the principle that 'nothing can happen without a cause.' We have no definite idea of what we mean by cause, or of what causality consists in. But the principle expresses a demand for some deeper sort of inward connection between phenomena than their merely habitual time-sequence seems to us to be. The word 'cause' is, in short, an altar to an unknown god; an empty pedestal still marking the place of a hoped-for statue. Any really inward belonging-together of the sequent terms, if discovered, would be accepted as what the word cause was meant to stand for. So we seek, and seek; and in the molecular systems we find a sort of inward belonging in the notion of identity of matter with change of collocation. Perhaps by still seeking we may find other sorts of inward belonging, even between the molecules and those 'secondary qualities,' etc., which they produce upon our minds.

It cannot be too often repeated that the triumphant application of any one of our ideal systems of rational relations to the real world justifies our hope that other systems may be found also applicable. Metaphysics should take heart from the example of physics, simply confessing that hers is the longer task. Nature may be remodelled, nay, certainly will be remodelled, far beyond the point at present reached. Just how far?—is a question which only the whole future history of Science and Philosophy can answer.[556] Our task being Psychology, we cannot even cross the threshold of that larger problem.

Besides the mental structure which results in such metaphysical principles as those just considered, there is a mental structure which expresses itself in

ÆSTHETIC AND MORAL PRINCIPLES.

The æsthetic principles are at bottom such axioms as that a note sounds good with its third and fifth, or that potatoes need salt. We are once for all so made that when certain impressions come before our mind, one of them will seem to call for or repel the others as its companions. To a certain extent the principle of habit will explain these æsthetic connections. When a conjunction is repeatedly experienced, the cohesion of its terms grows grateful, or at least their disruption grows unpleasant. But to explain all æsthetic judgments in this way would be absurd; for it is notorious how seldom natural experiences come up to our æsthetic demands. Many of the so-called metaphysical principles are at bottom only expressions of æsthetic feeling. Nature is simple and invariable; makes no leaps, or makes nothing but leaps; is rationally intelligible; neither increases nor diminishes in quantity; flows from one principle, etc., etc.,—what do all such principles express save our sense of how pleasantly our intellect would feel if it had a Nature of that sort to deal with? The subjectivity of which feeling is of course quite compatible with Nature also turning out objectively to be of that sort, later on.

The moral principles which our mental structure engenders are quite as little explicable in toto by habitual experiences having bred inner cohesions. Rightness is not mere usualness, wrongness not mere oddity, however numerous the facts which might be invoked to prove such identity. Nor are the moral judgments those most invariably and emphatically impressed on us by public opinion. The most characteristically and peculiarly moral judgments that a man is ever called on to make are in unprecedented cases and lonely emergencies, where no popular rhetorical maxims can avail, and the hidden oracle alone can speak; and it speaks often in favor of conduct quite unusual, and suicidal as far as gaining popular approbation goes. The forces which conspire to this resultant are subtle harmonies and discords between the elementary ideas which form the data of the case. Some of these harmonies, no doubt, have to do with habit; but in respect to most of them our sensibility must assuredly be a phenomenon of supernumerary order, correlated with a brain-function quite as secondary as that which takes cognizance of the diverse excellence of elaborate musical compositions. No more than the higher musical sensibility can the higher moral sensibility be accounted for by the frequency with which outer relations have cohered.[557] Take judgments of justice or equity, for example. Instinctively, one judges everything differently, according as it pertains to one's self or to some one else. Empirically one notices that everybody else does the same. But little by little there dawns in one the judgment "nothing can be right for me which would not be right for another similarly placed;" or "the fulfilment of my desires is intrinsically no more imperative than that of anyone else's;" or "what it is reasonable that another should do for me, it is also reasonable that I should do for him;"[558] and forthwith the whole mass of the habitual gets overturned. It gets seriously overturned only in a few fanatical heads. But its overturning is due to a back-door and not to a front-door process. Some minds are preternaturally sensitive to logical consistency and inconsistency. When they have ranked a thing under a kind, they must treat it as of that kind's kind, or feel all out of tune. In many respects we do class ourselves with other men, and call them and ourselves by a common name. They agree with us in having the same Heavenly Father, in not being consulted about their birth, in not being themselves to thank or blame for their natural gifts, in having the same desires and pains and pleasures, in short in a host of fundamental relations. Hence, if these things be our essence, we should be substitutable for other men, and they for us, in any proposition in which either of us is involved. The more fundamental and common the essence chosen, and the more simple the reasoning,[559] the more wildly radical and unconditional will the justice be which is aspired to. Life is one long struggle between conclusions based on abstract ways of conceiving cases, and opposite conclusions prompted by our instinctive perception of them as individual facts. The logical stickler for justice always seems pedantic and mechanical to the man who goes by tact and the particular instance, and who usually makes a poor show at argument. Sometimes the abstract conceiver's way is better, sometimes that of the man of instinct. But just as in our study of reasoning we found it impossible to lay down any mark whereby to distinguish right conception of a concrete case from confusion (see pp. 336, 350), so here we can give no general rule for deciding when it is morally useful to treat a concrete case as sui generis, and when to lump it with others in an abstract class.[560]

An adequate treatment of the way in which we come by our æsthetic and moral judgments would require a separate chapter, which I cannot conveniently include in this book. Suffice it that these judgments express inner harmonies and discords between objects of thought; and that whilst outer cohesions frequently repeated will often seem harmonious, all harmonies are not thus engendered, but our feeling of many of them is a secondary and incidental function of the mind. Where harmonies are asserted of the real world, they are obviously mere postulates of rationality, so far as they transcend experience. Such postulates are exemplified by the ethical propositions that the individual and universal good are one, and that happiness and goodness are bound to coalesce in the same subject.

SUMMARY OF WHAT PRECEDES.

I will now sum up our progress so far by a short summary of the most important conclusions which we have reached.

The mind has a native structure in this sense, that certain of its objects, if considered together in certain ways, give definite results; and that no other ways of considering, and no other results, are possible if the same objects be taken.

The results are 'relations' which are all expressed by judgments of subsumption and of comparison.

The judgments of subsumption are themselves subsumed under the laws of logic.

Those of comparison are expressed in classifications, and in the sciences of arithmetic and geometry.

Mr. Spencer's opinion that our consciousness of classificatory, logical, and mathematical relations between ideas is due to the frequency with which the corresponding 'outer relations' have impressed our minds, is unintelligible.

Our consciousness of these relations, no doubt, has a natural genesis. But it is to be sought rather in the inner forces which have made the brain grow, than in any mere paths of 'frequent' association which outer stimuli may have ploughed in that organ.

But let our sense for these relations have arisen as it may, the relations themselves form a fixed system of lines of cleavage, so to speak, in the mind, by which we naturally pass from one object to another; and the objects connected by these lines of cleavage are often not connected by any regular time- and space-associations. We distinguish, therefore, between the empirical order of things, and this their rational order of comparison; and, so far as possible, we seek to translate the former into the latter, as being the more congenial of the two to our intellect.

Any classification of things into kinds (especially if the kinds form series, or if they successively involve each other) is a more rational way of conceiving the things than is that mere juxtaposition or separation of them as individuals in time and space which is the order of their crude perception. Any assimilation of things to terms between which such classificatory relations, with their remote and mediate transactions, obtain, is a way of bringing the things into a more rational scheme.

Solids in motion are such terms; and the mechanical philosophy is only a way of conceiving nature so as to arrange its items along some of the more natural lines of cleavage of our mental structure.

Other natural lines are the moral and æsthetic relations. Philosophy is still seeking to conceive things so that these relations also may seem to obtain between them.

As long as things have not successfully been so conceived, the moral and æsthetic relations obtain only between entia rationis, terms in the mind; and the moral and æsthetic principles remain but postulates, not propositions, with regard to the real world outside.

There is thus a large body of a priori or intuitively necessary truths. As a rule, these are truths of comparison only, and in the first instance they express relations between merely mental terms. Nature, however, acts as if some of her realities were identical with these mental terms. So far as she does this, we can make a priori propositions concerning natural fact. The aim of both science and philosophy is to make the identifiable terms more numerous. So far it has proved easier to identify nature's things with mental terms of the mechanical than with mental terms of the sentimental order.

The widest postulate of rationality is that the world is rationally intelligible throughout, after the pattern of some ideal system. The whole war of the philosophies is over that point of faith. Some say they can see their way already to the rationality; others that it is hopeless in any other but the mechanical way. To some the very fact that there is a world at all seems irrational. Nonentity would be a more natural thing than existence, for these minds. One philosopher at least says that the relatedness of things to each other is irrational anyhow, and that a world of relations can never be made intelligible.[561]

With this I may be assumed to have completed the programme which I announced at the beginning of the chapter, so far as the theoretic part of our organic mental structure goes. It can be due neither to our own nor to our ancestors' experience. I now pass to those practical parts of our organic mental structure. Things are a little different here; and our conclusion, though it lies in the same direction, can be by no means as confidently expressed.

To be as short and simple as possible, I will take the case of instincts, and, supposing the reader to be familiar with Chapter XXIV, I will plunge in medias res.

THE ORIGIN OF INSTINCTS.

Instincts must have been either

1) Each specially created in complete form, or

2) Gradually evolved.

As the first alternative is nowadays obsolete, I proceed directly to the second. The two most prominent suggestions as to the way in which instincts may have been evolved are associated with the names of Lamarck and Darwin.

Lamarck's statement is that animals have wants, and contract, to satisfy them, habits which transform themselves gradually into so many propensities which they can neither resist nor change. These propensities, once acquired, propagate themselves by way of transmission to the young, so that they come to exist in new individuals, anteriorly to all exercise. Thus are the same emotions, the same habits, the same instincts, perpetuated without variation from one generation to another, so long as the outward conditions of existence remain the same.[562] Mr. Lewes calls this the theory of 'lapsed intelligence.' Mr. Spencer's words are clearer than Lamarck's, so that I will quote from him:[563]

"Setting out with the unquestionable assumption, that every new form of emotion making its appearance in the individual or the race is a modification of some pre-existing emotion, or a compounding of several pre-existing emotions, we should be greatly aided by knowing what always are the pre-existing emotions. When, for example, we find that very few, if any, of the lower animals show any love of accumulation, and that this feeling is absent in infancy; when we see that an infant in arms exhibits anger, fear, wonder, while yet it manifests no desire of permanent possession; and that a brute which has no acquisitive emotion can nevertheless feel attachment, jealousy, love of approbation,—we may suspect that the feeling which property satisfies is compounded out of simpler and deeper feelings. We may conclude that as when a dog hides a bone there must exist in him a prospective gratification of hunger, so there must similarly, at first, in all cases where anything is secured or taken possession of, exist an ideal excitement of the feeling which that thing will gratify. We may further conclude that when the intelligence is such that a variety of objects come to be utilized for different purposes; when, as among savages, divers wants are satisfied through the articles appropriated for weapons, shelter, clothing, ornament,—the act of appropriating comes to be one constantly involving agreeable associations, and one which is therefore pleasurable, irrespective of the end subserved. And when, as in civilized life, the property acquired is of a kind not conducing to one order of gratifications, but is capable of ministering to all gratifications, the pleasure of acquiring property grows more distinct from each of the various pleasures subserved—is more completely differentiated into a separate emotion.[564] It is well known that on newly-discovered islands not inhabited by man, birds are so devoid of fear as to allow themselves to be knocked over with sticks, but that in the course of generations they acquire such a dread of man as to fly on his approach, and that this dread is manifested by young as well as old. Now unless this change be ascribed to the killing off of the least fearful, and the preservation and multiplication of the more fearful, which, considering the small number killed by man, is an inadequate cause, it must be ascribed to accumulated experiences, and each experience must be held to have a share in producing it. We must conclude that in each bird that escapes with injuries inflicted by man, or is alarmed by the outcries of other members of the flock,... there is established an association of ideas between the human aspect and the pains, direct and indirect, suffered from human agency. And we must further conclude that the state of consciousness which impels the bird to take flight is at first nothing more than an ideal reproduction of those painful impressions which before followed man's approach; that such ideal reproduction becomes more vivid and more massive as the painful experiences, direct or sympathetic, increase; and that thus the emotion, in its incipient state, is nothing else than an aggregation of the revived pains before experienced. As, in the course of generations, the young birds of this race begin to display a fear of man before they have been injured by him, it is an unavoidable inference that the nervous system of the race has been organically modified by these experiences; we have no choice but to conclude that when a young bird is thus led to fly, it is because the impression produced on its senses by the approaching man entails, through an incipiently reflex action, a partial excitement of all those nerves which, in its ancestors, had been excited under the like conditions; that this partial excitement has its accompanying painful consciousness; and that the vague painful consciousness thus arising constitutes emotion proper—emotion undecomposable into specific experiences, and therefore seemingly homogeneous. If such be the explanation of the fact in this case, then it is in all cases. If the emotion is so generated here, then it is so generated throughout. If so, we must perforce conclude that the emotional modifications displayed by different nations, and those higher emotions by which civilized are distinguished from savage, are to be accounted for on the same principle. And, concluding this, we are led strongly to suspect that the emotions in general have severally thus originated."[565]

Obviously the word 'emotion' here means instinct as well,—the actions we call instinctive are expressions or manifestations of the emotions whose genesis Mr. Spencer describes. Now if habit could thus bear fruit outside the individual life, and if the modifications so painfully acquired by the parents' nervous systems could be found ready-made at birth in those of the young, it would be hard to overestimate the importance, both practical and theoretical, of such an extension of its sway. In principle, instincts would then be assimilated to 'secondarily-automatic' habits, and the origin of many of them out of tentative experiments made during ancestral lives, perfected by repetition, addition, and association through successive generations, would be a comparatively simple thing to understand.

Contemporary students of instinct have accordingly been alert to discover all the facts which would seem to establish the possibility of such an explanation. The list is not very long, considering what a burden of conclusions it has to bear. Let acquisitiveness and fear of man, as just argued for by Spencer, lead it off. Other cases of the latter sort are the increased shyness of the woodcock noticed to have occurred within sixty years' observation by Mr. T. A. Knight, and the greater shyness everywhere shown by large than by small birds, to which Darwin has called attention. Then we may add—

The propensities of 'pointing,' 'retrieving,' etc., in sporting dogs, which seem partly, at any rate, to be due to training, but which in well-bred stock are all but innate. It is in these breeds considered bad for a litter of young if its sire or dam have not been trained in the field.

Docility of domestic breeds of horses and cattle.

Tameness of young of tame rabbit—young wild rabbits being invincibly timid.

Young foxes are most wary in those places where they are most severely hunted.

Wild ducks, hatched out by tame ones, fly off. But if kept close for some generations, the young are said to become tame.[566]

Young savages at a certain age will revert to the woods.

English greyhounds taken to the high plateau of Mexico could not at first run well, on account of rarefied air. Their whelps entirely got over the difficulty.

Mr. Lewes somewhere[567] tells of a terrier pup whose parents had been taught to 'beg,' and who constantly threw himself spontaneously into the begging attitude. Darwin tells of a French orphan-child, brought up out of France, yet shrugging like his ancestors.[568]

Musical ability often increases from generation to generation in the families of musicians.

The hereditarily epileptic guinea-pigs of Brown-Séquard, whose parents had become epileptic through surgical operations on the spinal cord or sciatic nerve. The adults often lose some of their hind toes, and the young, in addition to being epileptic, are frequently born with the corresponding toes lacking. The offspring of guinea-pigs whose cervical sympathetic nerve has been cut on one side will have the ear larger, the eyeball smaller, etc., just like their parents after the operation. Puncture of the 'restiform body' of the medulla will, in the same animal, congest and enlarge one eye, and cause gangrene of one ear. In the young of such parents the same symptoms occur.

Physical refinement, delicate hands and feet, etc., appear in families well-bred and rich for several generations.

The 'nervous' temperament also develops in the descendants of sedentary brain-working people.

Inebriates produce offspring in various ways degenerate.

Nearsightedness is produced by indoor occupation for generations. It has been found in Europe much more frequent among schoolchildren in towns than among children of the same age in the country.

These latter cases are of the inheritance of structural rather than of functional peculiarities. But as structure gives rise to function it may be said that the principle is the same. Amongst other inheritances of adaptive[569] structural change may be mentioned:

The 'Yankee' type.

Scrofula, rickets, and other diseases of bad conditions of life.

The udders and permanent milk of the domestic breeds of cow.

The 'fancy' rabbit's ears, drooping through lack of need to erect them. Dog's, ass's, etc., in some breeds ditto.

The obsolete eyes of mole and various cave-dwelling animals.

The diminished size of the wing-bones of domesticated ducks, due to ancestral disuse of flight.[570]

These are about all the facts which, by one author or another, have been invoked as evidence in favor of the 'lapsed intelligence' theory of the origin of instincts.

Mr. Darwin's theory is that of the natural selection of accidentally produced tendencies to action.

"It would," says he, "be the most serious error to suppose that the greater number of instincts have been acquired by habit in one generation, and then transmitted by inheritance in succeeding generations. It can clearly be shown that the most wonderful instincts with which we are acquainted, namely, those of the hive-bee and of many ants, could not possibly have been thus acquired.[571] It will be universally admitted that instincts are as important as corporeal structure for the welfare of each species, under its present conditions of life. Under changed conditions of life, it is at least possible that slight modifications of instinct might be profitable to a species; and if it can be shown that instincts do vary ever so little, then I can see no difficulty in natural selection preserving and continually accumulating variations of instinct to any extent that may be profitable. It is thus, as I believe, that all the most complex and wonderful instincts have arisen.... I believe that the effects of habit are of quite subordinate importance to the effects of the natural selection of what may be called accidental variations of instincts;—that is, of variations produced by the same unknown causes which produce slight deviations of bodily structure."[572]

The evidence for Mr. Darwin's view is too complex to be given in this place. To my own mind it is quite convincing. If, with the Darwinian theory in mind, one re-reads the list of examples given in favor of the Lamarckian theory, one finds that many of the cases are irrelevant, and that some make for one side as well as for the other. This is so obvious in many of the cases that it is needless to point it out in detail. The shrugging child and the begging pup, e.g., prove somewhat too much. They are examples so unique as to suggest spontaneous variation rather than inherited habit. In other cases the observations much need corroboration, e.g., the effects of not training for a generation in sporting dogs and race-horses, the difference between young wild rabbits born in captivity and young tame ones, the cumulative effect of many generations of captivity on wild ducks, etc.

Similarly, the increased wariness of the large birds, of those on islands frequented by men, of the woodcock, of the foxes, may be due to the fact that the bolder families have been killed off, and left none but the naturally timid behind, or simply to the individual experience of older birds being imparted by example to the young so that a new educational tradition has occurred.—The cases of physical refinement, nervous temperament, Yankee type, etc., also need much more discriminating treatment than they have yet received from the Lamarckians. There is no real evidence that physical refinement and nervosity tend to accumulate from generation to generation in aristocratic or intellectual families; nor is there any that the change in that direction which Europeans transplanted to America undergo is not all completed in the first generation of children bred on our soil. To my mind, the facts all point that way. Similarly the better breathing of the greyhounds born in Mexico was surely due to a post-natal adaptation of the pups' thorax to the rarer air.

Distinct neurotic degeneration may undoubtedly accumulate from parent to child, and as the parent usually in this case grows worse by his own irregular habits of life, the temptation lies near to ascribe the child's deterioration to this cause. This, again, is a hasty conclusion. For neurotic degeneration is unquestionably a disease whose original causes are unknown; and like other 'accidental variations' it is hereditary. But it ultimately ends in sterility; and it seems to me quite unfair to draw any conclusions from its natural history in favor of the transmission of acquired peculiarities. Nor does the degeneration of the children of alcoholics prove anything in favor of their having inherited the shattered nervous system which the alcohol has induced in their parents: because the poison usually has a chance to directly affect their own bodies before birth, by acting on the germinal matter from which they are formed whilst it is still nourished by the alcoholized blood of the parent. In many cases, moreover, the parental alcoholics are themselves degenerates neurotically, and the drink-habit is only a symptom of their disease, which in some form or other they also propagate to their children.

There remain the inherited mutilations of the guinea-pig. But these are such startling exceptions to the ordinary rule with animals that they should hardly be used as examples of a typical process. The docility of domestic cattle is certainly in part due to man's selection, etc., etc. In a word, the proofs form rather a beggarly array.

Add to this that the writers who have tried to carry out the theory of transmitted habit with any detail are always obliged somewhere to admit inexplicable variation. Thus Spencer allows that

"Sociality can begin only where, through some slight variation, there is less tendency than usual for the individuals to disperse.... That slight variations of mental nature, sufficient to initiate this process, may be fairly assumed, all our domestic animals show us: differences in their characters and likings are conspicuous. Sociality having thus commenced, and survival of the fittest tending ever to maintain and increase it, it will be further strengthened by the inherited effects of habit."[573] Again, in writing of the pleasure of pity, Mr. Spencer says: "This feeling is not one that has arisen through the inherited effects of experiences, but belongs to a quite different group, traceable to the survival of the fittest simply—to the natural selection of incidental variations. In this group are included all the bodily appetites, together with those simpler instincts, sexual and parental, by which every race is maintained; and which must exist before the higher processes of mental evolution can commence."[574]

The inheritance of tricks of manner and trifling peculiarities, such as handwriting, certain odd gestures when pleased, peculiar movements during sleep, etc., have also been quoted in favor of the theory of transmission of acquired habits. Strangely enough; for of all things in the world these tricks seem most like idiosyncratic variations. They are usually defects or oddities which the education of the individual, the pressure of what is really acquired by him, would counteract, but which are too native to be repressed, and breaks through all artificial barriers, in his children as well as in himself.

I leave my text practically just as it was written in 1885. I proceeded at that time to draw a tentative conclusion to the effect that the origin of most of our instincts must certainly be deemed fruits of the back-door method of genesis, and not of ancestral experience in the proper meaning of the term. Whether acquired ancestral habits played any part at all in their production was still an open question in which it would be as rash to affirm as to deny. Already before that time, however, Professor Weismann of Freiburg had begun a very serious attack upon the Lamarckian theory,[575] and his polemic has at last excited such a widespread interest among naturalists that the whilom almost unhesitatingly accepted theory seems almost on the point of being abandoned.

I will therefore add some of Weismann's criticisms of the supposed evidence to my own. In the first place, he has a captivating theory of descent of his own,[576] which makes him think it a priori impossible that any peculiarity acquired during lifetime by the parent should be transmitted to the germ. Into the nature of that theory this is not the place to go. Suffice to say that it has made him a keener critic of Lamarck's and Spencer's theory than he otherwise might have been. The only way in which the germinal products can be influenced whilst in the body of the parent is, according to Weismann, by good or bad nutrition. Through this they may degenerate in various ways or lose vitality altogether. They may also be infected through the blood by small-pox, syphilis, or other virulent diseases, and otherwise be poisoned. But peculiarities of neural structure and habit in the parents which the parents themselves were not born with, they can never acquire unless perhaps accidentally through some coincidental variation of their own. Accidental variations develop of course into idiosyncrasies which tend to pass to later generations in virtue of the well-known law which no one doubts.

Referring to the often-heard assertion that the increase of talent found in certain families from one generation to another is due to the transmitted effects of exercise of the faculty concerned (the Bachs, the Bernoullis, Mozart, etc.), he sensibly remarks, that the talent being kept in exercise, it ought to have gone on growing for an indefinite number of generations. As a matter of fact, it quickly reaches a maximum, and then we hear no more of it, which is what happens always when an idiosyncrasy is exposed to the effects of miscellaneous intermarriage.

The hereditary epilepsy and other degenerations of the operated guinea-pigs are explained by Professor Weismann as results of infection of the young by the parent's blood. The latter he supposes to undergo a pathologic change in consequence of the original traumatic injury. The obsolescence of disused organs he explains very satisfactorily, without invoking any transmission of the direct effects of disuse, by his theory of panmixy, for which I must refer to his own writings. Finally, he criticises searchingly the stories we occasionally hear of inherited mutilations in animals (dogs' ears and tails, etc.), and cites a prolonged series of experiments of his own on mice, which he bred for many generations, cutting off both parental tails each time, without interfering in the least with the length of tail with which the young continued to be born.

The strongest argument, after all, in favor of the Lamarckian theory remains the a priori one urged by Spencer in his little work (much the solidest thing, by the way, which he has ever written) 'The Factors of Organic Evolution.' Since, says Mr. Spencer, the accidental variations of all parts of the body are independent of each other, if the entire organization of animals were due to such accidental variations alone, the amount of mutual adaptation and harmony that we now find there could hardly possibly have come about in any finite time. We must rather suppose that the divers varying parts brought the other parts into harmony with themselves by exercising them ad hoc, and that the effects of the exercise remained and were passed on to the young. This forms, of course, a great presumption against the all-sufficiency of the view of selection of accidental variations exclusively. But it must be admitted that in favor of the contrary view, that adaptive changes are inherited, we have as yet perhaps not one single unequivocal item of positive proof.

I must therefore end this chapter on the genesis of our mental structure by reaffirming my conviction that the so-called Experience-philosophy has failed to prove its point. No more if we take ancestral experiences into account than if we limit ourselves to those of the individual after birth, can we believe that the couplings of terms within the mind are simple copies of corresponding couplings impressed upon it by the environment. This indeed is true of a small part of our cognitions. But so far as logical and mathematical, ethical, æsthetical, and metaphysical propositions go, such an assertion is not only untrue but altogether unintelligible; for these propositions say nothing about the time- and space-order of things, and it is hard to understand how such shallow and vague accounts of them as Mill's and Spencer's could ever have been given by thinking men.

The causes of our mental structure are doubtless natural, and connected, like all our other peculiarities, with those of our nervous structure. Our interests, our tendencies of attention, our motor impulses, the æsthetic, moral, and theoretic combinations we delight in, the extent of our power of apprehending schemes of relation, just like the elementary relations themselves, time, space, difference and similarity, and the elementary kinds of feeling, have all grown up in ways of which at present we can give no account. Even in the clearest parts of Psychology our insight is insignificant enough. And the more sincerely one seeks to trace the actual course of psychogenesis, the steps by which as a race we may have come by the peculiar mental attributes which we possess, the more clearly one perceives "the slowly gathering twilight close in utter night."

THE END.

INDEX.

A. B. C. D. E. F. G. H. I. J. K. L. M. N. O. P. Q. R. S. T. U. V. W. X. Y. Z.

Authors the titles only of whose works are cited are not, as a rule, referred to in this index.

Abbott, T. K., II. 221 Abstract ideas, I. 468, 508; II. 48 Abstract qualities, II. 329-37, 340 Abstraction, I. 505; II. 346 ff. See distraction Accommodation, feeling of, II. 93, 235 Acquaintance, I. 220 Acquired characters, see inheritance Acquisitiveness, II. 422, 679 Actors, their emotions whilst playing, II. 464 Adaptation of mind to environment results in our knowing the impressing circumstances, II. 625 ff. Æsthetic principles, II. 639, 672 After-images, I. 645-7; II. 67, 200, 604 Agoraphobia, II. 421 Agraphia, I. 40, 62 Alfieri, II. 543 Allen, G., I. 144; II. 631 Alteration of one impression by another one simultaneously taking place, II. 28 ff., 201 Alternating personality, I. 379 ff. Ambiguity of optical sensations, II. 231-7 Amidon, I. 100 Amnesia in hysterical disease, I. 384 ff.; accompanies anæsthesia, 386, 682; in hypnotic trance, II. 602. See forgetting Amputated limbs, feeling of, II. 38-9, 105 Anæsthesia, in hysterics, I. 203 ff.; involves correlated amnesia, 386; movements executed during, II. 105, 489-92, 520-1; and emotion, 455-6; in hypnotism, 606-9 Analogies, the perception of, I. 530 Analysis, I. 502; II. 344 Anger, II. 409, 460, 478 Aphasia, motor, I. 37, 62; sensory, I. 53-4-5; optical, I. 60; amnesia in, 640, 684; II. 58 Apperception, II. 107 ff. Apperception, transcendental Unity of, I. 362 Appropriateness, characterizes mental acts, I. 13 Apraxia, I. 52 A priori connections exist only between objects of perception and movements, not between sensory ideas, II. 581. A priori ideas and experience, Chapter XXVIII. A priori propositions, II. 661-5 Archer, W., II. 464 Arithmetic, II. 654. Articular sensibility, II. 189 ff. Association, Chapter XIV: is not of ideas, but of things thought of, I. 554; examples of, 555 ff.; its rapidity, 557 ff.; by contiguity, 561; elementary law of, 566; 'mixed' association, 571; conditions of, 575 ff.; by similarity, 578; three kinds of association compared, 580; in voluntary thought, 583; by contrast, 593; history of the doctrine of, 594; association the means of localization, II. 158 ff.; connection of association by similarity with reasoning, 345 ff. Associationism, I. 161 Associationist theory of the self, I. 342, 350 ff.; of space-perception, II. 271 ff. Asymbolia, I. 52 Attention, Chapter XI: to how many things possible, I. 405 ff.; to simultaneous sight and sound, 411 ff.; its varieties, 416; passive, 417; voluntary, 42 ff.; its effects, 424 ff.; its influence on reaction-time, 427-34; accompanied by feelings of tension due to adaptation of sense-organs, 434-8; involves imagination or preperception of object, 438-44; conceivable as a mere effect, 448 ff. Aubert, H., II. 235 Auditory centre in brain, I. 52-6 Auditory type of imagination, II. 60 'Ausfallserscheinungen,' I. 75 Automatic writing, I. 393 ff. Austen, Jane, I. 571 Automaton-Theory, Chapter V: postulated rather than proved, I. 134-8; reasons against it, 138-144; applied to attention, 448 disregarded in this book, II. 583 Azam, Dr., I. 380. Babe and candle, scheme of, I. 25 Baby's first perception, II. 8, 84; his early instinctive movements, 404 ff. Baer, von, I. 639 Bagehot, W., I. 582; II. 283, 308 Bain, on series conscious of itself, I. 162; on self-esteem, 313; on self-love, 328, 354; on attention, 444; on association, 485, 530, 561, 589, 601, 653; II. 6, 12, 69, 186, 271, 282, 296, 319, 322, 372-3, 463, 466, 551, 554-5 Ballard, I. 266 Balzac, I. 374 Bartels, I. 432 Bastian, H. C., II. 488 Baumann, II. 409 Baxt, I. 648 Beaunis, E., II. 492 Bechterew, I. 407 Belief, Chapter XXI: in sensations, II. 299 ff.; in objects of emotion, 306 ff.; in theories, 311 ff.; and will, 319. See reality Bell, C., II. 483, 492 Bergson, J., II. 609 Berkeley, I. 254, 469, 476; II. 43, 49, 77, 212, 240, 666 Bernhardt, II. 502 Bernheim, I. 206 Bertrand, A., II. 518 Bessel, I. 413 Binet, A., I. 203 ff.; II. 71, 74, 128 ff., 130, 167, 491, 520 Black, R. W., II. 339 Bleek, II. 358 Blind, the, their space-perception, II. 202 ff.; after restoration to sight, 211-2; hallucination of a blind man, 323; dreams of the, 44 Blindness, mental, I. 41, 50, 66. See Sight, Hemianopsia, etc. Blix, II. 170 Bloch, II. 515 Blood, its exciting effect on the nerves, II. 412-3 Blood, B. P., II. 284 Blood-supply to brain, I. 97 Bourne, A., I. 391 Bourru, Dr., I. 388 Bowditch, H. P., his reaction-timer, I. 87; on contrast in seen motion, II. 247; on knee-jerk, 380; comparison of touch and sight, 520 Bowen, F., I. 214 Bowne, B. P., on knowledge, I. 219 Bradley, F. H., I. 452, 474, 604; II. 7, 9, 284, 648 Brain, its functions, Chapter II: of frog, I. 14; of dog, 33; of monkey, 34; of man, 36; lower centres compared with hemispheres, 9-10, 75; circulation in, 97; instability, 139; its connection with Mind, 176; 'entire' brain not a real physical fact, 176; its changes as subtle as those of thought, 234; its dying vibrations operative in producing consciousness, 242 Influence of environment upon it, 626 ff. Brain-process, see neural process Brain-structure, the two modes of its genesis, II. 624 Brentano, I. 187, 547 Bridgeman, Laura, II. 62, 358, 420 Broca's convolution, I. 39, 54 Brodhun, I. 542 Brown, Thos., I. 248, 277, 371; II. 271 Brown-Séquard, I. 43, 67, 69; II. 695 Brutes, the intellect of, II. 348 ff. Bucke, R. M., II. 460 Bubnoff, I. 82 Burke, II. 464 Burnham, W. H., I. 689 Burot, Dr., I. 388 Caird, E., I. 366, 469, 471; II. 11 Calmeil, A., II. 524 Campanella, II. 464 Campbell, G., I. 261 Cardaillac, I. 247 Carlyle, T., I. 311 Carpenter, W. B., on formation of habits, I. 110; ethical remarks on habit, 120; mistakes in speech, 257; lapses of memory, 374; on not feeling pain, 419; on ideo-motor action, II. 522 Carville, I. 69 Catalepsy, I. 229; II. 583 Cattell, on reaction-time, I. 92, 432; 524; on recognition, 407, 648; on attention, 420; on association-time, 558 ff. Cause, consciousness a, I. 187; II. 583, 592 Centres, cortical, I. 30 ff.; motor, 31; visual, 41; auditory, 52; olfactory, 57; gustatory, 58; tactile, 58 Cerebral process, see neural process Cerebrum, see Brain, Hemispheres Chadbourne, P A., II. 383 Characters, general, II. 329 ff. Charcot, I. 54-5; II. 58, 596 Chloroform, I. 531 Choice, see selection, interest Circulation in brain, I. 97; effects of sensory stimuli upon, II. 374 ff.; in grief, 443-4 Classic and romantic, II. 469 Classifications, II. 646 Clay, E. C. R., I. 609 Cleanliness, II. 434 Clearness, I. 426 Clifford, I. 130-2 Clouston, II. 114, 284-5, 537, 539 Cobbe, F. P., I. 374 Cochlea, theory of its action, II. 169 Cognition, see knowing Cohen, H., I. 365 Coleridge, S. T., I. 572, 681 Collateral innervation, see vicarious function Comparison, Chapter XIII: relations discovered by comparison have nothing to do with the time and space order of their terms, II. 641; mediate, 489, 644; see difference, likeness Composition, of Mind out of its elements, see Mind-Stuff theory; differences due to, I. 491 Comte, A., I. 187 Conceivability, I. 463 Conceptions, Chapter XII: defined, I. 461; their permanence, 464 ff.; do not develop of themselves, 466 ff.; abstract, 468; universal, 478; essentially teleological, II. 332 Conceptual order different from perceptual, I. 482 Concomitants, law of varying, I. 506 Confusion, II. 352 Consciousness, its seat, I. 65; its distribution, 142-3; its function of selection, 139-41; is personal in form, 225; is continuous, 237, 488; of lack, 251; of self not essential, 273; of object comes first, 274; always partial and selective, 284 ff., see Selection; of the process of thinking, 300 ff.; the span of, 405 Consent, in willing, II. 568 Considerations, I. 20 Constructiveness, II. 426 Contiguity, association by, I. 561 Continuity of object of consciousness, I. 488 Contrast, of colors, II. 13-27; of temperatures, 14; two theories of, 17 ff., 245; of movements, 245 ff., 250 Convolutions, motor, I. 41 Cortex, of brain, experiments on, I. 31 ff. Cramming, I. 663 Credulity, our primitive, II. 319 Cudworth, R., II. 9 'Cue,' the mental, II. 497, 518 Cumberland, S., II. 525 Curiosity, II. 429 Czermak, II. 170, 175 Darwin, C., II. 432, 446, 479, 484, 678, 681-2-4 Darwinism, scholastic reputation of, II. 670 Data, the, of psychology, I. 184 Davidson, T., I. 474 Deaf-mute's thought in infancy, I. 266 Deafness, mental, I. 50, 55-6. See hearing Dean, S., I. 394 Decision, five types of, II. 531 Degenerations, descending in nerve-centres, I. 37, 52 Delabarre, E., II. 13-27, 71 Delbœuf, J., I. 455, 531, 541, 542, 548-9; II. 100, 189, 249, 264, 605, 609, 612 Deliberation, II. 528 ff. Delusions, insane, I. 375; II. 114 ff. Depth, see third dimension Descartes, I. 180, 200, 214, 344 Destutt de Tracy, I. 247 Determinism must be postulated by psychology, II. 576 Dewey, J., I. 473 Dichotomy in thinking, II. 654 Dickens, C., I. 374 Dietze, I. 407, 617 Difference, not resolvable into composition, I. 490; noticed most between species of a genus, 529; the magnitude of, 531; least discernible, 537 ff.; methods for ascertaining, 540 ff. Difference, local, II. 167 ff.; genesis of our perception of, 642 Diffusion of movements, the law of, II. 372 Dimension, third, II. 134 ff., 212 ff., 220 Dipsomania, II. 543 Disbelief, II. 284 Discrimination, Chapter XIII: conditions which favor it, I. 494; improves by practice, 508; spatial, II. 167 ff. See difference Dissociation, I. 486-7; law of, by varying concomitants, 506 Dissociation, ditto, II. 345, 359 Dissociation, of one part of the mind from another, see Janet, Pierre Distance, between terms of a series, I. 530 Distance, in space, see third dimension Distraction, I. 401. See inattention Dizziness, see vertigo Dog's cortical centres, after Ferrier, I. 33; after Munk, I. 44-5; after Luciani, I. 46, 53, 58, 60; for special muscles, 64; hemispheres ablated, 70 Donaldson, II. 170 Donders, II. 235 Double images, II. 225-30, 252 Doubt, II. 284, 318 ff.; the mania of, 545 Dougal, J. D., II. 222 Drainage of one brain-cell by another, II. 583 ff. Dreams, II. 294 Drobisch, I. 632, 660 Drunkard, II. 565 Drunkenness, I. 144; II. 543, 565, 628 Dualism of object and knower, I. 218, 220 Duality, of Brain, I. 390, 399 Dudley, A. T., on mental qualities of an athlete, II. 539 Dufour, II. 211 Dunan, Ch., II. 176, 206, 208-9 Duration, the primitive object in time-perception, I. 609; our estimate of short, 611 ff. 'Dynamogeny,' II. 379 ff., 491 Ebbinghaus, H., I. 548, 676 Eccentric projection of sensations, II. 31 ff., 195 ff. Education of hemispheres, I. 76 See pedagogic remarks Effort, II. 534-7; Muscular effort, 562; Moral effort, 549, 561, 578-9 Egger, V., I. 280-1-2; II. 256 Ego, Empirical, I. 291 ff.; pure, 342 ff.; 'transcendental,' 362; criticised, 364 Elementary factors of mind, see Units of consciousness Elsas, I. 548 Emerson, R. W., I. 582, II. 307 Emotion, Chapter XXV: continuous with instinct, II. 442; description of typical emotions, 443-9; results from reflex effects of stimulus upon organism, 449 ff.; their classification, 454; in anæsthetic subjects, 455; in the absence of normal stimulus, 458-60; effects of expressing, 463 ff.; of repressing, 466; the subtler, 469 ff.; the neural process in, 472; differences in individuals, 474; evolution of special emotions, 477 ff. Empirical ego, I. 290 Empirical propositions, II. 644 Emulation, II. 409 Ennui, I. 626 Entoptic sensations, I. 515 ff. Equation, personal, I. 413 'Equilibration,' direct and indirect, II. 627 Essences, their meaning, II. 329 ff.; sentimental and mechanical, 665 Essential qualities, see essences Estel, I. 613, 618 Evolutionism demands a 'mind-dust,' 146 Exner, on human cortical centres, I. 36; on 'circumvallation' of centres, 65; his psychodometer, 87; on reaction-time, 91; on perception of rapid succession, 409; on attention, 439; on time-perception, 615, 638, 646; on feeling of motion, II. 172 Experience, I. 402, 487; Relation of experience to necessary judgments, Chapter XXVIII; Experience defined, II. 619 ff., 628 Experimentation in psychology, I. 192 Extradition of sensations, II. 31 ff., 195 ff. Fallacy, the Psychologist's, I. 196, 278, 153; II. 281 Familiarity, sense of, see recognition Fatalism, II. 574 Fatigue, diminishes span of consciousness, I. 640 Fear, instinct of, II. 396, 415; the symptoms of, 446; morbid, 460; origin of, 478 Fechner, I. 435-6, 533, 539 ff., 549, 616, 645; II. 50, 70, 137 ff., 178, 464 Feeling, synonym for consciousness in general in this book, I. 186; feelings of relation, 243 Félida X., I. 380-4 Féré, Ch., II. 68, 378 ff. Ferrier, D., I. 31, 46-7-8, 53, 57-8-9, 445; II. 503 Ferrier, Jas., I. 274, 475 Fiat, of the will, II. 501, 526, 561, 564; 568. See decision Fichte, I. 365 Fick, I. 150 Fiske, J., II. 577 Fixed ideas. See insistent ideas Flechsig's Pyramidenbahn, I. 37 Flint, R., II. 425 Flourens, P., I. 30 Force, supposed sense of, II. 518 Forgetting, I. 679 ff.; II. 370-1. See amnesia Fouillée, A., II. 500, 570 François-Franck, I. 70 Franklin, Mrs. C. L., II. 94 Franz, Dr., II. 63 Freedom, of the will, II. 569 ff. 'Fringe' of object, I. 258, 281-2, 471-2, 478 Frog's nerve-centres, I. 14 Fusion of feelings unintelligible, I. 157-62; II. 2. See Mind-stuff theory Fusion of impressions into one object, I. 484, 502; II. 103, 183 Galton, F., I. 254, 265, 685; on mental imagery, II. 51-7; on gregariousness, 430 General propositions, what they involve, II. 337 ff. See universal conceptions Genesis of brain-structure, its two modes, II. 624 Genius, I. 423, 530; II. 110, 352, 360 Gentleman, the mind of the, II. 370 Geometry, II. 658 Giddiness, see vertigo Gilman, B. I., I. 95 Gley, E., II. 514-5, 525 Goldscheider, II. 170, 192 ff., 200 Goltz, I. 9, 31, 33, 34, 45, 46, 58, 62, 67, 69, 70, 74, 77 Gorilla, II. 416 Graefe, A., II. 507, 510 Grashey, I. 640 Grassman, R., II. 654 Gregariousness, II. 430 Green, T. H., I. 247, 274, 366-8; II. 4, 10, 11 Grief, II. 448, 480 Griesinger, W., II. 298 Grübelsucht, II. 284 Guinea-pigs, epileptic, etc., II. 682-7 Guislain, II. 546 Gurney, E., I. 209; II. 117, 130, 469, 610 Guyau, II. 414, 469 Habit, Chapter IV: due to plasticity of brain-matter, I. 105; depends on paths in nerve-centres, 107; origination of, 109-13; mechanism of concatenated habits, 114-8; they demand some sensation, 118; ethical and pedagogic maxims, 121-7; is the ground of association, 566; of memory, 655 Habits may inhibit instincts, II. 394; Habit accounts for one large part of our knowledge, 632 Hall, G. S., I. 96-7, 558, 614, 616; II. 155, 247, 281, 423 Hallucination, sensation a veridical, II. 33; of lost limbs, 38, 105; of emotional feeling, 459 Hallucinations, II. 114 ff.; hypnagogic, 124; the brain-process in, 122 ff.; hypnotic, 604 Hamilton, W., I. 214, 215, 274, 406, 419, 569, 578, 682; II. 113 Hammond, E., II. 673 Haploscopic method, II. 226 Harless, II. 497 Hartley, I. 553, 561, 564, 600 Hartmann, R., II. 416 Hasheesh-delirium, II. 121 Hearing, its cortical centre, I. 52 Heat, of mental work, I. 100 Hecker, II. 480 Hegel, I. 163, 265, 366, 369, 666 Heidenhain, I. 82 Helmholtz, H., I. 285; on attention, 422, 487, 441; on discrimination, 504, 516-21; time as a category, 637-8; after-images, 645, 648; on color-contrast, II. 17 ff.; on sensation, 33; on cochlea, 170; on convergence of eyes, 200; vision with inverted head, 213; on what marks a sensation, 218 ff., 243-4; on entoptic objects, 241-2; on contrast in seen movement, 247; on relief, 257; on measurement of the field of view, 266 ff.; on theory of space-perception, 279; on feeling of innervation, 493, 507, 510; on conservation of energy, 667 Hemiamblyopia, I. 44 Hemianopsia, I. 41, 44; II. 73 Hemispheres, their distinction from lower centres, I. 20; their education, 24, 67; localization of function in, 30; the exclusive seat of consciousness, 65; effects of deprivation of, on frogs, 17, 72-3; on fishes, 73; on birds, 74, 77; on rodents, 74; on dogs, 70, 74; on primates, 75; not devoid of connate paths, 76; their evolution from lower centres, 79 Henle, J., II. 445, 461, 481 Herbart, I. 353, 418, 603, 608, 626 Hereditary transmission of acquired characters, see inheritance Hering, E., on attention, I. 438, 449; on comparing weights, 544; on pure sensation, II. 4; on color-contrast, 20 ff.; on roomy character of sensations, 136 ff.; on after-images and convergence, 200; on distance of double images, 230; on stereoscopy, 252; on reproduction in vision, 260 ff.; on movements of closed eye, 510 Herzen, I. 58; on reaction-time from a corn, 96; on cerebral thermometry, 100; on swooning, 273 Hitzig, I. 31 Hobbes, T., I. 573, 587, 594 ff. Hodgson, R., I. 374, 398 Hodgson, S. H., on inertness of consciousness, I. 129-30, 133; on self, 341, 347; on conceptual order, 482; on association, 572 ff., 603; on voluntary redintegration, 588-9; on the 'present' in time, 607 Höffding, H., I. 674; II. 455 Holbrook, M. H., I. 665 Holmes, O. W., I. 88, 405, 582 Holtei, von, I. 624 Horopter, II. 226 Horsley, V., I. 35, 59, 63 Horwicz, I. 314, 325-7 Howe, S. G., II. 358 Human intellect, compared with that of brute, II. 348 ff.; depends on association by similarity, 353 ff.; various orders of, 360; what brain-peculiarity it depends on, 366, 638 Hume, I. 254; on personal identity, 351-3, 360; association, 597; due to brain-laws, 564; on mental images, II. 45-6; on belief, 295-6, 302; on pleasure and will, 558 Hunting instinct, II. 411 Huxley, I. 130-1, 254; II. 46 Hyatt, A., II. 102 Hylozoism, see Mind-stuff theory Hyperæsthesia, in hypnotism, II. 609 Hypnotism, I. 407; II. 128, 351; general account of, Chapter XXVII; methods, II. 593; theories of, 596; symptoms of trance, 602 ff.; post-hypnotic suggestion, 618 Hysterics, their so-called anæsthesias, and unconsciousness, I. 202 ff. Ideal objects, eternal and necessary relations between, II. 639, 661. See conceptions 'Ideas,' the theory of, I. 230; confounded with objects, 231, 276, 278, 399, 521; they do not exist as parts of our thought, 279, 405, 553; platonic, 462; abstract, 468 ff.; universal, 473 ff.; never come twice the same, 480-1 Ideation, no distinct centres for, I. 564; II. 78 Identity, sense of, I. 459; three principles of, 460; not the foundation of likeness, 492 Identity, personal, I. 238, 330 ff.; based on ordinary judgment of sameness, 334; due to resemblance and continuity of our feelings, 336; Lotze on, 350; only relatively true, 372 Ideo-motor action the type of all volition, II. 522 Idiosyncrasy, II. 631 'Idomenians,' II. 214 Illusions, II. 85 ff., 129, 232 ff., 243-66. See hallucinations Images, double, in vision, II. 225-30 Images, mental, not lost in mental blindness, etc., I. 50, 66; II. 73 Images, are usually vague, II. 45; visual, 51 ff.; auditory, 160; motor, 61; tactile, 165; between sleep and waking, 124-6 Imagination, Chapter XVIII: it differs in individuals, II. 51 ff.; sometimes leaves an after-image, 67; the cerebral process of, 68 ff.; not locally distinct from that of sensation, 73; is figured, 82 Imitation, II. 408 Immortality, I. 348-9 Impulses, morbid, II. 542 ff. See instincts Impulsiveness of all consciousness, II. 526 ff. Inattention, I. 404, 455 ff. Increase, serial, I. 490 Indeterminism, II. 569 ff. Ingersoll, R., II. 469 Inheritance of acquired characters, II. 367, 678 ff. Inhibition, I. 43, 67, 404; II. 126, 373; of instincts, 391, 394; of one cortical process by another, 583 Innervation, feeling of, II. 236, 493; it is unnecessary, 494 ff.; no evidence for it, 499, 518 Innervation, collateral, see vicarious function Insane delusions, I. 375; II. 113 Insistent ideas, II. 545 Instinct. Chapter XXIV; defined, II. 384; is a reflex impulse, 385 ff.; is neither blind nor invariable, 389; contrary instincts in same animal, 392; man has more than other mammals, 393, 441; their transitoriness, 398; special instincts, 404-441; the origin of instincts, 678 'Integration' of feelings, Spencer's theory of, I. 151 ff. Intelligence, the test of its presence, I. 8; of lower brain-centres, 78 ff. Intention to speak, I. 253 Interest, I. 140, 284 ff., 402-3, 482, 515 ff., 572, 594; II. 312 ff., 344-5, 634 Intermediaries, the axiom of skipped, II. 646 Introspection, I. 185 Inverted head, vision with, II. 213 Jackson, Hughlings, I. 29, 64, 400; II. 125-6 Janet, J., I. 385 Janet, Paul, I. 625; II. 40-1 Janet, Pierre, I. 203 ff., 227, 384 ff., 682; II. 456, 614 Jastrow, I. 88, 543, 545; II. 44, 135, 180 Jevons, W. S., I. 406 Joints, their sensibility, II. 189 ff. Judgments, existential, II. 290 Justice, II. 673 Kandinsky, V., II. 70, 116 Kant, I. 274, 331, 344, 347; his 'transcendental' deduction of the categories, 360; his paralogisms, 362; criticised, 363-6; on time, 642; on symmetrical figures, II. 150; on space, 273 ff.; on the real, 296; on synthetic judgments a priori, 661, and their relation to experience, 664 Kinæsthetic feelings, II. 488 ff., 493 'Kleptomania,' II. 425 Knee-jerk, II. 380 Knowing, I. 216 ff.; psychology assumes it, 218; not reducible to any other relation, 219, 471, 688 Knowledge, two kinds of, I. 221; of Self not essential to, 274; the relativity of, II. 9 ff.; the genesis of, 630 ff. Knowledge-about, I. 221 König, I. 542 Kries, von, I. 96, 547; II. 253 Krishaber, I. 377 Kussmaul, A., I. 684 Ladd, G. T., I. 687; II. 3, 311 Lamarck, II. 678 Landry, II. 490, 492 Lange, A., I. 29, 284 Lange, C., II. 443, 449, 455, 457, 460, 462 Lange, K., II. 111 Lange, L., on reaction-time, muscular and sensorial, I. 92 Lange, N., on muscular element in imagination, I. 444 Language, as a human function, II. 356-8 Laromiguèire, I. 247 Laughter, II. 480 Lazarus, I. 624, 626; II. 84, 97, 369, 429 Le Conte, Joseph, II. 228, 252, 265 Léonie, M. Janet's trance-subject, I. 201, 387 ff. Levy, W. H., II. 204 Lewes, on frog's sp. cord, I. 9, 78, 134; on thought as a sort of algebra, 270; on 'preperception,' 439, 442; on muscular feeling, II. 199; on begging in pup, 400; on lapsed intelligence, 678 Lewinski, II. 192 Liberatore, II. 670 Liebmann, O., on brain as a machine, I. 10; II. 34 Liégeois, J., II. 594, 606 Light, effects of, on movement, II. 379 Likeness, I. 528 Lindsay, T. L., II. 421 Lipps, on 'unconscious' sensations, I. 175; on theory of ideas, 603; time-perception, 632; on muscular feeling, II. 200; on distance, 221; on visual illusions, 251, 264; on space-perception, 280; on reality, 297; on effort, 575 Lissauer, I. 50 Local signs, II. 155 ff., 167 Localization, in hemispheres, I. 30 ff. Localization, II. 153 ff.; of one sensible object in another, II. 31 ff., 183 ff., 195 ff. Locke, J., I. 200, 230, 247, 349, 390, 462, 483, 553, 563, 679; II. 210, 306, 644, 662-4 'Locksley Hall,' I. 567 Locomotion, instinct of, II. 405 Loeb, I. 33, 44; II. 255, 516, 628 Logic, II. 647 Lombard, J. S., I. 99 Lombard, W., II. 380 Lotze, I. 214; on immortality, 349; on personal identity, 350; on attention, 442-3; on fusion and discrimination of sensations, 522; on local signs, II. 157, 495; on volition, 523-4 Louis V., I. 388 Love, sexual, II. 437, 543; parental, 439; Bain's explanation of, 551 Lowell, J. R., I. 582 Luciani, I. 44-5-6-7, 53, 60 McCosh, I. 501 Mach, E., on attention, I. 436; on space-feeling, 449; on time feeling, 616, 635; on motion-contrast, II. 247; on optical inversion, 255; on probability, 258; on feeling of innervation, 509, 511 Magnitude of differences, I. 530 ff. Malebranche, II. 9 Manouvrier, II. 496 Mania, transitory, II. 460 Man's intellectual distinction from brutes, II. 348 ff. Mansel, H. L., I. 274 Mantegazza, P., II. 447, 479, 481 Marcus Aurelius, I. 313, 317; II. 675 Marillier, L., I. 445; II. 514 Marique, I. 65 Martin, H. N., I. 99; II. 3 Martineau, J., I. 484 ff., 506; II. 9 Maudsley, H., I. 113, 656 Maury, A., II. 83, 124, 127 Mechanical philosophy, the, II. 666 ff. Mechanism vs. intelligence, I. 8-14 Mediate comparison, I. 489 Mediumship, I. 228, 393 ff. Mehner, I. 618 Memory, Chapter XVI: it depends on material conditions, I. 2; the essential function of the hemispheres, 20; lapses of, 373 ff.; in hysterics, 384 ff.; favored by attention, 427; primary, 638, 643; analysis of the phenomenon of Memory, 648; the return of a mental image is not memory, 619; memory's causes, 653 ff.; the result of association, 654; conditions of good memory, 659; brute retentiveness, 660; multiple associations, 662; improvement of memory, 667 ff.; its usefulness depends on forgetting much, 680; its decay, 683; metaphysical explanations of it, 687 ff. Mentality, the mark of its presence, I. 8 Mental operations, simultaneous, I. 408 Mercier, C., on inertness of consciousness, I. 135; on inhibition, II. 583 Merkel, I. 542-3-4 Metaphysical principles, II. 669 ff. Metaphysics, I. 137, 401 Meyer's experiment on color-contrast, II. 21 Meyer, G. H., II. 66, 97-8 Meynert, T., his brain-scheme, I. 25, 64, 72 Mill, James, I. 277, 355, 470, 476, 485, 499, 597, 651, 653; II. 77 Mill, J. S., I. 189; on unity of self, 356-9; on abstract ideas, 470; methods of inquiry, 590; on infinitude and association, 600; on space, II. 271; on belief, 285, 322; on reasoning, 331; on the order of Nature, 634; on arithmetical propositions, 654 Mills, C. K., I. 60 Mimicry, its effects on emotion, II. 463-6 Mind, depends on brain-conditions, I. 4, 553; the mark of its presence, 8; difficulty of stating its connection with brain, 176; what psychology means by it, 183, 216 Mind-Stuff theory, Chapter VI: a postulate of evolution, I. 146, 176; some proofs of it, 148; author's interpretation of them, 154; feelings cannot mix, 157 ff., II. 2, 103 Miser, associationist explanation of the, II. 423 ff. Mitchell, J. K., II. 616 Mitchell, S. W., I. 381; II. 38-9, 380 Modesty, II. 435 Moll, A., II. 616 Molyneux, II. 210 Monadism, I. 179 Monism, I. 366-7 Monkey's cortical centres, I. 34-5, 46, 59 Montgomery, E., I. 158 Moral principles, II. 639, 672 Morris, G. S., I. 365 Mosso, on blood-supply to brain, I. 97-9 plethysmographic researches, II. 378; on fear, 419, 483 Motor centres, I. 31 ff. 'Motor circle,' II. 583 Motor strands, I. 38; for special muscles, I. 64 Motor type of imagination, II. 61 Movement, perception of, by sensory surfaces, II. 171 ff.; part played by, in vision, 197, 203, 234-7 the, Production of, Chap. XXII requires guiding sensations, 490 illusory perception of, during anæsthesia, 489; results from every kind of consciousness, 526 Mozart, I. 255 Müller, G. E., I. 445, 456-8; II. 198, 280, 491, 502, 508, 517 Müller, J., I. 68; II. 640 Müller, J. J., II. 213 Müller, Max, I. 269 Munk, H., I. 41-3-4-5-6, 57-8-9, 63 Münsterberg, on Meynert's scheme, I. 77; on reaction times with intellectual operation, 432: on association, 562; on time-perception, 620, 637; on imagination, II. 74; on muscular sensibility, 189; on volition, 505; on feeling of innervation, 514; on association, 590 Muscles, how represented in nerve-centres, I. 19 Muscle-reading, II. 525 Muscular sense, its cortical centre, I. 61; its existence, II. 189 ff., 197 ff.; its insignificance in space-perception, 197-203, 234-7 Music, its accidental genesis, II. 627; 687 Mussey, II. 543 Mutilations, inherited, II. 627 Myers, F. W. H., I. 400; II. 133 Mysophobia, II. 435, 545 Nature, the order of, its incongruence with that of our thought, II. 634 ff. Naunyn, I. 55 Necessary truths are all truths of comparison, II. 641 ff., 651, 662. See experience, a priori connections, etc. Neiglick, I. 543 Neural process, in perception. I. 78 ff.; in habit, 105 ff.; in association, 566; in memory, 655; in imagination, II. 68 ff.; in perception, 82 ff., 103 ff.; in hallucination, 122 ff.; in space-perception, 143; in emotion, 474; in volition, 580 ff.; in association, 587 ff. Nitrous oxide intoxication, II. 284 Nonsense, how it escapes detection, I. 261 Normal position in vision, II. 238 Nothnagel, I. 51, 60-1 Number, II. 653 Obersteiner, I. 87, 445 Object, use of the word, I. 275, 471; confusion of, with thought that knows it, 278 Objective world, known before self, I. 273; its primitive unity, 487-8; ditto, II. 8 Objects versus ideas, I. 230, 278 Old-fogyism, II. 110 Orchansky, I. 95 'Overtone' (psychic), I. 258, 281-2 Pain, I. 143, its relations to the will, II. 549 ff., 583-4 Paneth, I. 64, 65 Parallelism, theory of, between mental and cerebral phenomena, see Automaton-theory Paresis of external rectus muscle, II. 236, 507 Parinaud, II. 71 Partiality of mind, see interest, teleology, intelligence, selection, essences Past time, known in a present feeling, I. 627; the immediate past is a portion of the present duration-block, 608 ff. Patellar reflex, II. 380 Paths through cortex, I. 71; their formation, 107-12; II. 584 ff.; association depends on them, 567 ff.; memory depends on them, 655 ff., 661, 686 Paulhan, F., I. 250, 408, 670; II. 64, 476 Pedagogic remarks: I. 121-7; II. 110, 401-2, 409, 463, 466 Perception. Chapter XIX: compared with sensation, II. 1, 76; involves reproductive processes, 78; is of probable objects, 82 ff.; not an unconscious inference, 111 ff.; rapidity of, 131 Perception-time, II. 131 Perez, B., I. 446; II. 416 Personal equation, I. 413 Personality, alterations of, I. 373 ff. Pflüger, on frog's spinal cord, I. 9, 134 Philosophies, their test, II. 312 Phosphorus and thought, I. 101 Phrenology, I. 27 Pick, E., I. 669 Pitres, I. 206 Planchette-writing, I. 208-9, 393 ff. Plasticity, as basis of habit, defined, I. 105 Platner, II. 208 Plato, I. 462 Play, II. 427 Pleasure, as related to will, I. 143; II. 549, 583-4 Points, identical, theory of, II. 222 ff. Possession, Spirit-, I. 393 ff. Post-hypnotic suggestion, II. 613 Practical interests, their effects on discrimination, I. 515 ff. Prayer, I. 316 'Preperception,' I. 439 Present, the present moment, I. 606 ff. Preyer, II. 403 Probability determines what object shall be perceived, II. 82, 104, 258, 260-3 Problematic conceptions, I. 463 Problems, the process of solution of, I. 584 Projection of sensations, eccentric, II. 31 ff. Projection, theory of, II. 228 Psychologist's fallacy, the, see Fallacy Psychophysic law, I. 539 Pugnacity, II. 409 Pure Ego, I. 342 Putnam, J. J., I. 61 Questioning mania, II. 284 Rabier, I. 470, 604 Rational propositions, II. 644 Rationality is based on apprehension of series, II. 659 Rationality, postulates of, II. 670, 677 Rationality, sense of, I. 260-4; II. 647 Reaction-time, I. 87; simple, 88; what it measures is not conscious thought, 90; Lange's distinction between muscular and sensorial, 92; its variations, 94-7; influenced by expectant attention, 427 ff.; after intellectual process, 432; after discrimination, 523; after association, 557; after perception, II. 131 Real size and shape of visual objects, II. 179, 237 ff. Reality, the Perception of, Chapter XXI; not a distinct content of consciousness, II. 286; various orders of, 287 ff.; every object has some kind of reality, 291 ff.; the choice of, 290; practical, 293 ff.; means relation to the self, 295-8; relation of sensations to, 299; of emotions, 306 Reason, I. 551. See Logic Reasoning, Chapter XXII; its definition, II. 325; involves the picking out of essences, or sagacity, 329; and abstraction, 332; its utility depends on the peculiar constitution of this world, 337 ff., 651; depends on association by similarity, 345 Recall, I. 578, 654 'Recepts,' II. 327, 349, 351 Recognition, I. 673 Recollection, voluntary, I. 585 ff. Redintegration, I. 569 'Reductives,' II. 125, 291 Reflex acts, I. 12; reaction-time measures one, 90; concatenated habits are constituted by a chain of, 116 Reid, Thomas, I. 609, 78; II. 214, 216, 218, 240, 309 Relating principle, I. 687-8 Relation, feelings of, I. 243 ff.; space-relations, II. 148 ff. Relations, inward, between ideas, II. 639, 642, 661, 671; the principle of transferred, 646 Relief, II. 254-7. See third dimension Renouvier, Ch., I. 551; II. 309 Reproduction in memory, I. 574 ff., 654; voluntary, 585 ff. Resemblance, I. 528 Respiration, effects of sensory stimuli upon, II. 376 Restitution of function, I. 67 ff. Restoration of function, I. 67 ff. Retention in memory, I. 653 ff. Retentiveness, organic, I. 659 ff.; it is unchangeable, 663 ff. Retinal image, II. 92 Retinal sensibility, see vision, space, identical points, third dimension, projection, etc. Revival in memory, I. 574 ff., 654 Reynolds, Mary, I. 381 Ribot, Th., I. 375; on attention, 444, 446, 680, 682 Richet, Ch., I. 638, 644-6-7 Riehl, A., II. 32 Robertson, G. C., I. 461; II. 86 Romanes, G. J., II. 95, 132, 327-9, 349, 351, 355, 397 Romantic and classic, II. 469 Rosenthal, I. 79 Ross, J., I. 56-7 Royce, J., I. 374; II. 316-7 Royer-Collard, I. 609 Rutherford, II. 170 Sagacity, II. 331, 343 Sameness, I. 272, 459, 480; II. 650 Schaefer, W., I. 35, 53, 59, 63 Schiff, M., I. 58, 78, 100 Schmid, I. 683 Schmidt, H. D., II. 399-400 Schneider, G. H., on Habits, I. 112, 118-20; on perception of motion, II. 173; on evolution of movements, 380; on instincts, 387-8, 411, 418, 439 Schopenhauer, II. 33, 273 Schrader, I. 72 ff. Science, the genesis of, II. 665-9 Sea-sickness, susceptibility to, an accident, II. 627 Seat of consciousness, I. 65; of Soul, 214; of sensations, no original, II. 34 Sciences, the natural, the factors of their production, II. 633 ff.; a Turkish cadi upon, 640; postulate things with unchangeable properties, 656 Sciences, the pure, they express results of comparison exclusively, II. 641; classifications, 646; logic, 647; mathematics, 653 Secretiveness, II. 432 Seguin, I. 48, 75 Selection, a cardinal function of consciousness, 284 ff., 402, 594; II. 584; of visual reality, II. 177 ff., 237; of reality in general, 290, 294; of essential quality, 333, 370, 634 Self, consciousness of, Chap. X: not primary, I. 273; the empirical self, I. 291; its constituents, 292; the material self, 292; the social self, 293; the spiritual self, 296; resolvable into feelings localized in head, 300 ff.; consciousness of personal identity, 330 ff.; its alterations, 373 ff. Self-feeling, I. 305 ff. Self-love, I. 317; the name for active impulses and emotions towards certain objects; we do not love our bare principle of individuality, 323 Self-seeking, I. 307 ff. Selves, their rivalry, I. 309 ff. Semi-reflex acts, I. 13 Sensation, does attention increase its strength? I. 425; terminus of thought, 471 Sensation, Chapter XVII; distinguished from perception, II. 1, 76; its cognitive function, 3; pure sensation an abstraction, 3; the terminus of thought, 7 Sensations, are not compounds, I. 158 ff.; II. 2; their supposed combination by a higher principle, I. 687; II. 27-30; their influence on each other, II. 28-30; their eccentric projection, 31 ff., 195 ff.; their localization inside of one another, 183 ff.; their relation to reality, 299 ff.; to emotions, 453; their fusion, see Mind-stuff theory Sensationalism, I. 243; criticised by spiritualism, 687 Sensationalism, II. 5; in the field of space-perception, criticised, 216 ff.; its difficulties, 231-7; defended, 237 ff., 517 Sergi, II. 34 Serial increase, I. 490; II. 644 Series, II. 644-51, 659 ff. Seth, A., II. 4 Sexual function, I. 22 Shadows, colored, II. 25 Shame, II. 435 Shoemaker, Dr., I. 273 Shyness, II. 430 Sight, its cortical centre, I. 41 ff., 66 Sign-making, a differentia of man, II. 356 Signs, local, II. 155 ff. Sigwart, C., II. 634-6 Sikorsky, II. 465 Similarity, I. 528 Similarity, association by, I. 578; II. 345, 353 Skin, discrimination of points on, I. 512 Sleep, partial consciousness during, I. 213 Sociability, II. 430 Somnambulism, see hypnotism, hysterics Soul, theory of the, I. 180; inaccessibility of, 187; its essence is to think (according to Descartes), 200; seat of, 214; arguments for its existence, 343 ff.; an unnecessary hypothesis for psychology, 350; compared with transcendental Ego, 365; a relating principle, 499 Space, the perception of, Chapter XX; primitive extensity in three dimensions, II. 134-9; spatial order, 145; space-relations, 148; localization in, 153 ff.; how real space is mentally constructed, 166 ff.; part played by movement in, 171-6; measurement of extensions, 177 ff.; synthesis of originally chaotic sensations of extension, 181 ff.; part played by articular surfaces in, 189 ff.; by muscles, 197 ff.; how the blind perceive space, 203 ff.; visual space, 211-268; theory of identical points, 222; of projection, 228; difficulties of sensation-theory expounded and replied to, 231-268; historical sketch of opinion, 270 ff. Spalding, D. A., II. 396, 398, 400, 406 Span of consciousness, I. 405, 640 Speech, the 'centre' of, I. 55; its misleading influence in psychology, I. 194; thought possible without it, 269. See Aphasia, Phrenology Spencer, his formula of 'adjustment,' I. 6; on formation of paths in nerve-centres, 109; on chasm between mind and matter, 147; on origin of consciousness, 148; on 'integration' of nervous shocks, 151-3; on feelings of relation, 247; on unity of self, 354; on conceivability, 464; on abstraction, 506; on association, 600; on time perception, 622, 639; on memory, 649; on recognition, 673; on feeling and perception, II. 113, 180; on space-perception, 272, 282; on genesis of emotions, 478 ff.; on free-will, 576; on inheritance of acquired peculiarities, 620 ff., 679; on 'equilibration,' 627; on genesis of cognition, 643; on that of sociality and pity, 685 Spinoza, II. 288 Spir, A., II. 665, 677 'Spirit-control,' I. 228 Spiritualist theory of the self, I. 342; II. 5 Spiritualists, I. 161 Stanley, Henry M., II. 310 Starr, A., I. 54, 56 Statistical method in psychology, I. 194 Steiner, I. 72-3 Steinthal, I. 604; II. 107-9 Stepanoff, II. 170 Stereoscope, II. 87 Stereoscopy, II. 223, 252. See third dimension Sternberg, II. 105, 515 Stevens, I. 617 Stevens, E. W., I. 397 Story, Jean, I. 263 Stream of Thought, Chapter IX: schematic representations of, I. 279-82 Stricker, S., II. 62 ff. Strümpell, A., I. 376, 445, 489, 491 Strümpell, Prof., II. 353 Stuart, D., I. 406, 427 Stumpf. C, on attention, I. 426; on difference, 493; on fusion of impressions, 522, 530-3; on strong and weak sensations, 547; on relativity of knowledge, II. 11; on sensations of extent, 219, 221 Subjective sensations, I. 516 ff. Substance, spiritual, I. 345 Substantive states of mind, I. 243 Substitution of parts for wholes in reasoning, II. 330; of the same for the same, 650 Subsumption, the principle of mediate, II. 648 Succession, not known by successive feelings, I. 628; vs. duration, 609 Suggestion, in hypnotism, II. 598-601; post-hypnotic, 613 Suicide, I. 317 Sully, J., I. 191; II. 79, 221, 272, 281, 322, 425 Summation of stimuli, I. 82; of elements of feeling, 151; the latter is inadmissible, 158 Superposition, in space-measurements, II. 177, 266 ff. Symbols as substitutes for reality, II. 305 Sympathy, II. 410 Synthetic judgments a priori, II. 661-2 Systems, philosophic, sentimental, and mechanical, II. 665-7 Tactile centre, I. 58 Tactile images, II. 65 Tactile sensibility, its cortical centre, I. 34, 61, 62 Taine, H., on unity of self, I. 355; on alterations of ditto, 376; on recollecting, 658, 670; On projection of sensations, II. 33; on images, 48, and their 'reduction,' 125-6; on reality, 291 Tàkacs, II. 490 Tarde, G., I. 263 Taylor, C. F., II. 99 Tedium, I. 626 Teleology, created by consciousness, I. 140-1; essence of intelligence, 482 involved in the fact of essences, II. 335; its barrenness in the natural sciences, 665 Tendency, feelings of, I. 250-4 Thackeray, W. M., II. 434 Thermometry, cerebral, I. 99 'Thing,' II. 184, 259 Thinking, the consciousness of, I. 300 ff. Thinking principle, I. 342 Third dimension of space, II. 134 ff., 212 ff., 220 Thompson, D. G., I. 354; II. 662 Thomson, Allen, I. 84 Thought, synonym for consciousness at large, I. 186; the stream of, Chapter IX: it tends to personal form, 225; same thought never comes twice, 231 ff.; sense in which it is continuous, 237; can be carried on in any terms, 260-8; what constitutes its rational character, 269; is cognitive, 271; not made up of parts, 276 ff., II. 79 ff.; always partial to some of its objects, I. 284 ff.; the consciousness of it as a process, 300 ff.; the present thought is the thinker, 369, 401; depends on material conditions, 553 'Thought reading,' II. 525 Time, occupied by neural and mental processes, see reaction-time Time, unconscious registration of, I. 201 Time, the perception of, Chapter XV; begins with duration, I. 609; compared with perception of space, 610 ff.; empty time not perceived, 619; its discrete flow, 621, 637; long intervals conceived symbolically, 622 ff.; variations in our estimate of its length, 623 ff.; cerebral process underlying, 627 ff. Tischer, I. 524, 527 Touch, cortical centre for, I. 58 Trance, see hypnotism Transcendentalist theory of the Self, I. 342, 360 ff.; criticised, 363 ff. Transitive states of mind, I. 243 ff. Tschisch, von, I. 414, 560 Tuke, D. H., II. 130, 413 Taylor, E. B., II. 304 Tympanic membrane, its tactile sensibility, II. 140 Tyndall, I. 147-8 Ueberweg, I. 187 Unconscious states of Mind, proofs of their existence, I. 164 ff.; Objections, 164 ff. Unconsciousness, I. 199 ff.; in hysterics, 202 ff.; of useless sensations, 517 ff. Understanding of a sentence, I. 281 Units, psychic, I. 151 Unity of original object, I. 487-8; II. 8, 183 ff. Universal conceptions, I. 473. See general propositions Unreality, the feeling of, II. 298 Valentin, I. 557 Varying concomitants, law of dissociation by, I. 506 Vennum, Lurancy, I. 397 Ventriloquism, II. 184 Verdon, R., I. 685 Vertigo, II. 89; Mental vertigo, 309; optical, 506 Vicarious function of brain-parts, I. 69, 142; II. 592 Vierordt, I. 616 ff.; II. 154, 172 Vintschgau, I. 95-6 Vision with head upside down, II. 213 Visual centre in brain, I. 41 ff. Visual space, II. 211 ff. Visualizing power, II. 51-60 Vocalization, II. 407 Volition, see Volkmann, A. W., II. 198, 252 ff. Volkmann, W. von Volkmar, I. 627, 629, 631; II. 276 Voluminousness, primitive, of sensations, II. 184 Voluntary thinking, I. 583 Vulgarity of mind, II. 370 Vulpian, I. 73 Wahle, I. 493 Waitz, Th., I. 405, 632; II. 436 Walking, in child, II. 405 Walter. J. E., I. 214 Ward, J., I. 162, 454, 548, 562, 629, 633; II. 282 Warren, J. W., I. 97 Wayland, I. 347 Weber, E. H., his 'law,' I. 537 ff. On space-perception on skin, II. 141-2; on muscular feeling, 198 Weed, T., I. 665 Weissmann, A., II. 684 ff. Wernicke's convolution, I. 39, 54-5 'Wheatstone's experiment,' II. 326-7 Wigan, Dr., I. 390, 675; II. 566-7 Wilbrand, I. 50-1 Will, Chapter XXVI; involves memory of past acts, and nothing else but consent that they shall occur again, II. 487-518; the memory may involve images of either resident or remote effects of the movement, 518-22; ideo-motor action, 522-8; action after deliberation, 528; decision, 531; effort, 535; the explosive will, 537; the obstructed will, 546; relation of will to pleasure and pain, 549 ff.; to attention, 561; terminates in an 'idea', 567; the question of its indeterminism, 569; psychology must assume determinism, 576; neural processes concerned in education of the will, 579 ff. Will, relations of, to Belief, II. 320 Wills, Jas., I. 241 Witchcraft, II. 309 Wolfe, H. K., I. 674, 679 Wolff, Chr., I. 409, 651 World, the peculiar constitution of the, II. 337, 647, 651-2 Writing, automatic, I. 393 ff. Wundt, on frontal lobes, I. 64; on reaction-time, 89-94, 96, 427 ff., 525; on introspective method, 189; on self-consciousness, 303; on perception of strokes of sound, 407; on perception of simultaneous events, 411 ff.; on Weber's law, 534 ff.; association-time, 557, 560; on time-perception, 608, 612 ff., 620, 634. On local signs, II. 155-7; on eyeball-muscles, 200; on sensations, 219; on paresis of ext. rectus, 236; on contrast, 250; on certain illusions, 264; on feeling of innervation, 266, 493; on space as synthesis, 276; on emotions, 481; on dichotomic form of thought, 654 Zöllner's pattern, II. 232