Chapter XXX: Epilogue: Psychology and Philosophy

=What the Word Metaphysics means.=--In the last chapter we handed the question of free-will over to 'metaphysics.' It would indeed have been hasty to settle the question absolutely, inside the limits of psychology. Let psychology frankly admit that _for her scientific purposes_ determinism may be _claimed_, and no one can find fault. If, then, it turn out later that the claim has only a relative purpose, and may be crossed by counter-claims, the readjustment can be made. Now ethics makes a counterclaim; and the present writer, for one, has no hesitation in regarding her claim as the stronger, and in assuming that our wills are 'free.' For him, then, the deterministic assumption of psychology is merely provisional and methodological. This is no place to argue the ethical point; and I only mention the conflict to show that all these special sciences, marked off for convenience from the remaining body of truth (cf. p. 1), must hold their assumptions and results subject to revision in the light of each others' needs. The forum where they hold discussion is called metaphysics. Metaphysics means only an unusually obstinate attempt to think clearly and consistently. The special sciences all deal with data that are full of obscurity and contradiction; but from the point of view of their limited purposes these defects may be overlooked. Hence the disparaging use of the name metaphysics which is so common. To a man with a limited purpose any discussion that is over-subtle for that purpose is branded as 'metaphysical.' A geologist's purposes fall short of understanding Time itself. A mechanist need not know how action and reaction are possible at all. A psychologist has enough to do without asking how both he and the mind which he studies are able to take cognizance of the same outer world. But it is obvious that problems irrelevant from one standpoint may be essential from another. And as soon as one's purpose is the attainment of the maximum of possible insight into the world as a whole, the metaphysical puzzles become the most urgent ones of all. Psychology contributes to general philosophy her full share of these; and I propose in this last chapter to indicate briefly which of them seem the more important. And first, of the

=Relation of Consciousness to the Brain.=--When psychology is treated as a natural science (after the fashion in which it has been treated in this book), 'states of mind' are taken for granted, as data immediately given in experience; and the working hypothesis (see p. 6) is the mere empirical law that to the entire state of the brain at any moment one unique state of mind always 'corresponds.' This does very well till we begin to be metaphysical and ask ourselves just what we mean by such a word as 'corresponds.' This notion appears dark in the extreme, the moment we seek to translate it into something more intimate than mere parallel variation. Some think they make the notion of it clearer by calling the mental state and the brain the inner and outer 'aspects,' respectively, of 'One and the Same Reality.' Others consider the mental state as the 'reaction' of a unitary being, the Soul, upon the multiple activities which the brain presents. Others again comminute the mystery by supposing each brain-cell to be separately conscious, and the empirically given mental state to be the appearance of all the little consciousnesses fused into one, just as the 'brain' itself is the appearance of all the cells together, when looked at from one point of view.

We may call these three metaphysical attempts the _monistic_, the _spiritualistic_, and the _atomistic_ theories respectively. Each has its difficulties, of which it seems to me that those of the spiritualistic theory are _logically_ much the least grave. But the spiritualistic theory is quite out of touch with the facts of multiple consciousness, alternate personality, etc. (pp. 207-214). These lend themselves more naturally to the atomistic formulation, for it seems easier to think of a lot of minor consciousnesses now gathering together into one large mass, and now into several smaller ones, than of a Soul now reacting totally, now breaking into several disconnected simultaneous reactions. The localization of brain-functions also makes for the atomistic view. If in my experience, say of a bell, it is my occipital lobes which are the condition of its being seen, and my temporal lobes which are the condition of its being heard, what is more natural than to say that the former _see_ it and the latter _hear_ it, and then 'combine their information'? In view of the extreme naturalness of such a way of representing the well-established fact that the appearance of the several parts of an object to consciousness at any moment does depend on as many several parts of the brain being then active, all such objections as were urged, on pp. 23, 57, and elsewhere, to the notion that 'parts' of consciousness _can_ 'combine' will be rejected as far-fetched, unreal, and 'metaphysical' by the atomistic philosopher. His 'purpose' is to gain a formula which shall unify things in a natural and easy manner, and for such a purpose the atomistic theory seems expressly made to his hand.

But the difficulty with the problem of 'correspondence' is not only that of solving it, it is that of even stating it in elementary terms.

"L'ombre en ce lieu s'amasse, et la nuit est la toute."

Before we can know just what sort of goings-on occur when thought corresponds to a change in the brain, we must know the _subjects_ of the goings-on. We must know which sort of mental fact and which sort of cerebral fact are, so to speak, in immediate juxtaposition. We must find the minimal mental fact whose being reposes directly on a brain-fact; and we must similarly find the minimal brain-event which can have a mental counterpart at all. Between the mental and the physical minima thus found there will be an immediate relation, the expression of which, if we had it, would be the elementary psycho-physic law.

Our own formula has escaped the metempiric assumption of psychic atoms by _taking the entire thought_ (even of a complex object) _as the minimum with which it deals on the mental_ side, and the entire brain as the minimum on the physical side. But the 'entire brain' is not a physical fact at all! It is nothing but our name for the way in which a billion of molecules arranged in certain positions may affect our sense. On the principles of the corpuscular or mechanical philosophy, the only realities are the separate molecules, or at most the cells. Their aggregation into a 'brain' is a fiction of popular speech. Such a figment cannot serve as the objectively real counterpart to any psychic state whatever. Only a genuinely physical fact can so serve, and the molecular fact is the only genuine physical fact. Whereupon we seem, if we are to have an elementary psycho-physic law at all, thrust right back upon something like the mental-atom-theory, for the molecular fact, being an element of the 'brain,' would seem naturally to correspond, not to total thoughts, but to elements of thoughts. Thus the real in psychics seems to 'correspond' to the unreal in physics, and _vice versa_; and our perplexity is extreme.

=The Relation of States of Mind to their 'Objects.'=--The perplexity is not diminished when we reflect upon our assumption that states of consciousness can _know_ (pp. 2-13). From the common-sense point of view (which is that of all the natural sciences) knowledge is an ultimate relation between two mutually external entities, the knower and the known. The world first exists, and then the states of mind; and these gain a cognizance of the world which gets gradually more and more complete. But it is hard to carry through this simple dualism, for idealistic reflections will intrude. Take the states of mind called pure sensations (so far as such may exist), that for example of _blue_, which we may get from looking into the zenith on a clear day. Is the blue a determination of the feeling itself, or of its 'object'? Shall we describe the experience as a quality of our feeling or as our feeling of a quality? Ordinary speech vacillates incessantly on this point. The ambiguous word 'content' has been recently invented instead of 'object,' to escape a decision; for 'content' suggests something not exactly out of the feeling, nor yet exactly identical with the feeling, since the latter remains suggested as the container or vessel. Yet of our feelings as vessels apart from their content we really have no clear notion whatever. The fact is that such an experience as _blue_, as it is immediately given, can only be called by some such neutral name as that of _phenomenon_. It does not _come_ to us _immediately_ as a relation between two realities, one mental and one physical. It is only when, still thinking of it as the _same_ blue (cf. p. 239), we trace relations between it and other things, that it doubles itself, so to speak, and develops in two directions; and, taken in connection with some associates, figures as a physical quality, whilst with others it figures as a feeling in the mind.

Our non-sensational, or conceptual, states of mind, on the other hand, seem to obey a different law. They present themselves immediately as referring beyond themselves. Although they also possess an immediately given 'content,' they have a 'fringe' beyond it (p. 168), and claim to 'represent' something else than it. The 'blue' we have just spoken of, for instance, was, substantively considered, a _word_; but it was a word with a _meaning_. The quality blue was the _object_ of the thought, the word was its _content_. The mental state, in short, was not self-sufficient as sensations are, but expressly pointed at something more in which it meant to terminate.

But the moment when, as in sensations, object and conscious state seem to be different ways of considering one and the same fact, it becomes hard to justify our denial that mental states consist of parts. The blue sky, considered physically, is a sum of mutually external parts; why is it not such a sum, when considered as a content of sensation?

The only result that is plain from all this is that the relations of the known and the knower are infinitely complicated, and that a genial, whole-hearted, popular-science way of formulating them will not suffice. The only possible path to understanding them lies through metaphysical subtlety; and Idealism and _Erkenntnisstheorie_ must say their say before the natural-science assumption that thoughts 'know' things grows clear.

=The changing character of consciousness= presents another puzzle. We first assumed conscious 'states' as the units with which psychology deals, and we said later that they were in constant change. Yet any state must have a certain duration to be _effective_ at all--a pain which lasted but a hundredth of a second would practically be no pain--and the question comes up, how long may a state last and still be treated as _one_ state? In time-perception for example, if the 'present' as known (the 'specious present,' as we called it) may be a dozen seconds long (p. 281), how long need the present as knower be? That is, what is the minimum duration of the consciousness in which those twelve seconds can be apprehended as just past, the minimum which can be called a 'state,' for such a cognitive purpose? Consciousness, as a process in time, offers the paradoxes which have been found in all continuous change. There are no 'states' in such a thing, any more than there are facets in a circle, or places where an arrow 'is' when it flies. The vertical raised upon the time-line on which (p. 285) we represented the past to be 'projected' at any given instant of memory, is only an ideal construction. Yet anything broader than that vertical _is_ not, for the _actual_ present is only the joint between the past and future and has no breadth of its own. Where everything is change and process, how can we talk of 'state'? Yet how can we do without 'states,' in describing what the vehicles of our knowledge seem to be?

=States of consciousness themselves are not verifiable facts.= But 'worse remains behind.' Neither common-sense, nor psychology so far as it has yet been written, has ever doubted that the states of consciousness which that science studies are immediate data of experience. 'Things' have been doubted, but thoughts and feelings have never been doubted. The outer world, but never the inner world, has been denied. Everyone assumes that we have direct introspective acquaintance with our thinking activity as such, with our consciousness as something inward and contrasted with the outer objects which it knows. Yet I must confess that for my part I cannot feel sure of this conclusion. Whenever I try to become sensible of my thinking activity as such, what I catch is some bodily fact, an impression coming from my brow, or head, or throat, or nose. It seems as if consciousness as an inner activity were rather a _postulate_ than a sensibly given fact, the postulate, namely, of a _knower_ as correlative to all this known; and as if '_scious_ness' might be a better word by which to describe it. But 'sciousness postulated as an hypothesis' is practically a very different thing from 'states of consciousness apprehended with infallible certainty by an inner sense.' For one thing, it throws the question of _who the knower really is_ wide open again, and makes the answer which we gave to it at the end of Chapter XII a mere provisional statement from a popular and prejudiced point of view.

=Conclusion.=--When, then, we talk of 'psychology as a natural science,' we must not assume that that means a sort of psychology that stands at last on solid ground. It means just the reverse; it means a psychology particularly fragile, and into which the waters of metaphysical criticism leak at every joint, a psychology all of whose elementary assumptions and data must be reconsidered in wider connections and translated into other terms. It is, in short, a phrase of diffidence, and not of arrogance; and it is indeed strange to hear people talk triumphantly of 'the New Psychology,' and write 'Histories of Psychology,' when into the real elements and forces which the word covers not the first glimpse of clear insight exists. A string of raw facts; a little gossip and wrangle about opinions; a little classification and generalization on the mere descriptive level; a strong prejudice that we _have_ states of mind, and that our brain conditions them: but not a single law in the sense in which physics shows us laws, not a single proposition from which any consequence can causally be deduced. We don't even know the terms between which the elementary laws would obtain if we had them (p. 464). This is no science, it is only the hope of a science. The matter of a science is with us. Something definite happens when to a certain brain-state a certain 'sciousness' corresponds. A genuine glimpse into what it is would be _the_ scientific achievement, before which all past achievements would pale. But at present psychology is in the condition of physics before Galileo and the laws of motion, of chemistry before Lavoisier and the notion that mass is preserved in all reactions. The Galileo and the Lavoisier of psychology will be famous men indeed when they come, as come they some day surely will, or past successes are no index to the future. When they do come, however, the necessities of the case will make them 'metaphysical.' Meanwhile the best way in which we can facilitate their advent is to understand how great is the darkness in which we grope, and never to forget that the natural-science assumptions with which we started are provisional and revisable things.

THE END.

INDEX.

Abstract ideas, 240, 25;
characters, 353;
propositions, 354

Abstraction, 251;
see _Distraction_

_Accommodation_, of crystalline lens, 32;
of ear, 49

Acquaintance, 14

Acquisitiveness, 407

Action, what holds attention determines, 448

After-images, 43-5

AGASSIZ, 132

Alexia, 113

ALLEN, GRANT, 104

Alternating personality, 205 ff.

AMIDON, 132

Analysis, 56, 248, 251, 362

Anger, 374

Aphasia, 108, 113;
loss of images in, 309

Apperception, 326

Aqueduct of Silvius, 80

Arachnoid membrane, 84

Arbor vitæ, 86

ARISTOTLE, 318

Articular sensibility, 74

Association, Chapter XVI;
the order of our ideas, 253;
determined by cerebral laws, 255;
is not of ideas, but of things thought of, 255;
the elementary principle of, 256;
the ultimate cause of is habit, 256;
indeterminateness of its results, 258;
total recall, 259;
partial recall and the law of interest, 261;
frequency, recency, vividness, and emotional congruity
tend to determine the object recalled, 264;
focalized recall or by similarity, 267, 364;
voluntary trains of thought, 271;
problems, 273

Atomistic theories of consciousness, 462

Attention, Chapter XIII;
its relation to interest, 170;
its physiological ground, 217;
narrowness of field of consciousness, 217;
to how many things possible, 219;
to simultaneous sight and sound, 220;
its varieties, 220;
voluntary, 224;
involuntary, 220;
change necessary to, 226;
its relation to genius, 227;
physiological conditions of, 228;
the sense-organ must be adapted, 229;
the idea of the object must be aroused, 232;
pedagogic remarks, 236;
attention and free-will, 237;
what holds attention determines action, 448;
volitional effort is effort of attention, 450

Auditory centre in brain, 113

Auditory type of imagination, 306

AUSTEN, Miss, 261

Automaton theory, 10, 101

AZAM, 210

BAHNSEN, 147

BAIN, 145, 367, 370

BERKLEV, 302, 303, 347

BINET, 318, 332

Black, 45-6

Blind Spot, 31

BLIX, 64, 68

Blood-supply, cerebral, 130

Bodily expression, cause of emotions, 375

BRACE, JULIA, 252

Brain, the functions of, Chapter VIII, 91

_Brain_, its connection with mind, 5-7;
its relations to outer forces, 9;
relations of consciousness to, 462

Brain, structure of, Chapter VII, 78 ff.;
vesicles, 78 ff.;
dissection of sheep's, 81;
how to preserve, 83;
functions of, Chapter VIII, 91 ff.

BRIDGMAN, LAURA, 252, 308

BROCA, 109, 113, 115

Broca's convolution, 109

BRODHUN, 46

BROOKS, Prof. W. K., 412

Brutes, reasoning of, 367

Calamus scriptorius, 84

_Canals_, semicircular, 50

CARPENTER, 223, 224

CATTELL, 125, 126, 127

Caudate nucleus, 81, 86

Centres, nerve, 92

Cerebellum, its relation to equilibrium, 76;
its anatomy, 79, 84

Cerebral laws, of association, 255

Cerebral process, see _Neural Process_

Cerebrum, see _Brain_, _Hemisphere_

Changing character of consciousness, 152, 466

CHARCOT, 113, 309

Choice, see _Interest_

Coalescence of different sensations into the same 'thing,' 339

_Cochlea_, 51, 52

Cognition, see _Reasoning_

Cold, sensations of, 63 ff.;
nerves of, 64

_Color_, 40-3

Commissures, 84

Commissure, middle, 88 ff.;
anterior, 88;
posterior, 88

Comparison of magnitudes, 342

_Compounding_ of sensations, 23, 43, 57

Compound objects, analysis of, 248

Concatenated acts, dependent on habit, 140

Conceiving, mode of, what is meant by, 354

Conceptions, Chapter XIV;
defined, 239;
their permanence, 239;
different states of mind can mean the same, 239;
abstract, universal, and problematic, 240;
the thought of 'the same' is not the same thought over again, 243

Conceptual order different from perceptual, 243

Consciousness, stream of, Chapter XI, 151;
four characters in, 152;
personal, 152;
is in constant change, 152, 466;
same state of mind never occurs twice, 154;
consciousness is continuous, 157;
substantive and transitive states of, 160;
interested in one part of its object more than another, 170;
double consciousness, 206 ff.;
narrowness of field of, 217;
relations of to brain, 462

Consciousness and Movement, Chapter XXIII;
all consciousness is motor, 370

Concomitants, law of varying, 251

Consent, in willing, 452

Continuity of object of consciousness, 157

_Contrast_, 25, 44-5

_Convergence_ of eyeballs, 31, 33

Convolutions, motor, 106

Corpora fimbriata, 86

Corpora quadrigemma, 79, 86, 89

Corpus albicans, 84

Corpus callosum, 81, 84

Corpus striatum, 81, 86, 108

_Cortex_, 11, note

Cortex, localization in, 104;
motor region of, 106

_Corti's_ organ, 52

Cramming, 295

Crura of brain, 79, 84, 108

Curiosity, 407

Currents, in nerves, 10

CZERMAK, 70

DARWIN, 388, 389

Deafness, mental, 113

DELAGE, 76

Deliberation, 448

Delusions of insane, 207

Dermal senses, 60 ff.

Determinism and psychology, 461

Decision, five types, 429

Differences, 24;
directly felt, 245;
not resolvable into composition, 245;
inferred, 248

Diffusion of movements, the law of, 371

Dimension, third, 342, 346

Discharge, nervous, 120

Discord, 58

Discrimination, Chapter XV, 59;
touch, 62;
defined, 244;
conditions which favor, 245;
sensation of difference, 246;
differences inferred, 248;
analysis of compound objects, 249;
to be easily singled out a quality should already be
separately known, 250;
dissociation by varying concomitants, 251;
practice improves discrimination, 252;
of space, 338
See _Difference_

'Disparate' retinal points, 35

Dissection, of sheep's brain, 81

_Distance_, as seen, 39;
between members of series, 24;
in space, see _Third dimension_

Distraction, 218 ff.

Division of space, 338

DONALDSON, 64

Double consciousness, 206 ff.

Double images, 36

Double personality, 205

Duality of brain, 205

DUMONT, 135

Dura mater, 82

Duration, the primitive object in time-perception, 280;
our estimation of short, 281

Ear, 47 ff.

Effort, feeling of, 434;
feels like an original force, 442;
volitional effort is effort of attention, 450;
ethical importance of the phenomena of effort, 458

Ego, see _Self_

Embryological sketch, Chapter VII, 78

Emotion, Chapter XXIV;
compared with instincts, 373;
varieties of, innumerable, 374;
causes of varieties, 375, 381;
results from bodily expression, 375;
this view not materialistic, 380;
the subtler emotions, 384;
fear, 385;
genesis of reactions, 388

Emotional congruity, determines association, 264

Empirical self, see _Self_

Emulation, 406

End-organs, 10;
of touch, 60;
of temperature, 64;
of pressure, 60;
of pain, 67

Environment, 3

Essence of reason, always for subjective interest, 358

Essential characters, in reason, 354

Ethical importance of effort, 458

Exaggerated impulsion, causes an explosive will, 439

EXNER, 123, 281

Experience, 218, 244

Explosive will, from defective inhibition, 437;
from exaggerated impulsion, 439

Expression, bodily, cause of emotions, 375

Extensity, primitive to all sensation, 335

Exteriority of objects, 15

External world, 15

Extirpation of higher nerve-centres, 95 ff.

Eye, its anatomy, 28-30

Familiarity, sense of, see _Recognition_

Fear, 385, 406, 407

FECHNER, 21, 229

Feeling of effort, 434

FÉRÉ, 311

FERRIER, 132

Fissure of Rolando, seat of motor incitations, 106

Fissure of Sylvius, 108

Foramen of Monro, 88

Force, original, effort feels like, 442

Forgetting, 300

Fornix, 81, 86, 87, 89

Fovea centralis, 31

FRANKLIN, 121

FRANZ, Dr., 308

Freedom of the will, 237

Free-will and attention, 237;
relates solely to effort of attention, 455;
insoluble on strictly psychologic grounds, 456;
ethical importance of the phenomena of effort, 458

Frequency, determines association, 264

"Fringes" of mental objects, 163 ff.

Frogs' lower centres, 95

Functions of the Brain, Chapter VIII, 91;
nervous functions, general idea of, 91

Fusion of mental states, 197, 245, 339

Fusion, of sensations, 23, 43, 57

GALTON, 126, 265, 303, 306

Genius, 227, 327

GOETHE, 146, 157

GOLDSCHEIDER, 11, 64, 68

GOLTZ, 100

GUITEAU, 185

GURNEY, EDMUND, 331, 334

Habit, Chapter X, 134 ff.;
has a physical basis, 134;
due to plasticity, 135;
due to pathways through nerve-centres, 136;
effects of, 138;
practical use of, 138;
depends on sensations not attended to, 141;
ethical and pedagogical importance of 142 ff.;
habit the ultimate cause of association, 256

HAGENAUER, 386

HALL, ROBERT, 223

Hallucinations, 330 ff.

HAMILTON, 260, 268

Harmony, 58

HARTLEY, 255

Hearing, 47 ff.;
centre of, in cortex, 113

Heat-sensations, 63 ff.;
nerves of, 64

HELMHOLTZ, 26, 42, 43, 55, 56, 58, 121, 226, 227, 231, 233, 234, 321

Hemispheres, general notion of, 97;
chief seat of memory, 98;
effects of deprivation of, on frogs, 92;
on pigeons, 96

HERBART, 222, 326

HERBARTIAN SCHOOL, 157

HERING, 24, 26

HERZEN, 123, 124

HIPPOCAMPI, 88

HODGSON, 262, 264, 280, 283

HOLBROOK, 297

HORSLEY, 107, 118

HUME, 161, 244

Hunger, sensations of, 69

HUXLEY, 143

Hypnotic conditions, 301

Ideas, the theory of, 154 ff.;
never come twice the same, 154;
they do not permanently exist, 157;
abstract ideas, 240, 251;
universal 240;
order of ideas by association, 253

'Identical retinal points,' 35

Identity, personal, 201;
mutations of, 205 ff.;
alternating personality, 205

Ideo-motor action the type of all volition, 432

Illusions, 317 ff., 330

Images, mental, compared with sensations, 14;
double, in vision, 36;
'after-images,' 43-5;
visual, 302;
auditory, 306;
motor, 307;
tactile, 308

Imagination, Chapter XIX;
defined, 302;
differs in individuals, 302;
Galton's statistics of, 302;
visual, 302;
auditory, 306;
motor, 307;
tactile, 308;
pathological
differences, 308;
cerebral process of, 310;
not locally distinct from that of sensation, 310

Imitation, 406

Inattention, 218, 236

Increase of stimulus, 20;
serial, 24

Infundibulum, 82, 84, 88

Inhibition, defective, causes an Explosive Will, 437

Inhibition of instincts by habits, 399

Insane delusions, 207

Instinct, Chapter XXV;
emotions compared with, 373;
definition of, 391;
every instinct is an impulse, 392;
not always blind or invariable, 395;
modified by experience, 396;
two principles of non-uniformity, 398;
man has more than beasts, 398, 406;
transitory, 402;
of children, 406;
fear, 407

Intellect, part played by, in space-perception, 349

Intensity of sensations, 16

Interest, selects certain objects and determines thoughts 170;
influence in association, 262

Introspection, 118

JANET, 211, 212, 301

JACKSON, HUGHLINGS, 105, 117

Joints, their sensibility, 74

KADINSKY, 330

Knowledge, theory of, 2, 464, 467;
two kinds of, 14

KÖNIG, 46

KRISHABER, 208

Labyrinth, 47, 49-52

LANGE, K., 329

Laws, cerebral, of association, 255

Law, Weber's, 17;
--, Fechner's 21;
--, of relativity, 24

LAZARUS, 300, 323

Lenticular nucleus, 81

LEWES, 11, 232, 326

Likeness, 243, 364

LINDSAY, Dr., 413

Localization of Functions in the hemispheres, 104 ff.

Localization, Skin, 61

Locations, in environment, 340;
serial order of, 341

LOCKE, 244, 302, 357

LOCKEAN SCHOOL, 157

Locomotion, instinct of, 406

LOMBARD, 131

Longituditional fissure, 84

LOTZE, 175

Love, 407

Lower Centres, of frogs and pigeons, 95 ff.

LUDWIG, 130

MACH, 75

Mamillary bodies, 84

Man's intellectual distinction from brutes, 367

MANTEGAZZA, 390

MARTIN, 40, 44, 45, 49, 52, 53, 60, 61, 65, 69

MARTINEAU, 251

Materialism and emotion, 380

MATTEUCI, 120

MAUDSLEY, 138

Measurement, of sensations, 22;
of space, 342

'Mediumships,' 212

Medulla oblongata, 84, 108

Memory, Chapter XVIII;
hemispheres physical seat of, 98;
defined, 287;
analysis of the phenomenon of memory, 287 ff.;
return of a mental image is not memory, 289;
association explains recall and retention, 289;
brain-scheme of, 291;
conditions of good memory, 292;
multiple associations favor, 294;
effects of cramming on, 295;
how to improve memory, 298;
recognition, 299;
forgetting, 300;
hypnotics, 301

Mental blindness, 112

Mental images, 14

Mental operations, simultaneous, 219

Mental states, cannot fuse, 197;
relation of, to their objects, 464

MERKEL, 59, 66

Metaphysics, what the word means, 461

MEYER, G. H., 308, 311

MEYNERT, 105, 117

MILL, JAMES, 196, 276, 289

MILL, J. S., 147, 157

Mimicry, 406

Mind depends on brain conditions, 3-7;
states of, their relation to their objects, 464;
see _Consciousness_

Modesty, 407

Monistic theories of consciousness, 462

MORGAN, LLOYD, 368

MOSSO, 130, 131

Motion, sensations of, Chapter VI, 70 ff.;
feeling of motion over surfaces, 70

Motor aphasia, 108

Motor region of cortex, 106

Motor type of imagination, 307

Movement, consciousness and, II, Chapter I;
images of movement, 307;
all consciousness is motor, 370

MUNK, 110

MÜNSTERBERG, 23, 311

Muscular sensation, 65 ff.;
relations to space, 66, 74;
muscular centre in cortex, 106

MUSSEY, DR., 440

NAUNYN, 115

_Nerve-currents_, 9

Nervous discharge, 120

Nerve-endings in the skin, 60;
in muscles and tendons, 66-67;
Pain, 67 ff.;
nerve-centres, 92

Nerves, general functions of, 91 ff.

Neural activity, general conditions of, Chapter IX, 120;
nervous discharge, 120

Neural functions, general idea of, 91

Neural process, in habit, 134 ff.;
in association, 255 ff.;
in memory, 291;
in imagination, 310;
in perception, 329

Nucleus lenticularis, 81, 108;
caudatus, 81, 108

Object, the, of sensation, 13-15;
of thought, 154, 163;
one part of, more interesting than another, 170;
object must change to hold attention, 226;
objects as signs and as realities, 345;
relation of states of mind to their object, 464

Occipitel lobes, seat of visual centre, 110

Old-fogyism vs. genius, 327

Olfactory lobes, 82, 84

Olivary bodies, 85

Optic nerve, 82, 89

Optic tracts, 84

Original force, effort feels like one, 442

Overtones, 55

Pain, 67 ff.;
pain and pleasure as springs of action, 444

PASCAL, 223

Past time, known in a present feeling, 285;
the immediate past is a portion of the present duration-block, 280

PAULHAN, 219, 220

Pedagogic remarks on habit, 142;
on attention, 236

Peduncles, 84, 85, 86

Perception, Chapter XX;
compared with sensation, 312;
involves reproductive processes, 312;
the perceptive state of mind is not a compound, 313;
perception is of definite and probable things, 316;
illusory perceptions, 317;
physiological process of perception, 329

Perception of Space, Chapter XXI

PEREZ, M., 408

Personal Identity, 201;
mutations of, 205 ff.;
alternating personality, 205 ff.

Personality, alterations of, 205 ff.

Philosophy, Psychology and, Epilogue, 461

Phosphorus and thought, 132

Pia mater, 82

Pigeons' lower centres, 96

Pitch, 54

Pituitary body, 82, 89

Place, a series of positions, 341

Plasticity, as basis of habit, defined, 135

PLATO, 240

Play, 407

Pleasure, and pain, as springs of action, 444

Psychology and Philosophy, Epilogue, 461

Pons Varolii, 79, 84, 108

Positions, place a series of, 341

Practice, improves discrimination, 252

Present, the present moment, 280

Pressure sense, 60

PREYER, 406

Probability determines what object shall be perceived, 316, 329

Problematic conceptions, 240

Problems, solution of, 272

Projection of sensations, eccentric, 15

Psychology, defined, 1;
a natural science, 2;
what data it assumes, 2;
Psychology and Philosophy, Chapter XXVII

Psycho-physic law, 17, 24, 46, 59, 66, 67

Pugnacity, 406

PURKINJE, 75

Pyramids, 85

Quality, 13, 23, 25, 56

Raehlmann, 349

Rationality, 173

Reaction-time, 120 ff.

Real magnitude, determined by æsthetic and practical interests, 344

Real space, 337

Reason, 254

Reasoning, Chapter XXIII;
what it is, 351;
involves use of abstract characters, 353;
what is meant by an essential character, 354;
the essence is always for a subjective interest, 358;
two great points in reasoning, 360;
sagacity, 362;
help from association by similarity, 364;
reasoning power of brutes, 367

Recall, 289

Recency, determines association, 264

'Recepts,' 368

Recognition, 299

Recollection, 289 ff.

Redintegration, 264

Reflex acts, defined, 92;
reaction-time measures one, 123;
concatenated habits are constituted by a chain of, 140

REID, 313

Relations, between objects, 162;
feelings of, 162

'_Relativity_ of knowledge,' 24

Reproduction in memory, 289 ff.;
voluntary, 271

Resemblance, 243

Retention in memory, 289

Retentiveness, organic, 291;
it is unchangeable, 296

Retina, peripheral parts of, act as sentinels, 73

Revival in memory, 289 ff.

RIBOT, 300

RICHET, 410

Rivalry of selves, 186

ROBERTSON, Prof. CROOM, 318

Rolando, fissure of, 106

ROMANES, 128, 322, 367

ROSENTHAL, 11

ROUSSEAU, 148

Rotation, sense of, 75

Sagacity, 362

Sameness, 201, 202

SCHAEFER, 107, 110, 118

SCHIFF, 131

SCHNEIDER, 72, 372, 392

_Science_, natural, 1

SCOTT, Prof., 311

Sea-sickness, accidental origin, 390

Seat of consciousness, 5

Selection, 10;
a cardinal function of consciousness, 170

Self, The, Chapter XII;
not primary, 176;
the empirical self, 176;
its constituents, 177;
the material self, 177;

the social self, 179;
the spiritual self, 181;
self-appreciation, 182;
self-seeking, bodily, social, and spiritual, 184;
rivalry of the mes. 186;
their hierarchy, 190;
teleology of self-interest, 193;
the I, or 'pure ego,' 195;
thoughts are not compounded of 'fused' sensations, 196;
the soul as a combining medium, 200;
the sense of personal identity, 201;
explained by identity of function in successive passing thoughts, 203;
mutations of the self, 205;
insane delusions, 207;
alternating personalities, 210;
medium-ships, 212;
who is the thinker? 215

Self-appreciation, 182

Self-interest, theological uses of, 193;
teleological character of, 193

Selves, their rivalry, 186

Semicircular canals, 50

Semicircular canals, their relation to sensations of rotation, 75

Sensations, in General, Chapter II, p. 9;
distinguished from perceptions, 12;
from images, 14;
_first_ things in consciousness, 12;
make us acquainted with qualities, 14;
their exteriority, 15;
intensity of sensations, 16;
their measurement, 21;
they are not compounds, 23

Sensations, of touch, 60;
of skin, 60 ff.;
of smell, 69;
of pain, 67;
of heat, 63;
of cold, 63;
of hunger, 69;
of thirst, 69;
of motion, 70;
muscular, 65;
of taste, 69;
of pressure, 60;
of joints, 74;
of movement through space, 75;
of rotation, 75;
of translation, 76

Sense of time, see _Time_

Sensory centres in the cortex, 113 ff.

Septum lucidum, 87

Serial order of locations, 341

Shame, 374

Sheep's brain, dissection of, 81

Sight, 28 ff.;
see _Vision_

Signs, 40;
sensations are, to us of other sensations, whose
space-value is held to be more real, 345 ff.

Similarity, association by, 267, 364;
see _Likeness_

Size, 40

Skin--senses, 60 ff.;
localizing power of, 61;
discrimination of points on, 247

Smell, 69;
centre of, in cortex, 116

SMITH, T. C., 311

Sociability, 407

Soul, the, as ego or thinker, 196;
as a combining medium, 200, 203

Sound, 53-59;
images of, 306

Space, Perception of, Chapter XXI;
extensity in three dimensions primitive to all sensation, 335;
construction of real space, 337;
the processes which it involves: (1) Subdivision, 338;
(2) Coalescence of different sensible data into one 'thing,' 339;
(3) Location in an environment, 342;
objects which are signs, and objects which are realities, 345;
the third dimension, 346;
Berkeley's theory of distance, 346;
part played by intellect in space-perception, 349

Space, relation of muscular sense to, 66, 74

SPALDING, 401 ff.

Span of consciousness, 219, 286

Specific energies, 11

Speech, centres of, in cortex, 109;
thought possible without it, 169;
see _Aphasia_

SPENCER, 103, 387, 390

Spinal cord, conduction of pain by, 68;
centre of defensive movements, 93

Spiritual substance, see _Soul_

Spiritualistic theories of consciousness, 462

Spontaneous trains of thought, 257;
examples, 257 ff., 271

STARR, 107, 113, 115

STEINTHAL, 327

Stream of Consciousness, Chapter XI, 151

STRICKER, 307

Subdivision of space, 338

Substantive states of mind, 160

Succession _vs._ duration, 280;
not known by successive feelings, 285

Summation of stimuli, 128

Surfaces, feeling of motion over, 70

Tactile centre in cortex, 116

Tactile images, 308

TAINE, 208

Taste, 69;
centre of, in cortex, 116

Teleological character of consciousness, 4;
of self-interest, 193

Temperature-sense, 63 ff.

Terminal organs, 10, 30, 52

Thalami, 80, 86, 89, 108

Thermometry, cerebral, 131

'Thing,' coalescence of sensations to form the same, 339

Thinking principle, see _Soul_

Third dimension of space, 346

Thirst, sensations of, 69

THOMSON, Dr. ALLEN, 129

Thought, the 'Topic' of, 167;
stream of, 151;
can be carried on in any terms, 167;
unity of, 196;
spontaneous trains of, 257;
the entire thought the minimum, 464

'Timbre,' 55

Time, sense of, Chapter XVII;
begins with duration, 280;
no sense of empty time, 281;
compared with perception of space, 282;
discrete flow of time, 282;
long intervals conceived symbolically, 283;
we measure duration by events that succeed in it, 283;
variations in our estimations of its length, 283;
cerebral processes of, 286

Touch, 60 ff.;
centre of, in cortex, 116;
images of, 308

Transcendental self or ego, 196

Transitive states of mind, 160

Translation, sense of, 76

Trapezium, 85

TURNER, Dr. J. E., 440

Tympanum, 48

Types of decision, 429

Unity of the passing thought, 196

Universal conceptions, 240

URBANTSCHITCH, 25

Valve of Vieussens, 80, 86

Variability of the emotions, 381

Varying concomitants, law of disassociation by, 251

Ventricles, 79 ff.

VIERORDT, 71

Vision, 28 ff.;
binocular, 33-9;
of solidity, 37

Visual centre of cortex, 110, 115

Visual imagination, 302

Visualizing power, 302

Vividness, determines association, 264

Volition, see _Will_

VOLKMANN, 285

Voluminousness, primitive, of sensations, 335

Voluntary acts, defined, 92;
voluntary attention, 224;
voluntary trains of thought, 271

Weber's law, 17, 24, 46, 59

Weber's law--weight, 66;
pain, 67

Weight, sensibility to, 66 ff.

WERNICKE, 109, 113, 115

WESLEY, 223

WHEATSTONE, 347

WIGAN, 300

Will, Chapter XXVI;
voluntary acts, 415;
they are secondary performances, 415;
no third kind of idea is called for, 418;
the motor-cue, 420;
ideo-motor action, 432;
action after deliberation, 428;
five types of decision, 429;
feeling of effort, 434;
healthiness of will, 435;
defects of, 436;
the explosive will: (1) from defective inhibition, 437;
(2) from exaggerated impulsion, 439;
the obstructed will, 441;
effort feels like an original force, 442;
pleasure and pain as springs of action, 444;
what holds attention determines action, 448;
will is a relation between the mind and its ideas, 449;
volitional effort is effort of attention, 450;
free-will, 455;
ethical importance of effort, 458

Willing terminates with the prevalence of the idea, 449

WUNDT, 11, 18, 25, 58, 122, 123, 125, 127, 220, 281

FOOTNOTES:

[1] In the present volume I have given so much extension to the details of 'Sensation' that I have obeyed custom and put that subject first, although by no means persuaded that such order intrinsically is the best. I feel now (when it is too late for the change to be made) that the chapters on the Production of Motion, on Instinct, and on Emotion ought, for purposes of teaching, to follow immediately upon that on Habit, and that the chapter on Reasoning ought to come in very early, perhaps immediately after that upon the Self. I advise teachers to adopt this modified order, in spite of the fact that with the change of place of 'Reasoning' there ought properly to go a slight amount of re-writing.

[2] The subject may feel _pain_, however, in this experiment; and it must be admitted that nerve-fibres of every description, terminal organs as well, are to some degree excitable by mechanical violence and by the electric current.

[3] Thus the optic nerve-fibres are traced to the occipital lobes, the olfactory tracts go to the lower part of the temporal lobe (hippocampal convolution), the auditory nerve-fibres pass first to the cerebellum, and probably from thence to the upper part of the temporal lobe. These anatomical terms used in this chapter will be explained later. The _cortex_ is the gray surface of the convolutions.

[4] Vorlesungen über Menschen u. Thierseele, Lecture VII.

[5] In other words, _S_ standing for the sensation in general, and _d_ for its noticeable increment, we have the equation _d__S_ = const. The increment of stimulus which produces _d__S_ (call it _d__R_) meanwhile varies. Fechner calls it the 'differential threshold'; and as its _relative_ value to _R_ is always the same, we have the equation _d__R_/_R_ = const.

[6] Beiträge zur exp. Psychol., Heft 3, p. 4.

[7] I borrow it from Ziehen: Leitfaden d. Physiologischen Psychologie, 1891, p. 36, who quotes Hering's version of it.

[8] Successive ones also; but I consider simultaneous ones only, for simplicity's sake.

[9] The extreme case is where green light and red, _e.g._ light falling simultaneously on the retina, give a sensation of yellow. But I abstract from this because it is not certain that the incoming currents here affect different fibres of the optic nerve.

[10] The student can easily verify the coarser features of the eye's anatomy upon a bullock's eye, which any butcher will furnish. Clean it first from fat and muscles and study its shape, etc., and then (following Golding Bird's method) make an incision with a pointed scalpel into the sclerotic half an inch from the edge of the cornea, so that the black choroid membrane comes into view. Next with one blade of a pair of scissors inserted into this aperature, cut through sclerotic, choroid, and retina (avoid wounding the membrane of the vitreous body!) all round the eyeball parallel to the cornea's edge.

The eyeball is thus divided into two parts, the anterior one containing the iris, lens, vitreous body, etc., whilst the posterior one contains most of the retina. The two parts can be separated by immersing the eyeball in water, cornea downwards, and simply pulling off the portion to which the optic nerve is attached. Floating this detached posterior cap in water, the delicate retina will be seen spread out over the choroid (which is partly iridescent in the ox tribe); and by turning the cup inside out, and working under water with a camel's-hair brush, the vessels and nerves of the eyeball may be detected.

The anterior part of the eyeball can then be attacked. Seize with forceps on each side the edge of the sclerotic and choroid (not including the retina), raise the eye with the forceps thus applied and shake it gently till the vitreous body, lens, capsule, ligament, etc., drop out by their weight, and separate from the iris, ciliary processes, cornea, and sclerotic, which remains in the forceps. Examine these latter parts, and get a view of the ciliary muscle which appears as a white line, when with camel's-hair brush and scalpel the choroid membrane is detached from the sclerotic as far forward as it will go. Turning to the parts that cling to the vitreous body observe the clear ring around the lens, and radiating outside of it the marks made by the ciliary processes before they were torn away from its suspensory ligament. A fine capillary tube may now be used to insufflate the clear ring, just below the letter _p_ in Fig. 3, and thus to reveal the suspensory ligament itself.

All these parts can be seen in section in a frozen eye or one hardened in alcohol.

[11] This vertical partition is introduced into stereoscopes, which otherwise would give us three pictures instead of one.

[12] The simplest form of stereoscope is two tin tubes about one and one-half inches calibre, dead black inside and (for normal eyes) ten inches long. Close each end with paper not too opaque, on which an inch-long thick black line is drawn. The tubes can be looked through, one by each eye, and held either parallel or with their farther ends converging. When properly rotated, their images will show every variety of fusion and non-fusion, and stereoscopic effect.

[13] Martin: The Human Body, p. 530.

[14] Ibid.

[15] The ordinary mixing of _pigments_ is not an addition, but rather, as Helmholtz has shown, a subtraction, of lights. To _add_ one color to another we must either by appropriate glasses throw differently colored beams upon the same reflecting surface; or we must let the eye look at one color through an inclined plate of glass beneath which it lies, whilst the upper surface of the glass reflects into the same eye another color placed alongside--the two lights then mix on the retina; or, finally, we must let the differently colored lights fall in succession upon the retina, so fast that the second is there before the impression made by the first has died away. This is best done by looking at a rapidly rotating disk whose sectors are of the several colors to be mixed.

[16] Martin: _op. cit._

[17] Martin, pp. 525-8.

[18] In teaching the anatomy of the ear, great assistance will be yielded by the admirable model made by Dr. Auzoux, 56 Rue de Vaugirard, Paris, described in the catalogue of the firm as "No. 21--_Oreille, temporal de_ 60 cm., nouvelle édition," etc.

[19] This description is abridged from Martin's 'Human Body'.

[20] Martin: _op. cit._

[21] Martin: _op. cit._

[22] Martin: _op. cit._

[23] Martin: _op. cit._

[24] Martin: _op. cit._

[25] Martin: _op. cit._, with omissions.

[26] Martin: _op. cit._

[27] Vierteljahrsch. für wiss. Philos., II. 377.

[28] This chapter will be understood as a mere sketch for beginners. Models will be found of assistance. The best is the 'Cerveau de Texture de Grande Dimension,' made by Auzoux, 56 Rue de Vaugirard, Paris. It is a wonderful work of art, and costs 300 francs. M. Jules Talrich of No. 97 Boulevard Saint-Germain, Paris, makes a series of five large plaster models, which I have found very useful for class-room purposes. They cost 350 francs, and are far better than any German models which I have seen.

[29] All the places in the brain at which the cavities come through are filled in during life by prolongations of the membrane called _pia mater_, carrying rich plexuses of blood-vessels in their folds.

[30] The Physiology of Mind, p. 155.

[31] J. Bahnsen: 'Beiträge zu Charakterologie' (1867), vol. I. p. 209.

[32] De l'Intelligence, 3me édition (1878), vol. II. p. 461, note.

[33] Some of the evidence for this medium's supernormal powers is given in The Proceedings of the Society for Psychical Research, vol. VI. p. 436, and in the last Part of vol. VII. (1892).

[34] Mental Physiol., § 124. The oft-cited case of soldiers in battle not perceiving that they are wounded is of an analogous sort.

[35] Physiol. Optik, p. 741.

[36] I refer to a recency of a few hours. Mr. Galton found that experiences from boyhood and youth were more likely to be suggested by words seen at random than experiences of later years. See his highly interesting account of experiments in his Inquiries into Human Faculty, pp. 191-203.

[37] Miss M. W. Calkins (Philosophical Review, I. 389, 1892) points out that the persistent feature of the going thought, on which the association in cases of similarity hinges, is by no means always so slight as to warrant the term 'focalized.' "If the sight of the whole breakfast-room be followed by the visual image of yesterday's breakfast-table, with the same setting and in the same surroundings, the association is practically total," and yet the case is one of similarity. For Miss Calkins, accordingly, the more important distinction is that between what she calls _desistent_ and _persistent_ association. In 'desistent' association all parts of the going thought fade out and are replaced. In 'persistent' association some of them remain, and form a bond of similarity between the mind's successive objects; but only where this bond is extremely delicate (as in the case of an abstract relation or quality) is there need to call the persistent process 'focalized.' I must concede the justice of Miss Calkins's criticism, and think her new pair of terms a useful contribution. Wundt's division of associations into the two classes of _external_ and _internal_ is congruent with Miss Calkins's division. Things associated internally must have some element in common; and Miss Calkins's word 'persistent' suggests how this may cerebrally come to pass. 'Desistent,' on the other hand, suggests the process by which the successive ideas become external to each other or preserve no inner tie.

[38] A common figure-alphabet is this:

1 2 3 4 5 6 7 8 9 0
t n m r l sh g f b s
d j k v p c
ch c z
g qu

[39] In Mind, IX. 206, M. Binet points out the fact that what is fallaciously inferred is always an object of some other sense than the 'this.' 'Optical illusions' are generally errors of touch and muscular sensibility, and the fallaciously perceived object and the experiences which correct it are both tactile in these cases.

[40] Romanes, Mental Evolution in Animals, p. 324.

[41] M. Lazarus: Das Leben d. Seele (1857), II. p. 32. In the ordinary hearing of speech half the words we seem to hear are supplied out of our own head. A language with which we are familiar is understood even when spoken in low tones and far off. An unfamiliar language is unintelligible under these conditions. The 'ideas' for interpreting the sounds by not being ready-made in our minds, as they are in our familiar mother-tongue, do not start up at so faint a cue.

[42] Einleitung in die Psychologie u. Sprachwissenschaft (1881), p. 171.

[43] The great maxim in pedagogy is to knit every new piece of knowledge on to a preëxisting curiosity--i.e., to assimilate its matter in some way to what is already known. Hence the advantage of "comparing all that is far off and foreign to something that is near home, of making the unknown plain by the example of the known, and of connecting all the instruction with the personal experience of the pupil.... If the teacher is to explain the distance of the sun from the earth, let him ask ... 'If anyone there in the sun fired off a cannon straight at you, what should you do?' 'Get out of the way,' would be the answer. 'No need of that,' the teacher might reply. 'You may quietly go to sleep in your room, and get up again, you may wait till your confirmation-day, you may learn a trade, and grow as old as I am,--_then_ only will the cannon-ball be getting near, _then_ you may jump to one side! See, so great as that is the sun's distance!'" (K. Lange, Ueber Apperception, 1879, p. 76.)

[44] The writer of the present work is Agent of the Census for America, and will thankfully receive accounts of cases of hallucination of vision, hearing, etc., of which the reader may have knowledge.

[45] Cf. Raehlmann in Zeitschrift für Psychol. und Physiol. der Sinnesorgane, II. 79.

[46] Readers brought up on Popular Science may think that the molecular structure of things is their real essence in an absolute sense, and that water is H-O-H more deeply and truly than it is a solvent of sugar or a slaker of thirst. Not a whit! It is _all_ of these things with equal reality, and the only reason why _for the chemist_ it is H-O-H primarily, and only secondarily the other things, is that _for his purpose_ of laboratory analysis and synthesis, and inclusion in the science which treats of compositions and decompositions, the H-O-H aspect of it is the more important one to bear in mind.

[47] Mental Evolution in Man, p. 74.

[48] Origin of the Emotions (N. Y. ed.), p. 292.

[49] Spalding, Macmillan's Magazine, Feb. 1873, p. 287.

[50] _Ibid._, p. 289.

[51] Psychologie de l'Enfant, p. 72.

[52] Der Menschliche Wille, p. 224.

[53] Deutsches Archiv f. Klin. Medicin, xxii. 321.

[54] Medicinische Psychologie, p. 293.

[55] This _volitional_ effort pure and simple must be carefully distinguished from the _muscular_ effort with which it is usually confounded. The latter consists of all those peripheral feelings to which a muscular 'exertion' may give rise. These feelings, whenever they are massive and the body is not 'fresh,' are rather disagreeable, especially when accompanied by stopped breath, congested head, bruised skin of fingers, toes, or shoulders, and strained joints. And it is only _as thus disagreeable_ that the mind must make its _volitional_ effort in stably representing their reality and consequently bringing it about. That they happen to be made real by muscular activity is a purely accidental circumstance. There are instances where the fiat demands great volitional effort though the muscular exertion be insignificant, e.g. the getting out of bed and bathing one's self on a cold morning. Again, a soldier standing still to be fired at expects disagreeable sensations from his muscular passivity. The action of his will, in sustaining the expectation, is identical with that required for a painful muscular effort. What is hard for both is _facing an idea as real_.