spectively. 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? Or. dinary 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 nam 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 con

scious 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, popularscience 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.

៩

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 be

tween 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?

6

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 'sciousness' 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 cer, tainty 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