and contact being related to one another, as are the sensations, say, of blue, We may approach the matter in another way, and say

red and green. that sense material as such forms a poor basis of division. Various factors must be allowed for, as familiarity, quantity of detail, after-sensations and after-images, strain, connection with sense organs, movements involved, ease and continuousness of apprehension, and the like (sec. 120). [Experiment with the several senses.] If we do that, it will be seen that there is at least a prima facie case for denying that the sense material differs much, even when hearing is contrasted with seeing. Probably if we could alter the factors referred to, we might be unable to tell which is a sound sensation and which a sight sensation. Once more, then, we find reason to think that the sense material offers no barriers to a unitary view of things.

In this section I have only attempted to show that a simplified view of things is possible which shall embrace all our acquisitions in one graduated scheme. There is no attempt here to account for the differences; but only to show that there are no violent breaks and no deep chasms in the world as given. In the concrete the difference between blue and yellow is as final as that between blue and sweet.

There is one striking fact which we observe exclusively in primary systems. To illustrate, the primary and the secondary views of a boy at a given moment may be said to be alike; yet under favourable circumstances the image of the boy will remain unchanged after twenty years, while the sensation after that period shows some one tall and broad and bearded. In the image, assuming no active interference, wear alone is observable, while the size, shape and colour have not changed except through fading. [Analyse some instance.] Theoretically, secondary systems or images may change as sensations or primary systems do, and in the exercise of the imagination that happens to some extent. The broad division is, however, not to be gainsaid.

When we look more closely into the matter, we observe the following. I trace for one minute a cloud passing over the water and note the effect in the change of colour of the sea. If I continued observing for another minute the distance traversed by the cloud would have doubled. Instead, I cease to look for the second minute, and after that find, on reopening my eyes, that the shadow is far removed from where it was when I closed them in truth, the distance is doubled. Allowance must be made for this fact of systematically changing complexes, change, in the scheme of things, being independent of the presence of seen bodies or selves, since these bodies are but small arcs of a large circle. In secondary complications-in association-therefore, the stability and continuous change of the world is tacitly implied. Things, so to speak, change before our eyes, and these changes are registered; when things, then, are found to have been transformed in our absence, the change is assumed to have taken place in precisely the same manner, and a similar conclusion is drawn. Whether I undertake to watch a lengthy process once or twice,

the final result in the first case is accepted as a guarantee that the second observation would have seen a repetition of the first set of changes.

What has been, has been; and hence if the earlier images of the world series continued changing, they would lose their character and become the later, thus destroying the sense of the past, or the series which constitutes the present and the past. The world picture is one, and hence the past is unchangeable. We do not in the strict sense re-develop what happened yesterday, nor is yesterday here; but yesterday is just yesterday, and to live yesterday over again in imagination is yesterday. The past does not insert its tentacles into the present, for then it would not be the past but the present. In the same way an imaged future is a future. It is only when we assume a Subject-a something within a something-that we can mix up past, present and future. The world is one; and past, present and future are what they purport to be.

191.-EVOLUTION.

If we seek for a unitary view of things, it is vain to surreptitiously assume feelings, touches and sights for the purpose of explaining the origin of feelings, touches and sights, i.e., the cutaneous surface and the retina which are to solve the riddle of touch and sight-the world as given— are touches and sights themselves.* In this direction no progress is possible, for the question is begged; while even the end attained in this way gives us merely two relays of sight and touch.

Let us assume a pure visual world, and let us abstract all but visual systems. Then, tracing back its evolution, we expect, as we go back, to find that secondary systems did not assist primary ones, i.e., memories did not assist action; that lines not being membered in relation, dimensional space was not yet developed; and that minuteness of detail and colour were still unevolved. We should gradually work back in this way to something resembling simplified resistance feelings. Accordingly, at the beginning of life, slight changes, favoured by natural selection, would result in slight visual differentiation. As these changes developed, so vision, in this imaginary scheme which only aims at consistency, became pronounced to the extent known at present.

For sight we may substitute any of the other senses, and in that case a sound world or a smell world might develop from the imperfect rudiments referred to above. Still, we must not omit to notice that since the various developed systems-our various sensations-are all complexes, one class of sensation cannot give rise to another, any more than a steel knife can become a steel fork without ceasing to be a steel knife. The successive presence of a sight and a smell, can never argue that the latter evolved

*

As has been pointed out before (sec. 171), if we mean by the skin and the eye the reality which underlies their appearance, then the appearance of trees and houses must be assumed to have underlying them respective realities. There is, therefore, no reason, on this hypothesis, why special importance should be attached to the development of the real or noumenal body, if it is a question of explaining the phenomenal world.

out of the former; for sight, by hypothesis, must first be reduced to resistance feeling or to something which is not sight, before it can change into smell; in other words, sight has first to cease being sight. It is possible, then, to imagine beings whose smell or hearing is so highly developed that they live in a world as complex as their brother visual. The actual stage of human smell attainments, for instance, is immaterial to us here. Already we know that some individuals gain appreciable knowledge and guidance through this sense, while the dog and other animals stand far higher in the scent scale than the human being. Just as a man may, by some keen-scented individual, be distinguished by scent, so may his clothes, and so indeed, might every point on every so-called physical surface. We must, therefore, regard every sense as having the same theoretical and convertible value. Thus by things we might mean certain sound and smell systems, the other systems, on account of their supposed vagueness, being looked upon as appendages to those two.

We have considered separate sense worlds. If we take the world as it is, we have a congeries of senses constituting one world. Instead of tracing forward the development of one sense, we follow the evolution of a number of senses. To imagine a so-called physical world, thought-of as sight and touch, receiving at some point a shock which introduces sight and touch, is a method open to question, though it is one of the current methods of explaining the evolution of mind. Just as sights became differentiated, so did smells and tastes. A seen sense apparatus is a bare visual product, and cannot explain sight, still less the other senses. The body, as a tactile and a visual system, is only a convenient vehicle for following connectedly the constitution of things.

192.-OTHERS.

From the promenade where I often sit I watch the passers-by, and what I specially notice is human bodies which are freely moving. I also hear their voices and see them looking about. Their bodies may be touched and seen, like that one-our own-which can always be touched or seen. If I enter into conversation with one of them, articulate sounds are heard.

Let us examine an instance. The various persons, as seen and touched, are part and parcel of the world around my body, and so far they are uninteresting. They also move freely, their movements conducing sometimes to my welfare, sometimes to the contrary, and so far they are decidedly interesting. If they resemble one another closely as regards sense character, the view received by five of them looking consecutively in one direction from one point is the same, as would be discovered if they exchanged opinions. So with smells and tastes. If five persons simultaneously put their tongues to a sugar loaf, the result in the taste is precisely the same as it was in the sight. If, again, these five experimenters are pricked with a needle scientifically, there will be a pain world, as there was a sight world. So again, under closely related con

ditions, they say and they feel "How fine!" as they look upon an apple tree in blossom. Thus, similarly placed, they re-develop some event in concert, or use the same method to work out a problem. If it be granted that two persons can see the same thing, it must be allowed theoretically that they may equally have all systems in common. To say that "We call physical whatever is the possible object of experience for several subjects, and psychical whatever cannot be experienced by more than one" (Münsterberg, Psychology and Life, 1899, p. 47), is to hold that all the systems may theoretically be at one time physical, at another psychical. To argue that five people looking at one radiantly hot sheet of iron close by them, see something physical, while the pain caused to the eyes of all five by the blinding white iron is psychical, only appears reasonable if we assume that we ought to see the pain if it be one and not five pains (for assuredly the eye-ache-like the sight-" is the possible object of experience for several subjects"). However, this assumption is absurd, since one might as well contend that the seen sheet is psychical because it is not felt as pain. If there be more certainty and uniformity in the one case than in the other, that is accidental, since men might react equally to pains and unequally to sights. It is, therefore, superficial observation only which can speak of one sheet of iron and five pains. Hence we conclude either that there are as many worlds as there are persons or that there is but one world. Münsterberg's distinction does not carry with it conviction.

If we suppose, then, that sensations are alike in all men; it will follow that there are as many worlds as there are persons. In that case there is a separate world in connection with each separate seen body. While, therefore, I should, in the usual way, see a street with 500 people, I have to imagine that each of the 500 sees a street of his own. The world would, under these circumstances, have to be considered as consisting of 500 worlds, as the 500 men certainly sense 500 pictures. Even in this case the unitary conception would still persist, for the one body would simply be placed in imagination, in another place,-just as locomotion gives us ever varying views,-and if the primary systems differed entirely, then it would only be a case of ordinary complexity. By opening and shutting my eyes twice in succession, I obtain two pictures of an object ; I might thus acquire thirty, and can, therefore, readily understand a multiplicity of worlds without affecting fundamentals. Whether, then, there be one like world with many bodies, or many like worlds, no difficulty exists that we need notice.

It is different when one man sees red consistently where another sees green consistently. Here we have a certain seen body and a red view, and another seen body and a green view. If sensations thus consistently differed both as to their elements and their composition, we should truly have a number of worlds. Yet curious as it may seem, the difficulty here

is not as great as it appears. We often see a thing at one time clearly and at another indistinctly, and consequently differences in idiosyncrasy

are readily imagined. We simply say that given a certain body we have a red world, while given another seen body and we have a green world.

In speaking of persistence, it was pointed out that objects or exhausted systems undergo systematic transformations and that every such system has its own history. This is naturally the case with seen human bodies. As but one class among many, these have each their own history. While one piece of pottery falls onto a stone surface and is shattered, another near by remains undisturbed and unbroken. So while one man's palm comes down heavily on a smooth piece of iron, so that the whole hand tingles, another standing by who merely watches him, naturally does not feel the tingling. Different circumstances, different results. Thus throughout the history of living and non-living things the reactions of different individuals diverge rather than run parallel. One of the most striking illustrations of this, is the case of memory. While ten people are seeing or smelling one thing, each of them may be having different secondary visual views, one thinking perhaps of a book and another of a meadow. In this case the visual systems connected with two seen bodies are different. Yet this raises no special difficulty, since the same thing may happen in one seen body: we have merely diverging circumstances and pasts, and hence diverging systems. Where the circumstances converge, there the systems converge also, e.g., two persons think of the same thing in the same words. Accordingly, with complete convergence of circumstances, complete and universal harmony in primary and secondary systems would follow; but this has to do only with the jointedness or the disjointedness of things in general. In closing this section one may remark that with a sense of smell as highly developed as that of sight, we might indifferently speak of the seen body or the smelt body, the visual reference being at present preferred in practice because accidentally it is most marked. [Imagine, in succession, the body having innumerable eyes, ears, noses and palates.]

Bain (Senses and Intellect, 1894, p. 2) argues precisely as Münsterberg does: "In observation, by the senses, we can work in the company of our fellow-beings; the same world that is open to one is open to all, and the impression made is substantially the same for all. In the exercise of introspection, each of us works apart and alone; hence the study of the Subject is purely individual."

193.-SUBJECT AND OBJECT.

The present field of sight reveals an extensive rural view, together with a portion of a seen human body. This view and this body are objects. Studying microscopically a pebble by the roadside, I can see how it is affected by a variety of other objects or exhausted systems far and near. The distant sun warms it, the shadow of the tree above it at a certain time of day cools it, and wind and water round it and disintegrate it. Furthermore, by watching it carefully, I can tell what changes are going on in its environment. From its heat, I argue to the sun's rays; from the passing shadows to the shaking of the foliage above it by the wind. This