kicked them, just as a bell rings when you shake it, without any feeling whatever.

Thus the Principle of Simplicity or Parsimony is one that we are compelled to follow, but often it is hard to tell whether we will not reach it sooner in the end by leaving it for the moment.

The right to assume these

principles.

Of course it is one thing to be so organized that the simple and familiar are more easily believed in than the complicated and unfamiliar, and a somewhat different thing to accept the formal principle that where there are two theories, equally good in other respects, that which assumes the simpler and more familiar state of affairs is the more likely to be true. And yet if we have the organization, we can hardly avoid the principle. To say that the simpler and more familiar is more easily believed in means that in most cases we do believe in it, or, in other words, that in most cases the relatively simple and familiar state of affairs is what we call the 'true' one; and now, a large number of particular cases being settled, all we have to do is to compare them and we reach our formal principle: The theory which supposes the simpler and more familiar state of affairs is more often true than the other.*

It is because we act on this principle of discrediting the new, whether we ever state it in words or not, that the phrase 'a very strange story' generally means a lie.

So much for the fact that we actually do use Consistency, Conceivability, and Uniformity and Simplicity as tests of truth, and even for the further fact that we come to think we have a right to. But have we this right? Is it possible to prove that there is such a relation in the world as com

*We get the principle when we reflect enough to see the results of our own organization (i.e., to see that all our explanations are relatively simple) but not enough to see that they are the results of that organization (i.e., that these explanations are simple because the simple ones are those we chose). When we see that the question takes a new form.

patibility or incompatibility? Can we prove that anything real conforms or ought to conform to the laws of our imagination? Hardest of all, can we prove that because something is uniform or simple and therefore easy for us to think of, it is any easier on that account for it to exist? And if we cannot prove these things, have we any real right to use the tests? My answer so far as uniformity is concerned has been given already in Chapter XXII. I believe that we cannot prove these things, and therefore cannot prove our right to use the tests. We simply take them for granted and take the right to use the tests for granted along with them.

The time has gone by long since when wise men sought for a philosophy without assumptions; and if we cannot get along without them in philosophy, we certainly cannot get along without them in common life and in the logic that tries to serve as a guide for common life. If any one believes, as Kant did, that not only colors and sounds and smells and tastes, but also Space and Time with all their relations of shape, size, distance, direction, duration, coexistence, and succession, are purely human ways of imagining things and do not really belong to things in themselves at all, then that person ought not to use conceivability as a test of what things. in themselves can or cannot be. If any one has meditated about these topics so long that it no longer seems to him absurd to doubt the simplicity and general rationality of Nature, I do not see how it is possible to restore his faith by demonstration; and if he has emancipated himself from the bonds of habit so completely that he really doubts the existence of those principles of uniformity that we indicate by the words Thing and Kind and Cause and Law, then there is certainly no way of proving to him that one explanation is better than another, or indeed that anything needs explanation at all. If, finally, he really and truly doubts—as Descartes tried to the existence of everything but his own passing thought, I do not see how we could prove to his satisfaction that there is a real nature of things in virtue of

which one supposed fact is incompatible with another, and therefore that there really is such a thing as a contradiction.

If people actually doubt all these things, we do not argue with them we lock them up instead, and by this resort to brute force we confess defeat in the field of pure argument. If, on the other hand, they profess to doubt them, but show by their acts or their argument—perhaps by the very fact of talking with us that when they are off their guard they really take them for granted, the most we can do is to point out the inconsistency, with the hope that their faith in law and a nature of things is so strong at bottom that inconsistency in an argument will seem to them a fault. We cannot go beyond this appeal to faith. Thus we start with faith in experience as a whole, however vaguely we may conceive of this experience; but such a faith implies also faith in all the ultimate principles that that experience involves.

There are some questions which logic and its tests of truth will never help us to settle. If it is a question whether a certain state of affairs exists, and if there is no

objection so far as consistency and conceivability The limits are concerned to believing that it does, the only

way of settling the question is to ask whether any one has observed the state of affairs itself or anything that can be recognized as its necessary cause or effect. If we cannɔt observe the state of affairs itself and if we cannot prove that anything which we do observe must be connected causally with something of the sort, we cannot prove that it exists. But if the state of affairs in question is one that might exist without being observed or producing unmistakable effects, we cannot prove either that it does not exist. It may be that

there are mountains on the other side of the moon; but we cannot see them, and we do not know of any change that they would make in what we do see if they were there; consequently we cannot tell whether they are there or not. It may be that plants feel, that they enjoy the sunlight and the rain and suffer discomfort in the cold; but feelings can

never be perceived directly except in ourselves, and we have no idea what change their presence or their absence would make in the behavior of a plant, and so we can never know whether plants have them or not. It may be that every living soul existed on the earth before in the body of some man or beast although it has forgotten what took place in its life there; but no one knows how the life of a reincarnated soul should differ from that of one that never lived before, and so no one can ever tell from what he observes whether the theory of transmigration is true or not. It may be, finally, that the world was created in infinite love and wisdom and that all our human experiences are intended as preparations for some glorified life after death; but no one knows enough about infinite love and wisdom to say how a world made by it would differ from any other world, or how a life intended by the Creator as a preparation for another would differ from one which was not; and therefore nothing that we observe in the world can prove the matter one way or the other.

What we believe about questions like these is not inferred by logical processes from what we observe in the world; but is added to what we observe, as a matter of religious faith. Such a faith gives our experiences a new kind of significance; but no particular experience of the sort that science deals with can either confirm or refute that faith; and this is why different people often give diametrically opposite religious interpretations to the same concrete experiences.

It often seems indeed to persons of a certain temperament or character that some observable fact is a sufficient proof of what they believe about religion; and perhaps they make long abstract arguments to show it; but abstract arguments are hard to criticise in any case, and it requires an unusual amount of intellectual honesty and energy to seek for obscure fallacies in arguments that profess to prove what we already believe or wish to believe; and so this appearance of logical proof is easy enough to account for.

There is only one way in which logic or a knowledge of

It can

scientific method can help us in matters of this kind. show us its own limitations, and save us in this way, on the one hand, from the trouble of constructing long and labored arguments that do not prove anything, and, on the other, from the error of supposing that the absence of proof in favor of certain beliefs can be taken as any argument against them.

Science and faith, particularly religious faith, are often supposed to be in some kind of logical conflict with each other. But this is a mistake. Science itself rests on faith, for it assumes, as we have seen, that there is such a thing as a world beyond one's own individual sensations, and that that world really possesses the uniformity and coherence which we feel impelled, as creatures of habit, to read into it. Indeed what we call scientific knowledge' is simply an interpretation that we give to our experience or some of it on the basis of this faith. But a faith in uniformity and coherence is certainly not inconsistent with a faith in purpose and wisdom and goodness also, and the mere fact that science does not attempt to unify experience from the standpoint of this latter faith as well as from that of the former is no reason why the scientist should not do so when he leaves his science and begins to think of something else. Religion cannot tell what the world looks like, and science cannot tell anything about its spiritual values; but for this very reason the one is no more inconsistent with the other than geometry or psychology is inconsistent with æsthetics or jurisprudence.