To sum up: The existence of experience is a fact, and as such, cannot significantly be doubted. But experience consists essentially in the presentation of an object to a subject, and has no meaning which does not involve the existence of both the latter. The existence of the subject being once granted, propositions can be asserted concerning it. These constitute pieces of knowledge of a kind which has been termed 'knowledge by description.' Such knowledge is fundamentally distinct from that concrete realization of our own existence, which can in no sense be termed knowledge in itself, but which is, for us, the central and most abiding fact of all.
The existence of at least one self being granted, we proceed to assume the existence of other selves. This assumption is in accordance with the pluralistic hypothesis and is justifiable, for it in no way conflicts with the facts. It cannot be proved by the latter, however, so that it is an assumption; but it must be remembered that no philosophy can proceed without it. Solipsism is logically irrefutable, but quite barren. A man who is not a solipsist can prove a solipsist to be wrong to his own satisfaction, for he knows that he exists; but he cannot prove to the solipsist himself that he is wrong. To all such attempts, the latter simply replies that the whole thing is merely part of a particularly vivid dream of his own. On the other hand, solipsism is equally unable to prove its case, so that we are at liberty to assume the existence of other people. This assumption is a most valuable one, for it at once opens to us an immense fresh store of knowledge by description, in addition to the knowledge we have through our own immediate sense-experience.
VI. Continuity.—Turning to the objective side of experience, we find in what is called the 'continuity' of experience, a source of difficulty which has been keenly realized by philosophers of all periods. The new realists claim to have disposed of the difficulties by means of their new scientific method, but the sort of continuity they are led to, is not the sort of continuity we find in experience, although, for most purposes, it may represent it adequately enough.
