Page:Philosophical Review Volume 27.djvu/248

236 We usually look upon hypotheses as put forward to 'explain' certain groups of facts. Let the case of physical science serve as an illustration. As a rule, men of science are content to dismiss the data of sense as merely 'subjective.' They look upon them as due to the action of certain hypothetical entities on our senses. The function of such an hypothesis, however, is not really explanatory, but simply an attempt to describe the facts of existence in the simplest possible terms. The immediate facts of existence are confused, complex, and loosely ordered. Any attempt to deal with them as they stand, for the purpose of calculated interference in the course of events, will be foredoomed to hopeless failure. Consequently, physics introduces such conceptions as those of a material particle and a luminiferous ether, in order to unify and coördinate the phenomena, so as to render them amenable to mathematical treatment.

The majority of hypotheses are merely descriptive in this way. They are attempts to describe the facts of existence in simpler terms than the immediately given data. It might therefore be urged that pluralism is also a merely descriptive hypothesis, the 'explanation' being simply taken back one step, and expressed in terms of different things. Yet it is just in this difference of terms that the root of the essential disparity between pluralism and other hypotheses is to be found. It implies a difference of type. For pluralism is expressed in terms of active selves. We all realize what it is to be active—it is just living and doing. We all realize what a self is. This realization is far more than knowledge in the ordinary sense. It is something of what the older thinkers were trying to express when they said that for perfect knowledge, knower and known must be one. It is a unique, supremely intimate fact, and therefore stands in a class of its own. It cannot be subsumed under one of the three types of knowledge proper—knowledge by acquaintance, knowledge by description, and knowledge of logical truths. It is this last fact which so often causes the realization of the nature and existence of self to be passed by, with the inevitable consequence that doubt is expressed of the existence of self at all.