back to the earlier date at a bound, all the intermediate past escapes its hold. The same reasons, then, which bring about that our perceptions range themselves in strict continuity in space, cause our memories to be illumined discontinuously in time. We have not, in regard to objects unperceived in space and unconscious memories in time, to do with two radically different forms of existence; but the exigencies of action are the inverse in the one case of what they are in the other.
But here we come to the capital problem of existence, a problem we can only glance at, forExistence implies both conscious apprehension and regular connexion; but there may be different degrees of either. otherwise it would lead us step by step into the heart of metaphysics. We will merely say that with regard to matters of experience—which alone concern us here—existence appears to imply two conditions taken together: (1) presentation in consciousness; and (2) the logical or causal connexion of that which is so presented with what precedes and with what follows. The reality for us of a psychical state or of a material object consists in the double fact that our consciousness perceives them and that they form part of a series, temporal or spatial, of which the elements determine each other. But these two conditions admit of degrees, and it is conceivable that, though both are necessary, they may be unequally fulfilled. Thus, in the case of actual internal states, the connexion is less close, and the determination of the present by the past, leav-
