in each an enormous multiplicity of vibrations which appear to us all at once, although they are successive. If we were only to divide, ideally, this undivided depth of time, to distinguish in it the necessary multiplicity of moments, in a word to eliminate all memory, we should pass thereby from perception to matter, from the subject to the object. Then matter, becoming more and more homogeneous as our extended sensations spread themselves over a greater number of moments, would tend more and more towards that system of homogeneous vibrations of which realism tells us, although it would never coincide entirely with them. There would be no need to assume, on the one hand, space with unperceived movements, and, on the other, consciousness with unextended sensations. Subject and object would unite in an extended perception the subjective side of perception being the contraction effected by memory, and the objective reality of matter fusing with the multitudinous and successive vibrations into which this perception can be internally broken up. Such at least is the conclusion which, we hope, will issue clearly from the last part of this essay. Questions relating to subject and object, to their distinction and their union, should be put in terms of time rather than of space.
But our distinction between 'pure perception' and 'pure memory' has yet another aim. Just as pure perception, by giving us hints as to the
