Matter, for Bergson, is an exaggeration of the tendency in reality, (that is in the actual changing fact directly known) towards logical distinctness, what he calls “spatiality.” His use of the word “matter” in this sense is again, perhaps, like his use of the word “space,” rather misleading. Actual reality, according to him, is never purely material, the only purely material things are abstractions, and these are not real at all but simply fictions. Bergson really means the same thing by “matter” as by “space” and that is simply mutual distinctness of parts and externality of relations, in a word logical complexity. Matter, according to this definition of the word, has no duration and so cannot last through any period of time or change: it simply _is_ in the present, it does not endure but is perpetually destroyed and recreated. The complementary exaggeration which, taken together with matter, completes Berg-son’s explanation of reality, is memory. Just as matter is absolute logical complexity memory is absolute creative synthesis. Together they constitute the hybrid notion of creative duration whose “parts” interpenetrate which, according to Bergson, comes nearest to giving a satisfactory description of the actual fact directly known which is, for him, the whole reality. The best way to accustom one’s mind to these two complementary exaggerations, matter and memory, and to see in more detail the use that Bergson makes of them in explaining the actual facts, will be to examine his theory of sensible perception, since it is just in the act of sensible perception that memory comes in contact with matter. The unsophisticated view is that in sensible perception we become acquainted with things which exist whether we perceive them or not, and these things, taken all together, are commonly called the material world. According to Bergson’s theory also sensible perception is direct acquaintance with matter. The unsophisticated view holds further, however, that this material world with which sensible perception acquaints us is the common sense world of solid tables, green grass, anger and other such states and things and qualities, but we have already seen that this common sense world is really itself only one among the various attempts which science and common sense are continually making to explain the facts in terms of abstractions. The worlds of electrons, vibrations, forces, and so on, constructed by physics, are other attempts to do the same thing and the common sense world of “real” things and qualities has no more claim to actual existence than have any of these scientific hypotheses. Berg-son’s matter is not identified with any one of these constructions, it is that in the facts which they are all attempts to explain in terms of abstractions, the element in the facts upon which abstractions are based and which makes facts classifiable and so explicable.