We are thus brought back to the distinction which we set up above between the multiplicity of juxtaposition and that of fusion or interpenetration. Such and such a feeling such and such an idea, contains an indefinite plurality of conscious states: but the plurality will not be observed unless it is, as it were, spread out in this homogeneous medium which some call duration, but which is in reality space. We shall then perceive terms external to one another, and these terms will no longer be the states of consciousness themselves, but their symbols, or, speaking more exactly, the words which express them. There is, as we have pointed out, a close connexion between the faculty of conceiving a homogeneous medium, such as space, and that of thinking by means of general ideas. As soon as we try to give an account of a conscious state, to analyse it, this state, which is above all personal, will be resolved into impersonal elements external to one another, each of which calls up the idea of a genus and is expressed by a word. But because our reason, equipped with the idea of space and the power of creating symbols, draws these multiple elements out of the whole, it does not follow that they were contained in it. For within the whole they did not occupy space and did not care to express themselves by means of symbols; they permeated and melted into one another. Associationism thus makes the mistake of constantly replacing the concrete phenomenon which takes place in the mind by the artificial reconstruction of it given by philosophy, and of thus confusing the explanation of the fact with the fact itself. We shall perceive this more clearly as we consider deeper and more comprehensive psychic states. [Sidenote: Failure of associationism to explain the deeper states of the self.]