Bergson would not think of denying that this intellectual method, in
which facts are used as material for abstraction, is of the utmost
practical use for explaining facts and so enabling us to control them.
He suggests, however, that our preoccupation with these useful
abstractions, classes and their relations, misleads us as to the facts
themselves. What actually takes place, he thinks, is a kind of
substitution of the explanation for the fact which was to be
explained, analogous with what happens when a child at a party, or a
guest at dinner, is misled about his actual sensations, only this
substitution of which Bergson speaks, being habitual, is much harder
to see through. Explanation, as we have seen, consists in constructing
a plan or map in terms of such abstractions as classes and their
relations, or sometimes, when the abstraction has been carried a step
further, in terms simply of words or symbols, by means of which we
represent the causal relations between such of the actual directly
known facts as can be classified. This plan is more comprehensive and
complete than the actual facts which we know directly in the ordinary
course of things, for which it stands, and it enables us to explain
these facts in terms of the classes of causes from which they follow,
and the classes of effects which they produce. No explanation, of
course, can actually acquaint us directly with the real antecedent or
consequent facts themselves: it can only tell us to what classes these
facts must belong. The terms of the plan by which we explain the
facts, the classes, for instance, daylight and darkness, and their
relation of alternation, or the words or symbols which stand for
classes and relations are not themselves facts but abstractions. We
cannot think in terms of actual facts: the intellectual activity by
which we formulate general laws can only work among abstractions, and
in order to explain a fact we are obliged to substitute for it either