History of Western Philosophy - Bertrand Russell [456]
Apart from the question of number, which we have already considered, the chief point at which Bergson touches mathematics is his rejection of what he calls the 'cinematographic' representation of the world. Mathematics conceives change, even continuous change, as constituted by a series of states; Bergson, on the contrary, contends that no series of states can represent what is continuous, and that in change a thing is never in any state at all. The view that change is constituted by a series of changing states he calls cinematographic; this view, he says, is natural to the intellect, but is radically vicious. True change can only be explained by true duration; it involves an interpenetration of past and present, not a mathematical succession of static states. This is what is called a 'dynamic' instead of a 'static' view of the world. The question is important, and in spite of its difficulty we cannot pass it by.
Bergson's theory of duration is bound up with his theory of memory. According to this theory, things remembered survive in memory, and thus interpenetrate present things: past and present are not mutually external, but are mingled in the unity of consciousness. Action, he says, is what constitutes being; but mathematical time is a mere passive receptacle, which does nothing and therefore is nothing. The past, he says, is that which acts no longer, and the present is that which is acting. But in this statement, as indeed throughout his account of duration, Bergson is unconsciously assuming the ordinary mathematical time; without this, his statements are unmeaning. What is meant by saying 'the past is essentially that which acts no longer' (his italics), except that the past is that of which the action is past? the words 'no longer' are words expressive of the past; to a person who did not have the ordinary notion of the past as something outside the present, these words would have no meaning. Thus his definition is circular. What he says is, in effect, 'the past is that of which the action is in the past'. As a definition, this cannot be regarded as a happy effort. And the same applies to the present. The present, we are told, is 'that which is acting' (his italics). But the word 'is' introduces just that idea of the present which was to be defined. The present is that which is acting as opposed to that which was acting or will be acting. That is to say, the present is that whose action is in the present, not in the past or in the future. Again the definition is circular. An earlier passage on the same page will illustrate the fallacy further. 'That which constitutes our pure perception,' he says, 'is our dawning action…. The actuality of our perception thus lies in its activity, in the movements which prolong it, and not in its greater intensity: the past is only idea, the present is ideo-motor.' This passage makes it quite clear that, when Bergson speaks of the past, he does not mean the past, but our present memory of the past. The past when it existed was just as active as the present is now; if Bergson's account were correct, the present moment ought to be the only one in the whole history of the world containing any activity. In earlier times there were other perceptions, just as active, just as actual in their day, as our present perceptions; the past, in its day, was by no means only idea, but was in its intrinsic character just what the present is now. This real past, however, Bergson simply forgets; what he speaks of is the present idea of the past. The real past does not mingle with the present, since it is not part of it; but that is a very different thing.
The whole of Bergson's theory of duration and time rests