It was easy then to foresee the necessity of a general theoretical frame in which our duration might take a position which would render it more intelligible by removing its appearance of singular exception. Thus in 1901, I wrote ("Revue de Metaphysique et de Morale", May 1901) with regard to the new philosophy considered as a philosophy of becoming: "It has been prepared by contemporary evolution, which is investigates and perfects, sifting it from its ore of materialism, and turning it into genuine metaphysics. Is not this the philosophy suited to the century of history? Perhaps it indicates that a period has arrived in which mathematics, losing its role as the regulating science, is about to give place to biology." This is the programme carried out, in what an original manner we are well aware, by the doctrine of Creative Evolution. When we examine ancient knowledge, one characteristic of it is at once visible. It studies little but certain privileged moments of changing reality, certain stable forms, certain states of equilibrium. Ancient geometry, for example, is almost always limited to the static consideration of figures already traced. Modern science is quite different. Has not the greatest progress which it has realised in the mathematical order really been the invention of infinitesimal analysis; that is to say, an effort to substitute the process for the resultant, to follow the moving generation of phenomena and magnitudes in its continuity, to place oneself along becoming at any moment whatsoever, or rather, by degrees at all successive moments? This fundamental tendency, coupled with the development of biological research, was bound to incline it towards a doctrine of evolution; and hence the success of Spencer. But time, which is everywhere in modern science the chief variable, is only a time-length, indefinitely and arbitrarily divisible. There is no genuine duration, nothing really tending to evolution in Spencer's evolution: no more than there is in the periodic working of a turbine or in the stationary tremble of a diapason. Is not this what is emphasised by the perpetual employment of mechanical images and vulgar engineering metaphors, the least fault of which is to suppose a homogeneous time, and a motionless theatre of change which is at bottom only space? "In such a doctrine we still talk of time, we pronounce the word, but we hardly think of the thing; for time is here robbed of all effect." ("Creative Evolution", page 42.) Whence comes a latent materialism, ready to grasp the chance of self-expression. Whence the automatic return to the dream of universal arithmetic, which Laplace, Du Bois-Reymond, and Huxley have expressed with such precision. (Ibid., page 41.)