The critique of science, which is so prominent in Boutroux, was characteristic of a number of thinkers whom we cannot do more than mention here in passing, for in general their work is not in line with the spiritualist development, but is a sub-current running out and separated from the main stream. This is shown prominently in the fact that, while Boutroux’s critique is in the interests of idealism and the maintenance of some spiritual values, much subsequent criticism of science is a mere empiricism and, being divorced from the general principles of the spiritualist philosophy, tends merely to accentuate a vein of uncertainty—indeed, scepticism of knowledge. Such is the general standpoint taken by Milhaud, Payot, and Duhem. Rather apart from these stands the works of acute minds like Poincaré, Durand de Gros, and Hannequin, whose discussion of the atomic doctrines is a work of considerable merit. To these may be added Lalande’s criticism of the doctrine of evolution and integration by his opposing to it that of dissolution and disintegration. Passing references to these books must not, however, detain us from following the main development which, from Boutroux, is carried on by Bergson. We find that Bergson, like Boutroux, holds no brief for science, and in particular he opposes some of its doctrines which have been dogmatically and uncritically accepted. His work, _Matiére et Mémoire_, is a direct critique of the scientific postulate of psycho-physical parallelism which Bergson regards as the crux of the problem at issue between science and philosophy—namely, that of freedom. He shows that this theory, which has been adopted by science because of its convenience, ought not to be accepted by philosophy without criticism. In his opinion it cannot stand the criticism which he brings against it. A relation between soul and body is undeniable, but he does not agree that that relation is one of absolute parallelism. To maintain parallelism is to settle at once and beforehand, in an unwarrantably _a priori_ manner, the whole problem of freedom. His intense spiritualism sees also in such a doctrine the deadly enemy Epiphenomenalism, the belief that the spiritual is only a product of the physical. He maintains the unique and irreducible nature of consciousness, and claims that the life of the soul or spirit is richer and wider than the mere physical activity of the brain, which is really its instrument. Bergson asks us to imagine the revolution which might have been, had our early scientists devoted themselves to the study of mind rather than matter, and claims that we suffer from the dogmatism of materialistic science and the geometrical and mathematical conceptions of “a universal science” or “mathematic” which come from the seventeenth century, and are seen later in Taine.