But it is principally before logical and philosophical criticism, that Mechanism seems to give way completely. Those very ideas on the nature of explanation, according to which it is attempted to reduce all reality to terms of the supposed primary notions of mass and motion, preclude Mechanism from ever attaining the
whole of reality. The present must be reduced to the past, the new to that which is already known, the complex to the more simple; but this original datum remains, that the complex and the simple are not identical, that the new fact is not the fact which was already known. If we suppose all that was contained in the complex to have been reduced by analysis to simple elements already known, we have still to explain their combination, their unity in the complex; and it is just these that have been destroyed by the explanatory analysis. Given that there is something to explain, something unknown, it is clear that there is something beyond the known and the old, and there must inevitably be some principle which moulds into unity the numerous elements, and which either for the species or for the individual, may in a very broad sense be called the "form". Explanations based on analysis do not discover the form, because they begin by destroying it. It may be said, in a particular but entirely acceptable sense, that "form" explains nothing, because to explain is to reduce, and form is by its very nature irreducible. But from this to the denial of form is a very far cry. The scholastics of the decadent period erred in regarding forms as explanatory principles, but Mechanism distorts the reality by reducing it to its "matter", by ignoring its specific and its individual unity. For the same reason, the mechanical interpretations of the dynamic aspect of things, that is to say of cosmic evolution, prove futile. It is of course instructive in the highest degree to know what previous state of the universe accounts for the present state of things; but to look on those anterior efficient causes of things as the adequate representations of their effects, is to lose sight of the fact that these latter are
effects, while the former were
causes; the consequence is an absolute "statism" and a denial of all causality.
Similar observations might be made on the subject of final causes. The meaning itself of the word finality has undergone singular changes since Aristotle and the thirteenth century. Let it suffice to note that finality has its basis in the intellectual nature of an efficient cause, or in the internal tendency of a form viewed from the standpoint of activity, of dynamism. The decadent Scholastics weakened their position when they relied on forms and ends only as means of scientific explanations strictly so called, while Mechanists are clearly in error when they seek in these same scientific explanations for an account of reality to the exclusion of forms and ends. More might be said of the manifest inadequacy of quantitative images, of cosmological Mathematism which reduces all continuity to discontinuity and all time to coincidences without duration, and of the anti-mechanistic reaction which asserts itself under the name of Energism, and with which the researches of Ostwald and of Duhem are associated. But these are complex and general problems. We may now resume and draw our conclusions.
t, the change in velocity is given by Equatio. So, to get the same