Page:Leibniz Discourse on Metaphysics etc (1908).djvu/11

x in terms of motion. In this way all the problems tend to become problems of mechanics; change of position, change of form, change of motion—these are the principles to which our physicists and our chemists have recourse whenever they can.

It is therefore wrong to say that the Cartesian line of thought has completely failed and that modern science has been moving away from it more and more. On the contrary we are witnessing the daily extension of mechanicalism in the science of our time. The question takes on a different phase when it is asked whether mechanicalism is the final word of nature, whether it is self-sufficient, in fact whether the principles of mechanicalism are themselves mechanical. This is a wholly metaphysical question and does not at all affect positive science; for the phenomena will be explained in the same way whether matter is thought of as inert, composed of little particles which are moved and combined by invisible hands, or whether an interior activity and a sort of spontaneity is attributed to them. For the physicist and for the chemist, forces are only words representing unknown causes. For the metaphysician they are real activities. It is metaphysics, therefore, and not physics which is rising above mechanicalism. It is in metaphysics that mechanicalism has found, not its contradiction, but its completion through the doctrine of dynamism. It is this latter direction that philosophy has mainly taken since Descartes and in this the prime mover was Leibniz.