As I have not the slightest intention of giving even an abridged history of materialism, let us come at once to the present day, and endeavour to say in what consists the scientific form this doctrine has assumed. Its fundamental basis has not changed. It still rests on our tendency to give chief importance to what can be seen and touched; and it is an effect of the hegemony of three of our senses, the visual, the tactile, and the muscular.
The extraordinary development of the physical sciences has no doubt given an enormous encouragement to materialism, and it may be said that in the philosophy of nature it occupies a principal place, and that it is there in its own domain and unassailable.
It has become the expression of the idea that everything that can be explained scientifically, everything susceptible of being measured, is a material phenomenon. It is the representation of the material explanation pushed to its last limits, and all experiments, all calculations, all inductions resting on the grand principle of the conservation of matter and energy plead in its favour.
We will examine with some precision how far such a doctrine solves the problem of the existence of the intellectual functions.
The doctrine has understood this connection as