Now experience...

Now experience, as unfolding itself in time, presents three main levels - the level of matter, the level of life, and the level of mind and consciousness - the subject-matter of physics, biology, and psychology, respectively. Let us first turn our attention to matter. In order exactly to appreciate the position of modern physics it is necessary to understand clearly what we mean by matter. Physics, as an empirical science, deals with the facts of experience, i.e. sense-experience.

The physicist begins and ends with sensible phenomena, without which it is impossible for him to verify his theories. He may postulate imperceptible entities,…