VIII[ToC]
THE RELATION OF SENSE-DATA TO PHYSICS
I. THE PROBLEM STATED
Physics is said to be an empirical science, based upon observation and experiment.
It is supposed to be verifiable, i.e. capable of calculating beforehand results subsequently confirmed by observation and experiment.
What can we learn by observation and experiment?
Nothing, so far as physics is concerned, except immediate data of sense: certain patches of colour, sounds, tastes, smells, etc., with certain spatio-temporal relations.
The supposed contents of the physical world are prima facie very different from these: molecules have no colour, atoms make no noise, electrons have no taste, and corpuscles do not even smell.