The fact is, every thinker, every philosopher, the moment he is forced to abandon his one-sided intellectual occupation by practical necessity, immediately returns to the general point of view of mankind.

Science always has its origin in the adaptation of thought to some definite field of experience.

Man is pre-eminently endowed with the power of voluntarily and consciously determining his own point of view.

Physics is experience, arranged in economical order.

Ordinarily pleasure and pain are regarded as different from sensations.

The biological task of science is to provide the fully developed human individual with as perfect a means of orientating himself as possible. No other scientific ideal can be realised, and any other must be meaningless.

I once knew an otherwise excellent teacher who compelled his students to perform all their demonstrations with incorrect figures, on the theory that it was the logical connection of the concepts, not the figure, that was essential.