Reality is the cage of those who lack imagination.

I have tried to show why I believe that the biologist is the most romantic figure on earth at the present day. At first sight he seems to be just a poor little scrubby underpaid man, groping blindly amid the mazes of the ultra-microscopic, engaging in bitter and lifelong quarrels over the nephridia of flatworms, waking perhaps one morning to find that someone whose name he has never heard has demolished by a few crucial experiments the work which he had hoped would render him immortal.

The idea of protoplasm, which was really a name for our ignorance, [is] only a little less misleading than the expression "Vital force".

I will give up my belief in evolution if someone finds a fossil rabbit in the Precambrian.

The extreme socialists desire to run every nation as a single business concern.

In fact, words are well adapted for description and the arousing of emotion, but for many kinds of precise thought other symbols are much better.

There can be no truce between science and religion.