Dissent is the mark of freedom, as originality is the mark of independence of mind. … No one can be a scientist … if he does not have independence of observation and of thought.
To imagine is the characteristic act, not of the poet's mind, or the painter's, or the scientist's, but of the mind of man.
Astronomy is not the apex of science or of invention. But it is a test of the cast of temperament and mind that underlies a culture.
The wish to hurt, the momentary intoxication with pain, is the loophole through which the pervert climbs into the minds of ordinary men.