3 is prime, 5 is prime, 7 is prime, 9 is a paradox; as is a paradox why the number 1 is not prime if it has no other divisors besides himself.

One of the chief triumphs of modern mathematics consists in having discovered what mathematics really is.

The first step in a fascist movement is the combination under an energetic leader of a number of men who possess more than the average share of leisure, brutality, and stupidity. The next step is to fascinate fools and muzzle the intelligent, by emotional excitement on the one hand and terrorism on the other.

What men really want is not knowledge but certainty.

Neither acquiescence in skepticism nor acquiescence in dogma is what education should produce.

Reason may be a small force, but it is constant, and works always in one direction, while the forces of unreason destroy one another in futile strife.

It is undesirable to believe a proposition when there is no ground whatever for supposing it true