The fly that doesn't want to be swatted is most secure when it lights on the fly-swatter.

When a book and a head collide and a hollow sound is heard, must it always have come from the book?

There can hardly be a stranger commodity in the world than books. Printed by people who don't understand them; sold by people who don't understand them; bound, criticized and read by people who don't understand them; and now even written by people who don't understand them.

Rational free spirits are the light brigade who go on ahead and reconnoiter the ground which the heavy brigade of the orthodox will eventually occupy.

Much reading has brought upon us a learned barbarism.

So-called professional mathematicians have, in their reliance on the relative incapacity of the rest of mankind, acquired for themselves a reputation for profundity very similar to the reputation for sanctity possessed by theologians.

Never undertake anything for which you wouldn't have the courage to ask the blessings of heaven.