The man with a new idea is a Crank until the idea succeeds.

There are four powers: memory and intellect, desire and covetousness. The two first are mental and the others sensual. The three senses sight, hearing, and smell cannot well be prevented; touch and taste not at all.

I have far more respect for the person with a single idea who gets there than for the person with a thousand ideas who does nothing.

If at first the idea is not absurd, then there is no hope for it.

No idea is so outlandish that it should not be considered with a searching but at the same time a steady eye.

Experience is the only teacher we have.