Claude Bernard

It is what we know already that often prevents us from learning.

The true worth of an experimenter consists in his pursuing not only what he seeks in his experiment, but also what he did not seek.

Man can learn nothing except by going from the known to the unknown.

I laugh at absurdity hardest, then stories, then observations, then bearded men on roller skates.

In the early days of aviation, there was a great deal of experimentation and a high death rate.

Perseverance is a positive, active characteristic.