Nothing should be valued higher than the value of the day.

The most difficult thing is what is thought to be the simplest; to really see the things which are before your eyes.

Everything in science depends on what one calls an aperçu, on becoming aware of what is at the bottom of the phenomena. Such becoming aware is infinitely fertile.

But the valid issue is the extent to which man knows how to form and master the material at his command.

We are our own aptest deceiver.

Few men have imagination enough for reality.

The miller imagines that the corn grows only to make his mill turn.