Science has made us gods even before we are worthy of being men.

We must watch over our modesty in the presence of those who cannot understand its grounds.

When I was young I pitied the old. Now old, it is the young I pity.

On the brink of being satiated, desire still appears infinite.

One must credit an hypothesis with all that has had to be discovered in order to demolish it.

The books one has written in the past have two surprises in store: one couldn't write them again, and wouldn't want to.

The nobility of a human being is strictly independent of that of his convictions.