There are certain moments when we might wish the future were built by men of the past.

A body of work such as Pasteur's is inconceivable in our time: no man would be given a chance to create a whole science. Nowadays a path is scarcely opened up when the crowd begins to pour in.

It is not easy to imagine how little interested a scientist usually is in the work of any other, with the possible exception of the teacher who backs him or the student who honors him.

What makes our opponents useful is that they allow us to believe that without them we would be able to realize our goals.

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

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

Stupidity, outrage, vanity, cruelty, iniquity, bad faith, falsehood - we fail to see the whole array when it is facing in the same direction as we.