It is necessary to believe that the mixture of evil has produced the greatest possible good: otherwise the evil would not have been permitted.

It's easier to be original and foolish than original and wise.

There is a certain destiny of everything, regulated by the foreknowledge and providence of God in His works.

I hold that it is only when we can prove everything we assert that we understand perfectly the thing under consideration.

Nothing is more important than to see the sources of invention which are, in my opinion more interesting than the inventions themselves.

I am so in favor of the actual infinite that instead of admitting that Nature abhors it, as is commonly said, I hold that Nature makes frequent use of it everywhere, in order to show more effectively the perfections of its Author.

The greatness of a life can only be estimated by the multitude of its actions. We should not count the years, it is our actions which constitute our life.