We sail within a vast sphere, ever drifting in uncertainty, driven from end to end.

Il n'est pas certain que tout soit incertain.
(Translation: It is not certain that everything is uncertain.)

Nature is an infinite sphere of which the center is everywhere and the circumference nowhere.

However vast a man's spiritual resources, he is capable of but one great passion

Happiness is neither without us nor within us. It is in God, both without us and within us.

If we must not act save on a certainty, we ought not to act on religion, for it is not certain. But how many things we do on an uncertainty, sea voyages, battles!