The further one advances in experience, the closer one comes to the unfathomable; the more one learns to utilize experience, the more one recognizes that the unfathomable is of no practical value.

The deepest, the only theme of human history, compared to which all others are of subordinate importance, is the conflict of skepticism with faith.

Knowing is not enough; we must apply. Willing is not enough; we must do.

The world only goes forward because of those who oppose it.

The artist alone sees spirits. But after he has told of their appearing to him, everybody sees them.

Life is not anything, but an opportunity for something.

Daily life is more instructive than the most effective book.