Science can only ascertain what is, but not what should be, and outside of its domain value judgements of all kinds remain necessary.

Stand still. The trees ahead and bush beside you are not lost.

As for the search for truth, I know from my own painful searching, with its many blind alleys, how hard it is to take a reliable step, be it ever so small, towards the understanding of that which is truly significant.

Freedom of teaching and of opinion in book or press is the foundation for the sound and natural development of any people.

Lasting harmony with a woman (was) an undertaking in which I twice failed rather disgracefully.

A happy man is too satisfied with the present to dwell too much on the future.

To have a better life we must keep choosing how we are living.