Love is not the stupidest thing a man does, but it cannot be blamed on gravity.

Teaching should be such that what is offered is perceived as a valuable gift and not as hard duty. Never regard study as duty but as the enviable opportunity to learn to know the liberating influence of beauty in the realm of the spirit for your own personal joy and to the profit of the community to which your later work belongs.

Everyone should be respected as an individual, but no one idolized.

Older men start wars, but younger men fight them.

Money only appeals to selfishness and always tempts its owners irresistibly to abuse it. Can anyone imagine Moses, Jesus, or Gandhi armed with the money-bags of Carnegie?

I don't believe in mathematics.

It is open to every man to choose the direction of his striving; and also every man may draw comfort from Lessing's fine saying, that the search for truth is more precious than its possession.