Distinctly different as a child, as an adolescent, in his prime and in his old age, man considers himself as one, not because he acts, but because he knows.

People of talent resemble a musical instrument more closely than they do a musician. Without outside help, they produce not a single sound, but given even the slightest touch, and a magnificent tune emanates from them.

Metaphysics must be based on what exists, for it has the task of explicating it.

Whoever places his trust into a system will soon be without a home. While you are building your third story, the two lower ones have already been dismantled.

A book is quite a beautiful thing, even more so learning. Together, however, all they amount to is called book-learning.

Genius differs from talent not by the amount of original thoughts, but by making the latter fertile and by positioning them properly, in other words, by integrating everything into a whole, whereas talent produces only fragments, no matter how beautiful.

Let no one say that taking action is hard. Action is aided by courage, by the moment, by impulse, and the hardest thing in the world is making a decision.