"A professor can never better distinguish himself in his work than by encouraging a clever pupil, for the true discoverers are among them, as comets amongst the stars."

"The greatest pleasure in life is to be able to do what you love."

"Nature's economy shall be the base for our own, for it is immutable, but ours is secondary. An economist without knowledge of nature is therefore like a physicist without knowledge of mathematics."

"I demand of you, and of the whole world, that you show me a generic character... by which to distinguish between Man and Ape. I myself most assuredly know of none. But perhaps I should still do it acc…"

"Homo sapiens, nosce te ipsum. (Man, know thyself.)"