I'm not afraid to fall in love. I'm afraid of the person I'll become when I'm in love.
Man will not merely endure: he will prevail.
The more we learn about the universe, the more we realize how much we have yet to discover.
The greatest problem for mathematicians now is probably the Riemann Hypothesis.
My mind is my weapon. My brother has his sword, King Robert has his warhammer, and I have my mind... And a mind needs books as a sword needs a whetstone, if it is to keep its edge.