Mathematics is not yet ready for such problems.
In reference to Collatz's problem, attributed by Paul Halmos.
Why are numbers beautiful? It's like asking why is Beethoven's Ninth Symphony beautiful. If you don't see why, someone can't tell you. I know numbers are beautiful. If they aren't beautiful, nothing is.
Television is something the Russians invented to destroy American education.
Why are you a physicist? Why aren't you a mathematician?
I cannot compute Cm for m > 3. This may be due to old age, stupidity, and laziness.
The purpose of life is to prove and to conjecture.
There'll be plenty of time to rest in the grave.
My mother said, "Even you, Paul, can be in only one place at one time." Maybe soon I will be relieved of this disadvantage. Maybe, once I've left, I'll be able to be in many places at the same time. Maybe then I'll be able to collaborate with Archimedes and Euclid.
There are three signs of senility. The first sign is that a man forgets his theorems. The second sign is that he forgets to zip up. The third sign is that he forgets to zip down.
Every human activity, good or bad, except mathematics, must come to an end.
Here I am. My brain is open.