Life is like riding a bicycle. To keep your balance, you must keep moving.
The stakes are immense, the task colossal, the time is short. But we may hope - we must hope - that man's own creation, man's own genius, will not destroy him.
I have no special talent. I am only passionately curious.
If you can't explain it simply, you don't understand it well enough.
Live your life... as though everything is a miracle.
I am truly a "lone traveler" and have never belonged to my country, my home, my friends, or even my immediate family, with my whole heart.