Love is not the stupidest thing a man does, but it cannot be blamed on gravity.
An oligarchy of private capital cannot be effectively checked even by a democratically organized political society because under existing conditions, private capitalists inevitably control, directly or indirectly, the main sources of information.
A person who never made a mistake never tried anything new.
The most important question a person can ask is, "Is the Universe a friendly place?
I learned many years ago never to waste time trying to convince my colleagues.
The most important decision we make is whether we believe we live in a friendly or hostile universe.