Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."
"I live in that solitude which is painful in youth, but delicious in the years of maturity."
"In my experience, the best creative work is never done when one is unhappy."
"I believe that a simple and unassuming manner of life is best for every one, best for both the body and the mind."
"If I had my life to live over again, I would elect to be a trader of goods rather than a student of science. I think barter is a noble thing."