Here's a couple of quotes I quite like... the first, I think, falls into the "words to live by" category. The second, just a nice quote that illustrates the humility of the man.
"If you are out there shooting, things will happen for you. If you're not out there, you'll only hear about it." - Jay Maisel
"If I knew how to take a good photograph, I'd do it every time." - Robert Doisneau