"I hope our wisdom will grow with our power, and teach us, that the less we use our power the greater it will be." (Thomas Jefferson)

and perhaps my all-time favorite quote ever:

"I never submitted the whole system of my opinions to the creed of any party of men whatever, in religion, in philosophy, in politics or in anything else, where I was capable of thinking for myself.  Such an addiction is the last degradation of a free and moral agent.  If I could not go to Heaven but with a party, I would not go there at all."  (Thomas Jefferson)