Ralph Waldo Emerson...
"To believe your own thought,-to believe that what is true for you, in your private heart, is true for all men,-that is genious. Familiar as the voice of the mind is to each, the highest merit we ascribe to Moses, Plato, and Milton, is, that they set at nought books and traditions, and spoke not what other men, but what they thought.-Yet this principle, in practical life as arduos as in the intellectual, may serve for the whole distinction betwixt men. It is the harder because you will always find those who think they know what is your duty better than you know it yourself. It is easy in the world to live after the world's opinion. It is easy in solitude to live after our own. But the great man is he who in the midst of the crowd keeps with perfect sweetness the independence of solitude."