Was reading the New Yorker review of The Great Gatsby and came across this Fitzgerald quote from his essay The Crack-Up:
Before I go on with this short history, let me make a general observation—the test of a first-rate intelligence is the ability to hold two opposed ideas in the mind at the same time, and still retain the ability to function. One should, for example, be able to see that things are hopeless and yet be determined to make them otherwise.
I like that.