"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."

i've heard this quote before but just now learned that it was written by Fitzgerald in his essay "The Crack-Up", written at the very end and lowpoint of his career; a raging alcoholic and washed-up writer living alone in a dollar-a-day hotel, financially and emotionally bankrupt while Zelda was by this time permanently institutionalized.