The flame of conception seems to flare and go out, leaving man shaken, and at once happy and afraid. There’s plenty of precedent of course. Everyone knows about Newton’s apple. Charles Darwin said his Origin of Species flashed complete in one second, and he spent the rest of his life backing it up; and the theory of relativity occurred to Einstein in the time it takes to clap your hands. This is the greatest mystery of the human mind — the inductive leap. Everything falls into place, irrelevancies relate, dissonance becomes harmony, and nonsense wears a crown of meaning. But the clarifying leap springs from the rich soil of confusion, and the leaper is not unfamiliar with pain.

- John Steinbeck, Sweet Thursday