A demon asks: would you live this exact life, every joy and pain, infinite times over?

Nietzsche imagined a demon proposing the ultimate test: everything that has happened to you, down to the smallest detail, must recur again and again, forever, in the same order. He asks whether the thought would crush you or make you fall to your knees in gratitude — calling it 'the greatest weight,' a measure of how much you actually love the life you have.

— Friedrich Nietzsche, The Gay Science — 1882, section 341
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