"Hallucinogenic plants act as enzymes which stimulate imagination."

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Humans! They lived in a world where the grass continued to be green and the sun rose every day and flowers regularly turned into fruit, and what impressed them? Weeping statues. And wine made out of water! A mere quantum-mechanistic tunnel effect, that'd happen anyway if you were prepared to wait zillions of years. As if the turning of sunlight into wine, by means of vines and grapes and time and enzymes, wasn't a thousand times more impressive and happened all the time.

— Terry Pratchett