Scientifically speaking, a butterfly is at least as mysterious as a superstring. When something ceases to be mysterious it ceases to be of absorbing interest to scientists. Almost all things scientists think and dream about are mysterious.

Freeman Dyson (1923–2020) English-American theoretical physicist, mathematician, futurist

Infinite in All Directions, Part 1, ch. 2 “Butterflies and Superstrings” (1988)
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Based on his Gifford Lectures, Aberdeen, Scotland (Apr-Nov 1985).