Neither the credibility of historians nor the acuity of our minds nor both jointly is capable of accurately judging to select a viable candidate. Also, the vicissitudes of the definition of greatness and the prohibition of discussing religion add further difficulties.

If I had sufficient self esteem I might nominate the person who invented spinning thread out of short fibers. Impressive!!!

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For those inclined to oppose human meddling with the structure of the universe or the composition and configuration of objects and groups of objects within the universe, consider:
Whether there is a limit to the magnitude of a modulation of chaos below which order remains invariant? Or, is order but a fiction invented by perspectives applied over finite, however large, time intervals?