Zeno of Elea (circa 450 BC) is credited with creating several famous paradoxes, but by far the best known is the paradox of the tortoise and Achilles. A fleet-of-foot Achilles is unable to catch a plodding tortoise which has been given a head start, since during the time it takes Achilles to catch up to a given position, the tortoise has moved forward some distance. But this is obviously fallacious since Achilles will clearly pass the tortoise!