Imperial Dictionary of Universal Biography/Volume 3/Zeno, the Eleatic
ZENO, the Eleatic philosopher, was born at Elea in Southern Italy about 490 b.c. He was the favourite pupil of Parmenides. In Plato's dialogue entitled Parmenides, it is related how Parmenides and Zeno came to Athens and held a philosophical conversation with Socrates, when the latter was a very young man. This must have been about 450 b.c. when Socrates was twenty years of age. Zeno was intimately associated with Parmenides, not only in the pursuits of philosophy, but also in the avocations of practical life. They took an active part in the administration of the affairs of their native city. Zeno is said to have stood forth as the resolute opponent of tyranny. Whether he was successful in his resistance, or perished in the attempt to obtain for his country a freer form of government, is a matter of uncertainty. The philosophy of Zeno differed but little from that of Parmenides. Both regarded the reason, and not the senses, as the organ of truth. Both argued for "Being," "the one," "the permanent," as that which alone existed; "the many" or "the changeable" being the opposite of the "one," was identical with "non-being." The only difference between the two philosophers seems to have been, that while Parmenides argued affirmatively that "the one," "the permanent," alone was; Zeno argued negatively that "the many"—the universe according to sense—was not. What is memorable in this philosophy is the attempt which it makes to signalize in the strongest terms the contrast or antithesis between sense and reason, and to exhibit the truths of reason in their most extreme opposition to the intimations of the senses. This opposition is principally set forth in those subtle puzzles of which Zeno was the author. One of these is the well-known "Achilles and the tortoise." If the tortoise has the start of Achilles by a hundred feet he can never overtake it; for when Achilles has advanced fifty feet, the tortoise will have advanced in a corresponding ratio, and so on in a progress in which the tortoise keeps the lead for ever. It is no solution of this paradox to show that Achilles does actually outstrip the tortoise. That, in fact, is the very circumstance which occasions the difficulty, for if he did not overtake it there would be no contradiction in the case. The same argument strikes at the possibility of all motion. Motion which is true in point of fact, is shown to be impossible on grounds of reason; for the shortest space is infinitely divisible, and therefore a body in passing from one point to another must traverse infinity, which it cannot possibly do. The only solution of these puzzles is to be found in the philosophy, which has for its principle "the unity of contraries."—J. F. F.