Aristotle called him the inventor of dialectic. His paradoxes contributed to development of logical and mathematical rigor. Appears as a character in Plato's Parmenides . Zeno promoted belief in The One over The Many, and tried to show inconsistencies in the latter. It is possible that Zeno was arguing against Pythagoreans.
Any unit has magnitude.
Any unit is infinitely divisible. Any unit is indivisible. Either 2 or 3 contradicts 1. Student of Parmenides, invented paradoxes to support P's monist position. All his arguments were reductios.