Zeno supported Parmenides' contention that the universe is a plenum, a single substance, a oneness, without boundary or separation, although the world appears diversified to our fallible senses. A plenum is space totally filled with matter; the opposite to a vacuum.

Zeno's intention was to discredit the senses, which he sought to do through a series of paradoxes on time and space.

Zeno asserts that a runner cannot reach a goal because, in order to do so, he must traverse a distance; but he cannot traverse that distance without first traversing half of it, and so on, ad infinitum. Because an infinite number of bisections exist in a spatial distance, one cannot travel any distance in finite time - however short the distance or great the speed. This argument, like several others of Zeno's, is intended to demonstrate the logical impossibility of motion.

The argument is, then, that the evidence of the senses should be rejected in favour of the evidence of rationality and logic. We discover reality not by examining it, but by thinking logically.