Suppose that the swift Achilles is having a race with a tortoise. Since the tortoise is much slower, she gets a head start. When the tortoise has reached a given point a, Achilles starts. But by the time Achilles reaches a, the tortoise has already moved beyond point a, to point b. And by the time Achilles reaches b the tortoise has already moved a little bit farther along, to point c. Since this process goes on indefinitely, Achilles can never catch up with the tortoise.

How can this be?

Taken from - http://members.aol.com/kiekeben/zeno.html

this is really something of a approaching a limit. Each time Achilles reaches the point where the tortoise was last, the tortoise has moved on. This will not actually go on forever but the idea is that Every time Achilles reaches the spot, the tortoise doesn't make it quite as far from it as the last time. This will go on in distance wise forever, but Achilles will pass the tortoise when he reaches the limit of this distance. Even though he reached the limit, the mathematics of the distances could be computed as if he didn't.

Posted by Jon on 2003-04-11 06:53:27