Attention to details is important not just in math.

"In a race, the quickest runner can never over­take the slowest, since the pursuer must first reach the point whence the pursued started, so that the slower must always hold a lead."

Here with the word "never", do we mean there is no point in time when the pursuer reach the pursued, or do we mean in steps of this successions?

Because if we mean in time, the sentence doesn't state anything about time. So in case we need to assume something about the time and demonstrate either that this point exists or not.

If we mean in the steps, yes this sentence demonstrate that there is not a finite number of steps in the succession where the pursuer reaches the pursued. Interesting but not paradoxical.