Zeno's Other Attacks

The arrow was just one weapon in Zeno's arsenal against movement:

• Achilles and the Tortoise — Achilles must first reach where the tortoise was, but by then it has moved on, so he can never catch up
• The Dichotomy — to cross a room you must first cross half, then half of that, and so on without end
• The Stadium — rows moving in opposite directions create contradictions about relative speed

All four paradoxes attack the same idea: that infinite divisions of space and time should make movement impossible. The fact that things obviously move is exactly what makes these puzzles rather than simple mistakes.