zeno's paradox
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The ancient greek philosopher Zeno was a hell of a trouble maker as far as philosophers go. The only reason Zeno's name has survived the millenia since his death in greece is that he asked a question people couldn't answer. We know of soccrates and plato because they philosophized about different things and thought up philosophical explanations for the things we observe in the world. Aristotle thought that rocks fall to the earth when dropped because things seek their rightful places and Democritus thought that the world must be made up of small particles and empty space because there is room to move around. That some of these ideas has met with more sucesss than others is only natural, Aristotles concept of gravity was replaced by newton and the horror vacui was eventually replaced by something distantly akin to Democritus theory of a particulate world. The difference between aristotles failed theory of gravity and Democritus famous conjecture about atoms is not the soundness of their philosophical bases. Both theories are equally sound in the world of philosophy but the reason aristotles view has fallen into disfavor is that it does not seem to be the way the world works. Similarly the only reason Democritus has not sunk to anonymity is that his far fetched idea seems to have some bearing on how things act in the real world. It is interesting to note then that Zeno is famous for exactly the opposite reason that Democritus is. Zeno took a few seemingly sound philosophical assumptions and used them to logically prove something that was clearly at odds with the world of reality. Unlike Aristotle or Democritus Zeno was not trying to explain the world with philosophy rather he was using the real world to show that philosophy was not always reliable as a means to explaining the world. Zenos paradox is one of the most famous of all time because for centuries philosophers thought about it and were unable to poke a hole in Zeno's reasoning. The paradox is this you can never walk across a room. In order to cross any distance you must first cross half that distance. But in order to cross the remaining distance across the room you must cross half the remaining distance. To cross that distance you must cross half of the remainder of that and so on ad infinitum. Zeno's logic was this that since you would need to cross an infinite number of divisions in order to cross the room and since it takes you a non zero amount of time to traverse each distance when we try to cross the room we will find that it takes an infinite amount of time and therefore we will never get to the other side. The paradox is obviously false and so Zenos paradox strictly speaking is a misnomer however it is no less intriguing for its obvious incorrectness. Quite the contrary it is interesting because it is a logical explanation of an effect that we don't observe in the real world.
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