Logic is a system of reasoning for reaching correct conclusions about concepts and for assessing a conclusion that has been reached. It is closely related to mathematics. Aristotle developed the ideas of logic considerably, creating a formula called a syllogism (SIL-oh-jiz-uhm), which consists of a general statement, a specific statement, and a conclusion. The most famous example is "All men are mortal. Socrates is a man. Therefore, Socrates is mortal."
Like math, logic has nothing to do with anything outside itself. When adding two plus two, it does not matter if the "two" refers to two apples or two hand grenades. Similarly, logic can be applied correctly to untrue statements.
No one illustrated this fact better than Zeno of Elea, though that was not his purpose. Setting out to prove that motion, and therefore change, were impossible, he put forward the four paradoxes of motion.
Each paradox is a little story, each slightly different, and together they make up the first set of brainteasers in history—puzzles that have delighted and irritated children and adults alike.
In one paradox, Zeno referred to an arrow being shot from a bow. At every moment of its flight, it could be said that the arrow was at rest within a space equal to its length. Though it would be some 2,500 years before slow-motion photography, in effect he was asking his listeners to imagine a snapshot of the arrow in flight. If it was at rest in that snapshot, and at every other moment it was supposedly in motion, then when did it actually move?
World History
