Proof techniques: Proof by Oddity

SAMPLE: To prove that horses have an infinite number of legs.
  1. Horses have an even number of legs.
  2. They have two legs in back and fore legs in front.
  3. This makes a total of six legs, which certainly is an odd number of legs for a horse.
  4. But the only number that is both odd and even is infinity.
  5. Therefore, horses must have an infinite number of legs.

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