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LESSON 1 · The Logic of Arguments

Three Essential Parts

Every syllogism has a fixed anatomy:

  • Major premise — a general rule: "All birds have feathers"
  • Minor premise — a specific case: "A penguin is a bird"
  • Conclusion — the necessary result: "Therefore, a penguin has feathers"

Structure matters more than content. You can build a valid syllogism on false premises: "All cats can fly. Whiskers is a cat. Therefore, Whiskers can fly." The logic is flawless even though the conclusion is nonsense. Of the 256 possible arrangements, only 24 are valid forms.