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Philosophy

Relevance Logic and the Critique of Classical Entailment

Quick fact

In classical logic, the argument 'The moon is made of cheese; therefore, 2+2=5' is perfectly valid, because material implication treats any implication with a false antecedent as true.

Why this is interesting

Have you ever heard that a false statement implies anything? In classical logic, that's true—but it seems to make nonsense of reasoning. How can logic allow such irrelevant conclusions?