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Philosophy

Relevance Logic and Relevance Logic Systems

Quick fact

Relevance logic was developed to fix the 'fallacies of relevance' in classical logic. Logicians like Wilhelm Ackermann and Alan Anderson and Nuel Belnap created systems where an implication is true only if the antecedent and consequent genuinely share content.

Why this is interesting

Have you ever heard a 'valid' argument that still feels completely wrong, like 'If grass is green, then unicorns exist'? In classical logic, that statement is actually true—but does that make it logical?