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Philosophy

The Logic of Presupposition and Presupposition Failure

Quick fact

Presupposition failure occurs when a statement's background assumption is false, causing the sentence to have no truth value at all—neither true nor false—rather than simply being false. For example, 'The present king of France is bald' is not false; it's meaningless in a technical sense because there is no king of France to refer to.

Why this is interesting

Have you ever said something and been understood even though your words didn't quite match reality? What if the sentence 'The present king of France is bald' isn't simply false—but somehow broken?