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Philosophy

Philosophy Language Semantic Theory Of Truth

Quick fact

Alfred Tarski showed that for languages like arithmetic, truth can be defined purely in terms of satisfaction—a relation between sentences and objects—without using any undefined notion of truth, thus avoiding the liar paradox.

Why this is interesting

Have you ever said 'This sentence is false'? It's a paradox that makes truth seem impossible to pin down. Yet logicians found a way to define truth without falling into that trap—by learning to talk about language itself.