Truth-Conditional Semantics

Truth-Conditional Semantics is the theory that the meaning of a sentence is given by the conditions under which it would be true — its truth conditions. To know what a sentence means is to know what the world would have to be like for the sentence to be true. This approach, pioneered by Gottlob Frege and developed by Alfred Tarski into the formal apparatus of model-theoretic semantics, has been the dominant framework in philosophy of language and linguistics for over a century.

The central intuition is deceptively simple. The sentence 'Snow is white' means what it means because it is true if and only if snow is white. Generalizing this pattern: for any declarative sentence S, to know its meaning is to know the proposition it expresses, and to know the proposition is to know the possible worlds (or models) in which it holds. Bertrand Russell's theory of descriptions and the Vienna Circle's verificationism both operated within this framework, even when they sought to restrict it to empirically accessible truths.

The deepest challenge to truth-conditional semantics comes from Michael Dummett's anti-realist argument. If the meaning of a sentence is its truth conditions, and those conditions may obtain beyond any possible investigation, then meaning becomes a private relation between a sentence and an unknowable state of affairs — not something that can be learned, taught, or displayed in linguistic behavior. The anti-realist claims that truth-conditional semantics substitutes a metaphysical picture for a semantic theory: it tells us what meaning would look like if minds were infinite, not what meaning is for finite speakers embedded in finite practices.

The debate between truth-conditional and verification-conditional semantics is not merely a technical dispute about semantic frameworks. It is a dispute about whether language is primarily a map onto a pre-given reality or a tool for coordinating finite cognitive agents. The truth-conditional theorist sees language from God's perspective; the anti-realist sees it from the speaker's. Which perspective is the right one for philosophy depends on whether you believe that semantics should describe an idealized relation between sentences and worlds, or explain how actual human beings actually understand one another.