---
title: Theories of Truth
sort: 150
section-id: epistemology
description: Correspondence, coherence, pragmatist, and deflationary theories of truth.
language: en
---

# Theories of Truth

What is truth? The question seems either trivially easy or impossibly hard. Everyone knows that to say something true is to say how things are. And yet when we ask what this "correspondence" between language and world consists in, or whether there might be truths that do not correspond to any independent reality, we find ourselves in deep philosophical waters.

## The Correspondence Theory

The *correspondence theory of truth* is the classical answer: a proposition (or belief, or statement) is true if and only if it corresponds to the facts ^[Aristotle, *Metaphysics*, 1011b26-28]. To say that snow is white is to say something true, because it corresponds to the fact that snow is white.

The appeal of this theory is its fidelity to common sense. When we assert something, we are attempting to describe how things are, and truth is the property of succeeding in that attempt.

The challenge is making "correspondence" precise. Early twentieth-century philosophy developed the *picture theory of meaning* (Wittgenstein's *Tractatus*, Russell's logical atomism) on which propositions picture facts by sharing their logical structure ^[Wittgenstein, L., *Tractatus Logico-Philosophicus*, 1921, §2.15; Russell, B., "The Philosophy of Logical Atomism", *Monist* 28, 1918]. This was technically ambitious but ultimately abandoned.

The central difficulty for correspondence theories is the nature of *facts*. Are facts mind-independent features of the world? If so, what exactly are they, and how do they differ from merely true propositions? The proliferation of suspect entities (negative facts, disjunctive facts, mathematical facts) has made many philosophers wary.

## The Coherence Theory

The *coherence theory* identifies truth with coherence — membership in a system of beliefs that are mutually consistent, mutually supporting, and comprehensive ^[Bradley, F.H., *Essays on Truth and Reality*, 1914]. On this view, a belief is true not because it corresponds to some external fact but because it coheres with the overall system of beliefs.

The coherence theory is associated with British idealism (Bradley, Bosanquet) and has been influential in anti-realist philosophy more generally. Its appeal lies in removing the mysterious "correspondence" relation: truth is an internal relation among beliefs, not a relation between thought and world.

Critics raise two main objections. First, coherence is not sufficient for truth: many consistent, mutually supporting sets of beliefs are simply false. The elaborate beliefs of a deeply mistaken scientific tradition may be perfectly coherent. Second, coherence is not necessary: isolated beliefs can be true without being embedded in a rich coherent system.

## Pragmatist Theories

William James and John Dewey developed *pragmatist* theories of truth that identified truth with what "works" — what is expedient to believe, what guides successful action ^[James, W., "Pragmatism's Conception of Truth", in *Pragmatism*, 1907; Dewey, J., *Logic: The Theory of Inquiry*, 1938].

James's formulation is the most quotable: "True ideas are those that we can assimilate, validate, corroborate and verify. False ideas are those that we cannot."

Pragmatism has been persistently misread as claiming that truth is whatever we find convenient to believe, or that powerful people's beliefs are therefore true. More charitably, pragmatism is the claim that our concept of truth is tied to the role beliefs play in guiding inquiry and action: there is no coherent notion of truth that is entirely divorced from human practice.

The strongest objection is that some truths are inaccessible to human inquiry — truths about the distant past, truths about microscopic phenomena not yet observed. If truth is tied to what we could in principle verify, we seem to be claiming that there are no truths about such matters, which is implausible.

Peirce's more sophisticated version identified truth with what ideal inquiry would converge on in the long run ^[Peirce, C.S., "How to Make Our Ideas Clear", *Popular Science Monthly* 12, 1878]. This avoids the problem of currently inaccessible truths but introduces a counter-factual notion of "ideal inquiry" that is difficult to cash out.

## The Deflationary Theories

*Deflationary theories* — including Ramsey's *redundancy theory*, Quine's *disquotational theory*, and Horwich's *minimalism* — hold that "is true" adds nothing to a proposition ^[Ramsey, F.P., "Facts and Propositions", *Proceedings of the Aristotelian Society* Supp. Vol. 7, 1927; Horwich, P., *Truth*, Blackwell, 1990].

To say "it is true that snow is white" is simply to say "snow is white." The predicate "is true" serves a logical function — enabling us to endorse propositions without repeating them, to quantify over propositions ("everything she said is true") — but there is no deep property of *truth* to be analysed.

The T-schema captures the deflationist insight: for any sentence S, "'S' is true if and only if S." There is nothing more to truth than this biconditional schema.

Deflationists must explain how the truth predicate can do its logical work without denoting a substantive property. Critics also note that scientific realism seems to require a robust notion of truth — the success of science is best explained by the approximate truth of scientific theories — and deflationists have struggled to accommodate this.

## Truth and Language

The relationship between truth and language raises further questions. Alfred Tarski's semantic theory of truth ^[Tarski, A., "The Concept of Truth in Formalized Languages", 1935] provided a technically rigorous account for formal languages: "Snow is white" is true in language L if and only if snow is white. For natural languages, which are semantically open, Tarski's approach encounters the *Liar paradox* ("This sentence is false") and related self-referential difficulties.

Contemporary philosophy of language has explored truth-conditional semantics (meaning just is truth conditions), pluralism about truth (different truth predicates for different domains — factual, moral, mathematical), and relativism (truth relative to standards or contexts).

The debate about truth intersects with debates about realism and anti-realism, metaphysics, and the philosophy of language. It is one of the crossroads of philosophy — a place where multiple independent routes converge.
