Jump to Content Jump to Main Navigation

Philosophy Truth
by
Pascal Engel

Introduction

The problem of the nature of truth is Janus-faced. On the one hand, it seems to be so metaphysically profound that it is forever hidden to us and not worth caring about, as Pontius Pilate’s jesting question, “What is truth?” (John 18:38), implied. On the other hand, truth seems to be, as René Descartes said, “so transcendentally clear that it is impossible to ignore” and thus not really necessary to investigate philosophically. What can be simpler, as Aristotle said, than “to say of what is that it is not, or of what is not that it is, is false, while to say of what is that it is, and of what is not that it is not, is true”? At the same time what can be more complex than spelling out why there is this mysterious relation of truth between words and things? The very attempt to say what this property of truth is seems to take us to the highest reaches of metaphysical thought and to raise almost all of the issues of philosophy: those of the nature of knowledge, of the mind’s dependence on or independence of reality, and of language and its relation to the world. Indeed, philosophers have elaborated a number of complex theories of truth, from the classical correspondence theory to the coherence and pragmatist theories. But even a “simple” or, in modern terms, “deflationary” or “minimalist,” theory of truth is not so simple to spell out.

General Overviews

A beginner to the subject can still benefit from the remarkably clear remarks on truth in Russell 1912. A comprehensive overview of the late 20th-century theories is in Kirkham 1992. Wright 1999 is an excellent map that sketches also the author’s own “minimalist” conception. The best overall treatment is Künne 2003.

  • Kirkham, Richard. Theories of Truth. Cambridge, MA: MIT Press, 1992.

    Save Citation »Export Citation »E-mail Citation »

    Although it does not deal with debates later than 1990, this introduction will still be beneficial to the general reader, in particular for its clear and compressed treatment of Alfred Tarski’s semantic theory and of its implications.

    Find this resource:

  • Künne, Wolfgang. Conceptions of Truth. Oxford: Oxford University Press, 2003.

    DOI: 10.1093/0199241317.001.0001Save Citation »Export Citation »E-mail Citation »

    This is the most systematic work on the philosophy of truth. It combines remarkable and unfailing historical scholarship, from Gottfried Wilhelm Leibniz to early analytic philosophy, with great care in discussion of the contemporary arguments. The author defends a “modest” conception that has many affinities with deflationism but flies away from the pluralistic tendencies present in it.

    Find this resource:

  • Russell, Bertrand. Problems of Philosophy. Oxford: Oxford University Press, 1912.

    Save Citation »Export Citation »E-mail Citation »

    The extraordinary thing about Russell’s treatment of truth is that a century later it is still, despite its simplifications and time-bound features, the best introduction to the subject. Russell defends a correspondence theory of truth combined with an account of judgment that has influenced Ludwig Wittgenstein and analytic philosophy ever since.

    Find this resource:

  • Wright, Crispin. “Truth: A Traditional Debate Reviewed.” Canadian Journal of Philosophy 24 (1999): 31–74.

    Save Citation »Export Citation »E-mail Citation »

    A remarkable survey article that gives a useful map of the commitments of theories of truth and sketches the authors’ own “minimalist” views, developed further in Wright 1992 (see Deflationism and Minimalism). Reprinted in Simon Blackburn and Keith Simmons, eds., Truth (Oxford: Oxford University Press, 1999), pp. 233–238.

    Find this resource:

Textbooks

Engel 2002 and Volpe 2005 can be used as introductions to the main contemporary philosophical views. No one interested in these issues can go very deep without a good understanding of the formal and logical background of these discussions. Gabbay and Guenthner 2001–2005 is a very useful guide.

  • Engel, Pascal. Truth. Chesham, UK: Acumen, 2002.

    Save Citation »Export Citation »E-mail Citation »

    An opinionated introduction that tries to steer midway between alethic pluralism and a full-blown realist view. It defends a form of minimal realism according to which truth obeys a set of syntactic constraints but incorporates a substantive norm involving beliefs and assertions aiming at knowledge in the realist sense.

    Find this resource:

  • Gabbay, Dov, and Franz Guenthner. Handbook of Philosophical Logic. 3d ed. Dordrecht, The Netherlands: Kluwer, 2001–2005.

    Save Citation »Export Citation »E-mail Citation »

    A remarkable set of articles on truth and its logical underpinnings in the varied landscape of contemporary logical systems. It is particularly strong on nonclassical logics and semantics for modal logics.

    Find this resource:

  • Volpe, Giorgio. Teorie della verita. Milan: Guerini, 2005.

    Save Citation »Export Citation »E-mail Citation »

    A comprehensive account of the contemporary view that provides useful surveys of the main classical positions and emphasizes the philosophy of language aspects of the debate (assertion, truth bearers, truth and meaning).

    Find this resource:

Anthologies

Two good anthologies are Blackburn and Simmons 1999 and Lynch 2001. Blackburn and Simmons 1999 contains the classics of the analytic tradition, and Lynch 2001 contains in addition the classical texts on truth by Martin Heidegger, James, and Charles Sanders Peirce as well as more recent work not in Blackburn and Simmons 1999. Schantz 2002 contains more recent material.

  • Blackburn, Simon, and Keith Simmons, eds. Truth. Oxford: Oxford University Press, 1999.

    Save Citation »Export Citation »E-mail Citation »

    The best short anthology, containing a judicious choice of the seminal papers by F. H. Bradley, Bertrand Russell, Gottlob Frege, F. P. Ramsey, Ludwig Wittgenstein, Alfred Tarski, W. V. O. Quine, John Langhaw Austin, P. F. Strawson, Michael Dummett, Paul Horwich, Hartry Field, and Donald Davidson as well as an article on paradoxes by one of the editors.

    Find this resource:

  • Lynch, Michael P., ed. The Nature of Truth. Cambridge, MA: MIT Press, 2001.

    Save Citation »Export Citation »E-mail Citation »

    A good collection (more than 790 pages) covering a wide range of authors and topics, from classical articles in analytic philosophy to the Hegelians and the pragmatists (Blanchard, James, Charles Sanders Peirce) as well as the postmodernists (Richard Rorty, Michel Foucault) and the protagonists of the debates about pluralism about truth (Crispin Wright, Paul Horwich, Michael P. Lynch).

    Find this resource:

  • Schantz, Robert, ed. What Is Truth? Berlin: de Gruyter, 2002.

    Save Citation »Export Citation »E-mail Citation »

    This collection contains articles by David Armstrong, Wiggins, D. A. Grover, Brandom, Marian David, Alston, and Devitt that deal with both the deflationist views and the most substantive views based on truth maker’s theory.

    Find this resource:

Historical Background

The historical background of truth can be broken down into two time periods. See Ancient and Medieval Views and Modern and Contemporary Views.

Ancient and Medieval Views

Ancient philosophers have discussed truth ever since Parmenides (Barnes 2009), and medieval philosophers (Buridan 1966) did not ignore the paradoxes of truth and reference. Aristotle’s conception contains echoes both the idea that truth is correspondence to facts and the idea that it is a simple and undefinable concept (Aristotle 1984). For an extensive commentary on Aristotle’s views and a confrontation with contemporary views, see Crivelli 2004. The traditional definition of truth as adequatio rei et intellectus comes from Thomas Aquinas’s Quaestiones disputatae de veritae (Aquinas 1952).

  • Aquinas, Thomas. Disputed Questions on Truth. Chicago: Regnery, 1952.

    Save Citation »Export Citation »E-mail Citation »

    Aquinas’s definition of truth as adaequatio of res and intellectus has shaped the versions of the correspondence doctrine for centuries.

    Find this resource:

  • Aristotle. “Metaphysics”. In The Complete Works of Aristotle. By Aristotle. Translated and edited by Jonathan Barnes. Princeton, NJ: Princeton University Press, 1984.

    Save Citation »Export Citation »E-mail Citation »

    Aristotle’s views on truth show how intricate are the issues with which the tradition deals: logical, semantic, epistemological. Book B is a dialectical discussion of many of them, inspired by the Sophists’ challenge (especially Protagoras’s relativism).

    Find this resource:

  • Barnes, Jonathan. Truth, Etc. Oxford: Oxford University Press, 2009.

    Save Citation »Export Citation »E-mail Citation »

    A remarkable account of truth in ancient logic and philosophy. Covering a wealth of material, it discusses the problems of the nature of truth bearers, of inference, and of the essence of logic from Plato to Hellenistic philosophy.

    Find this resource:

  • Buridan, Jean. Sophisms on Meaning and Truth. Translated by T. K. Scott. New York: Appleton-Century-Crofts, 1966.

    Save Citation »Export Citation »E-mail Citation »

    Among the vast medieval literature on “sophismata” (logical problems set up by dialecticians), the French 14th-century logician Jean Buridan’s sophisms on meaning and truth develop paradoxes of self-reference, such as the liar paradox, which were to play a lasting role in philosophy.

    Find this resource:

  • Crivelli, Paolo. Aristotle on Truth. Cambridge, UK: Cambridge University Press, 2004.

    DOI: 10.1017/CBO9780511482496Save Citation »Export Citation »E-mail Citation »

    The best and virtually the only monograph entirely devoted to Aristotle’s views on truth. It combines expert scholarship with a remarkable confrontation of Aristotle’s views with the contemporary ones.

    Find this resource:

Modern and Contemporary Views

The modern tradition takes two different directions. On the one hand, the Aristotelian tradition of correspondence developed through the Austrian tradition of Bolzano 1985, Brentano 1966 (originally published in 1930), and Husserl 1973 and joined forces with the British tradition through Moore 1993 and Bertrand Russell, finding its most influential 20th-century expression in Ludwig Wittgenstein’s Tractatus logico-philosophicus (Wittgenstein 1961). On the other hand, philosophers such as Benedict de Spinoza and Gottfried Wilhelm Leibniz developed coherence theories (see Rauzy 2001), although the contemporary expression of coherence theories is mostly in Bradley 1914. Immanuel Kant called the correspondence view the “nominal” definition of truth and defended an idealist and epistemic conception of truth. Bradley 1914 defends the most influential version of the coherence theory. The Peirce 1958 conception of truth as the end of inquiry is on the idealist side too, and it is only with James that it is equated with utility or with what it is satisfactory to believe. Frege 1956 is an early expression of the view that the truth predicate “is redundant and does not add anything to the mere assertion of a sentence.”

  • Bolzano, Bernhard. Wissenschaftslehre. 4 vols. Stuttgart: Frommann-Holzboog, 1985.

    Save Citation »Export Citation »E-mail Citation »

    Bolzano’s philosophy of truth is part and parcel of his conceptions of judgment, propositions, and knowledge that are not only the source of many contemporary doctrines (Edmund Husserl, F. Brentano, Gottlob Frege, Ludwig Wittgenstein) but also have anticipated them in astonishingly precise ways. Originally published in 1837 (Sulzbach, Germany: Seidel).

    Find this resource:

  • Bradley, F. Essays on Truth and Reality. Oxford: Clarendon, 1914.

    Save Citation »Export Citation »E-mail Citation »

    Bradley formulated the most explicit coherence theory of truth, which was to be attacked by Bertrand Russell. It has been argued that it had strong affinities with the identity theory.

    Find this resource:

  • Brentano, F. The True and the Evident. London: Routledge, 1966.

    Save Citation »Export Citation »E-mail Citation »

    English translation of Wahrheit und Evidenz (Leipzig: Meiner, 1930). Brentano’s conception of truth is a realistic theory but a noncorrespondentist one. He claims correspondence to be only a “nominal” notion and ties truth to the exercise of judgment: a judgment is true if it is evident and about existing things, false or otherwise.

    Find this resource:

  • Frege, Gottlob. “The Thought.” Mind 65 (1956): 289–311.

    Save Citation »Export Citation »E-mail Citation »

    Frege’s conception of truth, articulated in this classical article (originally “Der Gedanke,” in Kleine Schriften [Hildesheim, Germany: Olms, 1914]), is overtly realist in his emphasis on the primacy of judgment and the objective and timeless nature of truth but also has deflationist overtones in his claim that “‘P’ is true” has the same meaning as “P.”

    Find this resource:

  • Husserl, Edmund. Logical Investigations. Translated by J. N. Findlay. London: Routledge, 1973.

    Save Citation »Export Citation »E-mail Citation »

    English translation of Logische Untersuchungen (Halle, Germany, 1900). Husserl’s conception has much in common with F. Brentano’s: a true judgment is one that one would judge evident in ideal circumstances. But his conception of truth is also a correspondence one, since he considers true judgments to correspond to facts and states of affairs.

    Find this resource:

  • Moore, George Edward. “The Nature of Judgment.” In G. E. Moore: Selected Writings. By G. E. Moore. Edited by Thomas Baldwin, 1–19. London: Routledge, 1993.

    Save Citation »Export Citation »E-mail Citation »

    Moore’s early views on judgment express an identity theory of truth that has affinities with F. Bradley’s, but its insistence on propositions as being fully objective and real is a kind of extreme realism, which strongly influenced Bertrand Russell’s early views. Originally published in Mind 9 (1899): 176–193.

    Find this resource:

  • Peirce, Charles Sanders. “How to Make Our Ideas Clear.” In Collected Papers. Vol. 5. Edited by Arthur W. Burks and Paul Weiss. Cambridge, MA: Harvard University Press, 1958.

    Save Citation »Export Citation »E-mail Citation »

    Peirce’s classic article develops his two main doctrines: his pragmatism about belief as a disposition to act and his definition of truth as the limit of scientific inquiry. It is important to note that Peirce was not a pragmatist in that he did not define truth as utility. Reprinted in Lynch 2001 (see Anthologies).

    Find this resource:

  • Rauzy, Jean-Baptiste. La doctrine leibnizienne de la vérité: Aspects logiques et ontologiques. Paris: J. Vrin, 2001.

    Save Citation »Export Citation »E-mail Citation »

    Gottfried Wilhelm Leibniz’s views on truth are, according to this commentary, closer to what is known in the early 21st century as a coherentist view, a true judgment being a form of inherence of the predicate in the subject (praedicatum inest subjecto), ultimately grounded in God’s knowledge of substances.

    Find this resource:

  • Wittgenstein, Ludwig. Tractatus logico-philosophicus. Translated by D. F. Pears and B. F. McGuinness. London: Routledge, 1961.

    Save Citation »Export Citation »E-mail Citation »

    Although rooted within the Austrian tradition, Wittgenstein’s 1921 picture theory of language and his view of propositions as representing states of affairs and facts was the main inspiration for most correspondentist theories in the 20th century.

    Find this resource:

The Semantic Conception

Tarski 1983, on the concept of truth in formalized languages (published in Polish in 1933, in German in 1935, accessible in English in 1944 in a less technical version, and translated into English in 1952), was the first attempt at a formal definition of truth for a logical language and has deeply influenced logic and philosophy. Tarski sets out a “material adequacy” condition, known as “convention T,” to the effect that a semantic theory for a logical language L must derive theorems of the form “S is true if and only if P,” and defines a hierarchy of languages to deal with the semantic paradoxes, such as the liar paradox (Carnap 1942). Tarski explicitly denies that his formal definition can account for truth in natural languages. It is only later, with Davidson 1967, that Tarski’s convention T was applied to natural languages. Quine 1986 is an influential version stressing the use of the predicate “true” as a device of “disquotation.” Field 1972 argues that Tarski’s theory is incomplete without a causal theory of reference.

  • Carnap, Rudolf. Introduction to Semantics. Cambridge, MA: Harvard University Press, 1942.

    Save Citation »Export Citation »E-mail Citation »

    Carnap was one of the first among the logical positivists to attract attention to the importance of Alfred Tarski’s formal work for philosophy and semantics. In this book he introduces Tarski’s work and formulates the principles of a formal treatment for natural and artificial languages.

    Find this resource:

  • Davidson, Donald. “Truth and Meaning.” Synthese 17 (1967): 304–323.

    DOI: 10.1007/BF00485035Save Citation »Export Citation »E-mail Citation »

    Davidson gave a new twist to Tarskian theories of truth by proposing that they serve contrary to Alfred Tarski’s original intentions—to explain meaning in a natural language by taking truth as primitive in an empirical theory. Reprinted in Donald Davidson, Inquiries into Truth and Interpretation (Oxford: Clarendon, 1984).

    Find this resource:

  • Field, Hartry. “Tarski’s Theory of Truth.” Journal of Philosophy 69 (1972): 347–375.

    DOI: 10.2307/2024879Save Citation »Export Citation »E-mail Citation »

    Defends the idea that a Tarskian truth definition does not give us any genuine theory of the reference of terms and investigates whether a causal theory of reference could supplement it. Reprinted in Field 2001 (see Deflationism and Minimalism).

    Find this resource:

  • Quine, W. V. O. Philosophy of Logic. 2d ed. Englewood Cliffs, NJ: Prentice-Hall, 1986.

    Save Citation »Export Citation »E-mail Citation »

    Quine formulates, on the basis of Alfred Tarski, a “disquotational” conception of truth according to which truth is a property of sentences in a language, the nature of which is exhausted by the schema “‘P’ is true if and only if P.”

    Find this resource:

  • Tarski, Alfred. Logic, Semantics, Metamathematics. 2d ed. Edited by J. Corcoran. Translated by J. H. Woodger. Indianapolis, IN: Hackett, 1983.

    Save Citation »Export Citation »E-mail Citation »

    Tarski’s seminal article, originally published in German (“Der Wahrheitsbegriff in den formalisierten Sprachen,” Studia Philosophica 1 [1936]: 261–405), is formulated in terms of the theory of classes. The 1944 article gives a more accessible presentation. Tarski pretends that his definition was metaphysically neutral and that it could serve the purposes of a physicalistic conception. But these claims have been disputed ever since (see Kirkham 1992 in General Overviews).

    Find this resource:

Contemporary Substantive Theories

The main “substantive” theories of truth, in the sense that they try to define truth in terms of other notions, are the correspondence theory, the coherence theory, and the pragmatist theory. But they can also be classified, according to the Dummett 1978 criterion (is truth verification transcendent or not?) as either realist (correspondence) or as antirealist or idealist (coherence, verificationism, and pragmatism). The correspondence theory says that truth is correspondence to the facts. But there are various ways to understand the bearers of truth (as sentences, judgments, contents, propositions, or statements) and various degrees of involvement to an ontology of facts or states of affairs. The minimal understanding of correspondence is in Austin 1979, which contains the author’s famous debate with P. F. Strawson (Strawson 2004). David 1994 and Vision 2004 develop and defend the correspondence theory against deflationist views, but they try to dispense with the notion of fact or of truth maker. A coherence theory of truth says that a belief is true if it belongs to a set of coherent beliefs. Verificationism about truth (not to be confused with verificationism about meaning) was defended by many logical positivists and by some pragmatists. A recent version of the coherence theory is Walker and Walker 1989. Pragmatist theories define truth more in terms of warranted assertibility, as did John Dewey, than in terms of utility. In Rorty 1979 the pragmatist theory is more a criticism of representationalism that has affinities with deflationism.

  • Austin, John Langhaw. “Truth.” Proceedings of the Aristotelian Society, supp. 24 (1979): 111–128.

    Save Citation »Export Citation »E-mail Citation »

    Austin defends an unorthodox correspondence theory according to which there are conventions of language relating words to the world. Reprinted in Philosophical Papers (Oxford: Oxford University Press, 1961), 117–133.

    Find this resource:

  • David, Marian. Correspondence and Disquotation: An Essay on the Nature of Truth. Oxford: Oxford University Press, 1994.

    Save Citation »Export Citation »E-mail Citation »

    A subtle analysis of the shortcomings of the disquotationalist conception and a defense of a form of correspondence theory without the use of the notion of fact.

    Find this resource:

  • Dummett, Michael. “Truth.” In Truth and Other Enigmas. By Michael Dummett, 1–24. Cambridge, MA: Harvard University Press, 1978.

    Save Citation »Export Citation »E-mail Citation »

    In this classic article, Dummett defends an antirealist conception of truth defined in terms of assertion conditions and rejects both the redundantist conception of truth and theories of meaning based on truth conditions. Originally published in Proceedings of the Aristotelian Society 29 (1959): 141–162.

    Find this resource:

  • Rorty, R. Philosophy and the Mirror of Nature. Princeton, NJ: Princeton University Press, 1979.

    Save Citation »Export Citation »E-mail Citation »

    Radicalizing W. B. O. Quine’s and Donald Davidson’s arguments about meaning, Rorty criticizes the correspondentist idea that our language could represent reality and proposes a form of pragmatism that has postmodernist overtones and rests upon a deflationist conception of truth.

    Find this resource:

  • Strawson, P. F. “Truth.” In Logico-Linguistic Papers. By P. F. Strawson, 147–164. Aldershot, UK: Ashgate, 2004.

    Save Citation »Export Citation »E-mail Citation »

    Strawson objects to Austin 1979, that the notion of fact is equivalent to that of a true proposition, and defends a version that is sometimes called the performative theory of truth, close to a form of deflationary or redundantist view. Originally published in Proceedings of the Aristotelian Society 24 (1950).

    Find this resource:

  • Vision, G. Veritas: The Correspondence Theory and Its Critics. Cambridge, MA: MIT Press, 2004.

    Save Citation »Export Citation »E-mail Citation »

    Tries to revive, against its contemporary critics, the classical correspondence conception.

    Find this resource:

  • Walker, Ralph, and R. C. S. Walker. The Coherence Theory of Truth: Realism, Anti-Realism, Idealism. London and New York: Routledge, 1989.

    Save Citation »Export Citation »E-mail Citation »

    A complete statement of the coherence conception along Kantian lines.

    Find this resource:

Deflationism and Minimalism

The most radical criticism of substantive theories is given by deflationist conceptions of truth. Deflationism says that truth has no essence and no explanatory role and is just a device of assertion. But deflationism comes in many varieties (see Hawthorne and Oppy 1997). In a sense Tarskian truth and the disquotational conception are forms of deflationism. The most radical view, inspired by Ramsey 1990, says that truth is only a redundant predicate that does not amount to more than the assertion of a sentence. It is elaborated in the “prosentential” conception of Williams 1976 and Grover 1992. For an elaboration of this kind of view, see Azouni 2006 (cited under Truth and Proof). The Horwich 1998 version of deflationism takes truth to be a property of propositions and defines it through the schema “the proposition that P is true = P.” Wright 1992 defends a form of “minimalism” that is compatible with a kind of pluralism, accepting that truth may differ from domain to domain (mathematics, ethics, physical objects, and so forth) but is more a form of minimal antirealism than a form of minimal realism. The Davidson 1996 view is often taken to be deflationist. Field 2001 defends a “nonfactualist” full-blown deflationist conception of truth.

  • Davidson, Donald. “The Folly of Trying to Define Truth.” Journal of Philosophy 93.6 (1996): 263–278.

    DOI: 10.2307/2941075Save Citation »Export Citation »E-mail Citation »

    Davidson claims that truth is an undefinable and primitive notion, but he rejects the idea that it has no substantial role to play. It serves as a posit within a theory for interpreting belief and meaning. Reprinted in Simon Blackburn and Keith Simmons, eds., Truth (Oxford: Oxford University Press, 1999).

    Find this resource:

  • Field, H. Truth and the Absence of Fact. Oxford: Oxford University Press, 2001.

    DOI: 10.1093/0199242895.001.0001Save Citation »Export Citation »E-mail Citation »

    A defense of deflationism combined with a nonfactualist view about two domains of discourse that are often considered to obey strong realist constraints: mathematics and epistemology.

    Find this resource:

  • Grover, D. A Prosentential Theory of Truth. Princeton, NJ: Princeton University Press, 1992.

    Save Citation »Export Citation »E-mail Citation »

    The “prosentential theory of truth” is an attempt to cope with the problem of propositional quantification by treating truth as a sentential operator rather than as a predicate. It says that “that’s true” is a prosentence functioning like a pronoun.

    Find this resource:

  • Hawthorne, O’Leary J., and G. Oppy. “Minimalism and Truth.” Noûs 31 (1997): 170–196.

    DOI: 10.1111/0029-4624.00041Save Citation »Export Citation »E-mail Citation »

    An excellent account of the various deflationist and minimalist theories.

    Find this resource:

  • Horwich, P. Truth. 2d ed. Oxford: Oxford University Press, 1998.

    DOI: 10.1093/0198752237.001.0001Save Citation »Export Citation »E-mail Citation »

    A very clear and influential exposition of deflationism. Horwich takes truth to be a “thin” property, obeying only the schema “the proposition that P is true = P” from which an infinity of instances can be derived. He shows how deflationism can accommodate most of the intuitions that are associated with substantive theories without having their commitments.

    Find this resource:

  • Ramsey, F. P. “Facts and Propositions.” In Philosophical Papers. Edited by D. H. Mellor, 34–51. Cambridge, UK: Cambridge University Press, 1990.

    Save Citation »Export Citation »E-mail Citation »

    Written in 1927. Ramsey gave the first systematic exposition of the deflationist conception of truth, according to which there is no more to “it is true that P” than the assertion of P, and he raised the problem of the propositional reference in “blind ascriptions,” such as, “All that the Pope says is true.” He claimed that the problem of the nature of truth had to give way to the problem of the nature of assertion.

    Find this resource:

  • Williams, C. J. F. What Is Truth? Cambridge, UK: Cambridge University Press, 1976.

    DOI: 10.1017/CBO9780511753527Save Citation »Export Citation »E-mail Citation »

    Gives the first explicit statement of the “simple” theory of truth according to which “it is true that P” amounts to the assertion of P. The main difficulty it must solve is quantification into blind ascriptions, such as, “For all P if S said that P, then P” where the variable “P” has a different role in each of its occurrences.

    Find this resource:

  • Wright, Crispin. Truth and Objectivity. Oxford: Oxford University Press, 1992.

    Save Citation »Export Citation »E-mail Citation »

    In this influential work, Wright defends a kind of “inflated” deflationism (truth register a norm distinct from assertion) that takes an antirealist conception as the default option and argues that, depending of the commitments of various domains of discourse, it can be understood as correspondence, coherence, or “superassertibility” (a form of ideal assertibility).

    Find this resource:

Truth and Proof

A fundamental issue is whether logic is a matter of inference, deduction, and proof or a matter of truth. David Hilbert’s program in mathematics emphasized the former through an attempt to prove the consistency of arithmetic. Gerhard Gentzen did so too by formulating first-order logic as a system of rules of inference in a natural deduction system. Model theory and Alfred Tarski’s work emphasized the latter. Soundness and completeness theorems for first-order logic show the correspondence of truth and proof, but Kurt Gödel’s second incompleteness theorem shows that a sentence can be true but not proved to be consistent. Tarski 1969 is an excellent introduction to the author’s own theorem of the undefinability of truth. Etchemendy 1990 gives an excellent reconstruction and critique of Tarski’s conception of logical consequence. In constructivist views, proof takes precedence over truth. Realist views, on the contrary, emphasize truth over proof. Michael Dummett’s antirealist program exposed in Dummett 1993 has been influential. Wright 1986 and Tennant 1997 are important works in this tradition. Shapiro 1998 addresses the issue of the compatibility of deflationism and the Gödel phenomena. Halbach and Horsten 2004 and Azouni 2006 are analyses of the relations between truth and proof.

  • Azouni, Jody. Tracking Reason: Proof, Consequence, and Truth. Oxford: Oxford University Press, 2006.

    Save Citation »Export Citation »E-mail Citation »

    Defends a deflationist conception of the relations between proof and truth, where the truth predicates with a special kind of quantifier binding variables in sentential and nominal positions. The resulting theory of truth for a (first-order) language is shown to be able to handle blind truth ascriptions.

    Find this resource:

  • Dummett, Michael. The Logical Basis of Metaphysics. Cambridge, MA: Harvard University Press 1993.

    Save Citation »Export Citation »E-mail Citation »

    Dummett’s program consists in the defense of a theory of meaning in terms of assertion conditions and of an antirealist conception of truth. A theory of meaning and truth must obey constructivist constraints, such as harmony between the introduction and elimination rules of terms and the requirement that any new term introduced in a language must be a conservative extension of the language. These constraints define a molecularist conception of meaning associated with a form of verificationist view of truth, construed in terms of proof.

    Find this resource:

  • Etchemendy, John. The Concept of Logical Consequence. Cambridge, MA: Harvard University Press, 1990.

    Save Citation »Export Citation »E-mail Citation »

    A critique of Alfred Tarski’s conception of logical consequence and a defense of a rethinking of the model theoretic view of consequence in logic.

    Find this resource:

  • Halbach, Volker, and Leon Horsten, eds. Principles of Truth. 2d ed. Frankfurt: Ontos Verlag, 2004.

    Save Citation »Export Citation »E-mail Citation »

    This collection gives an up-to-date account of the issues surrounding the relationships between truth and proof in contemporary philosophy and mathematical logic.

    Find this resource:

  • Shapiro, Stuart. “Proof and Truth: Through Thick and Thin.” Journal of Philosophy 95.10 (1998): 493–521.

    DOI: 10.2307/2564719Save Citation »Export Citation »E-mail Citation »

    Argues that a proof can be given of the consistency of a mathematical theory, whereas in general, mathematical theories cannot prove their own consistency (by Kurt Gödel’s second incompleteness theorem). Thus truth is nonconservative over background mathematical theories and has, contrary to what deflationism claims, an explanatory bite.

    Find this resource:

  • Tarski, Alfred. “Truth and Proof.” Scientific American 220 (1969): 63–77.

    DOI: 10.1038/scientificamerican0669-63Save Citation »Export Citation »E-mail Citation »

    A popular account of truth and its relations to proof and a statement of Tarski’s theorem that truth cannot be defined, by one of the main logicians of the 20th century.

    Find this resource:

  • Tennant, N. The Taming of the True. Oxford: Oxford University Press, 1997.

    Save Citation »Export Citation »E-mail Citation »

    Tennant argues for a form of antirealism about truth based on a version of relevance logic, which has the consequence that all truths are knowable, thus accepting the consequences of Fitch’s knowability argument.

    Find this resource:

  • Wright, Crispin. Realism, Meaning, and Truth. Oxford: Blackwell, 1986.

    Save Citation »Export Citation »E-mail Citation »

    An articulation and defense of Michael Dummett’s antirealist and constructivist program both in logic and in the theory of meaning conceived in terms of assertion conditions and inspired by Ludwig Wittgenstein’s views in the philosophy of mathematics. Second edition published in 1993.

    Find this resource:

Identity

Cartwright 1987 attracted attention to the neglected view of truth as the identity of propositions and facts, which was defended by G. E. Moore and Bertrand Russell in their early philosophical works. But how can one say that thoughts are identical with things unless one falls into a kind of absolute idealism? Baldwin 1991 traces its origin to F. H. Bradley and G. W. F. Hegel. Hornsby 1997 and Dodd 2000 argue that it is actually a form of minimalism about truth. Candlish 2006 introduces theories of truth as identity.

Paradoxes

The primary motivation for many theories of truth, from the ancients and the medievals, was to solve the paradoxes of truth, such as the liar paradox. It was also Alfred Tarski’s objective with his semantic theory. But a number of logicians have given rival treatments in their works, in particular Kripke 1975 and McGee 1990, and have tried to solve the paradoxes on the basis on nonclassical logics (see Priest 2006, Beall 2009, Field 2008, and Patterson 2007). On these views, the question arises of how to interpret Tarski’s equivalence schema.

Facts, Ontology, and Truth making

The most powerful argument against correspondence theories of truth using the notion of fact is a variation on reasoning by Gottlob Frege and Kurt Gödel known as the “slingshot argument,” which purports to show that if a sentence is made true by a fact, it is made true by all the facts or by a single big fact in which the world consists. This argument (see Davidson 1969) has been resisted, and Neale 2001 gives an account. But there are strong arguments to revive an ontology of facts in the style (among others) of Ludwig Wittgenstein’s Tractatus logico-philosophicus (Correia and Mulligan 2007), and a number of philosophers define truth in terms of the relation of truth making that every truth has with an entity that makes it true (Armstrong 2004). Bebee and Dodd 2005 and Lowe and Rami 2009 are collections of the most important essays. Merricks 2007 defends the opposite view that truth does not depend on being, hence that an ontology of truth is impossible.

Recent Debates

Apart from the ongoing discussions on truth, proof, and realism, two sets of issues have been the focus of much recent philosophical attention: the problem of truth relativism (see Relativism and Pluralism), renewed by contextualist views in the philosophy of language, and the issue of the value of truth (see Normativity and the Value of Truth), which has been a central concern of philosophers from Plato to Friedrich Nietzsche to Michel Foucault.

Relativism and Pluralism

Relativism about truth has been present in the philosophical landscape ever since Protagoras. The idea that the same proposition P could be true for X who says P but not for Y who says not P and that both could nevertheless be right has struck most philosophers since Plato as incoherent, including when it is defended along contemporary postmodernist lines (criticized in Boghossian 2005). But a number of contemporary philosophers have revived local forms of relativism about truth on the basis of considerations about context and the idea that there can be “faultless disagreements” (Garcia-Carpintero and Kölbel 2008, MacFarlane 2005, Richard 2008). For a good review of the relativist arguments, see Coliva 2009. Pluralism about truth, as defended in Wright 1992 (cited under Deflationism and Minimalism) and Lynch 2009, is not a form of relativism; it is the view that although truth is distinct depending on the domain of discourse, it has a common core.

Normativity and the Value of Truth

Issues about truth are distinct but not completely independent of issues about the value of truth. Although truth is considered by most philosophers to be a good thing and the ultimate goal of inquiry, there are those, such as Friedrich Nietzsche and Michel Foucault, who attempt to demythologize truth (see Blackburn 2005 for a critique). But these views often confound truth itself with our beliefs about truth. Williams 2002 offers a non-Nietzschean genealogy of truth. It is also held that truth is a norm for belief (see Engel 2000), but this view is resisted by deflationists about truth (see Heal 1987–1988, Horwich 2003).

LAST MODIFIED: 06/29/2011

DOI: 10.1093/OBO/9780195396577-0120

back to top

Article

Up

Down