Additionally, you will have the option to unsubscribe at any point, should you decide to do so. Back to Resources. Four Truths. Objective Truth is what exists and can be proved in this physicality. The sun moves across the sky each day.
Normative Truth is what we, as a group, agree is true. English speakers agreed to use the word day to name that time when the sky is lit by the sun. Subjective Truth is how the individual sees or experiences the world.
But the theory that sentence-tokens are the bearers of truth-values has its own problems. One objection to the nominalist theory is that had there never been any language-users, then there would be no truths.
And the same objection can be leveled against arguing that it is beliefs that are the bearers of truth-values: had there never been any conscious creatures then there would be no beliefs and, thus, no truths or falsehoods, not even the truth that there were no conscious creatures — an unacceptably paradoxical implication. And a second objection — to the theory that sentence-tokens are the bearers of truth-values — is that even though there are language-users, there are sentences that have never been uttered and never will be.
Consider, for example, the distinct number of different ways that a deck of playing cards can be arranged. And there are countless other examples as well. Sentence-tokens, then, cannot be identified as the bearers of truth-values — there simply are too few sentence-tokens. Thus both theories — i that sentence-tokens are the bearers of truth-values, and ii that sentence-types are the bearers of truth-values — encounter difficulties. Might propositions be the bearers of truth-values?
To escape the dilemma of choosing between tokens and types, propositions have been suggested as the primary bearers of truth-values. The following five sentences are in different languages, but they all are typically used to express the same proposition or statement. The truth of the proposition that Saturn is the sixth planet from the Sun depends only on the physics of the solar system, and not in any obvious way on human convention.
By contrast, what these five sentences say does depend partly on human convention. By choosing propositions rather than sentences as the bearers of truth-values, this relativity to human conventions does not apply to truth, a point that many philosophers would consider to be a virtue in a theory of truth.
Propositions are abstract entities; they do not exist in space and time. Terminology aside, the essential point is that propositions are not concrete or material objects. The theory that propositions are the bearers of truth-values also has been criticized. Nominalists object to the abstract character of propositions.
The relationship between sentences and propositions is a serious philosophical problem. Because it is the more favored theory, and for the sake of expediency and consistency, the theory that propositions — and not sentences — are the bearers of truth-values will be adopted in this article.
But it should be pointed out that virtually all the claims made below have counterparts in nominalistic theories which reject propositions. These constraints require that every proposition has exactly one truth-value.
Although the point is controversial, most philosophers add the further constraint that a proposition never changes its truth-value in space or time. Similarly, when someone at noon on January 15, in Vancouver says that the proposition that it is raining is true in Vancouver while false in Sacramento, that person is really talking of two different propositions: i that it rains in Vancouver at noon on January 15, and ii that it rains in Sacramento at noon on January 15, The person is saying proposition i is true and ii is false.
Not all sentences express propositions. But do all declarative sentences express propositions? The following four kinds of declarative sentences have been suggested as not being typically used to express propositions, but all these suggestions are controversial.
In a famous dispute, Russell disagreed with Strawson, arguing that the sentence does express a proposition, and more exactly, a false one. What about declarative sentences that refer to events in the future?
Presumably, today we do not know whether there will be such a battle. Because of this, some philosophers including Aristotle who toyed with the idea have argued that the sentence, at the present moment, does not express anything that is now either true or false. Another, perhaps more powerful, motivation for adopting this view is the belief that if sentences involving future human actions were to express propositions, i.
To defend free will, these philosophers have argued, we must deny truth-values to predictions. This complicating restriction — that sentences about the future do not now express anything true or false — has been attacked by Quine and others.
These critics argue that the restriction upsets the logic we use to reason with such predictions. For example, here is a deductively valid argument involving predictions:. If there will be a run on the bank tomorrow, then the CEO should be awakened. Without assertions in this argument having truth-values, regardless of whether we know those values, we could not assess the argument using the canons of deductive validity and invalidity. We would have to say — contrary to deeply-rooted philosophical intuitions — that it is not really an argument at all.
For another sort of rebuttal to the claim that propositions about the future cannot be true prior to the occurrence of the events described, see Logical Determinism. A liar sentence can be used to generate a paradox when we consider what truth-value to assign it. As a way out of paradox, Kripke suggests that a liar sentence is one of those rare declarative sentences that does not express a proposition. The sentence falls into the truth-value gap.
See the article Liar Paradox. Making the latter choice, some philosophers argue that these declarative sentences do not express propositions. It is the goal of scientific inquiry, historical research, and business audits.
We understand much of what a sentence means by understanding the conditions under which what it expresses is true. Yet the exact nature of truth itself is not wholly revealed by these remarks. Historically, the most popular theory of truth was the Correspondence Theory.
First proposed in a vague form by Plato and by Aristotle in his Metaphysics , this realist theory says truth is what propositions have by corresponding to a way the world is.
The theory says that a proposition is true provided there exists a fact corresponding to it. In other words, for any proposition p,. Perhaps an analysis of the relationship will reveal what all the truths have in common. Consider the proposition that snow is white. Surely the correspondence is not a word by word connecting of a sentence to its reference. It is some sort of exotic relationship between, say, whole propositions and facts.
In presenting his theory of logical atomism early in the twentieth century, Russell tried to show how a true proposition and its corresponding fact share the same structure. And what are facts? The notion of a fact as some sort of ontological entity was first stated explicitly in the second half of the nineteenth century. The Correspondence Theory does permit facts to be mind-dependent entities. McTaggart, and perhaps Kant, held such Correspondence Theories.
The Correspondence theories of Russell , Wittgenstein and Austin all consider facts to be mind-independent. But regardless of their mind-dependence or mind-independence, the theory must provide answers to questions of the following sort. It might be argued that they must be different facts because one expresses the relationship of stabbing but the other expresses the relationship of being stabbed, which is different.
In addition to the specific fact that ball 1 is on the pool table and the specific fact that ball 2 is on the pool table, and so forth, is there the specific fact that there are fewer than 1,, balls on the table?
Is there the general fact that many balls are on the table? Does the existence of general facts require there to be the Forms of Plato or Aristotle? What about the negative proposition that there are no pink elephants on the table? Does it correspond to the same situation in the world that makes there be no green elephants on the table? The same pool table must involve a great many different facts.
These questions illustrate the difficulty in counting facts and distinguishing them. The difficulty is well recognized by advocates of the Correspondence Theory, but critics complain that characterizations of facts too often circle back ultimately to saying facts are whatever true propositions must correspond to in order to be true.
Davidson also has argued that facts really are the true statements themselves; facts are not named by them, as the Correspondence Theory mistakenly supposes. Defenders of the Correspondence Theory have responded to these criticisms in a variety of ways.
Snow is a constituent of the fact that snow is white, but snow is not a constituent of a linguistic entity, so facts and true statements are different kinds of entities. Recent work in possible world semantics has identified facts with sets of possible worlds. The fact that the cat is on the mat contains the possible world in which the cat is on the mat and Adolf Hitler converted to Judaism while Chancellor of Germany.
The motive for this identification is that, if sets of possible worlds are metaphysically legitimate and precisely describable, then so are facts.
To more rigorously describe what is involved in understanding truth and defining it, Alfred Tarski created his Semantic Theory of Truth. The Semantic Theory is the successor to the Correspondence Theory.
Line 1 is about truth. Einstein derived his theories of special and general relativity with a pad of paper, not with an experiment though the experiments that followed have demonstrated that his assertions were in fact true. Historic truth is an event that actually happened. We know it happened because it left behind evidence, witnesses and other proof. Experimental truth may not have the clear conceptual underpinnings of axiomatic truth, but it holds up to scrutiny.
The world is millions of years old. Every experiment consistently demonstrates this. Experimental truth can also give us a road map to the future.
Vaccines do not cause autism. But realism is a more general idea than physicalism. Any theory that provides objective relations of reference and satisfaction, and builds up a theory of truth from them, would give a form of realism. Making the objectivity of reference the key to realism is characteristic of work of Putnam, e. Another important mark of realism expressed in terms of truth is the property of bivalence.
As Dummett has stressed e. Hence, one important mark of realism is that it goes together with the principle of bivalence : every truth-bearer sentence or proposition is true or false. In much of his work, Dummett has made this the characteristic mark of realism, and often identifies realism about some subject-matter with accepting bivalence for discourse about that subject-matter.
At the very least, it captures a great deal of what is more loosely put in the statement of realism above. Both the approaches to realism, through reference and through bivalence, make truth the primary vehicle for an account of realism. A theory of truth which substantiates bivalence, or builds truth from a determinate reference relation, does most of the work of giving a realistic metaphysics. It might even simply be a realistic metaphysics. We have thus turned on its head the relation of truth to metaphysics we saw in our discussion of the neo-classical correspondence theory in section 1.
There, a correspondence theory of truth was built upon a substantial metaphysics. Here, we have seen how articulating a theory that captures the idea of correspondence can be crucial to providing a realist metaphysics.
For another perspective on realism and truth, see Alston Devitt offers an opposing view to the kind we have sketched here, which rejects any characterization of realism in terms of truth or other semantic concepts.
In light of our discussion in section 1. When Moore and Russell held the identity theory of truth, they were most certainly realists. The right kind of metaphysics of propositions can support a realist view, as can a metaphysics of facts.
The modern form of realism we have been discussing here seeks to avoid basing itself on such particular ontological commitments, and so prefers to rely on the kind of correspondence-without-facts approach discussed in section 3.
This is not to say that realism will be devoid of ontological commitments, but the commitments will flow from whichever specific claims about some subject-matter are taken to be true.
For more on realism and truth, see Fumerton and the entry on realism. It should come as no surprise that the relation between truth and metaphysics seen by modern realists can also be exploited by anti-realists. Many modern anti-realists see the theory of truth as the key to formulating and defending their views. With Dummett e. Indeed, many contemporary forms of anti-realism may be formulated as theories of truth, and they do typically deny bivalence. Anti-realism comes in many forms, but let us take as an example a somewhat crude form of verificationism.
Such a theory holds that a claim is correct just insofar as it is in principle verifiable , i. So understood, verificationism is a theory of truth. The claim is not that verification is the most important epistemic notion, but that truth just is verifiability. As with the kind of realism we considered in section 4. Truth is not, to this view, a fully objective matter, independent of us or our thoughts. Instead, truth is constrained by our abilities to verify, and is thus constrained by our epistemic situation.
Truth is to a significant degree an epistemic matter, which is typical of many anti-realist positions. As Dummett says, the verificationist notion of truth does not appear to support bivalence. Any statement that reaches beyond what we can in principle verify or refute verify its negation will be a counter-example to bivalence. Take, for instance, the claim that there is some substance, say uranium, present in some region of the universe too distant to be inspected by us within the expected lifespan of the universe.
Insofar as this really would be in principle unverifiable, we have no reason to maintain it is true or false according to the verificationist theory of truth. Verificationism of this sort is one of a family of anti-realist views. Another example is the view that identifies truth with warranted assertibility.
See also works of McDowell, e. Anti-realism of the Dummettian sort is not a descendant of the coherence theory of truth per se. But in some ways, as Dummett himself has noted, it might be construed as a descendant — perhaps very distant — of idealism. If idealism is the most drastic form of rejection of the independence of mind and world, Dummettian anti-realism is a more modest form, which sees epistemology imprinted in the world, rather than the wholesale embedding of world into mind.
At the same time, the idea of truth as warranted assertibility or verifiability reiterates a theme from the pragmatist views of truth we surveyed in section 1. Anti-realist theories of truth, like the realist ones we discussed in section 4. Convention T, in particular, does not discriminate between realist and anti-realist notions of truth. Likewise, the base clauses of a Tarskian recursive theory are given as disquotation principles, which are neutral between realist and anti-realist understandings of notions like reference.
As we saw with the correspondence theory, giving a full account of the nature of truth will generally require more than the Tarskian apparatus itself.
How an anti-realist is to explain the basic concepts that go into a Tarskian theory is a delicate matter. As Dummett and Wright have investigated in great detail, it appears that the background logic in which the theory is developed will have to be non-classical.
For more on anti-realism and truth, see Shieh and the papers in Greenough and Lynch and the entry on realism. Dummett himself stressed parallels between anti-realism and intuitionism in the philosophy of mathematics.
There Putnam glosses truth as what would be justified under ideal epistemic conditions. With the pragmatists, Putnam sees the ideal conditions as something which can be approximated, echoing the idea of truth as the end of inquiry. Davidson has distanced himself from this interpretation e.
Insofar as these are human attitudes or relate to human actions, Davidson grants there is some affinity between his views and those of some pragmatists especially, he says, Dewey.
Another view that has grown out of the literature on realism and anti-realism, and has become increasingly important in the current literature, is that of pluralism about truth. This view, developed in work of Lynch e. Wright, in particular, suggests that in certain domains of discourse what we say is true in virtue of a correspondence-like relation, while in others it is its true in virtue of a kind of assertibility relation that is closer in spirit to the anti-realist views we have just discussed.
However, whether or not a pluralist view is committed to such claims has been disputed. In particular, Lynch b; develops a version of pluralism which takes truth to be a functional role concept.
The functional role of truth is characterized by a range of principles that articulate such features of truth as its objectivity, its role in inquiry, and related ideas we have encountered in considering various theories of truth. A related point about platitudes governing the concept of truth is made by Wright But according to Lynch, these display the functional role of truth.
Like all functional role concepts, truth must be realized, and according to Lynch it may be realized in different ways in different settings. Such multiple realizability has been one of the hallmarks of functional role concepts discussed in the philosophy of mind.
For instance, Lynch suggests that for ordinary claims about material objects, truth might be realized by a correspondence property which he links to representational views , while for moral claims truth might be manifest by an assertibility property along more anti-realist lines. For more on pluralism about truth, see Pedersen and Lynch and the entry on pluralist theories of truth.
We began in section 1 with the neo-classical theories, which explained the nature of truth within wider metaphysical systems. We then considered some alternatives in sections 2 and 3, some of which had more modest ontological implications. But we still saw in section 4 that substantial theories of truth tend to imply metaphysical theses, or even embody metaphysical positions. One long-standing trend in the discussion of truth is to insist that truth really does not carry metaphysical significance at all.
It does not, as it has no significance on its own. A number of different ideas have been advanced along these lines, under the general heading of deflationism. Deflationist ideas appear quite early on, including a well-known argument against correspondence in Frege — However, many deflationists take their cue from an idea of Ramsey , often called the equivalence thesis :.
Ramsey himself takes truth-bearers to be propositions rather than sentences. This can be taken as the core of a theory of truth, often called the redundancy theory. For instance, they may be acts of confirming or granting what someone else said. Strawson would also object to my making sentences the bearers of truth. In either its speech act or meaning form, the redundancy theory argues there is no property of truth. It is commonly noted that the equivalence thesis itself is not enough to sustain the redundancy theory.
It merely holds that when truth occurs in the outermost position in a sentence, and the full sentence to which truth is predicated is quoted, then truth is eliminable. What happens in other environments is left to be seen. Modern developments of the redundancy theory include Grover et al. The equivalence principle looks familiar: it has something like the form of the Tarski biconditionals discussed in section 2.
However, it is a stronger principle, which identifies the two sides of the biconditional — either their meanings or the speech acts performed with them. The Tarski biconditionals themselves are simply material biconditionals. A number of deflationary theories look to the Tarski biconditionals rather than the full equivalence principle. Their key idea is that even if we do not insist on redundancy, we may still hold the following theses:.
We will refer to views which adopt these as minimalist. Officially, this is the name of the view of Horwich , but we will apply it somewhat more widely. It comes near to saying that truth is not a property at all; to the extent that truth is a property, there is no more to it than the disquotational pattern of the Tarski biconditionals. As Horwich puts it, there is no substantial underlying metaphysics to truth.
And as Soames stresses, certainly nothing that could ground as far-reaching a view as realism or anti-realism. Deflationists typically note that the truth predicate provides us with a convenient device of disquotation. For more on blind ascriptions and their relation to deflationism, see Azzouni, Suggestions like this are found in Leeds, and Quine, Recognizing these uses for a truth predicate, we might simply think of it as introduced into a language by stipulation.
The Tarski biconditionals themselves might be stipulated, as the minimalists envisage. One could also construe the clauses of a recursive Tarskian theory as stipulated.
There are some significant logical differences between these two options. See Halbach and Ketland for discussion. Other deflationists, such as Beall or Field , might prefer to focus here on rules of inference or rules of use, rather than the Tarski biconditionals themselves.
There are also important connections between deflationist ideas about truth and certain ideas about meaning. These are fundamental to the deflationism of Field ; , which will be discussed in section 6.
For an insightful critique of deflationism, see Gupta For more on deflationism, see Azzouni and the entry on the deflationary theory of truth. One of the important themes in the literature on truth is its connection to meaning, or more generally, to language.
This has proved an important application of ideas about truth, and an important issue in the study of truth itself. This section will consider a number of issues relating truth and language. There have been many debates in the literature over what the primary bearers of truth are. Candidates typically include beliefs, propositions, sentences, and utterances. We have already seen in section 1 that the classical debates on truth took this issue very seriously, and what sort of theory of truth was viable was often seen to depend on what the bearers of truth are.
In spite of the number of options under discussion, and the significance that has sometimes been placed on the choice, there is an important similarity between candidate truth-bearers. Consider the role of truth-bearers in the correspondence theory, for instance. We have seen versions of it which take beliefs, propositions, or interpreted sentences to be the primary bearers of truth.
But all of them rely upon the idea that their truth-bearers are meaningful , and are thereby able to say something about what the world is like. No assumptions about just what stands in relations to what objects are required to see truth-bearers as meaningful. It is in virtue of being meaningful that truth-bearers are able to enter into correspondence relations. Truth-bearers are things which meaningfully make claims about what the world is like, and are true or false depending on whether the facts in the world are as described.
Exactly the same point can be made for the anti-realist theories of truth we saw in section 4. Though it is somewhat more delicate, something similar can be said for coherence theories, which usually take beliefs, or whole systems of beliefs, as the primary truth-bearers. Though a coherence theory will hardly talk of beliefs representing the facts, it is crucial to the coherence theory that beliefs are contentful beliefs of agents, and that they can enter into coherence relations.
Noting the complications in interpreting the genuine classical coherence theories, it appears fair to note that this requires truth-bearers to be meaningful, however the background metaphysics presumably idealism understands meaning. Though Tarski works with sentences, the same can be said of his theory. They characterize the world as being some way or another, and this in turn determines whether they are true or false.
But note that just what this fact of the matter consists in is left open by the Tarskian apparatus. We thus find the usual candidate truth-bearers linked in a tight circle: interpreted sentences, the propositions they express, the belief speakers might hold towards them, and the acts of assertion they might perform with them are all connected by providing something meaningful.
This makes them reasonable bearers of truth. For this reason, it seems, contemporary debates on truth have been much less concerned with the issue of truth-bearers than were the classical ones. Some issues remain, of course.
Different metaphysical assumptions may place primary weight on some particular node in the circle, and some metaphysical views still challenge the existence of some of the nodes.
Perhaps more importantly, different views on the nature of meaning itself might cast doubt on the coherence of some of the nodes. Notoriously for instance, Quineans e. Even so, it increasingly appears doubtful that attention to truth per se will bias us towards one particular primary bearer of truth. There is a related, but somewhat different point, which is important to understanding the theories we have canvassed.
The neo-classical theories of truth start with truth-bearers which are already understood to be meaningful, and explain how they get their truth values.
But along the way, they often do something more. Take the neo-classical correspondence theory, for instance. This theory, in effect, starts with a view of how propositions are meaningful.
They are so in virtue of having constituents in the world, which are brought together in the right way. There are many complications about the nature of meaning, but at a minimum, this tells us what the truth conditions associated with a proposition are.
The theory then explains how such truth conditions can lead to the truth value true , by the right fact existing. Many theories of truth are like the neo-classical correspondence theory in being as much theories of how truth-bearers are meaningful as of how their truth values are fixed. Again, abstracting from some complications about meaning, this makes them theories both of truth conditions and truth values. The Tarskian theory of truth can be construed this way too.
This can be seen both in the way the Tarski biconditionals are understood, and how a recursive theory of truth is understood. As we explained Convention T in section 2. Likewise, the base clauses of the recursive definition of truth, those for reference and satisfaction, are taken to state the relevant semantic properties of constituents of an interpreted sentence.
But they also show us the truth conditions of a sentence are determined by these semantic properties.
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