Meaning (philosophy)

Linguistic and non-linguistic

Linguistic meaning concerns the sense of expressions formed according to a language, such as English or Japanese. Languages are typically spoken or written, but there are also sign languages based on gestures, like American Sign language. Languages are complex sign systems to communicate ideas. They use semantic units, such as words, to construct more complex expressions, including sentences and longer texts. This process follows conventions, such as the rules of grammar. They are shared within a linguistic community, governing how expressions are formed and what meanings they have.^[11]

Non-linguistic meaning encompasses the significance conveyed outside of language. Many non-linguistic sign systems are used to communicate meaning, including traffic signals, gestures, facial expressions, maps, and emojis.^[12] Linguistic and non-linguistic meaning do not exclude each other and can overlap. For example, paralanguage comprises non-linguistic elements that shape the meaning of linguistic expressions or convey additional information. Articulation, rhythm, pitch, and loudness are paralinguistic elements in spoken language, while colors and fonts serve as paralinguistic markers in written communication.^[13]

Philosophical inquiry into meaning often centers on linguistic meaning. One reason is the idea that language is the most complex and general sign system, serving as a paradigm case that can also describe meanings expressed in other sign systems.^[14]

Descriptive and emotive

Descriptive meaning, also called cognitive^[a] or propositional meaning, signifies objects or conveys facts about the world. It takes the form of propositions, which state information that can be true or false.^[23] Descriptive meaning contrasts with emotive meaning, also termed expressive meaning, which reflects the speaker's emotions or evokes emotions in the audience. For example, yelling "Ouch!" after stepping on a sharp piece of glass is an expression of emotive meaning, whereas the statement "I just felt a sudden sharp pain" has descriptive meaning.^[24] A single expression can have both descriptive and emotive meaning. Similarly, two words may be synonyms regarding their descriptive meaning by referring to the same entities but differ in their emotive meaning. In this case, they express different evaluative attitudes, like the contrast between the words dad and father.^[25]

Various philosophical discussions address whether sentences within a given domain have primarily descriptive or emotive meaning. For instance, ethical cognitivists argue that moral language, like the sentence "murder is wrong", has descriptive meaning and can be true or false. Ethical emotivists, by contrast, hold that such sentences have primarily emotive meaning by expressing attitudes of approval or disapproval. This outlook is a form of anti-realism that challenges the claim that ethical evaluations represent objective reality.^[26] Similar debates are found in the field of aesthetics regarding the value of artworks.^[27]

In addition to its contrast with emotive meaning, descriptive meaning is also distinguished from normative or prescriptive meaning: descriptive meaning expresses what is the case, whereas normative meaning conveys what should be the case.^[28]

Speaker, conventional, and figurative

The contrast between speaker meaning and conventional meaning depends on the source or location of the meaning. Speaker meaning is what a person intends to communicate, reflecting the ideas they associate with an expression. Conventional meaning arises from shared social norms that govern language use in a community, such as the dictionary definition of a word. Speaker meaning and conventional meaning align when a person follows established conventions to express what they intend to say. However, they can come apart when a speaker employs a word idiosyncratically or mistakenly in a way that diverges from public linguistic norms, which can lead to miscommunication.^[29][b]

An overlapping distinction is between literal and figurative meaning. The literal meaning of an expression is its standard sense based on conventional use. Figurative meaning involves the creative use of expressions in unconventional ways, often in situations where it is clear from the context that the standard sense is not intended.^[31] This occurs in verbal irony when a person says the opposite of what they mean, such as remarking "Great job!" after a disastrous failure.^[32] Philosophical discussions explore whether figurative meaning can be explained in terms of literal meaning together with contextual factors, and whether figurative uses are a primary mechanism by which language changes and new meanings and concepts emerge.^[33]

Others

The distinction between natural and non-natural meaning depends on the relation between a sign and what it stands for. Natural meaning rests on non-conventional relations and is not affected by what people intend or desire. For example, smoke acts as a sign of fire because fire causes smoke, independent of community-specific norms and practices. Similarly, the footprint of a dog points to a dog because of the physical connection between the sign and the animal. Non-natural meaning, by contrast, is grounded in established norms and conventions. In this case, there is no inherent link between the sign and its referent, making the connection arbitrary in a certain sense. For instance, the meaning of the word cherry is non-natural, and studying its sounds does not reveal an intrinsic link to the fruit. Sign systems used in human communication are often non-natural, such as language and the color-coding of traffic lights.^[34][c]

The distinction between narrow and wide (or broad) meaning concerns the influence of external circumstances. Narrow meaning is fully determined by the internal states of a person, such as brain states, and reflects the conceptual role that meaning contents play in thought. Accordingly, two persons with exactly the same internal states share the same narrow meanings in their thoughts. Wide meaning, by contrast, also considers external factors that may influence to which object a meaning content refers. In this respect, two persons with identical internal states in different circumstances can have different wide meanings because their thoughts relate differently to their environments. The distinction between narrow and wide meaning plays a central role in philosophical discussions about the nature of mind, particularly concerning the question of whether mental states depend only on brain states or also on the environment.^[36]

Focal meaning describes a pattern in which several applications of a term to diverse items are all intelligible through their shared reference to a primary case. For example, the word healthy can be applied to persons, food items, places, and complexion, unified by their common relation to health.^[37]

The meaning of life concerns a form of non-linguistic meaning discussed in metaphysics and value theory. It addresses the significance of human life or existence as a whole, asking whether there is a higher purpose or value to the world.^[38] Naturalism is one response to this question, arguing that meaning is inherent in the physical world, either as objective values that apply universally or as subjective values shaped by individual preferences.^[39] Supernaturalism, another approach, posits a source of meaning beyond the physical world, such as the will of a divine creator imbuing existence with significance.^[40] Existential nihilism rejects both views, holding instead that there is no higher purpose and that life is ultimately meaningless.^[41]

Sense, reference, and truth

Various concepts are used in the philosophical analysis of meaning. Sense and reference are commonly discussed as two central components.^[d] The reference of an expression is the object or class of entities to which it applies. The sense of an expression is the way it presents or refers to those entities. For example, the terms morning star and evening star have the same reference since both signify the planet Venus. However, they have different senses because they present this object in different ways.^[43] Some expressions lack reference since they do not denote any existing entity, including empty names like Pegasus.^[44]

Meaning is closely associated with speech acts, which are communicative actions.^[45] Speech acts are often analyzed in terms of semantic content and force. The semantic content of a speech act is the information it carries or the subject matter it concerns. Its force is how the speaker uses this content, as in the contrast between asserting, questioning, promising, or demanding a specific outcome. According to the content–force analysis, the utterances "All dogs can swim." and "All cats can swim." have different contents but the same force: both make assertions, but they assert different things. By contrast, "All dogs can swim." and "Can all dogs swim?" have the same content but different forces: they share the subject matter of the swimming ability of dogs, but the first states this as a fact while the second poses it as a question.^[46]

Truth and falsity are features of the meaning of declarative sentences or assertive speech acts: true sentences align with reality, describing the world as it is, whereas false ones fail to do so.^[47] Various philosophical theories of the nature of truth have been proposed. They include the views that truth is correspondence to facts, coherence among beliefs, or practical usefulness and the ability to withstand unlimited inquiry.^[48] A truth condition is a situation in which a sentence would be true.^[49] One view analyzes the meaning of declarative sentences in terms of truth conditions, holding that understanding a sentence is about knowing what the world must be like for the sentence to be true.^[50]

Vagueness, ambiguity, and context-dependence

Vagueness and ambiguity concern meanings that lack clear or unified boundaries. An expression is vague if there are borderline cases in which it is indeterminate whether it applies. For example, the term tall is vague because there is no clear line separating entities that are tall from those that are not. Vagueness plays a key role in the Sorites paradox, which centers on borderline cases and gradual change, such as the difficulty of determining when a heap of sand stops being a heap as individual grains are successively removed. Vagueness differs from ambiguity, a quality of expressions with several distinct meanings. For example, lexical ambiguity concerns word meanings, such as the word bat, which denotes a winged mammal and a club-like piece of sports equipment.^[51] Other forms of ambiguity include structural ambiguity, in which the grammatical structure of a sentence can be interpreted in several ways, and referential ambiguity, in which it is unclear which entity an expression, such as the pronoun he, denotes.^[52]

Context-dependence, or context-sensitivity, involves meaning contents that are underspecified without a context. They require information from the surrounding situation or discourse to acquire a determinate meaning. For example, the expressions here, last week, and she need contextual cues to fix which location, time, or person is meant. Contextualism is the view that the meaning of most or all expressions or utterances is context-dependent.^[53]

Context-dependence is closely related to implicature, which encompasses aspects of the meaning of an utterance that are not overtly stated but arise from shared background assumptions and conversational norms. Such norms include the idea that people try to promote the goal of a conversation by saying things that are true, informative, and relevant to the topic. For example, responding "I have to study." to the question "Can you go to the movies?" has the implicature that the speaker is unable to go without stating this overtly, assuming implicitly that the response is relevant and answers the question indirectly.^[54]

Other concepts

The principle of compositionality states that the meaning of a complex expression is determined by the meanings of its parts and the way they are combined. For example, the meaning of the sentence "Laika was a dog" depends on the meanings of the words Laika, was, a, and dog, as well as the order in which they appear. Compositionality is often used to explain productivity—the idea that competent speakers can form and understand an almost infinite number of sentences after learning a finite number of words and syntactic rules. Philosophers debate to what extent compositionality fully determines meaning or merely influences it. For example, idiomatic expressions like "kick the bucket" challenge the principle of compositionality since it is not always obvious that their meaning is determined by their parts.^[55]

Normativity is a quality of rules, judgments, or concepts that prescribe how things should be.^[56] Meaning is often described as a normative concept because it implies standards of correctness: a meaningful expression is correctly applied to some situations but not to others. For example, the word green is correctly applied to green objects but not to red ones. Philosophers discuss the precise relation between meaning and normativity, including whether the concept of meaning can be reduced to norms or conditions of correct application.^[57]

Meaning is typically attributed to signs, which are entities that stand for something else.^[58] A sign vehicle, one proposed component of a sign, is its physical form, such as sound waves, ink marks, or gestures. The referent is the represented entity, which may be an external object or an idea.^[59] The sign relation is the connection between a sign vehicle and its referent, such as the contrast between conventional and non-conventional connections.^[60] A sign system is a framework of relations and rules governing how signs are formed, combined, and interpreted, such as the Spanish language.^[61] Understanding a sign usually requires some form of interpretation to reveal its meaning.^[62]

Translation is the process of converting an expression from one sign system to another with the goal of preserving its meaning. It is controversial to what extent this goal is achievable. For example, the thesis of the indeterminacy of translation states that it is typically impossible to decide which among multiple possible translations with slightly different meanings is correct.^[63][e]

Meaning postulates are principles that describe general logical relations between concepts, such as the idea that the concept bachelor implies the concept unmarried. They have been used to explain the truth of analytic statements—statements whose truth depends only on the meanings of the words they use, independent of empirical reality, such as the statement "all bachelors are unmarried". According to one view, analytic statements are true because the relations among their meaning contents are fixed by meaning postulates.^[65]

Based on reference and truth conditions

Referential theories assert that the meaning of expressions is given by what they stand for. This view treats expressions similar to labels that denote real entities in the world, with different types of expressions associated with different kinds of referents. According to a common approach, a name, such as Mahatma Gandhi, means the individual person it denotes; a general term, such as dog, means the set of entities to which it applies; and a full sentence, such as "The cat sat on the mat", means the situation it describes or the truth value it has.^[69] A similar outlook is presented in the picture theory of meaning, an early view of Ludwig Wittgenstein. It holds that expressions act like pictures or models of reality: words correspond to basic objects, grammar mirrors relations between objects, and sentences depict possible states of affairs.^[70]

A key appeal of referential theories is their closeness to common sense: the meaning of everyday words is often explained by pointing to the entities they denote. They face difficulties in explaining expressions that do not refer to actual objects. Problematic cases include names of nonexistent entities, such as Pegasus, and expressions that do not appear to denote entities, such as very, of, and hey. Another challenge comes from coreferring terms that are not synonyms, that is, expressions that denote the same entity but differ in meaning, such as "the square root of 4" and "the cube root of 8".^[71]

Like referential theories, truth-conditional theories emphasize the relation between meaning and reality. They propose that understanding the meaning of a sentence requires understanding the conditions under which it would be true or what the world would be like in this case.^[72] An influential version, proposed by Donald Davidson, analyzes meaning in a specific language by constructing a theory that systematically explains how to relate a statement to its truth conditions. This happens in the form of so-called T-sentences, which have the form: '"${\displaystyle S}$" is true in ${\displaystyle L}$ if and only if ${\displaystyle p}$', where ${\displaystyle S}$ is the analyzed sentence, ${\displaystyle L}$ is the language of the sentence, and ${\displaystyle p}$ encompasses the truth conditions. This approach studies general patterns of T-sentences, for example, by relying on compositionality to explain how the truth conditions of complex statements are determined by the truth conditions of their constituents.^[73] Another approach explains truth conditions in terms of possible worlds, which are alternative ways of how reality could have been. According to this view, the meaning of a sentence is the set of possible worlds in which it is true.^[74]

A central motivation for truth-conditional theories is that they explain the relation between language and reality while providing a precise way to characterize meaning. One objection is that truth-conditional theories are limited to assertions that describe the world without explaining the meaning of other sentence types, such as questions and commands. Another challenge arises from statements with identical truth-conditions but different meanings. For example, the statements "2 + 2 = 4" and "either today is Monday or it is not" have different meanings, but truth-conditional theories suggest that they have the same meaning since both are always true, regardless of what the world is like.^[75]

Based on mind and abstract objects

Mind-based theories characterize meaning in terms of mental processes and ideas, avoiding the focus on the relation between language and world found in referential and truth-conditional theories. The ideational theory, proposed by John Locke, holds that linguistic expressions stand for ideas in the minds of language users. On this account, the word apple means the idea that language users have of apples. This view holds that language is a medium through which people express and share their ideas with others: there are conventional relations between ideas and signs, and once language users associate an idea with a corresponding sign, they can produce the sign and thereby evoke the idea in the minds of other language users who perceive it. Despite its intuitive appeal, the ideational theory faces various objections. For example, the meaning of a word is typically considered a public and social phenomenon that exists for the entire language community, whereas ideas are subjective, and different people may associate different ideas with the same word.^[77]

A related mind-based approach, proposed by Jerry Fodor, holds that meaning in natural language depends on mental representations in thought. It maintains that thought itself has a linguistic structure, with concepts as basic building blocks that can be combined following grammar-like rules. According to this view, natural-language expressions are meaningful because they are paired with mental representations, as in the link between the word house and the mental representation house.^[78]

A different psychological approach, developed by Paul Grice, defines meaning in terms of intentions rather than ideas or concepts. Focusing on speaker meaning instead of conventional meaning, this view argues that people usually aim to provoke some kind of reaction in their audience, such as causing them to form a certain belief. It holds that understanding the meaning of a statement involves recognizing the underlying communicative intention. One strength of this view is that it can explain the meaning of nonliteral expressions, such as irony and sarcasm, by considering how the speaker intended them.^[79] Challenges to the intentionalist theory of meaning come from cases in which people produce meaningful expressions without intending to communicate with others and cases in which the speaker's communicative intention does not align with what the audience reasonably interprets the speaker to mean.^[80]

Proposition theory argues that meanings are not subjective mental ideas but abstract objects that exist independently of mind and language users. According to this view, declarative sentences express propositions, which are conceived as abstract objects that act as the primary locus of meaning. Different sentences can express the same proposition, such as the English sentence "Snow is white" and the German sentence "Schnee ist weiß". Similarly, mental states, such as beliefs, can be about propositions. Proposition theory is often combined with the view that propositions have an internal structure, meaning that they are complex entities made up of several parts. This approach holds that propositions consist of units such as concepts, objects, properties, or relations. Unlike those units, a proposition is a complete thought that can be true or false. One difficulty for proposition theory is its reliance on abstract objects: it is controversial whether such objects exist and, if so, how people could grasp them when they understand the meaning of something.^[81]

Based on use

	a	b	c	d	e	f	g	h
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	a	b	c	d	e	f	g	h

Ludwig Wittgenstein suggested that the meaning of an expression depends on rules governing its use, similar to how the role of chess pieces depends on the rules of chess.^[82]

Use-based theories reject the idea that meaning consists of special objects, like ideas or propositions. Instead, they hold that the meaning of an expression is determined by how it is used or the function it plays in human social behavior. An influential use theory, inspired by Wittgenstein's later works, focuses on publicly observable linguistic behavior and the norms that govern it. According to this view, language resembles a game, and understanding linguistic expressions requires knowing the rules that govern this game. In this regard, using words is similar to moving pieces in a chess game, where understanding the role of a piece, such as a rook, involves familiarity with the rules governing how it can move and interact with other pieces.^[83] Wittgenstein argued that there are many language games, each with its own rules, and that the same expression can occur in different games with different use-dependent meanings. For example, uttering "Water!" may function as a request, a warning, or an answer, depending on the context.^[84] While this form of use-theory can explain the meanings of expressions in simple language games, it faces challenges in applying these principles to more complex cases, such as understanding long and novel sentences one has never heard before.^[85]

Inferentialism, also called conceptual role semantics, is a form of use theory that focuses on the practice of drawing inferences. Developed by Wilfrid Sellars and Robert Brandom, it holds that the meaning of an expression depends on the role it plays in inferences, such as the reasons that can support it and the conclusions that can be drawn from it. For example, the meaning of the word brother is associated with various inferential patterns: being a male sibling entails being a brother, and being a brother entails having parents. Inferentialists take these and comparable inferences to constitute a word's meaning. Unlike some other forms of use theory, inferentialism can also account for the meanings of complex expressions by analyzing their inferential patterns. One objection targets its exclusive focus on inferential practices, arguing that it struggles to explain how expressions can refer to non-linguistic phenomena.^[86]

Other theories

Holism and atomism are views about how meaning is determined by relations among expressions. According to holism, the meanings of individual expressions depend on other expressions: they are meaningful only against the background of a broader system of language or a network of beliefs. This view is rejected by atomism, which holds that the meanings of individual expressions are independent: in principle, they can be understood in isolation without reference to a larger linguistic or conceptual system. Molecularism, an intermediate view, holds that meanings depend on a small semantic field of related expressions but not on the entire system. According to this view, the meaning of the verb to kill depends in part on the meanings of the verbs to cause and to die.^[87]

Verificationism is the view that the meaning of a statement is the procedure required to verify it or the set of experiences that would show it to be true.^[f] A key motivation for this view is the idea that the meaning of true sentences should make a difference to how people experience the world. Accordingly, verificationists hold that a statement is meaningless if it makes no difference because no possible experience could verify it.^[g] This idea has been used by verificationists to dismiss certain areas of philosophy, such as traditional metaphysics, by claiming that their statements are neither true nor false but meaningless. One central objection to verificationism holds that this view is too wide-reaching by dismissing many statements that are typically considered meaningful. For example, the statement "The universe began five minutes ago, including all memories and records" seems meaningful although it is unclear which experiences could verify it. Another criticism from the perspective of holism argues that individual statements do not have verification conditions since their verification depends on assumptions about other statements.^[90]

Behaviorist theories analyze meaning in terms of stimuli and responses, focusing on the situations that trigger an expression and the responses it elicits in an audience. For example, the meaning of yelling "Fire!" is associated with situations in which an individual detects a dangerous fire and with responses such as fleeing or extinguishing it. Accordingly, behaviorist theories of meaning hold that to learn the meaning of an expression, one needs to acquire the relevant stimulus-response pairs. Critics argue that the same expression can prompt different responses in different people without having different meanings for them and that behaviorism struggles to explain compositionality or how the meaning of a complex expression depends on its parts.^[91]

Teleosemantics explains meaning, representation, and related phenomena in terms of their biological function: the purposes or evolutionary roles they serve. A key idea of this approach is that meaning is not limited to humans but is a more basic biological phenomenon found also in other species. For example, vervet monkeys have different warning calls for leopards, eagles, and snakes. According to teleosemantics, these calls have different meanings or representational contents because they are associated with different behavioral responses and functions.^[92]

Some theories of meaning target specific types of expressions rather than linguistic meaning in general. For example, theories of names examine the meaning of proper names, such as Socrates and Paris. Descriptivist and direct-reference theories debate whether the meaning of a name is an exhaustive description of the named entity,^[h] or whether names establish a direct connection without descriptive content.^[94] Other expressions whose meaning is discussed in philosophy of language include indexicals, such as I; definite descriptions, such as "the author of Waverley"; and quantifiers, such as everyone.^[95]

Logic and language

The logical positivists argued that the meaning of a statement arose from how it is verified.

Gottlob Frege

In his paper "Über Sinn und Bedeutung" (now usually translated as "On Sense and Reference"), Gottlob Frege argued that proper names present at least two problems in explaining meaning.

1. Suppose the meaning of a name is the thing it refers to. Sam, then, means a person in the world who is named Sam. But if the object referred to by the name did not exist—i.e., Pegasus—then, according to that theory, it would be meaningless.
2. Suppose two different names refer to the same object. Hesperus and Phosphorus were the names given to what were considered distinct celestial bodies. It was later shown that they were the same thing (the planet Venus). If the words meant the same thing, then substituting one for the other in a sentence would not result in a sentence that differs in meaning from the original. But in that case, "Hesperus is Phosphorus" would mean the same thing as "Hesperus is Hesperus". This is clearly absurd, since we learn something new and unobvious by the former statement, but not by the latter.

Frege can be interpreted as arguing that it was therefore a mistake to think that the meaning of a name is the thing it refers to. Instead, the meaning must be something else—the "sense" of the word. Two names for the same person, then, can have different senses (or meanings): one referent might be picked out by more than one sense. This sort of theory is called a mediated reference theory. Frege argued that, ultimately, the same bifurcation of meaning must apply to most or all linguistic categories, such as to quantificational expressions like "All boats float".

Bertrand Russell

Logical analysis was further advanced by Bertrand Russell and Alfred North Whitehead in their groundbreaking Principia Mathematica, which attempted to produce a formal language with which the truth of all mathematical statements could be demonstrated from first principles.

Russell differed from Frege greatly on many points, however. He rejected Frege's sense-reference distinction. He also disagreed that language was of fundamental significance to philosophy, and saw the project of developing formal logic as a way of eliminating all of the confusions caused by ordinary language, and hence at creating a perfectly transparent medium in which to conduct traditional philosophical argument. He hoped, ultimately, to extend the proofs of the Principia to all possible true statements, a scheme he called logical atomism. For a while it appeared that his pupil Wittgenstein had succeeded in this plan with his Tractatus Logico-Philosophicus.

Russell's work, and that of his colleague G. E. Moore, developed in response to what they perceived as the nonsense dominating British philosophy departments at the turn of the 20th century, which was a kind of British Idealism most of which was derived (albeit very distantly) from the work of Hegel. In response Moore developed an approach ("Common Sense Philosophy"^[96]) which sought to examine philosophical difficulties by a close analysis of the language used in order to determine its meaning. In this way Moore sought to expunge philosophical absurdities such as "time is unreal". Moore's work would have significant, if oblique, influence (largely mediated by Wittgenstein) on Ordinary language philosophy.

Other truth theories of meaning

The Vienna Circle, a famous group of logical positivists from the early 20th century (closely allied with Russell and Frege), adopted the verificationist theory of meaning, a type of truth theory of meaning.^[97] The verificationist theory of meaning (in at least one of its forms) states that to say that an expression is meaningful is to say that there are some conditions of experience that could exist to show that the expression is true. As noted, Frege and Russell were two proponents of this way of thinking.

A semantic theory of truth was produced by Alfred Tarski for formal semantics. According to Tarski's account, meaning consists of a recursive set of rules that end up yielding an infinite set of sentences, "'p' is true if and only if p", covering the whole language. His innovation produced the notion of propositional functions discussed on the section on universals (which he called "sentential functions"), and a model-theoretic approach to semantics (as opposed to a proof-theoretic one). Finally, some links were forged to the correspondence theory of truth (Tarski, 1944).

Perhaps the most influential current approach in the contemporary theory of meaning is that sketched by Donald Davidson in his introduction to the collection of essays Truth and Meaning in 1967. There he argued for the following two theses:

• Any learnable language must be statable in a finite form, even if it is capable of a theoretically infinite number of expressions—as we may assume that natural human languages are, at least in principle. If it could not be stated in a finite way then it could not be learned through a finite, empirical method such as the way humans learn their languages. It follows that it must be possible to give a theoretical semantics for any natural language which could give the meanings of an infinite number of sentences on the basis of a finite system of axioms.
• Giving the meaning of a sentence, he further argued, was equivalent to stating its truth conditions. He proposed that it must be possible to account for language as a set of distinct grammatical features together with a lexicon, and for each of them explain its workings in such a way as to generate trivial (obviously correct) statements of the truth conditions of all the (infinitely many) sentences built up from these.

The result is a theory of meaning that rather resembles, by no accident, Tarski's account.

Davidson's account, though brief, constitutes the first systematic presentation of truth-conditional semantics. He proposed simply translating natural languages into first-order predicate calculus in order to reduce meaning to a function of truth.

Saul Kripke

Saul Kripke examined the relation between sense and reference in dealing with possible and actual situations. He showed that one consequence of his interpretation of certain systems of modal logic was that the reference of a proper name is necessarily linked to its referent, but that the sense is not. So for instance "Hesperus" necessarily refers to Hesperus, even in those imaginary cases and worlds in which perhaps Hesperus is not the evening star. That is, Hesperus is necessarily Hesperus, but only contingently the morning star.

This results in the curious situation that part of the meaning of a name — that it refers to some particular thing — is a necessary fact about that name, but another part — that it is used in some particular way or situation — is not.

Kripke also drew the distinction between speaker's meaning and semantic meaning, elaborating on the work of ordinary language philosophers Paul Grice and Keith Donnellan. The speaker's meaning is what the speaker intends to refer to by saying something; the semantic meaning is what the words uttered by the speaker mean according to the language.

In some cases, people do not say what they mean; in other cases, they say something that is in error. In both these cases, the speaker's meaning and the semantic meaning seem to be different. Sometimes words do not actually express what the speaker wants them to express; so words will mean one thing, and what people intend to convey by them might mean another. The meaning of the expression, in such cases, is ambiguous.

Critiques of truth theories of meaning

W. V. O. Quine attacked both verificationism and the very notion of meaning in his famous essay, "Two Dogmas of Empiricism". In it, he suggested that meaning was nothing more than a vague and dispensable notion. Instead, he asserted, what was more interesting to study was the synonymy between signs. He also pointed out that verificationism was tied to the distinction between analytic and synthetic statements, and asserted that such a divide was defended ambiguously. He also suggested that the unit of analysis for any potential investigation into the world (and, perhaps, meaning) would be the entire body of statements taken as a collective, not just individual statements on their own.

Other criticisms can be raised on the basis of the limitations that truth-conditional theorists themselves admit to. Tarski, for instance, recognized that truth-conditional theories of meaning only make sense of statements, but fail to explain the meanings of the lexical parts that make up statements. Rather, the meaning of the parts of statements is presupposed by an understanding of the truth-conditions of a whole statement, and explained in terms of what he called "satisfaction conditions".

Still another objection (noted by Frege and others) was that some kinds of statements do not seem to have any truth-conditions at all. For instance, "Hello!" has no truth-conditions, because it does not even attempt to tell the listener anything about the state of affairs in the world. In other words, different propositions have different grammatical moods.

Deflationist accounts of truth, sometimes called 'irrealist' accounts, are the staunchest source of criticism of truth-conditional theories of meaning. According to them, "truth" is a word with no serious meaning or function in discourse. For instance, for the deflationist, the sentences "It's true that Tiny Tim is trouble" and "Tiny Tim is trouble" are equivalent. In consequence, for the deflationist, any appeal to truth as an account of meaning has little explanatory power.

The sort of truth theories presented here can also be attacked for their formalism both in practice and principle. The principle of formalism is challenged by the informalists, who suggest that language is largely a construction of the speaker, and so, not compatible with formalization. The practice of formalism is challenged by those who observe that formal languages (such as present-day quantificational logic) fail to capture the expressive power of natural languages (as is arguably demonstrated in the awkward character of the quantificational explanation of definite description statements, as laid out by Bertrand Russell).

Finally, over the past century, forms of logic have been developed that are not dependent exclusively on the notions of truth and falsity. Some of these types of logic have been called modal logics. They explain how certain logical connectives such as "if-then" work in terms of necessity and possibility. Indeed, modal logic was the basis of one of the most popular and rigorous formulations in modern semantics called the Montague grammar. The successes of such systems naturally give rise to the argument that these systems have captured the natural meaning of connectives like if-then far better than an ordinary, truth-functional logic ever could.

Ludwig Wittgenstein

The philosopher Ludwig Wittgenstein was originally an ideal language philosopher, following the influence of Russell and Frege. In his Tractatus Logico-Philosophicus he had supported the idea of an ideal language built up from atomic statements using logical connectives (see picture theory of meaning and logical atomism). However, as he matured, he came to appreciate more and more the phenomenon of natural language. Philosophical Investigations, published after his death, signalled a sharp departure from his earlier work with its focus upon ordinary language use (see use theory of meaning and ordinary language philosophy). His approach is often summarised by the aphorism "the meaning of a word is its use in a language". However, following in Frege's footsteps, in the Tractatus, Wittgenstein declares: "... Only in the context of a proposition has a name meaning."^[98]

His work would come to inspire future generations and spur forward a whole new discipline, which explained meaning in a new way. Meaning in a natural language was seen as primarily a question of how the speaker uses words within the language to express intention.

This close examination of natural language proved to be a powerful philosophical technique. Practitioners who were influenced by Wittgenstein's approach have included an entire tradition of thinkers, featuring P. F. Strawson, Paul Grice, R. M. Hare, R. S. Peters, and Jürgen Habermas.

J. L. Austin

At around the same time Ludwig Wittgenstein was re-thinking his approach to language, reflections on the complexity of language led to a more expansive approach to meaning. Following the lead of George Edward Moore, J. L. Austin examined the use of words in great detail. He argued against fixating on the meaning of words. He showed that dictionary definitions are of limited philosophical use, since there is no simple "appendage" to a word that can be called its meaning. Instead, he showed how to focus on the way in which words are used in order to do things. He analysed the structure of utterances into three distinct parts: locutions, illocutions and perlocutions. His pupil John Searle developed the idea under the label "speech acts". Their work greatly influenced pragmatics.

Peter Strawson

Past philosophers had understood reference to be tied to words themselves. However, Peter Strawson disagreed in his seminal essay, "On Referring", where he argued that there is nothing true about statements on their own; rather, only the uses of statements could be considered to be true or false.

Indeed, one of the hallmarks of the ordinary use perspective is its insistence upon the distinctions between meaning and use. "Meanings", for ordinary language philosophers, are the instructions for usage of words — the common and conventional definitions of words. Usage, on the other hand, is the actual meanings that individual speakers have — the things that an individual speaker in a particular context wants to refer to. The word "dog" is an example of a meaning, but pointing at a nearby dog and shouting "This dog smells foul!" is an example of usage. From this distinction between usage and meaning arose the divide between the fields of pragmatics and semantics.

Yet another distinction is of some utility in discussing language: "mentioning". Mention is when an expression refers to itself as a linguistic item, usually surrounded by quotation marks. For instance, in the expression "'Opopanax' is hard to spell", what is referred to is the word itself ("opopanax") and not what it means (an obscure gum resin). Frege had referred to instances of mentioning as "opaque contexts".

In his essay, "Reference and Definite Descriptions", Keith Donnellan sought to improve upon Strawson's distinction. He pointed out that there are two uses of definite descriptions: attributive and referential. Attributive uses provide a description of whoever is being referred to, while referential uses point out the actual referent. Attributive uses are like mediated references, while referential uses are more directly referential.

Paul Grice

The philosopher Paul Grice, working within the ordinary language tradition, understood "meaning" — in his 1957 article — to have two kinds: natural and non-natural. Natural meaning had to do with cause and effect, for example with the expression "these spots mean measles". Non-natural meaning, on the other hand, had to do with the intentions of the speaker in communicating something to the listener.

In his essay, Logic and Conversation, Grice went on to explain and defend an explanation of how conversations work. His guiding maxim was called the cooperative principle, which claimed that the speaker and the listener will have mutual expectations of the kind of information that will be shared. The principle is broken down into four maxims: Quality (which demands truthfulness and honesty), Quantity (demand for just enough information as is required), Relation (relevance of things brought up), and Manner (lucidity). This principle, if and when followed, lets the speaker and listener figure out the meaning of certain implications by way of inference.

The works of Grice led to an avalanche of research and interest in the field, both supportive and critical. One spinoff was called Relevance theory, developed by Dan Sperber and Deirdre Wilson during the mid-1980s, whose goal was to make the notion of relevance more clear. Similarly, in his work, "Universal pragmatics", Jürgen Habermas began a program that sought to improve upon the work of the ordinary language tradition. In it, he laid out the goal of a valid conversation as a pursuit of mutual understanding.

Noam Chomsky

Although he has focused on the structure and functioning of human syntax, in many works^{[99][100][101][102]} Noam Chomsky has discussed many philosophical problems too, including the problem of meaning and reference in human language. Chomsky has formulated a strong criticism against both the externalist notion of reference (reference consists in a direct or causal relation among words and objects) and the internalist one (reference is a mind-mediated relation holding among words and reality). According to Chomsky, both these notions (and many others widely used in philosophy, such as that of truth) are basically inadequate for the naturalistic (= scientific) inquiry on human mind: they are common sense notions, not scientific notions, which cannot, as such, enter in the scientific discussion. Chomsky argues that the notion of reference can be used only when we deal with scientific languages, whose symbols refers to specific things or entities; but when we consider human language expressions, we immediately understand that their reference is vague, in the sense that they can be used to denote many things. For example, the word “book” can be used to denote an abstract object (e.g., “he is reading the book”) or a concrete one (e.g., “the book is on the chair”); the name “London” can denote at the same time a set of buildings, the air of a place and the character of a population (think to the sentence “London is so gray, polluted and sad”). These and other cases induce Chomsky to argue that the only plausible (although not scientific) notion of reference is that of act of reference, a complex phenomenon of language use (performance) which includes many factors (linguistic and not: i.e. beliefs, desires, assumptions about the world, premises, etc.). As Chomsky himself has pointed out,^[103] this conception of meaning is very close to that adopted by John Austin, Peter Strawson and the late Wittgenstein.^[104]

Inferential role semantics

Michael Dummett argued against the kind of truth-conditional semantics presented by Davidson. Instead, he argued that basing semantics on assertion conditions avoids a number of difficulties with truth-conditional semantics, such as the transcendental nature of certain kinds of truth condition. He leverages work done in proof-theoretic semantics to provide a kind of inferential role semantics, where:

• The meaning of sentences and grammatical constructs is given by their assertion conditions; and
• Such a semantics is only guaranteed to be coherent if the inferences associated with the parts of language are in logical harmony.

A semantics based upon assertion conditions is called a verificationist semantics: cf. the verificationism of the Vienna Circle.

This work is closely related, though not identical, to one-factor theories of conceptual role semantics.

Critiques of use theories of meaning

Sometimes between the 1950-1990s, cognitive scientist Jerry Fodor said that use theories of meaning (of the Wittgensteinian kind) seem to assume that language is solely a public phenomenon, that there is no such thing as a "private language". Fodor thinks it is necessary to create or describe the language of thought, which would seemingly require the existence of a "private language".

In the 1960s, David Kellogg Lewis described meaning as use, a feature of a social convention and conventions as regularities of a specific sort. Lewis' work was an application of game theory in philosophical topics.^[105] Conventions, he argued, are a species of coordination equilibria.