Kareem Khalifa Department of Philosophy Middlebury College.

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Presentation transcript:

Kareem Khalifa Department of Philosophy Middlebury College

Overview I.Preliminaries II.Rejected Theories of Meaning III.Truth-Conditional Semantics (TCS)

I. Preliminaries So “The Fundamental Question” is… Semantics is the study of meaning. “What is meaning?”

Semantic vs. Speaker’s Meaning Semantic meaning = meaning of a sentence independently of speaker’s quirks. Speaker meaning = what speaker intends when uttering a sentence. So more precisely, our question is: “What is semantic meaning?”

An Example I utter the sentence, “Don is the president,” but I mean that Ron Liebowitz is the president. The italicized sentence is the speaker’s meaning, but the quoted sentence is the literal or semantic meaning. I utter the sentence, “Don is the president,” but I mean that Ron Liebowitz is the president. The italicized sentence is the speaker’s meaning, but the quoted sentence is the literal or semantic meaning.

Why formal semantics? Formal semantics uses logical and mathematical tools to answer this question in a scientific manner. Formalization encourages the construction of precise theories of meaning. Precision is needed so as to avoid fudging a fit between theory and linguistic evidence. Formalization enables implementation of semantic theories in computational settings. This is important for integrating semantics with other fields, especially cognitive science.

II. Rejected Theories of Meaning A.Definitional theory B.Idea theory C.Social practice theory

Objection to the definitional view: the regress problem 1.A definition is composed of words. – For instance, the definition of “pizzicato” is composed of the words “plucking,” “a” “stringed” and “instrument.” 2.If a word’s meaning = its definition, then the words constituting the definition must be meaningful. – If the definition of “pizzicato” were “gleeb barl nub nub,” then “pizzicato” would be meaningless. 3.But this means that if word w 1 is defined by word w 2, then w 2 must be defined by some word w 3, which in turn must be defined by w 4, … 4.But this is impossible. 5.So a word’s meaning  its definition.

Holist Solution to the Regress Problem Suppose that the chain of definitions in the regress problem went something like this: w1w2 w4w3 Furthermore, each word is defined by its relationships to the other words. This is called semantic holism, since the meaning of one word depends on how it relates to the entire “network” of other words.

II.B. Idea Theory of Meaning A word’s meaning = its user’s concept For instance, I have the concept of WATER. The (my?) meaning of the word “water” is then the (my?) concept WATER. Idea theories face two challenges…

II.B.2. Psychological Differences Objection

II.B.2.a.Potential rebuttal to the Psychological Differences Objection Our concepts overlap significantly. In particular, if 2+ individuals both have a concept X, then X aims to describe the same set of objects. Ex. Bob and Christie both have a concept WATER, but Bob’s concept involves a mental image of the Pacific Ocean, and Christie’s with a glass of clear liquid. However, they both identify the same substance as water in all cases (let’s say through analogy with their respective mental images.) Then their common concept is the set things they classify as water.

II.B.2.b. Problem with this rebuttal It turns the Idea Theory into a “side-trip”. We can identify the meaning of “water” without appealing to Bob and Christie’s mental images, and simply with the set of objects that they classify as water.

II.C. Social Practice Theories of Meaning A word’s meaning = the rules governing its use in a social practice. Slogan: meaning is (correct) use Just as a chess-piece is defined by the permissible moves one can make with it, so is a word. In this case, the “moves” are actions, inferences, etc.

Recap Formal semantics seeks a precise, scientific answer to the question, ‘what is meaning?’ The definitional, idea, and social practice theories all seem to face problems on this front. Truth-Conditional Semantics (TCS) does not face these difficulties, and has become the dominant theoretical approach among linguists.

III. Truth-Conditional Semantics (TCS) A.Motivation B.Meanings and truth-conditions C.Key Terms D.Virtues of TCS

III.B. Meanings and truth-conditions So far, we’ve been focusing on the meanings of words. When strung together in the appropriate way, words constitute sentences. What are the meanings of sentences? A crucial aspect of understanding the meaning of a sentence is knowledge of the conditions in which that sentence is true, and of the conditions in which it’s false. Ex. The cat is on the mat.

III.C. TCS: Key terms TCS holds that all there is to meaning of a sentence = its truth-conditions. Truth-conditions = the conditions wherein a sentence is true/false. Truth-value = the truth/falsehood of a sentence. Note that because we can understand false sentences (as well as sentences with unknown truth-values), truth-conditions and truth-values should be distinguished. Only the former matter for meaning.

III.D. Virtues of TCS 1.TCS gives us plausible theories as to the meanings of logical vocabulary such as and, or, and not. 2.TCS allows us to define basic semantic concepts such as synonymy, contrariety, entailment, contradiction, and tautology. 3.We use language to gain information about the world so as to navigate it more effectively. TCS explains why we do this: if we understand the meaning of a sentence, then we know the conditions in which it’s true, so we can act accordingly.

III.D.2. More on TCS & key semantic concepts a.Synonymy: Two sentences are synonymous when they have identical truth conditions, i.e. they are true in exactly the same set of possible worlds. b.Entailment: A sentence p entails another sentence q if the truth of p guarantees the truth of q.

III.D.2. More on TCS & key semantic concepts c.Contrariety: Two sentences are contrary when they can’t both be true, i.e. when there is no overlap between the possible worlds in which they are true. d.Contradiction: Two sentences are contradictory if they can’t both be true and can’t both be false. – This differs from contrariety in that there may be cases in which contraries can both be false. – Ex. All students study logic is a contrary to no students study logic, but both may be false if some students don’t study logic and some students do study logic.

Recap Formal semantics seeks a precise, scientific answer to the question, ‘what is meaning?’ The definitional, idea, and social practice theories all seem to face problems on this front. Truth-Conditional Semantics (TCS) does not face these difficulties, and has become the dominant theoretical approach among linguists.