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  1. ENG2003 Semantics

  2. Semantics Semantics is the study of meaning. Once a sentence is built, how do we know what it means? Do the following sentences have meaning? The King of France is bald. There’s a unicorn in my backyard eating my flowers. The fireplace at the front of the classroom needs to be repaired. How long has it been since you’ve stopped smoking? (asked to someone who has never smoked)

  3. Linguistics in the 19th and 20th century: American Structuralism: Precise methodology for determining phonemes, allophones, morphemes, allomorphs Zellig Harris (Chomsky’s doctoral supervisor) later established precise methodology for syntax. The study of semantics (meaning) seemed quite different from the study of sounds and word structure – considered more philosophy than linguistics Early grammars of Native North American languages (북미 원주민 언어) from the 20th century did not discuss semantics Modern semantics: Frege (late 19th century) and Montague (1960’s) “The Semantics of Murder”

  4. There are two kinds of meaning that are typically relevant to linguistics Linguistic Meaning – The meaning conveyed by an utterance including its syntactic, morphological and phonological structure divorced from the speaker’s intentions. Speaker Meaning – The linguistic meaning of an utterance combined with the speaker’s intentions. “The door is behind you!” Linguistic meaning indicates location of the door. Speaker meaning indicates a hostile command to the addressee to leave. Speaker meaning can include sarcasm, irony and other metalinguistic speech acts. Semantics – linguistics meaning Pragmatics – speaker meaning

  5. Denotational Theory of Meaning The meaning of an expression is the real life object it denotes. [[X]] = “the denotation of X” [[Jo Sumi]] = Under a strict view of this theory, if an expression has meaning it must have a denotation. How do we interpret the following: [[the King of France]] [[the unicorn in my garden]] What is the denotation of a sentence? [[the first man on the moon]] = [[Neil Armstrong]] but these two phrases don’t mean the same thing… The notion of denotation has been developed into compositional semantics

  6. Sense Theory of Meaning Developed by Frege in the late 19th century Referring expression (R-expression) – an expression that picks out a real entity in the universe of discourse (not the real universe) A unicorn is eating my radishes. a unicorn, my radishes– both R-expressions It’s raining. it – not an R-expression The cat’s out of the bag. the cat – not an R-expression (no cat anywhere) John wants to be a doctor John – R-expression a doctor – not an R-expression rather it’s a predicate noun There is no doctor that John wants to be.

  7. Frege argued that R-expressions have a denotation as well as a sense – the way the R-expression is known to the user. Suppose you know the next door neighbour, Mary, but you don’t know that she’s the principal of the school down the street. Suppose she is arrested for stealing the children’s lunch money. Suppose also that you read about this in the news. Which of the following sentences could you utter? Which are true? The principal of the school down the street has been arrested. My next door neighbour, Mary, has been arrested. Both of these sentences are true. But you can utter only the first one. As far as you know, the second sentence is false. This is because my next door neighbour, Mary and the principal of the school down the street do not have the same sense for you.

  8. Moving beyond noun phrases, Frege argued that sentences have a sense, too. The sense of a sentence is the set of conditions under which it is true. The denotation of a sentence is either “true” or “false” (1 or 0, respectively) [[Seoul is the capital of the Republic of Korea]] = 1 [[Busan is the capital of the Republic of Korea]] = 0 Thus, sentences have various truth conditions.

  9. UseTheory of Meaning Developed by Wittgenstein in the mid 20th century The meaning of an expression is its use in the community. Again, the notion of “use” is too vague for this proposal to be testable. The Fregean programme is the dominant theory followed in many schools of thought, but the issue is by no means settled. More on Frege NPs denote entities S denotes {0, 1} (the set of truth values) What do predicates (such as VP) denote? A predicate is a function…a set A predicate must take a subject to make a complete sentence – it says something about the subject.

  10. The predicate is incomplete without the subject. The predicate maps the subject to a truth value. John smokes John – R-expression smokes – predicate, the set of people for whom the statement X smokes is true. So, if John is a smoker – i.e., a member of the set indicated by the predicate “smokes”, then what is the denotation of John smokes? [[John smokes]] = 1

  11. Compositional Semantics build sentence meaning from syntactic structure [[S]] = [[NP VP]] [[NP]] – entity [[VP]] – predicate with one empty slot…a function with one argument takes an entity as an argument and returns a truth value: 1 = true 0 = false Thus, the denotation of [S NP VP] is true if NP is a member of VP. [[smokes]] = the set {x|x smokes} | = such that [[Ann]] = the person named Ann fill the entity in for the variable: [[Ann smokes]] = 1 iff Ann smokes

  12. [[likes Fred]] = the set {x|x likes Fred} … the set of people(animals?) who like Fred What is the denotation of a transitive verb? -compound function [[like]] = the set {y| the set {x| x likes y}} [[Bill likes Fred]] = 1 iff Bill likes Fred start with the verb: [[likes]] fill in outer variable, y, with Fred [[likes Fred]] = the set {y| the set {x| x likes y}} (Fred) = the set {x | x likes Fred} [[Bill likes Fred]] = the set {x | x likes Fred} (Bill) Fill in Bill as x = 1 iff Bill likes Fred

  13. Semantic Relations among Words Synonymy If two words have the same or nearly the same meaning in some or all contexts, then these words are said to be synonyms. We went to Halifax for our vacation. We went to Halifax for our holidays. “Holidays”, however, can also refer to Christmas, New Years, etc. “Vacation” does not have this meaning. Nevertheless, they are still considered synonyms since they have nearly identical meanings in at least one context. It is rare for two words to have identical meanings in all possible contexts. 흑색 검은색 spit expectorate

  14. Semantic Relations among Words Synonymy John killed the president. John murdered the president. John assassinated the president. John killed the mosquito. #John murdered the mosquito. #John assassinated the mosquito. John killed his neighbour. John murdered his neighbour. #John assassinated his neighbour. The object of kill can be any living thing. The object or murder is typically human. The object of assassinate is typically a famous person.

  15. Semantic Relations among Words Antonymy If two words have partly opposite meanings in at least some contexts, then these two words are said to be antonyms. This room is very dark. This room is very light. These two words are not antonyms in all contexts. John has a dark personality. # John has a light personality. Pat is a boy. Pat is a girl. 규민은 남자야규민은 여자야 boy and girl differ in gender, but they both refer to humans. They are still antonyms despite the fact that they share some parts of meaning.

  16. Semantic Relations among Words Polysemy and Homophony We use the term form to refer to the phonological content of a word. write and right have the same form bow (=bend over) and bow (hair ornament) do not have the same form If two meanings of a given form have related meanings, then the form associated with each meaning is polysemous. This lamp is very bright. That student is very bright. bright (=light) and bright (=intelligent) have related meanings (one is a metaphorical extension of the other) – These two sense of bright are polysemes John works in a bank. John docked his boat at the bank. financial institution edge of a river. These meanings are completely unrelated. – The two words bank and bank are homophones.

  17. Semantic Relations among Words Polysemy and Homophony The distinction between polysemy and homophony is often difficult to make. It involves having some knowledge of the etymology of the word. Homophonous words are often listed separately in the dictionary. Ultimately, there is often no clear distinction and there are many grey areas. Note that many homophonous words actually derive from a common source…but so much time has passed that the words are typically categorized as distinct but homophonous words: flour flower bank bank mug mug mug (coffee cup, rob, ugly face/picture)

  18. Semantic Relations among Sentences Paraphrase Two sentences that have the same meaning in at least one context are paraphrases of each other. Two sentences have the same meaning if they have the same truth conditions. The police chased the burglar. The burglar was chased by the police. 민수가 사과를 먹었다. 사과를 민수가 먹었다.(scrambling – change in order of phrases) Both of sentences in each pair have the same truth conditions. In other words, it is impossible for one of these sentences to be true and for the other to be false.

  19. Semantic Relations among Sentences Paraphrase Sometimes, a sentence can be ambiguous, in which case a paraphrase can be equivalent to one of the meanings. John ate the apple in the kitchen. John ate the apple that was in the kitchen. John’s eating of the apple took place in the kitchen. These two paraphrases disambiguate the original sentence. If two sentences have exactly the same truth conditions, they are said to be truth-conditionally equivalent. This is the case for the burglar examples on the previous slide, but not the apple in the kitchen examples above.

  20. Semantic Relations among Sentences Paraphrase Note that not all examples of passives give rise to paraphrases. The editor didn’t discover many errors. Many errors weren’t discovered by the editor. These two sentences have quite divergent meanings. Likewise, scrambling in Korean can give rise to different meaning. 누군가 많은 사람을 비판했다. 많은 사람을 누군가 비판했다.

  21. Semantic Relations among Sentences Ambiguity Newspapers are notorious for ambiguous headlines: British left waffles on Falklands Iraqi head seeks arms Stolen painting found by tree Garden Path Sentences These are sentences which start out with one structure but end up having another. They are not ambiguous. The man who hunts ducks out on weekends. The cotton clothing is usually made of grows in Mississippi.

  22. Semantic Relations among Sentences Truth Properties A sentence is true if the truth conditions are satisfied in the real world (called empirically true in the textbook). John ate an apple. This sentence is true iff John ate an apple and is false otherwise. Tautology A tautology is a statement that is logically true under every possible situation. If John is sick and Mary is sick, then John is sick. Contradiction A contradiction is a statement that is logically false under every possible situation. Some people that are sick are not people.