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CTL5403  SEMANTICS and DISCOURSE

Haihua PAN (Dr.), CTL, CityU., HK

Office: Rm B7610; Phone: 2788 8795; Email:  cthpan@cityu.edu.hk

Word Meaning, Sentence Relation and Truth

1.  Grammatical Categories

• names, common nouns, pronouns, logical words, etc.

2.  Lexical Relations

• Homonymy: unrelated senses of the same phonological word. Homographs (written) vs. homophones (spoken)

• Polysemy: related senses of the same word. They are listed in the same lexical entry in the dictionary

• Synonymy: different phonological words with same or similar meaning. may belong to different registers: formal, colloquial, literary, etc.

• Opposites (Antonymy):

        --- simple antonyms (complementary or binary antonyms), e.g., dead vs. alive, pass vs. fail, etc.

        --- gradable antonyms: not binary antonyms, e.g., rich vs. poor, slow vs. fast, etc.

        --- reverse: opposite directions, e.g., left vs. right, up vs. down, come vs. go, pull vs. push, etc.

        --- converse: alternative viewpoints, e.g., own vs. belong to, employer vs. employee, etc. Only those items that observe the following rule form a converse relation: given two nouns X and Y, if X and Y form one relation specified by one of the two items in question, then they can be swapped when using the other item. For example, if X is the employer of Y, then Y is the employee of X. We can conclude that employer and employee form a converse relation.

        --- taxonomic sisters: e.g., orange, blue, yellow, etc.

• Hyponymy: a relation of inclusion, e.g., tool includes hammer, saw, chisel, etc. The general term is called superordinate or hypernym.

• Meronymy: describe part-whole relation.

• Member collection: unit vs collection, e.g. book vs library, ship vs. fleet, etc.

4.  Derivational Relations

• causative verbs: a state vs. beginning or change of state, e.g. red vs redden, wide vs widen, etc.

• agentive nouns: derived from verbs with endings -er or -or, e.g. walker, murderer, commentator, etc.

    Elsewhere condition: a general condition that applies only if the more specific conditions do not apply.

    English comparative formation: for two syllable adjectives, add -er, but for more than two syllable adjectives add more.       But words like glad, apt, etc. we have to use more. Hence the condition for two syllable words is the following:

    --- for words like glad, apt, etc., add more;

    --- otherwise, add -er.         <---------- this part is the else where condition.

5. Logic and Truth, Necessary Truth, Analytic Truth, etc.

• Truth value: semantists call a sentence's being true or false its truth value.
• Truth conditions: the facts that have to obtain in reality to make a sentence true or false.
• Truth tables for logical operators: conjunction and, disjunction or (inclusive), exclusive or, material implication (or conditional), biconditional, and negation.
• In a conditional sentence like if p then q, p and q are the antecedent and consequent, respectively. P is a sufficient condition for q but not a necessary condition. I.e. even though p is false, it is not necessarily the case that q is false.
• Conditionals: conditional (if p then q), biconditional (if p then q and if q then p, or p iff q, where iff means if and only if), and counterfactual.  In a biconditional sentence q iff p, p is the necessary condition for q.
• Necessary truth: cannot be denied (Leibniz's distinction), e.g. mathematical laws like 2 + 2 = 4, either he is alive or he is dead.
• Contingent truth: con be contradicted, depending on the facts.
• Tautology: always true. It is also analytic if the truth follows from the sentence meaning only, i.e., it does not depend on the things outside of the sentence.
• A synthetic statement is a statement true or false, depending on whether it accords with the facts of the world.
• A priori truth, is the truth that does not depend on our experience. It is contrasted with posteriori truth which can only be known on the basis of the empirical testing.

    Question: what is the relationship between synthetic, analytic, a priori, posteriori, necessary truth?

6. Entailment and Presupposition

• Entailment: p entails q = if p then q and if not q then not p. Hyponymy always gives us entailment relation, e.g. dog entails animal: if x is a dog, then it is an animal and if x is not an animal, then it is not a dog.
• Paraphrase: mutual entailment.
• Two approaches to presupposition: (a) as truth relation; and (b) as a strategy of the speaker to organize the information for maximal clarity.
• Presupposition failure: the presupposition of a sentence is not true in the real world.   Note that presupposition failure is a problem for approach (a) but not necessarily so for (b).
• Presupposition trigger: cleft or pseudo-cleft sentences, subordination, lexical verbs like regret, realize, etc.
• Projection problem: some presupposition does not survive when embedded in a larger context.
• Differences between entailment and presupposition: (a) negating the entailing sentence, then the entailment fails, but negating the presupposing sentence, the presupposition survives; and (b)  presupposition changes with context, while entailment does not.  We have semantic and pragmatic presuppositions the latter of which is related to common ground (Stalnaker 1974), and accommodation (Lewis 1979).