Lexical Semantics Flashcards
(18 cards)
What is Entailment? And how do we know whether a sentence entails the other?
The truth of one sentence requires the truth of the other.
The way we check this is by using:
1- Contradiction: Ibrahim is a good linguist, Ibrahim is NOT a good linguist.
2- Redundancy: Ibrahim is a good linguist, AND Ibrahim is a linguist.
Its symbol is: ⊨
What is implicature?
Sentence B is an implicature of sentence A if B is what is expected when A is uttered (not necessarily true).
EX: “that was a good meal” +–> “that was not a great meal” is what we would expect since we believe it is on the “good” level.
How do we test implicatures?
1- Defeasibility test: If A implies B, then B can be cancelled.
What are the four Categories of Expressions in LP?
1- Individuals: These refer to objects or entities (e.g., “Alice,” “the cat”).
2- Predicates: These represent properties or relations (e.g., “is red,” “is taller than”).
3- Formulae: These are complete logical statements (e.g., “The cat is black”).
4- Operators (Connectives): These are logical symbols like “and,” “or,” “not” that combine formulae.
The individuals, predicates, and formulae are divided into two types.
Constants: Fixed expressions with a specific meaning (like content words in natural language: “table,” “run,” “Ethel”).
Variables: Expressions without a fixed meaning; they act as placeholders (like pronouns: “she,” “they”).
Example: In “x is tall,” “x” is a variable, while in “Alice is tall,” “Alice” is a constant.
What is Valency?
The number of arguments that a predicate takes
How do we classify predicates, and how do we represent the number of arguments it takes?
All are classed as members of the logical category “pred”. We show the number of arguments by using a subscripted number to the right of “pred”
How many arguments can a predicate take?
unlimted.
How do we write a formula that combines a predicate with its argument?
Pred n ( a, b, c, d …..)
Why are grammar fragments used in formal semantics?
To develop a specific and precise theory about the meaning of the expressions they analyse.
How can a grammar generate a sentence?
iif there is a derivation from S using the syntactic rules and lexicon.
What is derivation?
Is the sequence of rules applications that transform S into the final sentence. The process only stops when there are no more categories (NP, VP) left.
Ex:
1-S
2- Npr Vt [+Fin] Np2
3- Npr Vt [+Fin] Np2
4- Npr Vt [+Fin] the N
5- Joan poisoned the man
Why is it important to use derivations and trees?
Because translating from English to Lp is done not on string of words that makes S, but rather on the syntactic structure of those S.
What are the two steps of translating sentences into Lp?
1- Providing grammar fragments
2- Translation
How do we translate from G1 into Lp?
1- we have to associate the syntactic categories in G1 with their corresponding logical categories in Lp.
Ex: 1- All proper and definite nouns= constant individuals.
2- Verbs= predicates (subcategoried according to their number of arguments)
3- Adjectives/predicatives= predicates (because they behave similarly to verbs, since they ascribe
How do we interpret formulae in Lp?
In terms if its truth conditions
What are the two parts to the interpretation procedure in Lp?
1- The model: provides the “world” (ontology) and links language to it (denotation function).
2- The model theory: governs how meanings combine and determines truth conditions.
The first part of interpretation is the model, explain
Interpretation occurs in relation to a representation of a state of affairs, aka the model. It consists of two parts:
1- Ontology: 1.1 defines what exists in the world (or the relevant situation).
1.2 Includes both concrete entities (e.g., physical objects) and abstract entities (love)
1.3 It categorises entities into types (e.g., abstract vs. concrete) to capture semantic distinctions.
2- Denotation Assignment Function (Naming Function): 1.1Maps basic expressions(nouns, verbs, adjectives) to entities/relations in the ontology. EX: The word “book” might denote a specific book in the model. The verb “read” might denote a relation between entities (e.g., a child reading a book).
