LIN 1180 – Semantics Lecture 8 Albert Gatt
Hyponymy and other relations Part 1 Hyponymy and other relations
Definition of hyponymy Hyponymy is a relation of inclusion. Arrows can be interpreted as “IS-A” relations. Unlike taxonomic sisterhood, which is horizontal, hyponymy is vertical. ANIMAL BIRD MAMMAL CANARY SPARROW LIN 1180 -- Semantics
Elements of hyponymy If Y IS-A X then: Inclusion: Transitivity: X is the superordinate or hypernym of Y Y is a subordinate or hyponym of X e.g. HUMAN is the hypernym of MAN, TOOL is the hypernym of CHAINSAW Inclusion: if Y is a hyponym of X then Y contains the meaning of X (plus something extra) e.g. MAN includes all the features of HUMAN, plus the specification of ADULT and MALE. Transitivity: if X IS-A Y and Y IS-A Z, then X IS-A Z LIN 1180 -- Semantics
Transitivity -- illustration A CANARY IS-A BIRD A BIRD IS-A ANIMAL Therefore, a CANARY IS-A ANIMAL ANIMAL BIRD MAMMAL CANARY SPARROW LIN 1180 -- Semantics
Hierarchical representations and inheritance A node in a conceptual network inherits some properties from its superordinate It can also add new properties of its own It can override properties of the superordinate Moves Eats breathes ANIMAL BIRD Flies Has feathers Does not fly OSTRICH Semantics -- LIN 1180
Levels of conceptual representation Rosch et al. 1976 propose 3 levels Superordinate Or “top” level FURNITURE Basic level: This is the level we tend to use and think about CHAIR TABLE Subordinate level: Much more specific ARMCHAIR Semantics -- LIN 1180
Properties of the basic level The easiest to visualise: easier to imagine a CAR (basic) than a FIAT PUNTO (subordinate) Used for neutral, everyday usage: we’re more likely to say “that’s a dog” than “that’s a dachshund” or “that’s an animal” Names of basic-level categories tend to be morphologically simple Compare: spoon vs. teaspoon, soup spoon… Semantics -- LIN 1180
More properties of the basic level high distinctiveness maximally different from other categories strong within-category resemblance objects within the category resemble eachother more than they do objects outside the category optimal level of informativeness: it’s more informative to say “x is a dog” than “x is an animal” but in most cases, saying “x is a dachshund” is too specific… Semantics -- LIN 1180
Special cases of taxonomic relations Sometimes, language exhibits special cases of relations that are: well-established and lexicalised seem to depend on an underlying taxonomy or hierarchy ADULT-YOUNG dog – puppy, duck – duckling, etc MALE-FEMALE woman – man, dog – bitch, drake – duck, etc NB: These pairs are often asymmetric. The unmarked case in the MALE- FEMALE is the MALE. We tend to use it for the name of the species. LIN 1180 -- Semantics
Meronymy or part-whole A different kind of taxonomic relationship. Arrows are interpreted as “HAS-A” LEG ANIMAL HAS-A IS-A WING BIRD HAS-A LIN 1180 -- Semantics
Meronymy vs. Hyponymy Meronymy tends to be less regular than hyponymy: NOSE is perceived as a necessary part of a FACE CELLAR may be part of HOUSE, but not necessarily Meronymy need not be transitive: If X HAS-A Y and Y HAS-A Z, it does not follow that Y HAS-A Z window HAS-A pane room HAS-A window ??room HAS-A pane Common-sense knowledge plays a very important role in acceptability of these relations. LIN 1180 -- Semantics
Member-collection relations We often lexicalise names of collections of specific things: flotta (fleet) : a collection of ships merħla (flock): a collection of sheep Native speakers know there is a member-collection relation: flotta (fleet) – vapur (ship) armata (army) – suldat (soldier) merħla (flock) – nagħġa (sheep) Can be viewed as a special, lexicalised case of meronymy. LIN 1180 -- Semantics
Are collections singular or plural? In many languages, there is the possibility of switching from: a view of a collection as a single entity vs. the “contents” of the collection as a group or set English: The band played well tonight. It drove the crowd nuts [SG] They drove the crowd nuts [PL] Maltese: L-armata rtirat (The army retreated.SG) ?L-armata rtiraw. (The army retreated.PL) Perhaps not as acceptable? Only with some nouns? LIN 1180 -- Semantics
Beyond the lexicon: Overview of sentence relations Part 2 Beyond the lexicon: Overview of sentence relations
In this lecture Having looked in some detail at properties of the lexicon, we now turn to sentences. We discuss meaning relations between sentences truth conditions presupposition LIN 1180 - Semantics
Sentence relations Just as lexical items stand in various relations to one another (hyponymy, etc), so do sentences: Relations between sentences arise due to: the lexical items in them their grammatical structure LIN 1180 - Semantics
Sentence synonymy My brother is a bachelor My brother is an unmarried man (1) and (2) seem to have the same meaning (or almost... Cf. Our discussion of synonymy) LIN 1180 - Semantics
Entailment My sister assassinated the president. The president is dead. (1) entails (2), primarily because of the meaning of assassinate. if (1) is true, then (2) must be true The following are not in an entailment relationship: My sister shot the president. If (1) is negated, it no longer entails (2): My sister did not assassinate the president. LIN 1180 - Semantics
Important properties of entailment A sentence p entails a sentence q if, and only if: q is true whenever p is true q is false whenever p is false This is why entailment is cancelled by negation. LIN 1180 - Semantics
How does entailment arise? Lexical, e.g. hyponymy My sister assassinated X X died. assassinate Y includes Y dies I bought a dog I bought an animal dog is a hyponym of animal Syntactic, e.g. active/passive My sister assassinated the president The president was assassinated by my sister. LIN 1180 - Semantics
Contradiction My canary has just escaped from its cage. My canary has never been in a cage. If (1) is true, then (2) cannot be true (and vice versa) (2) contradicts (1) He is a murderer but he’s never killed anyone. (3) is also a contradiction LIN 1180 - Semantics
Tautology Albert is Albert This classroom is this classroom. Both (1) and (2) are necessarily true In fact, both are highly uninformative sentences. LIN 1180 - Semantics