Presentation on theme: "Albert Gatt LIN 1180 – Semantics Lecture 8. Hyponymy and other relations Part 1."— Presentation transcript:
Albert Gatt LIN 1180 – Semantics Lecture 8
Hyponymy and other relations Part 1
Definition of hyponymy LIN Semantics Hyponymy is a relation of inclusion. Arrows can be interpreted as “IS- A” relations. Unlike taxonomic sisterhood, which is horizontal, hyponymy is vertical. ANIMAL MAMMAL BIRD CANARY SPARROW
Elements of hyponymy LIN Semantics If Y IS-A X then: 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
Transitivity -- illustration LIN Semantics A CANARY IS-A BIRD A BIRD IS-A ANIMAL Therefore, a CANARY IS-A ANIMAL ANIMAL BIRD SPARROW CANARY MAMMAL
Hierarchical representations and inheritance Semantics -- LIN 1180 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 ANIMAL BIRD Moves Eats breathes Flies Has feathers OSTRICH Does not fly
Levels of conceptual representation Semantics -- LIN 1180 Rosch et al propose 3 levels FURNITURE CHAIR ARMCHAIR TABLE Superordinate Or “top” level Basic level: This is the level we tend to use and think about Subordinate level: Much more specific
Properties of the basic level Semantics -- LIN The easiest to visualise: easier to imagine a CAR (basic) than a FIAT PUNTO (subordinate) 2. 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” 3. Names of basic-level categories tend to be morphologically simple Compare: spoon vs. teaspoon, soup spoon…
More properties of the basic level Semantics -- LIN high distinctiveness maximally different from other categories 5. strong within-category resemblance objects within the category resemble eachother more than they do objects outside the category 6. 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…
Special cases of taxonomic relations LIN Semantics 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.
Meronymy or part-whole LIN Semantics A different kind of taxonomic relationship. Arrows are interpreted as “HAS-A” ANIMAL BIRD WING LEG HAS-A IS-A HAS-A
Meronymy vs. Hyponymy LIN Semantics 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.
Member-collection relations LIN Semantics We often lexicalise names of collections of specific things: flotta (fleet) : a collection of ships mer ħ la (flock): a collection of sheep Native speakers know there is a member-collection relation: flotta (fleet) – vapur (ship) armata (army) – suldat (soldier) mer ħ la (flock) – nag ħġ a (sheep) Can be viewed as a special, lexicalised case of meronymy.
Are collections singular or plural? LIN Semantics 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?
Beyond the lexicon: Overview of sentence relations Part 2
In this lecture LIN Semantics Having looked in some detail at properties of the lexicon, we now turn to sentences. We discuss meaning relations between sentences truth conditions presupposition
Sentence relations LIN Semantics 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
Sentence synonymy LIN Semantics 1. My brother is a bachelor 2. My brother is an unmarried man (1) and (2) seem to have the same meaning (or almost... Cf. Our discussion of synonymy)
Entailment LIN Semantics 1. My sister assassinated the president. 2. 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: 3. My sister shot the president. 4. The president is dead. If (1) is negated, it no longer entails (2): My sister did not assassinate the president.
Important properties of entailment LIN Semantics 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.
How does entailment arise? LIN Semantics 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.
Contradiction LIN Semantics 1. My canary has just escaped from its cage. 2. My canary has never been in a cage. If (1) is true, then (2) cannot be true (and vice versa) (2) contradicts (1) 3. He is a murderer but he’s never killed anyone. (3) is also a contradiction
Tautology LIN Semantics 1. Albert is Albert 2. This classroom is this classroom. Both (1) and (2) are necessarily true In fact, both are highly uninformative sentences.