Decompositional Sentence Semantics

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Week 3: Decompositional sentence semantics



Introduction Last week, we looked at the meaning of individual

words

This week, we consider the meaning of word strings,sentences

Just as the meaning of a word may lie in its componentparts (semantic features) so the meaning of a sentence

may lie in its component parts (words) That is, we may take a decompositional approach to

both lexical and sentential semantics



Introduction Principle of compositionality for sentence meaning:

The meaning of a grammatically complex form is a compositionalfunction of the meanings of its grammatical constituents

Principle incorporates three separate claims:1. The meaning of a complex expression is completely determined by the

meanings of its constituents

2. The meaning of a complex expression is completely predictable by general rules from the meanings of its constituents

3. Every grammatical constituent has a meaning which contributes to themeaning as a whole

(Cruse 2004: 65)



Introduction Principle arises from the fact that sentence meaning

cannot be stored in a mental dictionary since there arean infinite number of possible sentences

Sentence meaning must be derived by generative, rule-based procedures (algorithms) operating on inputs(lexical entries)

The only way that such a system can function is if itsoutput, i.e. sentence meaning, is no greater than thesum of its parts, namely words



Modes of Combination Words can be combined in different ways to yield more

complex meanings In additive modes of combination, the meanings of

the constituents are simply added and both remainunchanged:

[A man and a woman] entered the room and sat down Jane is [tall and fair]

(Cruse 2004: 66)



Modes of Combination In interactive modes of combination, the meaning of

at least one constituent is significantly altered in the

combination There are two types of interactive modes of

combination:

Endocentric whereby the resultant meaning is of the

same basic type as one of the constituents Exocentric whereby the resultant meaning is of a

different basic type from either of the constituents



Modes of Combination Boolean combinations are the most basic type of

endocentric interactive combinations For example, the meaning of red hat, i.e. things that

are both red and hats, is constituted by theintersection of red and hat

The denotation of hat is limited by its combination with red, but what a red hat denotes is of the sameontological type as what a hat denotes



Modes of Combination A further type of combination involves relative

descriptors, e.g. a large mouse

The meaning of large mouse is not something which isboth large and a mouse

Its meaning here is something like “larger than theaverage X” where X is the class of things to which the

word large is applied The meaning of mouse is delimited by its

combination with large but the meaning of large isalso affected by its combination with mouse



Modes of Combination Negational descriptors modify the meaning of their

head, e.g., a fake gun is not something that is both afake and a gun

Indirect combinations involve a more complexprocess

For example, a beautiful dancer can be read as a

Boolean combination (i.e. a dancer who is beautiful) orin such a way that beautiful becomes an adverbialmodifier rendering the meaning someone who dancesbeautifully



Modes of Combination In all of the endocentric examples so far, the basic

ontological type remains the same However, in exocentric combinations, the ontological

type changes

For example, the preposition ‘in’ denotes a relation and

‘the box’ denotes a THING, but in the box denotes aPLACE



Modes of Combination Notice also that whilst the meaning of a given

constituent may be modified as a function of itscombination with other particular constituents,precisely because the modification of the constituentis rule-governed, the meaning of the whole is stillpredictable from the meaning of its parts



Problems with decomposition There are some obvious problems with a purely

decompositional approach to sentence meaning

Firstly, it is necessary but not sufficient to know themeanings of the words in order to know the meaningof the sentence:

a) The dog bit the man

b) The man was bitten by the dogc) The man bit the dog



Problems with decomposition Whilst (a) and (b) express the same proposition, (c)

expresses an entirely different proposition, yet eachsentence contains the same set of words

The meaning of the sentence must therefore extendbeyond the semantics of its constituent parts to

include its syntactic structure



Problems with decomposition The importance of syntactic structure for meaning can

be seen in structurally (as opposed to lexically)ambiguous sentences:

1) They are visiting relatives

2) Flying planes can be dangerous

3) The beautiful girls dress attracted my attention

(Jaszczolt 2002:60)



Problems with decomposition The simple order of conjuncts can also affect meaning:

a) They got married and had a baby

b) They had a baby and got married

(a) means something different to (b) because themeaning of and, in certain environments, includes atemporal ordering of events



Problems with decomposition Further problems for decompositional approaches to

sentence semantics are to be found inconventionalised expressions

For example, the meaning of phrasal idioms cannotbe gathered from their component parts:

Jane pulled Mary’s leg about her new boyfriend



Problems with decomposition The non-compositional nature of phrasal idioms can

be seen through various kinds of tests, includingsubstitution for synonyms:

* Jane tugged on Mary’s lower limb about her newboyfriend

Also, elements are not separately modifiable:

Jane pulled Mary’s left leg about her new boyfriend



Problems with decomposition Frozen metaphors are similarly non-compositional

but they differ in one important respect from phrasalidioms

The non-literal meaning is retained or is at least stillrecoverable, in synonym substitutions:

a) The ball is in your court nowb) The ball is on your side of the net now



Problems with decomposition The meaning of a compound noun is often to some

extent predictable from its component parts

However, not entirely and there may be some sense in which they are idiomatic

For example, tablecloth and dishcloth

There is no way of predicting that a tablecloth is used

to cover a table, but a dishcloth is used to wipe dishes



Problems with decomposition Differences in interaction between a modifier and its

head noun can similarly be seen in adjective + nouncombinations:

a) A red hat

b) A red book

c) A red apple

Here, the modifier applies to a different active zone(Langacker 2008) of the head noun and, again, this isnot predictable from any sort of formal rule



Thematic roles One way in which the semantic structure of a sentence

has traditionally been analysed is in terms of semanticconstituents known as thematic roles

These include: AGENT, PATIENT, THEME, EXPERIENCER, BENEFICIARY , INSTRUMENT, LOCATION, SOURCE, GOAL

For example, the structure of Henry raised the car with a

jack can be said to consist of the following: V raised [ AGENT, PATIENT, INSTRUMENT]



Thematic roles Assigning roles is not always straightforward for

example:

Chloe received a gift of f lowers – goal or beneficiary?

John smashed the cup – patient or theme?

The computer switched itself off - agent?



Thematic roles Actor: “expresses the participant which performs,

effects, instigates, or controls the situation demandedby the predicate” (Foley and Van Valin 1984: 29)

Agent: “the intentional initiator of some action. Hereintention means sentient or capable of acting with

violition” (Saeed 2009: 153) E.g. Mary crashed the car



Thematic roles Every agent is an actor but not every actor is an agent

It can be determined whether an entity is an agentiveactor with a simple test (after Jackendoff):

If words such as deliberately, on purpose, intended toetc can be used in the sentence, then the actor isagentive

The wind intended to wreck my fence



Syntax/semantics interface Thematic roles are one area in which syntax and

semantics can be seen to interface

For example, the semantic role of AGENT is typically (though not necessarily) encoded in the subject, therole of PATIENT in the direct object and the roles of instrument and location are both typically encoded inthe indirect object

John broke the window with the ball



Syntax / semantics interface In the passive voice, the roles change:

E.g. The window was broken by John

Sometimes the verb causes the roles to move:E.g. Paul broke the concrete with a pickaxe

The pickaxe broke the concrete

The concrete broke

The verb break allows the agent, instrument andpatient roles to occupy the subject position



Motion/Location events In a similar but not identical vein, Talmy (e.g. 1985)

identifies a set of semantic components for sentencesassociated with verbs of motion / location including:

Figure An object located or moving with respect toanother (the Ground)

Motion The presence of motion or location in the event

Path The course followed or the site occupied by the

Figure with respect to the Ground

Manner The type of motion involved



Motion/Location eventsFor example:

Motion:

Charlotte swam away from the crocodile

[FIGURE] [MOTION/MANNER ] [PATH] [GROUND]

Location:

The banana hung from the tree

[FIGURE] [MANNER ] [PATH] [GROUND]

Saeed 2009: 274

Components conflated in different ways in differentlanguages



Conclusion The meaning of a sentence may be generated as a

combinatorial function of its constituent parts, words

However, there are at least some cases in which themeaning of a sentence cannot be predicted from themeaning of its parts

The semantic structure of sentences has been analysed

in terms of different sets of semantic components Questions remain over the psychological status of

these components



Reading Cruse, A. Chapter 4 on compositionality

Saeed, J.I. Chapters 6 and 9.4 – 9.5



BibliographyCruse, A. (2004). Meaning in language: an introduction to semanticsand pragmatics (2nd Ed.). Oxford University Press: Oxford.

Foley, W. and Van Valin, R. (1984) Functional syntax and universal

grammar. Cambridge University Press: Cambridge Jaszczolt, K.M. (2002). Semantics and pragmatics: meaning in languageand discourse. Pearson Education: Harlow.

Saeed, J.I. (2009). Semantics (3rd Ed.). Wiley-Blackwell: Chichester.

Talmy, L. (1985). Lexicalisation patterns: semantic structure in lexical

forms. In: Shopen, T. (ed.) Language typology and semantic description, vol 3: 57-149. Cambridge University Press: Cambridge

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Decompositional Sentence Semantics

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