Post on 06-Apr-2018
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Semantics
Topic 5
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Topics in Semantics
utterance & sentence
sense & reference
sense relations
synonomy/antonymy/hyponymy/homonymy
paraphrase/contradictory/entailment
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Conversational Implicature- Grice's 4 maxims
Speech Acts
- Performatives
- direct vs. indirect speech acts
Locution/Illocution/Perlocution
Presupposition
Deixis
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Part 1. Semantics
Semantics: the study of the linguistic meaning
(of morphemes, words, phrases, and sentences)
in language
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an introductory passage"...that shows that there are three hundred and sixty four days when you
might get un-birthday present.
"Certainly," said Alice.
"And only one for birthday presents, you know. There's glory for you!"
"I don't know what you mean by 'glory.'" Alice said.
Humpty Dumpty smiled contemptuously. "Of course you don't - till I tell you.I meant 'there's a nice knockdown argument for you.'"
"But 'glory' doesn't mean 'a nice knockdown argument," Alice objected.
"When I use a word," Humpty Dumpty said in a rather scornful tone, "itmeans just what I choose it to mean - neither more nor less."
"The question is," said Alice, "whether you can make words mean so manydifferent things."
"The question is," said Humpty Dumpty, "which is to be master - that's all."
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* speaker meaning vs.
sentence meaning
speaker meaning: what a speaker means (i.e.
intends to convey) when he uses a piece of
language
sentence meaning (or word meaning):
what a sentence or word means.
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comparing two conversational
exchanges (I and II) Conversation I
A: "Nice day."B: "Yes, a bit warmer than yesterday, isn't it?"
...B: "Have you been away on holiday?"A: "Yes, we went to Spain."B: "Did you? We're going to France next month."
A: "Oh. Are you?That'll be nice for the family. Dothey speak French?"B: Sheila is quite good at it, and we're hoping Martin
will improve."A: "I expect he will. I do hope you have a good time."
...
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Conversation IIHusband: "When I go away next week,
I'm taking the car."Wife: "Oh. Are you? I need the car here to
take the kids to school."Husband: "I'm sorry, but I must have it.
You'll have to send them on the bus."Wife: "That'll be nice for the family.
Up at the crack of dawn, and not hometill mid-evening! Sometimes you are veryinconsiderate."
Husband: "Nice day."
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The same sentences are used by different speakerson different occasions to mean (speaker meaning)different things. -- the importance of speaker
meaning. The speaker meaning sometimes can completely
override the sentence meaning.
e.g. The prime minister of the country is made ofiron.
This suitcase is killing me.
Still people cannot have an ordinary conversationwithout knowing the meanings of the words theyare using.
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Therefore, both sentence meaning and speaker
meaning have to be taken seriously in order to
set up a proper and complete theory ofmeaning.
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utterances () and
sentences ()
Read the following aloud.
Honesty pays
Read it again.
Then youve made two distinct utterances usingone and the same sentence.
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An utterance is any stretch of talk, by one person,
before and after which there is silence on the part of
that person In other words, utterances are physical objects or
events that will go away once they are made. Andutterances are affected by the speaker, place, and timefactors.
On the other hand, a sentence is an abstract entity, thatis neither a physical event nor a physical object. It is astring of words put together by the grammatical rules oflanguage and the result of abstract thinking
e.g. All the plays titled Macbeth start with the samesentence, but with different utterance, every time.
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reference and sense In everyday conversation, the words meaning, means, mean,
meantetc. are sometimes used to indicate reference andsometimes to indicate sense
reference: the thing(s) in the world that are picked out bythe linguistic expression
e.g. John is in the beech tree.identifies identifies
a person a thing
sense: not the concrete things in the world but the abstractentity/meaning represented by the linguistic expression
e.g. John vs. the man sitting next to Mary
- these two expressions can have the same reference, butnot the same sense
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Depending on whether a given expression
always refers to the same thing or not, it is said
to have either constant or variable reference. constant reference:
John, The People's Republic of China, the 5th
President of the Republic of Korea, Oct 12,2000, Halley's Comet
variable reference:
my friend, your left ear, this page, the presentpresident of the Republic of Korea, yesterday
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Referential theory of meaning
The meaning of a linguistic expression is its
reference
The Rule of Identity
The expressions with the same meaning can beexchanged without causing any meaning change.
Frege's notion of meaning
There are two levels of meaning- sense and reference
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Opaque context
the same expression yields different meanings
when uttered in some specific contexts
e.g. Dennis thinks that ....
Clinton had an affair with Lewinsky.
The man next to Dennis had an affair with Lewinsky.
Dennis believes that Clinton had an affair with Lewinsky.
Dennis believes that the man next to him had an affair withLewinsky.
Opaque contexts show us that there is more to meaningthan just reference and we need sense in addition toreference if we want to have a more pertinent view of
meaning.
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Every expression that has meaning has sense,
but not every expression has reference
(e.g. almost, nearly, and, but, very)
A referring expression is any expression used in
an utterance to refer to something or someone
(or a clearly delimited collection of things or
people), i.e. used with a particular referent in
mind.
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analytic vs. synthetic sentence
An analytic sentence is one that is necessarily true, as
a result of the words in it (tautologies).A synthetic sentence is one which is not analytic, but
can be sometimes true, sometimes false, dependingon the circumstances.
Cats are animals.Bachelors are unmarried.
The boy is his own father's son.
Bachelors cannot form lasting relationships.
No cat likes to bathe.
John is nine years old.
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contradiction: a sentence that is necessarily
false, as a result of the senses of the words in it
This animal is a vegetable.
This girl is her own mother's mother.
John killed Bill, who remained alive for many
years after.
[disregarding the figurative use]
e.g. That man is not a human being.
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Sense relations
Why sense relations?
Sense is an abstract concept and hence it is not easy todefine exactly what sense is.
e.g. What is the sense of the word 'cat'?
1) all the cats that can be referred to by this word?
2) the sum total of the various properties about cats?
has four legs & two ears, makes a 'meow' sound,of some size & weight (but how big?)
3) ...
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Why sense relations? (2)
Hence, instead of defining sense directly,
researchers tried to find the sense of some
expressions through the sense relations, which
concern the relative positioning of the
expressions in regard to other expressions.
This might be a more effective way of
illuminating the meaning of sense.
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Synonymy: the relationship between two predicatesthat have the same sense (with strict definition, it ishard to find real synonyms)
The thief tried to conceal/hide the evidence.
I'm going to purchase/buy a new coat.
John's father is very stubborn/obstinate.
You have my profound/deep sympathy.It's a very wide/broad street.
How many kids/children have you got?
He comes to see us every fall/autumn.
(abstracting away from any stylistic, social ordialectal associations)
and freedom-liberty, boot/trunk
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Paraphrase: a sentence which expresses the sameproposition as another sentence is a paraphrase ofthat sentence
(paraphrase is to sentences as synonymy is topredicates)
Bachelors prefer red-haired girls.
Unmarried men prefer girls with red hairGirls with red hair are preferred by
unmarried men
John sold the book to Mary's sister.
Mary's sister bought the book from John.
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What is important is whether the sentences in
concern can have different truth conditions. If
not, they are paraphrases of each other.
word:synonym = sentence:paraphrase
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Hyponymy:a sense relation between predicates (or sometimeslonger phrases) such that the meaning of one
predicate (or phrase) is included in the meaning ofthe other.
e.g.
honesty is the hyponym of virtue.fear-emotion/cow-animal/
- synonymy is a special case of hyponymy in thesense that two synonyms are hyponyms of eachother.
E il
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EntailmentA proposition X entails a proposition Y if the truth of Yfollows necessarily from the truth of X. (A sentenceexpressing proposition X entails a sentence expressing
proposition Y if the truth of Y follows necessarily from thetruth of X)
John killed Bill entailsBill died.
John ate all the apples. entails Someone ate all the apples.
- Does [John cooked an egg] entail [John boiled an egg] orthe other way around?
John boiled an egg - John cooked an eggI saw a boy - I saw a human being
John stole a car - John took a car
I ran to the house - I went to the house
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transitivity of entailment
If A entails B and B entails C, then A entails C
John likes all the animals.
John likes all the cats.
John likes all small cats.
- Paraphrase may be a special case of entailment in the
sense that paraphrase is symmetric entailment.
It is hard to lasso elephants. -
Elephants are hard to lasso.
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the relationship between hyponymy and entailment
A Btulip flower
sheep animal
steal take-------hyponymy--------->
A B
Henry was chewing a tulip Henry was chewing a flowerDenis got savaged by a sheep Denis got savaged by an animal
David stole a pound of beef David took a pound of beef.
--------entailment--------->
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the Basic Rule of Sense Inclusion
Given two sentences A and B, identical in everyway except that A contains a word X where B
contains a different word Y, and X a hyponym
of Y, then sentence A entails sentence B.
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systematic exceptions
1) not
A Henry was not chewing a tulip
B Henry was not chewing a flower
Denis didn't get savaged by a sheepDenis didn't get savaged by an animal
David didn't steal a pound of beef
David didn't take a pound of beef.A
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2) all
A Henry was chewing all my tulips
B Henry was chewing all my flowers
A All Denis's sheep have foot-rot
B All Denis's animals have foot-rot
A Mary colored all the square shapes purple
B Mary colored all the rectangular shapes
purple.A
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3) gradable adjectives
A John saw a big mouseB John saw a big animal
A tall pygmy came in
A tall person came in.We went in a small bus.
We went into a small vehicle.
That was an expensive sandwich.That was an expensive meal
-------no entailment----------
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Oppositeness of meaning
(antonymy)
There is no simple meaning of antonymy as words
may be opposite in meaning in different ways,
and some words have no real opposites
between predicates: binary antonyms/
converses/gradable antonyms/
multiple incompatibility
between sentences: contradictory
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1. binary antonyms (compelmantarity); predicates which come in pairs and between them
exhaust all the relevant possibilities; they are
characterized by the fact they divide a conceptual domaininto two mutually exclusive compartments, so that whatdoes not fall into one of the compartments mustnecessarily fall into the other"
e.g. true-false, male-female, dead-alive,
married-unmarried
but not the following hot-cold, love-hate, thick-thin, buy-sell
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2. converses: (=relational opposites)
If a predicate describes a relationship between two things(or people) and some other predicate describes the
relationship obtained when the two things (or people) arementioned in the opposite order, then the two predicatesare converses of each other.
e.g. parent and child are converses , because if X is theparent of Y, then Y is the child of X
(below-above, grandparent-grandchild, own-belong to,greater than-less than)
converses applying to examples containing
three objectsbuy-sell, borrow-lend, give-take,
e.g. if X borrows something from Y, then Y lendssomething to X
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3. multiple incompatibility
There are more than two members in a
semantic system that are mutuallyincompatible
spring-summer-winter-fall
Sunday-Mon.-Tues-Wed-Thurs-Fri-Sat.
names of plants
names of metals
4 d bl
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4. gradable antonyms:
two predicates are gradable antonyms if they areat opposite ends of a continuous scale of values (a
scale which typically varies according to thecontext of use)
hotand coldare gradable antonyms since there aremany intermediate levels such as warm, lukewarm,cool, tepid...
also hot-coldare relative to the context ('hot' in
weather may be 'cold' in cooking)
e.g. tall-short, long-short, clever-stupid, love-hate
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A good test for gradability is whether theadjective can be modified by very, very much,how, how much.
e.g. How tall is he? He is very tall.
*How dead is he? *He is very dead.
Also the predicate on the positive side orupper scale is used in the unmarked question.
:How expensive is the car?How tall is he? How
far is it from here? How high is it?
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Contradictory
A proposition is a contradictory of another
proposition if it is impossible for them both to betrue at the same time and of the samecircumstances.
e.g. This beetle is alive vs. This beetle is dead.Mary is Ann's parent. vs.Mary is Ann's child.
John loves California vs.John hates California.
but,John owns three male cats. vs.John owns threefemale cats.
Some people love California vs. Some people hateCalifornia
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Ambiguity A word or sentence is ambiguous when it has more than
one sense.- A sentence is ambiguous if it has two (or more)
paraphrases which are not themselves paraphrases ofeach other.
e.g. We saw her duck
i) We saw the duckbelonging to her.
ii)We saw her lower her head. (i and ii are notparaphrases)The chicken is ready to eat(ambiguous)
Visiting relatives can be boring
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A word or phrase is ambiguous if it has two (ormore) synonyms that are not themselvessynonyms of each other
trunk - I) elephants proboscis
ii) chest
(i/ii are not synonyms of each other, therefore,trunk is ambiguous)
there are two classes of ambiguous words(homonymy and polysemy)
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A. homonymy
Homonyms are different words that are pronounced the same,but may or may not be spelled the same.
The different senses of the word are far apart from eachother and not obviously related to each other in any way(accidentally converge on the same form/pronunciation)
e.g. tale-tail
to-too-two
bear-bear-bare (V-N-A)
mug ( drinking vessel vs. gullible person)
bark (of a dog vs. of a tree)steer (to guide vs. young bull)
pole (stick vs. Norht pole)
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B.polysemy
when a word has several very closely related
sensese.g. mouth (of a river vs. of an animal)
ceiling (top inner surface vs. upper limit)
earth (our planet/soil)
tail (of a coat vs. of an animal)
bear (tolerate vs. carry)
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cf. homograph: different words spelledidentically and possibly pronounced the same
(in which case, they become homonyms)e.g.
bear (V vs. N) homographs and homonyms
pen (for writing vs. cage) homographs andhomonyms
but,
lead (verb vs. noun) homographs, but nothomonyms
tail vs. tale not homographs, but homonyms
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heteronyms: homographs that are pronounceddifferently (like lead)
bow, wind, lead, dove (N. vs. V-past)
Homonym homograph heteronym
Pronounced
identically
yes maybe no
Spelled
identically
maybe yes yes
li ti b t bi d d
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generalization about ambiguous words andsentences
Not all sentences which contain ambiguous words are
ambiguous. Also there are sentences which areambiguous even though they dont contain anyambiguous words.
e.g. kind (generous vs. class/sort)A kind young man helped me to cross the road.
A pike is a kind of fish.
John went to the bank (to deposit the money).
The captain corrected the list.
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lexical ambiguity vs. structural ambiguity
lexical ambiguity : an ambiguity resulting from
the ambiguity of a wordstructural ambiguity : an ambiguity resulting
from different relationship among the words
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Principle of compositionality
Principle of compositionality
The meaning of an expression is composed of
the meanings of its parts and how they are
combined structurally.
In other words, the meaning of a linguistic
expression is built both on the words it
contains and its syntactic structure.
l f
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Semantic Rules for meaningcomputation (P. 179)
What is the meaning of the sentenceJack swims?
The meaning of a sentence is its truth value and if we
know the meaning of a sentence, we know when it is true
or false.
Semantic Rule I
If the meaning of NP (an individual) is a member of themeaning of VP (a set of individuals), then S is TRUE;
otherwise it is FALSE.
i l f i
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Semantic rules for meaningcomputation (2)
What is the meaning ofJack kissed Laura?
Semantic Rule II.
The meaning of [ V NP] is the set of individuals
such that X is the first member of any pair in themeaning of V whose second member is the
meaning of NP.
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When compositionality go awry(P181)
1. Anomaly (meaningless words, or wrong combination)
Colorless green ideas sleep furiously
a table ago; Twas brillig, and the slity toves
2. Metaphor (requires a lot of creativity and imagination)
Our doubts are traitors; Walls have ears
Time is money;
3. Idioms (fixed meanings, no compositionality)
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Evidence for semantic features
Semantic properties are not directly observable butthey can be inferred from linguistic evidence.
1)From speech errors, or slips of the tongue
bridge of the nose -> bridge of the neckhe came too late -> he came too early
Mary was young -> Mary was early
The incorrectly substituted words are not randomsubstitutions but share some semantic feature
with the intended words
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Evidence for semantic features (2)
2) We can group the words on the basis of
semantic properties (See p.194)
doctor dean professor teenager
bachelor parent baby child