Transcript Document

Semantics, part 2
April 13, 2009
The Last Details
• For starters: a word association Quick Write.
• Semantics/pragmatics homework is due on Wednesday.
• any questions?
• We’re still working on grading the syntax homework;
• You will (hopefully) have it back by Wednesday.
• Future plans:
• Wednesday - wrap up semantics
• Friday - review session (for whoever wants one)
• Also: office hours from 12 to 1 tomorrow.
Compositional Recap
•
Last time, I introduced the correspondence theory of
truth:
1. Propositions can be true or false.
2. Truth is the correspondence of propositions to facts.
•
A valid objection: subjective vs. objective truth.
•
Subjective: “It’s warm outside.”
•
Objective “fact”: “The Red Wings won the Stanley Cup
last year.”
•
Possible fix: subjective truths may be true from only
one person’s perspective;
•
Objective truths are true from all possible
perspectives.
Sapir-Whorf Hypothesis
• In the early twentieth century, the linguists Edward Sapir
and Benjamin Whorf proposed the following (controversial)
hypothesis:
• A person’s conception of reality is dependent upon the
language they speak.
• Edward Sapir (1929):
“Human beings do not live in the objective world alone,
nor in the world of social activity as ordinarily understood,
but are very much at the mercy of the particular language
which has become the medium of expression for their
society…we see and hear and otherwise experience very
largely as we do because the language habits of our
community predispose certain choices of interpretation.”
Sapir-Whorf Hypothesis
• Benjamin Whorf (1956):
“The background linguistic system (in other words, the
grammar) of each language is not merely the reproducing
instrument for voicing ideas but rather is itself the shaper
of ideas, the program and guide for the individual’s
mental activity, for his analysis of impressions, for his
synthesis of his mental stock in trade…We dissect nature
along lines laid down by our native languages.”
• Intriguing thoughts, but…
• Hard to prove in reality.
• One interesting piece of evidence:
• Differences in the way that languages organize the
color spectrum.
Reference: Basic Color Terms
purple
blue
green
yellow orange
red
Color names for the spectrum of light in English
Note:
Hungarian distinguishes between piros “light red” and voros
“dark red“
Russian distinguishes between sinij “dark blue” and goluboj
“light blue”
Reference: Color Terms
cipswuka citema
cicena
cipswuka
Color names for the spectrum of light in Shona
(spoken in Zimbabwe)
Note: cipswuka applies to “orange”, “red” and “purple”
Reference: Color Terms
hui
ziza
Color names for the spectrum of light in Bassa
(spoken in the Ivory Coast)
Patterns of Color Terms
• Brent Berlin and Paul Kay (1969) catalogued the color
terms of 98 different languages.
• They presented speakers of a language with an array of
329 color chips.
• Task:
• for each color word in that language, circle all the
chips that it applies to
• Also: circle the chip that is the best example of that
color
Color Matching Results
• Every language has at least two basic color terms
• basically: dark (“black”) and light (“white”)
• Bassa is a two-color language
• Languages with three color terms add red
• Languages with four color terms add green or yellow
• Fifth color term: either green or yellow
• Sixth color term: blue
• Seventh color term: brown
• The rest: purple, pink, orange or gray
Big Picture
• Different languages divvy up the color spectrum in
different ways;
• but there are still language-universal patterns in the
types of color schemes available to languages.
• As linguists, we want to know what competent speakers
of a language need to know in order to produce
meaningful utterances in that language.
• = the semantic features of a language
• There are language-specific and language-universal
semantic features.
• As in syntax, whatever is language-universal may be
attributed to our innate mental endowment for both
language and thought.
Moving On
•
There are several different ways to study meaning in
language:
1. Pragmatics
The meaningful use of linguistic expressions in
conversation and discourse.
2. Compositional Semantics
How the meaning of phrases and sentences is built up
from the meanings of individual words.
3. Lexical Semantics
The meaning of individual words, and how they’re
related to one another.
Lexical Semantics
•
Here are two basic meaning relationships that words
can have with one another:
1. Synonymy
•
Two words have the same meaning
•
couch/sofa, groundhog/woodchuck, hide/conceal
•
= real-world extensions are identical
2. Hyponymy
•
one word’s extension is a subset of another word’s
extension
•
poodle/dog, laptop/computer, gas giants/planets
Synonym Schematic
Fido
Marmaduke
Garfield
Rex
Spot
Snoopy
Fifi
Mr. Meowser
Tinkerbell
The Death Star
Lassie
is a dog
is a canine
canines and dogs are
synonyms
Hyponym Schematic
Fido
Marmaduke
Garfield
Rex
Spot
Snoopy
Fifi
Mr. Meowser
Tinkerbell
The Death Star
Lassie
dogs
poodles
poodle is a hyponym
(subset) of dog
Another One
• Antonymy: when words that mean the “opposite” of each
other
• Complementary antonyms:
• Everything in the world is one or the other
• unmarried/married, present/absent, visible/invisible
• Relational antonyms:
• Reflect a symmetrical connection between each other
• give/receive, buy/sell, teacher/pupil
• employer/employee, adviser/advisee
• Scalar antonyms: words form two ends of a scale
• hot/cold, happy/sad, big/small, fast/slow
Homonyms/Homophones
• Homonyms/Homophones are words with:
• same pronunciation
• unrelated meanings
• from Greek: /homo-/ “same” + /onyma/ “name”
• Examples:
• trunk (of an elephant), trunk (chest), trunk (of a tree)
• also: bear, bare
• Homonyms can create ambiguity:
• We saw her duck.
Polysemy
• Polysemy is when one word has several different, but
related meanings.
• From Greek: /poly-/ “many” + /sema/ “signal”
• Examples:
• Mouth of a river ~ mouth of an animal
• A baseball diamond ~ a geometric diamond ~ a
diamond stone
Intersection
• Compositional semantics, continued...
• We have discussed how the referents of nouns and
the extensions of predicates get put together to form a
meaningful proposition.
• Now let’s consider adjectives and nouns in noun phrases.
• Simplest case: pure intersection
• black dogs =
• the set of all dogs
intersected with
• the set of all black things
Pure Intersection Schematic
Marmaduke
Odie
Lassie
Charcoal
Spot
Rex
Darth Vader
Spuds
Oil
dogs
black
dogs
black things
Pure Intersection of Music
Snobbery
Semantic Features
• Idea: the meaning of a word can be precisely determined
by the pure intersection of predicates of which it is a
hyponym (subset).
• Example: “square”
[TWO-DIMENSIONAL, FOUR-SIDED, EQUAL-SIDED]
• Example: “bachelor”
[HUMAN, MALE, UNMARRIED]
• The predicate sets form a word’s semantic features
• “hen” and “mare” share the feature [FEMALE]
• “bachelor” and “woman” share the feature [HUMAN]
Verb Features
• The same semantic feature can be expressed by a variety
of different verbs.
• Example: the feature [GO]
• reflects a change in position
• fly, walk, roll, stumble, run, crawl, etc.
• More subtle examples of [GO]:
• give: “John gave Mary an engagement ring.”
John
Mary
ring
• “The boy threw the ball over the fence.”
A Syntax Flashback
• Remember that, in syntax, we learned that different verbs
require specific complement structures.
• For instance, transitive verbs require an object NP in
their verb phrases.
I devoured the sandwich.
I met the Professor.
• Similarly, ditransitive verbs require two objects in their
verb phrases.
The dog trainer sold me a chew toy.
Larry gave Shelly the textbook.
Syntax/Semantics
• There are sub-features of [GO], which are reflected in
constraints on verb complements in English.
• [BALLISTIC]: a one-time [GO]
V’  V NP NP
• [SUSTAINED]: a continuous [GO]
*V’  V NP NP
• Ballistic Verbs
Sustained Verbs
throw the boy a ball
*push the boy a ball
toss the boy a ball
*pull the boy a ball
kick the boy a ball
*lift the boy a ball
fling the boy a ball
*drag the boy a ball
Role-playing
• The objects of ditransitive verbs can be expressed in two
different syntactic ways:
Larry gave Shelly the textbook.
(NP NP)
Larry gave the textbook to Shelly.
(NP PP)
• Despite the syntactic differences, each noun plays the same
role in both sentences:
Larry: Agent
(the entity performing the action)
Textbook: Theme
(thing being acted upon)
Shelly: Recipient
(being coming into possession
of something)
Thematic Roles
• Verbs have semantic requirements.
• For a sentence to make sense, it has to include nouns
which can play the roles required by the verb.
• give: Agent; Theme; Recipient
Larry gave Shelly the textbook.
Larry gave the textbook to Shelly.
Shelly was given the textbook by Larry.
!Anger gave Shelly the textbook.
Other Thematic Roles
• Experiencer
• = animate being that has a perceptual or mental
experience.
• Ex: Susan heard the music.
• Source
• = the origin of a change.
• Ex: Jan arrived from Detroit.
• Instrument
• = the means used to accomplish an action (not agent)
• Ex: The hammer cracked the window.
Other Thematic Roles
• Goal
• = the end point of a change in location or possession.
• Ex: Chris hitchhiked to Alaska.
• Location
• = the place where an action occurs.
• Ex: Neil Young played a show in Winnipeg.
Cross-language Data
• Consider the sentence: I like the book.
“I” is the experiencer in this sentence.
It is also the subject of the sentence.
• Other languages express this notion with different syntax:
German: Das Buch gefällt mir.
French: Le livre me plaît.
Spanish: El libro me gusta.
• In all of these languages, the speaker is the semantic
experiencer of “liking” the book...
• But is the syntactic object of the sentence.
By the way
• Particular verbs can have highly specific thematic
restrictions.
• E.g.: the Experiencer of “sleep” has to be animate.
!Colorless green ideas sleep furiously.
• The object of “frighten” has to have a mind.
Sincerity may frighten the boy.
!The boy may frighten sincerity.
• Other examples:
Time elapsed.
!John elapsed.
It is snowing.
!The dog is snowing.
Verb Features
• Another verb feature: [CAUSE]
• Contrast:
The water boiled.
Laura boiled the water.
The door opened.
The wind opened the door.
The window broke.
Larry broke the window.
• When these verbs are transitive, they have this
semantic structure:
X CAUSED Y to Z
Laura CAUSED the water to boil.
Causatives
• In some languages, the [CAUSE] feature is realized
morphologically.
• Songhay (spoken in Burkina Faso):
Feneter
di
ba.
window
the
broke
“The window broke.”
Ali
ba
ndi
feneter
di.
Ali
broke [CAUSE]
window
the
“Ali broke the window.”