CAS LX 502

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CAS LX 502

• 6b. Context and inference
• 7.4-

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Context and meaning

• Nearly everything one reads or hears requires
  knowledge of context to interpret.
• This can include
• Physical context
• I dont know why they did it.
• Prior conversation
• And then he just up and left.
• Me too.
• Background/common knowledge
• The President has resumed eating pretzels.

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Background knowledge

• Generally assumed real-word/cultural knowledge,
  common ground, presuppositions of discourse.
• Probably not actually mutual knowledge (that is,
  propositions that are both known to the
  interlocutors and known to be known to both.
• Shall we go get some ice cream?
• Im on a diet.
• Fine, a protein shake then?

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Inference

• A lot of communication actually takes the form of
  inference, conclusions drawn from things unsaid.
  Assuming connections between sentences.
• I walked into the room. The windows looked out
  onto the bay.
• We know things about rooms. They have windows,
  often.

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Schank and Frames

• No discussion of our reliance on background
  knowledge can avoid mentioning Roger Schanks
  work almost 30 years ago trying to teach
  computers semantics.
• Schank et al. devised scripts to represent common
  situations, to form a backdrop for a
  conversation. The standard example is the
  restaurant script

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Restaurants

• Actor goes to a restaurant
• Actor is seated
• Actor orders a meal from waiter.
• Waiter brings meal to the actor
• Actor eats the meal
• Actor gives money to the restaurant
• Actor leaves the restaurant.
• John went to a restaurant. The waiter gave John a
  menu. The waiter came to the table. John ordered
  a lobster. John was served quickly. John left a
  large tip.
• What did John eat? (Lobster)
• Who gave John the menu? (Waiter)
• Who gave John the lobster? (Probably waiter)

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Information packaging

• Information in utterances is generally packaged
  in a way that can take advantage of the
  background knowledge and inferences available.
  Information structure.
• One way this is accomplished by presuppositional
  items like the or stop, taking something in the
  context to be given.

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Given vs. new

• Much of what falls under information structure is
  the division of given and new.
• In the domain of noun phrases, for example, the
  indefinite article a(n) is used to introduce a
  new referent, which can thereafter be referred to
  as given (with the).
• A man walked into the room. The man carefully
  hung up his coat and sat down.
• Sometimes this is modeled by analogy to file
  cards. A man creates a file card (a place to hold
  information about an individual referent), and
  then the man refers back to that file card.

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Pronouns

• Pronouns refer exclusively to given information
  (although their reference can come from the
  physical context via pointing).
• Anaphora, indirect reference relation.
• John ate a sandwich. He felt satisfied.
• Note When working with syntax, anaphora are
  generally divided into two kinds (that have
  distinct conditions) anaphors (himself, herself,
  ), and (anaphoric) pronouns (him, her, ).
• Mary saw her. Mary saw her reflection. Mary saw
  herself.

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Focus and given/new

• Another way that information is marked as being
  new is through the use of focus (dividing the
  sentence into the focus and the presupposition,
  or the new and the given)
• HENRY cleaned the kitchen.Someone cleaned the
  kitchen.(It was) Henry.
• Henry CLEANED the kitchen.Henry did something to
  the kitchen.(It was) cleaning.

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Contrast

• Focus generally induces a kind of contrast.
• What did you get for your birthday?
• I got a CHEESE GRATER.
• I thought John opposed that bill.
• What? No, he VOTED for it.
• Many languages mark focus morphologically, with a
  focus marking particle. English tends to use
  stress, or clefts, pseudo-clefts like
• It was a cheese grater that I got.
• What I got was a cheese grater.

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Topic

• Often there is a sentence topic (separate from
  discourse topic). These too are often
  morphologically marked (Japanese wa), in English
  it can be paraphrased with As for.
• As for birthday gifts, I got a cheese grater.
• Me, I cant figure him out.
• Topics are either given information or introduced
  as if they were.
• This guy, he asked me for directions.
• As for him, he couldnt care less.

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On file cards

• A woman with a small child came in
• Shewa ordered chicken-fried steak.
• Next, a young man holding a tennis racket came
  in.
• Hewa handed her the racket and went to the bar
  to get a beer.
• Another man and woman, who were late, came in.
• It seemed (they) had been at a movie. (Portner
  and Yabushita 1998)
• The woman who ordered chicken-fried steak left
  first.
• ??The woman who the man had handed a racket to
  left first.

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Focus and questions

• John did not introduce Bill to SUE.
• John did not introduce BILL to Sue.
• Evoked questions
• Where were you at the time of the crime?
• I was at HOME.
• I was at HOME.
• Evoked questions, a superquestion, and a strategy.

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Conversational implicature

• Paul Grice Inferences can be predicted by
  adopting a cooperative principle.
• The idea is that we can draw conclusions based on
  what is said in addition to making the assumption
  that the speaker is participating cooperatively.
• How is Charles getting on in his job?
• Oh quite well, I think. He likes his colleagues,
  and he hasnt been to prison yet.
• Grice identified several aspects of this
  cooperation, which he called maxims.

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Gricean maxims

• Quality Be truthful.
• Do not say what you believe is false.
• Do not say that for which you lack adequate
  evidence.
• Quantity Be informative.
• Make your contribution as informative as
  required.
• Do not make your contribution more informative
  than required.
• Relation Be relevant.
• Make your contribution relevant.
• Manner Be perspicuous.
• Avoid ambiguity, obscurity.
• Be brief, orderly

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Conversational implicatures

• Pat has two children.
• Im out of gas. Theres a garage around the
  corner.
• Im out of gas. Theres a tiger eating my
  lunch.
• The dinner was adequate. (In fact, it was great.)
• Mr. Smith always shows up to class on time and
  well-dressed.
• Ms. Smith produced a series of sounds that
  corresponded closely with the score of Home Sweet
  Home.
• Bill is a fine friend.

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Entailment and informativeness

• I have a red sock ? I have a sock
• I have one sock ? I have two socks ?I have three
  socks ? I have four socks
• I have four socks is a stronger statement than I
  have one sock.

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Focus sensitive adverbs

• John did not give a book to MARY.
• John even gave a book to MARY.
• John only gave a book to MARY.
• Informativeness
• John has a book.
• John has two books.
• John has twelve books.

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NPIs

• I dont have any socks.
• I have any socks.
• Do you have any socks?
• If I had any socks, I wouldnt be calling you.
• Any socks would be welcome.
• Pick any card.
• Every student with any socks is happy.
• Every happy student has any socks.

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Entailment

• I have a red sock ? I have a sock.
• I dont have a red sock ? I dont have a sock
• If I had a red sock, I wouldnt be calling you
  ?If I had a sock, I wouldnt be calling you
• A red sock would be welcome ?A sock would be
  welcome
• Pick a red sock ? Pick a sock
• Every student with a red sock is happy ?Every
  student with a sock is happy.
• I dont have any socks. If I had any socks, I
  wouldnt be calling you. Any sock would be
  welcome. Pick any sock.

socks
red socks
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NPIs

• Do you have dry socks?I dont have any
  socks. Downward entailing
• Do you have potatoes?Nope.Not even bruised
  ones?I dont have any potatoes. Leave me alone.
• I dont have even one sock. DE, stronger.
• I have even one sock. UE, not stronger.

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