Syntax and Grammar

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Syntax and Grammar

• John Goldsmith
• Cognitive Neuroscience
• May 1999

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Two views of language to avoid like the
plagueThought is like language, and language
thought.
Thoughts
If your thoughts are clear enough, they will
naturally coalesce into words (and in the right
order).
Its not so much that these ideas are wrong as
they are pernicious. They lead to fuzzy and
uncontrollably bad thinking.
The cat is on the mat
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Language is a Markov process

• Given the last three words, we should be able to
  predict the next word with very high accuracy.

I
came
upon
As I turned ...
round
the
corner
Whats the first word on the next slide?
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Syntax

• The study of how words are assembled in
  meaningful, grammatical utterances
• in particular languages.
• And generalizations across languages

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First, its lexical categories we care about, not
words.

• The bigger a pattern is, the more important it is
  to our study.
• Subjects precede their verbs in English is more
  important than
• the word after President Bill is Clinton.

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Categories?

• First, lexical categories
• What is the best set of categories we can find to
  specify what sentences are grammatical in English
  ()

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• If we know that
• the cat is on the mat
• is grammatical in English, how does this extend
  as a generalization? Can we replace cat by other
  words and still get a good sentence? Of course.
  By what words? Is it, say, by any word starting
  with c? No.

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The cat is on the mat

• We have a category (we call them nouns) in
  English our best approximation to how one
  sentence can be matched to an indefinitely large
  pattern is by replacing a word by any other word
  in the same category.
• The fish is on the platter.
• A bird is over a tree.

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How many such categories are there?

• The most honest answer would be
• thats a matter of analytical convenience.
• The more categories, the better we can make our
  predictions.
• If we allow ourselves just nouns, then well
  predict such monstrosities as
• The Robert is on the phone.
• The crying is up the hill.
• A inkling is through the milk.

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If we have more categories, we can make finer
distinctions and better predictions

• Proper nouns (Bill, Clinton, Monday), common
  nouns (bill, sound, trophy), pronouns (me, I,
  she, it, we).
• They share some properties, but differ in a lot
  of ways at the same time.

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Lets focus on common nouns for a while.

• What makes a common noun in English?
• Often preceded by the or a.
• Often preceded by a possessive (my, your, his,
  her, our) or a demonstrative (this, that, these,
  those).
• An adjective may intervene, though
• this old house, my first car, first my car
• (but At first my car ran well)

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Summarizing

• By and large (almost always), if a word may be
  preceded by the, it may be preceded by a/an, or
  by my, your, his, her.
• We want a compact manner of representing this.

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A compact manner? Why?

• 1. Compact manner of remembering your experience
  thats the best your memory can do it extracts
  what is hopefully significant, because it cant
  memorize all.
• 2. Compact manner of describing is the test of
  scientific success (Minimal Description Length/
  Jorma Rissanen Ray Solomonoff).
• 3...

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• Lasnik (283) Given the creative use of
  languagesit could not be true that the syntax of
  a language consisted merely of a list of
  sentences that are memorized in the course of
  language acquisition. Something more complex,
  hence, more interesting, must be involved.

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Categories and phrase-structure rules

• Writing all generalizations in terms of
  categories (not lexical items words) is a way
  of compressing descriptions. Notice that it
  always makes wrong predictions! (Why? examples?)
• There is thus a trade-off between compact
  description prediction and accuracy.

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Categories and Phrase-structure rules

• Phrase structure rules are excellent means of
  expressing the idea that two categories often
  appear in adjacent positions
• C -gt A B
• NP-gtarticle noun
• Theyre also good for saying that something may
  optionally appear in between
• C-gt A (X) B

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Phrase-structure rules in English

• S ? NP VP
• NP ? det (Adj) Noun
• VP ? Verb (NP) (PP) (S)
• PP ? Prep Noun

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Phrase-structure rules

• Express generalizations about the fine internal
  structure around phrasal heads (nouns, verbs,
  adjectives)
• Head-argument structures verbs take NP ( Noun
  Phrase) complements (which can be large chunks)
• But...

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S
What did Linda say S
Monica had told her D
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Coreference properties

• Pronouns almost always follow the noun they refer
  to
• John is going to California, and hes very
  excited about that. (try it the other way around)
• Before John studied linguistics, he said a lot of
  stupid things about language.

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• Before he studied linguistics, John said a lot of
  stupid things about language.
• So both orders are OK there. Worse yet
• In front of him, John saw a snake.
• In front of John, he saw a snake.

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Main claim that appears to come from looking at
language asphrase structure

• The big picture, the main facts about the syntax
  of a language are expressed by phrase-structure
  rules, which use categories.
• To know where a certain phrase may appear, you
  only need to know its category, not whats
  inside it.

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You dont need to know whats inside it?

• That is true in mathematical and logical
  formulas

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But its not true in language.

• Its only a useful first approximation.
• Q Are there self-standing sentences that cant
  be embedded?
• A You bet.
• Like father, like son.
• Fathers who like, like son get along well with
  their kids.

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• Can nouns select certain kinds of determiners?
  Certainly
• A vast expanse of linguistics is devoted to
  exploring and accounting for the complexities
  that transcend phrase-structure rules.

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Syntactic Structure

• Sign on the highway in Oklahoma (really)

Hitchhikers may be escaping convicts.
So? Pick them up? Dont pick them up?
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Sentence Aux phrase
Aux
Aux
verb phrase
Noun phrase
Verb
Noun
Noun
Adjective
Hitchhikers may be escaping convicts.
Copula semantically main verb
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Sentence Aux phrase
Aux
Aux
verb phrase
verb phrase
Verb
Noun
Verb
Noun
Hitchhikers may be escaping convicts.
Main verb
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Syntactic structure

• What did the Buddha say to the hot-dog vendor?

Make me one with everything.
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BE
Make me rich and famous and in tune with the
universe
Make me one with everything.
Make a hot-dog with everything on it for me,
please
have
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• What did the vendor say when the Buddha asked him
  for his change from the 20?

Change must come from within.