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CAS LX 522 Syntax I Class 1a. Introduction to the enterprise Some things we know Is this English? The cat slept. Slept the cat. Cat slept the. Cat the slept. – PowerPoint PPT presentation

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Title: Class 1a. Introduction to the enterprise


1
CAS LX 522Syntax I
  • Class 1a.Introduction to the enterprise

2
Some things we know
  • Is this English?
  • The cat slept.
  • Slept the cat.
  • Cat slept the.
  • Cat the slept.
  • Why?

3
The task
  • What do we know?
  • The comes before cat, cat comes before slept.
  • Try to generalize.
  • Slept is the verb, maybe this holds of all verbs.
  • The cat is the subject, maybe this holds of all
    subjects.
  • Subjects contain the and a noun, with the first.
  • An English sentence has a subject followed by a
    verb.
  • Formalize (make precise)
  • Nouns cat, dog
  • Verbs slept, yawned
  • Sentence Subject the Noun Verb

4
The task
  • Check
  • Sentence Subject the Noun Verb
  • The cat slept.
  • The dog yawned.
  • The cat yawned.
  • The dog slept.
  • Look at further data (predictions)
  • The cat chased the dog.
  • This is an English sentence, but our schema
    cannot produce it. Our theory of English
    sentences is insufficient. We need to
    revise/extend it.

5
The task
  • Consider the counterexample (or the class of
    counterexamples) to understand where the current
    theory falls short.
  • The cat chased the dog.
  • The dog is probably the same kind of thing as the
    cat, but we dont want to call it a subject
    (its traditionally called the object).
  • It contains the and a noun, and the noun seems to
    be the most important part.
  • Since it contains more than one word, we can call
    it a phraseits not a whole sentence, but its
    more than a word.
  • So, well call it a noun phrase.

6
The task
  • Consider the counterexample (or the class of
    counterexamples) to understand where the current
    theory falls short.
  • The cat chased the dog.
  • In this English sentence, there is a noun phrase
    both before and after the verb. So, in addition
    to our previous schema, we add a second one.
  • Theory of English sentences
  • Sentence NP the Noun Verb
  • Sentence NP the Noun Verb NP the Noun

7
Lather, rinse, repeat
  • And the process continues.
  • The cat chased a dog.
  • A cat chased the dog.
  • A cat chased a dog.
  • It looks like a NP can either have the or a as
    its first element. Thus
  • Theory of English sentences
  • Sentence NP the Noun Verb
  • Sentence NP a Noun Verb
  • Sentence NP the Noun Verb NP the Noun
  • Sentence NP the Noun Verb NP a Noun
  • Sentence NP a Noun Verb NP the Noun
  • Sentence NP the Noun Verb NP a Noun

8
Generalizing
  • What weve ended up with is a bit clumsy, but we
    can now generalize our schemas to make this more
    compact
  • NP the Noun
  • NP a Noun
  • Sentence NP Verb
  • Sentence NP Verb NP
  • Not only does this reduce the amount we have to
    write down, but it actually makes a more profound
    prediction If this much of our theory of English
    sentences is right, then anything that can be a
    noun phrase subject can also be a noun phrase
    object. This is not just making our notation more
    compact, but it is a substantive addition to the
    theory.

9
Compacting the notation
  • There are some further ways we can consolidate
    our theory of English sentences by using some
    common notational tools.
  • X is optional (X)
  • Either Y or Z Y/Z
  • Thus
  • Sentence NP Verb (NP)
  • NP the/a Noun
  • Unlike our introduction of a separate schema for
    NP, this change is not a substantive change to
    our theory of English sentences, it is just a
    shorthand for the same theory.

10
The grumpy cat
  • As a demonstration of the benefit of introducing
    a separate NP schema, consider
  • The grumpy cat chased the unhappy dog.
  • How can we extend our theory of English sentences
    to allow for this sentence? What other word
    sequences are predicted to be English sentences?
    Are they?

11
Now, what are we doing?
  • Ok, so we have the beginnings of a theory of
    English sentences. But what is it?
  • As weve developed it, it is a description of
    sentences of English, what we might need if we
    wanted to program a computer to produce English
    sentences.
  • But it is also a subset of what English speakers
    know about English.
  • You may or may not have previously thought about
    the fact that subjects precede verbs and objects
    follow verbs (or the analog in your native
    language), but you knew it nevertheless. You
    could identify sequences of words that did not
    have this property as not being part of your
    language, but its tacit knowledge. As such, we
    have to study this knowledge indirectly, based on
    what are judged to be valid sentences and what
    arent.

12
What English speakersknow about English
  • An English speaker has a complex system of
    knowledge that allows him/her to distinguish
    between sentences of English and non-sentences of
    English. Well refer to this system as a grammar.
    At its simplest, a grammar is a means of deciding
    whether a sequence of words is grammatical (e.g.,
    a sentence of English) or not. Were studying the
    properties of that system.
  • Its not always obvious what it is that is wrong
    with non-sentences, but still the judgments
    (intuitions) are clear.

13
Types of (un)acceptability
  • Big that under staple run the jump swim.
  • The dog are snoring.
  • These are ungrammaticalthere is a problem with
    their form, they are not English. We write to
    indicate this.
  • My toothbrush is pregnant again.
  • This is nonsensical, given our knowledge about
    the world (not about English), but it is
    grammatical.
  • As I knitted the sock The horse raced fell to
    the floor. past the barn fell.
  • The rat the cat the dog chased caught escaped
    adeptly.
  • These are interestingly difficult to parse but
    once you get it, they are fine (if clumsy)
    sentences of English.

14
Parentheses and optionality
  • In describing data, people will often use the (),
    shorthand notation to indicate optionality or
    options
  • Pat (quickly) ran to the bank.
  • Pat ran to the bank. Pat quickly ran to the
    bank.
  • Pat washed (quickly) the asparagus.
  • Pat washed the asparagus. Pat washed quickly the
    asparagus.
  • The dish ran away with (the) spoon.
  • The dish ran away with the spoon.
  • The dish ran away with spoon.
  • The cat chased a/the dog.
  • The cat chased a dog. The cat chased the dog.

15
Ambiguity and stars
  • Sentences can be ambiguous.
  • I sat by the bank.
  • Sometimes we might have reason to expect
    ambiguity that is not there, which is also
    indicated using , on a disambiguating
    continuation.
  • How did John say Mary fixed the car?
  • With a wrench.
  • In a high-pitched voice.
  • How did John ask if Mary fixed the car?
  • With a wrench.
  • In a high-pitched voice.

16
Knowledge of language is actually really
complicated
  • Bill told her mother that Mary is a genius.
  • Bill told her that Mary is a genius.
  • I told Mary that Pat gave a book to me.
  • Who did I tell that Pat gave a book to me?
  • Who did I tell Mary that gave a book to me?
  • Who did I tell Mary that Pat gave a book to?
  • I loaned Mary the book Pat gave me.
  • Who did I loan the book Pat gave me?
  • Who did I loan Mary the book gave me?
  • Who did I loan Mary the book Pat gave?

17
How do people know this?
  • All native speakers of English know this.
  • Little kids werent told these rules (or punished
    for violating them)
  • You cant question a subject in a complement
    embedded with that
  • You cant use a proper name as an object if the
    subject is co-referential.

18
Two questions
  • What do people know about their language?
  • Including things we know unconsciously
  • How do people come to know it?
  • Tricky question for things that we dont know we
    know.

19
Systematicity
  • What people eventually end up with is a system
    with which they can produce (and rate) sentences.
    A grammar.
  • Even if youve never heard these before, you know
    which one is English and which one isnt
  • Eight very lazy elephants drank brandy.
  • Eight elephants very lazy brandy drank,
  • Kids say wugs.

20
Positive and negative evidence
  • Adults know if a given sentence S is grammatical
    or ungrammatical. This is part of the knowledge
    kids gain through language acquisition.
  • Kids hear grammatical sentences(positive
    evidence)
  • Kids are not generally told which sentences are
    ungrammatical(no negative evidence)

21
Positive and negative evidence
  • One of the striking things about child language
    is how few errors they actually make.
  • For negative feedback to work, the kids have to
    make the errors (so that it can get the negative
    response).
  • But they dont make the errors.
  • (Kids do make errors, but not of the kind that
    one might expect if they were just trying to
    extract patterns from the language data they hear)

22
Poverty of the stimulus
  • What is the next number in this sequence?
  • 1, 2, 3, __
  • How do you form a yes-no question?
  • Pat will leave.
  • Will Pat leave?
  • The book that you were reading was good.
  • Book the that you were reading was good?
  • Were the book that you reading was good?
  • Was the book that you were reading good?

23
The Language instinct
  • The linguistic capacity is part of being human.
  • Like having two arms, ten fingers, a vision
    system, humans have a language faculty.
  • The language faculty (tightly) constrains what
    kinds of languages a child can learn.
  • Universal Grammar (UG).

24
But languages differ
  • English, French Subject Verb Object (SVO)
  • John ate an apple.
  • Pierre a mangé une pomme.
  • Japanese, Korean Subject Object Verb (SOV)
  • Taroo-wa ringo-o tabeta.
  • Chelswu-ka sakwa-lul mekessta.
  • Irish, Arabic (VSO), Malagasy (VOS),

25
But languages differ
  • English Adverbs before verbs
  • Mary quickly eats an apple.
  • (also Mary ate an apple quickly)
  • Mary eats quickly an apple.
  • French Adverbs after verbs
  • Geneviève mange rapidement une pomme.
  • Geneviève rapidement mange une pomme.

26
Parameters
  • We can categorize languages in terms of their
    word order SVO, SOV, VSO.
  • This is a parameter by which languages differ.
  • The dominant formal theory of first language
    acquisition holds that children have access to a
    set of parameters by which languages can differ
    acquisition is the process of setting those
    parameters.
  • What are the parameters?
  • What are the universal principles of grammar?

27
The enterprise
  • The data we will primarily be concerned with are
    native speaker intuitions.
  • Native speakers, faced with a sentence S, know
    whether the sentence S is part of their language
    or isnt. These intuitions are highly systematic.
  • We want to uncover the system (which is
    unconscious knowledge) behind the intuitions of
    native speakerstheir knowledge of language.

28
I-language
  • We are studying the system behind one persons
    pattern of intuitions.
  • Speakers growing up in the same community have
    very similar knowledge, but language is an
    individual thing (I-language).
  • One doesnt need to ask the académie française
    whether Geneviève rapidement mange une pomme is a
    sentence of French. One knows.
  • I-languages of a community is can be
    characterized, but it is external to the speaker
    (E-language), not any one persons knowledge, a
    generalization over many peoples I-languages.
  • For example, Parisian French.

29
Competence
  • We are also concerned with what a person
    knowswhat characterizes a persons language
    competence. We are in general not concerned here
    with how a person ends up using this knowledge
    (performance).
  • You still have your language competence when you
    are sleeping, in the absence of any performance.
    Being drunk doesnt make one think bought some
    John coffee is English, though perhaps one might
    say it.

30
Prescriptive rules
  • Another thing we need to be cautious of are
    prescriptive rules. Often prescriptive rules of
    good grammar turn out to be impositions on our
    native grammar which run counter to our native
    competence.
  • After all, why did they need to be rules in the
    first place?

31
Prescriptive rules
  • Prepositions are things you dont end a sentence
    with.
  • It is important to religiously avoid splitting
    infinitives.
  • Remember Capitalize the first word after a
    colon.
  • Dont be so immodest as to say I and John left
    say John and I left instead.
  • Impact is not a verb.
  • The book which you just bought is offensive.

32
Prescriptive rules
  • When making grammaticality judgments (or when
    asking others to make grammaticality judgments),
    we must do our best to factor out prescriptive
    rules (learned explicitly, e.g., in school).
  • Were not interested in studying the prescriptive
    rules we could just look them up, and it isnt
    likely to tell us anything deep about the makeup
    of the human mind. Theyre really just a secret
    handshake, allowing educated people to detect
    one another.

33
Syntax as science
  • Syntax, as practiced here, is a scientific
    enterprise. This means, in particular,
    approaching syntax using the scientific method.
  • Step 1 Gather observations (data)
  • Step 2 Make generalizations
  • Step 3 Form hypotheses
  • Step 4 Test predictions made by these
    hypotheses, returning to step 1.

34
Syntax as science
  • This is pretty much the way other scientific
    disciplines work biology, chemistry, physics.
  • We may start out with a kind of folk
    understanding of a field.
  • For example, you push something and it moves. You
    stop pushing, and it stops. The sun revolves
    around the earth from East to West, followed by
    the moon. Water is a basic element, like fire.
    Whales are very big fish, like dolphins, or tuna,
    but bigger.
  • Ockhams Razor posit as few concepts and
    relations as we can get away with. A leaner
    theory is a better theory. A more easily
    falsifiable theory is a better theory too.

35
Levels of adequacy
  • If our hypotheses can predict the existence of
    the grammatical sentences in a corpus (a set of
    grammatical sentences), it is observationally
    adequate.
  • Note the grammar described by some number of
    words appear in some order is observationally
    adequate, for pretty much any language. This is
    not a very difficult or satisfying level of
    adequacy to reach. Nor is it disprovable, but it
    hasnt really advanced our understanding of the
    world.
  • If our hypotheses can predict the native-speaker
    intuitions about which sentences are grammatical
    and which are ungrammatical, it is descriptively
    adequate.

36
Levels of adequacy
  • If we can take a descriptively adequate set of
    hypotheses one step further and account not only
    for the native speaker judgments but also for how
    children come to have these judgments, our
    hypotheses are explanatorily adequate.
  • Its this last level that we are hoping to
    achieve.
  • Basic principles
  • Parameters of variation
  • How to set the parameters from childs input

37
Infinite use of finite means
  • English has an infinite number of sentences. Any
    natural language does.
  • John said that English has an infinite number of
    sentences.
  • Mary said that John said that English has an
    infinite number of sentences.
  • Pat said that Mary said that John said that
    English has an infinite number of sentences.
  • Tracy said that Pat said that Mary said that John
    said that English has an infinite number of
    sentences.
  • Chris said that Tracy said that Pat said that
    Mary said that John said that English has an
    infinite number of sentences.
  • If S is a sentence and N is a name,N said that S
    is also a sentence.
  • S ? N said that S
  • Some of the earliest work in grammatical theory
    was done by trying to state rules of this form,
    the goal being to generate the sentences of a
    language.

38
Of the past and the future
  • Serious scientific study of sentence structure of
    this kind generally began in the 50s, driven to
    a large extent by the work of Noam Chomsky.
  • Its now half a century later, and we have
    learned a lot about how syntax works.

39
Of the past and the future
  • Progress was incremental, and often required
    revising our assumptions about how sentences are
    really put together.
  • Data was examined, generalizations were arrived
    at, hypotheses were formed, predictions were
    testedand often led to revisions of the
    generalizations and the hypotheses, and so forth.

40
Of the past and the future
  • Two goals of the class
  • Think like a syntactician.
  • Be able to read (relatively recent) books,
    articles, etc. about syntax.
  • Its not really enough to just know what people
    concluded, we need to understand why they
    concluded what they did.

41
Some milestones
  • Until about the mid-70s, phrase structure rules.
  • S ? NP VP VP ? V (NP)
  • Mid-70s, X-Bar Theory (a generalization about
    what are possible PSRs).
  • In the 80s, a fairly significant shift to
    Government and Binding Theory (viewing grammar a
    little less like a computer program). Very
    productive.
  • In the 90s, another shift to the Minimalist
    Program (an attempt at simplification, as well as
    a change in philosophy).

42
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