Empty category phenomena in LFG

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Empty category phenomena in LFG

• Nigel Vincent
• University of Manchester

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Caveat

• This presentation was prepared for use at the
  LFG Winter School held at the University of
  Canterbury, 4-8 July 2004. It was designed to
  follow on from the foregoing presentation by
  Kersti Börjars. Feel free to make use of it but
  please acknowledge the source.

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Properties of LFG

• Non-derivational
• Parallel correspondence
• Monotonic

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Therefore LFG eschews

• movement
• the (consequent) use of empty categories
• the (consequent) use of uninterpretable features
• (in particular Case and EPP)
• Instead, new analytical tools consistent with
  LFG premisses need to be found

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A typology of empty categories
Construction Empty category Overt category
Finite clause arguments pro pronouns
Non-finite clause, equi subjects PRO
Raising/passive NP/DP trace anaphors (herself)
Unbounded dependencies wh-trace R expressions
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The treatment of pro-drop

• Italian (Memo) canta

canta
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f-structure for canta (s)he sings
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English non-pro-drop

• English Bill sings vs sings

sings
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Control and raising

• Missing subject relatable to matrix verb
• Missing subject is a semantic argument of both
  verbs control (aka equi)
• e.g. Bill tried to dance
• missing subject only a semantic argument of the
  infinitival verb raising
• e.g. Bill seemed to dance

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equi vs raising

• Equi traditionally handled via a construction
  specific empty category with no overt analogue,
  viz PRO
• Bill tried PRO to dance
• Raising handled via movement
• e seemed Bill to dance

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Obligatory (OC) vs non-obligatory (NOC) control
OC antecedents NOC antecedents
obligatory optional
local non-local
c-commanding not c-commanding
unique split
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Bill tried to dance

• to dance requires a verb to introduce it
• introducing verb is in the next clause up
• therefore introducing verb c-commands inf.
• no split antecedence, so
• Bill tried (for him and Sally) to dance

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f-control OC

• Let us first observe that Williams obligatory
  control corresponds to our functional control.
  That is, the central properties that Williams
  takes to be characteristic of obligatory control
  follow from our theory of functional control.
• (Bresnan 1982 350)

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Functional control

• Involves structure sharing between SUBJ of
  matrix verb and SUBJ of embedded verb
• Structure sharing achieved by means of a new type
  of function, namely the open function XCOMP

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COMP vs XCOMP

• COMP
• Bill said that Sally appointed Sue
• COMP
• XCOMP
• Bill persuaded Sally to appoint Sue
• OBJ XCOMP

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Lex entries say, try, persuade

• say say lt(SUBJ) (COMP)gt
• try try lt(SUBJ) (XCOMP)gt
• persuade
• persuade lt(SUBJ) (OBJ) (XCOMP)

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Lexical Rule of f-control

• For any lexical form
• a) XCOMP SUBJ OBJ if present
• otherwise
• b) XCOMP SUBJ SUBJ

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F-structure for try
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try try lt(SUBJ), (XCOMP)gt(XCOMP SUBJ) (SUBJ)

• exhaustive same info referred to in two places
  in f-structure, so split antecedence impossible
• local verb can only subcategorise for a clause
  contained in its own immediate constituent
• obligatory control pattern can only be
  introduced via lexical entry of controlling verb
• c-command (or f-command) controlling verb one
  clause up and thus subject/object/indirect
  object necessarily c-commands controllee

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persuade vs promise

• persuade lt(SUBJ), (OBJ), (XCOMP)gt
• (XCOMP SUBJ) (OBJ)
• promise lt(SUBJ), (OBJ), (XCOMP)gt
• (XCOMP SUBJ) (SUBJ)

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Lexical form for seem

• seem seem lt (XCOMP) gt (SUBJ)
• (XCOMP SUBJ) (SUBJ)
• NB (SUBJ) outside the angle brackets shows it
  is syntactically but not semantically selected

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F-structure for seem
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believe

• believe lt(SUBJ), (XCOMP)gt (OBJ)
• XCOMP SUBJ OBJ

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a-control vs f-control
Functional control (models oblig control) Anaphoric control (models non-oblig control)
Structure sharing Co-reference
Open functions Closed functions
Corresponds to PRO Corresponds to pro
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Keep ing

• Susan discussed visiting Fred (anaphoric)
• ii) Susan kept visiting Fred (functional)

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• Passive
• Visiting Fred was discussed/kept by Susan
• Cleft
• It was visiting Fred that Susan discussed/kept

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• Tough
• Visiting Fred is unpleasant for Susan to
  discuss/keep
• Gen subj
• Susan discussed/kept our visiting Fred

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Mechanism of a-control

• Add the optional equation
• (? GF PRED) pro
• to the lexical entry of a non-finite verb

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To visit Fred will annoy Susan
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ObviationEnglish want vs Italian volere

• Bill wanted to visit Fred
• Bill wanted Susan to visit Fred
• Memo voleva visitare Federico
• Bill wanted visit.INF Fred
• Memo voleva che Susanna visitasse Federico
• Bill wanted that Susan visited Fred

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Wh-movement

• Involves link between a filler and a gap
• What did Bill put e in the box?
• filler gap

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Unboundedness vs islands

• Potentially infinite distance between filler and
  gap
• Who did Bill want Sally to try to invite e?
• Yet certain close dependencies are not OK
• What did Bill believe the report Sally said?
• (Complex NP Constraint)

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Wh-constructionsthe challenge for LFG

• Can we avoid recourse to empty categories?
• The construction seems to refer to
  categories/positions not functions
• a) all categories except VP front
• b) categories move to a specific c- structure
  position

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DFs vs GFs

• A functional account needs to identify a
  function for the wh-element
• TOPIC old information relatives topics
• FOCUS new information questions
• SUBJ grammaticalized DF default topic

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Functional dependenciesoutside-in
Who did Bill visit? (?FOCUS) (?OBJ)
Who did Bill try to visit? (?FOCUS) (? XCOMP OBJ)
Who did Bill say that Susan visited? (?FOCUS) (? COMP OBJ)
Who did Bill say that Susan tried to visit? (?FOCUS) (? COMP XCOMP OBJ)
etc etc
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Functional dependenciesinside-out
Who did Bill visit? (?OBJ) (? FOCUS)
Who did Bill try to visit? (?OBJ) ((XCOMP ?? FOCUS)
Who did Bill say that Susan visited? (?OBJ) ((COMP ?? FOCUS)
Who did Bill say that Susan tried to visit? (?OBJ) ((COMP XCOMP ?? FOCUS)
etc etc
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Functional uncertainty

• The infinite set of possible dependencies
  requires a means of selecting the right one for
  the sentence in question
• (?DF) (? GF GF) (Outside-in)
• (?GF) ((GF?? DF) (Inside-out)

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Outside-in functional uncertainty

• filler-gap relation expressed solely at
  f-structure with no empty c-structure
• Island constraints statable as conditions on the
  path from filler function to gap function
• (? DF) (??COMP, XCOMP (GFCOMP))

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Off-path constraints

• (? DF) (??COMP, XCOMP (GF))
• Only COMP and XCOMP can intervene between filler
  and gap
• So Complex NP Constraint follows since NPs cannot
  be COMPs or XCOMPs

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Inside out functional uncertainty(IOFU)

• there is an empty node in c-structure
• the empty node is annotated with the equation
  (?GF) ((GF?? DF)
• provided there is a legitimate path from the gap
  to the required focus or topic function the
  equations can be solved and the structure is
  allowed

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Why IOFU?

• f- /c-structure correspondences
• weak crossover effects
• wh- in situ and scope

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Canonical structural realization

• SUBJ and OBJ must be realized as nominals (NP or
  DP) (Bresnan 2001)
• a) That he would be late, I never would have
  believed. (That he would be late COMP)
• b) That he would be late was widely
  predicted. (That he would be late ?)
• c) Under the bed, we said they would find
  him. (Under the bed ADJ)
• d) Under the bed is where they found
  him. (Under the bed ?)

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CSR (cont.)

• If that he would be late in (b) is COMP,
• and if under the bed in (d) is PP, then CSR is
  violated.
• So, assume a null expletive subject e

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Weak Crossover

• Who does his mother like e? (who ? his)
• f-precedence a piece of f-structure f f-precedes
  a piece of f-structure g if the rightmost node
  associated with f precedes the rightmost node
  associated with g.
• A pronominal P cannot f-precede a constituent on
  which P is referentially dependent.