Onthenatureoflinguisticcomputations:complexity,development,andevolution.

LuigiRizzi

UniversityofSiena

StructureofthetalkI. Languageasacomputationalsystem:

• Someelementsoflinguisticcomputations:Structurebuilding,movement,interfaces,locality.

• Howtomodellanguageinvarianceandvariation:Ontheformatandlocusofparameters.

II.Languagevariationandlanguageacquisition:

• Ontheearlyacquisitionofabstractword‐orderproperties:anexperimentalresult.

III.AtypologyofMerge:acomplexityscaleanditsimplicationsforlanguageacquisition,adultknowledgeoflanguageand,possibly,fortheevolutionoflanguage.

Theunboundedscopeofthehumanlinguisticcapacities

• Weconstantlyunderstandandproducenewsentences,combinationsofwordsthatwehaveneverencounteredinourpreviouslinguisticexperience

• …andstillwefindthemfamiliarandusable.

• Galileo,Descartes,Humboldt,…

Elementsofsyntacticcomputations:generativemodels

• Thelinguisticcapacitiescanbemodelledasthepossessionofacomputingmachine(Chomsky1957),consistingofatleasttwokindsofentities:

• ‐Inventories,listsofelementsstoredinmemory(words,…)

• ‐Computationalprocedures,puttingtogetherelementsdrawnfromtheinventoriestoformhigherorderunits(phrases,sentences,…),recursive.

• PHONSYNTAXSEM

Alternativestoacomputationalapproach?

Coulditbethatwejustmemorizefragments,sequencesofwordsandretrieveandreusethem?

‐ No:weclearlyhavethecapacitytogobeyondwhatwehearandgeneratenewstructures.

Coulditbethatwecreatenewsentencesthroughanalogicalgeneralizationfrommemorizedfragments?

‐ Thisstatementacquiresacontentonlyifwetrytomakeprecisewhat“analogicalgeneralization”means,thusexplainingwhycertainconceivable“analogicalgeneralizations”areneverconsideredbythelanguagelearner.

Recentdevelopments:Inventories

• Inventories:shiftofemphasisfromthecontentivelexicon(N,V,A,…)tothefunctionallexicon(D,Aux,C,T,Asp,…)

Functionalelements:‐createconfigurationalskeletafortheinsertionofcontentive

elements;‐ triggerthefundamentalcomputationalprocesses;‐ expressbasicparametersofvariation;‐ giverisetocomplexconfigurations,studiedin“cartographic”

projects(Rizzi1997,Cinque1999,etc).

Recentdevelopments:elementarycomputations

• Computations:shiftfromconcrete,construction‐orientedrules(forrelatives,questions,passives,…)tomoreabstractcomputationalingredients:

‐ Merge,

‐ Move,

‐ Spell‐out.

Mergeasthefundamentalrecursiveprocedure

• Merge:

C 2(1)ABAB

whereC=A,orC=B:theselectingelementprojects.

Chomsky(1995,2001)

Aderivation

[meetBill]

[can[meetBill]]

[Mary[can[meetBill]]]

[that[Mary[can[meetBill]]]]

[said[that[Mary[can[meetBill]]]]]

[has[said[that[Mary[can[meetBill]]]]]

[John[has[said[that[Mary[can[meetBill]]]]]

Atree

(3)T 3N T John 3 TV has 3VCsaid3CTthat3NTMary 3 TV can 3 VNmeetBill

Adevelopment:thecartographyofsyntacticstructures‐theCsystem(Rizzi1997,2004)

ForceP3

3ForceTopP 33TopIntP

3 3IntFocP

33 FocModP

3 3ModFinP

33

FinClause

TheC‐systemofItalianForceP

3 3ForceTopPche 3aGianni3TopFocP3QUESTO3 FocModP

3 domani3ModFinP

33

FinClause

glidovrestedire

CredocheaGianni,QUESTOdomaniglidovrestedire

‘IbelievethattoGianni,THIStomorrowyoushouldsay’

Movement

• Expressionsareoftenpronouncedinapositiondifferentfromthepositioninwhichtheyareinterpreted.

(6)aWhichbookshouldIread___?bWhichbookdoyouthinkIshouldread___?cWhichbookdoyouthink…theprofessorsaid…weshouldread___?

(7)a[___C[Ishouldread[whichbook]]]MOVEb[[whichbook]should+C[you___read___]]

MovementasSearch+Merge:InternalMerge

(1)[Q[theboy][saw[whichgirl]]]Search

(2) [Q[theboy][saw[whichgirl]]]InternalMerge(3) [[Whichgirl][Q[theboy][saw<[whichgirl]>]]]

InternalandExternalMergearededicatedtotheexpressionoftwotypesofsemanticproperties:

‐ ExternalMergeexpresses(amongotherthings)argumentalsemantics(whodoeswhattowhom).

‐ InternalMergeexpresses(amongotherthings)Scope‐Discoursesemantics(Scopeofoperators,topicality,focus,etc.).

DivisionoflaborofExternalandInternalMerge,andtwokindsofinterpretivepropertiesatthe

interfaceswithsemanticsandpragmatics

(1) [I[will[read[yourbook]tomorrow]]]Ext.Merge

(2)Top[I[will[read[yourbook]tomorrow]]]Search

(3)Top[I[will[read[yourbook]tomorrow]]]Int.Merge

(4)[yourbook]Top[I[will[read<[yourbook]>tomorrow]]]

Theexpressionyourbookismergedintwopositions,whereitpicksuptheinterpretivepropertiesof“patientofread”and“topic”,respectively.So,ExternalandInternalMergearenotjustrulesofaformalgame,butplayacriticalroleattheinterfaceswithsemanticsandpragmatics.

DivisionoflaborofExternalandInternalMerge,andtwokindsofinterpretivepropertiesatthe

interfaceswithsemanticsandpragmatics(1) [I[will[read[yourbook]tomorrow]]]Ext.Merge

(2)Foc[I[will[read[yourbook]tomorrow]]]Search

(3)Foc[I[will[read[yourbook]tomorrow]]]Int.Merge

(4)[yourbook]Foc[I[will[read<[yourbook]>tomorrow]]]Ext.M

(5)Itis[yourbook]Foc[I[will[read<[yourbook]>tomorrow]]]

LanguageswhichovertlyexpressScope‐discourseheads

(5)aIkweetniet[wieof[Jan___gezienheeft]]

‘IknownotwhoQJanseenhas’

(Dutchvarieties,Haegeman1996)

bUnsè[do[danloyà[Kofihuì]]]

‘IheardthatsnaketheTopKofikilledit’

(Gungbe,Aboh2004)

cUnsè[do[danlowè[Kofihu___]]]

‘IheardthatsnaketheFocKofikilled’

(Gungbe,Aboh2004)

Theinterfacewiththesoundsystem:Pitchcontouroftopic‐commentandfocus‐presuppositioninItalian(Bocci2009)

H+ +L* L-L% H+ +L* H+ +L* H+ +L* H+ +L* L-L%

a mi he lan d_elo d_er ma ni ho vo r! beprezen ta re pje ran d_ela

A Michelangelo Germanico vorrebbe presentare Pierangela

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0 3.7942

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a mi he lan d_elo d_er ma niho vo r!bbeprezen ta repje ran d_ela

A MICHELANGELO Germanico vorrebbe presentare Pierangela

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Locality

(1) Howdoyouthink[hebehaved___]

(2) *Howdoyouwonder[whobehaved___]

RelativizedMinimality:in…X…Z…Y…

AlocalrelationcannotholdbetweenXandYacrossanintervenerZifZisofthesametypeasX.(Rizzi1990,2004)

(3) *Howdoyouwonder[whobehaved___]

*

XZY

Spell‐outandtheinterfacewithsound

Certainpositionsarepronounced,henceatthePFinterfacetheyactivateinstructionsforthearticulatorysystem.

OtherpositionsarevisibleontheLFinterface,buttheyarenotspelledoutonthePFinterface:

(1)aJohnipromisedBillk[PROitoshavehimselfi]

bJohnipersuadedBillk[PROktoshavehimselfk]

(2)WhichpictureofhimselfididJohnichoose___?

(3)WhichpictureofhimselfididJohnichoose<whichpictureof

himselfi>

Languageinvarianceandvariation

Comparativelinguisticstudiesshowthatsomepropertiesvaryacrosslanguages,whileotherpropertiesareinvariant.

Withinthetraditionofgenerativegrammar,invarianceandvariationisexpressedbytwotheoreticalobjects:

‐ Particulargrammars,whichexpressesthepropertiesspecifictoaparticularlanguage,and

‐ Universalgrammar,whichexpressestheuniversalarchitectureoflanguage.

Languageinvarianceandvariation:principlesandparametersofUniversalgrammar

• Universalgrammar:asystemdefiningthegeneralarchitecturecommontoallhumanlanguages,specifyingasetofuniversalprinciplesandleavingopenasetofchoicepoints,theparameters.

• Particulargrammar:UGwithparameterssetinaparticularway.(Chomsky1981)

(inspiredbyworkinfundamentalbiology:Monod,Jacob,etc.)

• Parametricmodelsintroduced:‐Apowerfultechnicallanguagefordoingcomparativesyntax;‐Aviablemodeloftheacquisitionofsyntax:obscureideason“rule

induction”werereplacedbyaclearoperationofselectionofparametricvalues.

Ontheformatandlocusofparameters

Formatofparametersis:

(1)“HhasF”

whereHisafunctionalheadandFisafeatureactingasaninstructionforaparticularsyntacticaction:Merge,Move,Spell‐out.

Locus:Parameters,initiallyconceivedasspecificationsonprinciples,aremorenaturallyexpressedasspecificationsinthefunctionallexicon.

Atypologyofparameters

• Mergeparameters: ‐whatcategorydoesHselect?

‐totheleftortotheright?

• Moveparameters:‐doesHattractalowerhead?‐doesHattractaphrasetoitsSpec?

• Spell‐outparameters:‐isHovertornull?

‐doesHlicenseanulldependent?

Ontheformatandlocusforparameters

(21)Currentassumptionsonthenumerosityofparametersaresometimestakenasakindofreductioadabsurdumoftheveryideaofparametricsyntax,theideathatsyntacticdiversityisamenabletoafinitesetofbinaryoptions;so,thecurrentconceptionissometimesseenasanundeclaredretreattotheESTconceptionofgrammarsassystemsoflanguage‐specificrules.

(22)Butthereisaconfusionherebetweenthelocusandtheformatofparameters:underthecurrentconception,thelociofparametersarequitenumerousanddiverse,buttheformatisextremelyrestrictive,asdeterminedbytherestrictivenessofminimalistsyntax.So,theparametricspaceisradicallymorerestrictedthanthespaceofpossiblelanguage‐specificrulesinESTmodels.ParametersreducetotriggeringthebasicsyntacticactionsofMerge,MoveandSpell‐out.

Amergeparameter

Allhumanlanguagesaremerge‐based,butthereisafundamentalorderingparameter:

(1)Aheadprecedes/followsthecomplement.

NB:Thisalsoconcernsv,n,etc.,thefunctionalheadswhichassignacategorialstatustoalexicalroot.

Coherenthead‐initialandhead‐finallanguages:

(2)aJohnhassaid[thatMarycanmeetBill]

bJohn‐wa[Mary‐gaBill‐nia‐eru‐to]itte‐aru‘John‐Top[Mary‐NomBill‐Datmeet‐can‐that]said‐has

VOandOVLanguages

T

T N

John

T

has

V

said

V

C

that

N

Mary

V

meet

N

Bill

C

T

V T

can

T

(1) (2)

T

T N

John-wa

T

-aru

V

itte-

V

C

to N

Mary-ga

V

a- N

Bill-ni

C

T

V T

-eru-

T

Interimsummary

Somepropertiesoflanguagedesignthatthestudyoftheevolutionoflanguageshoulddealwith:

‐ Inventories:thecontentiveandfunctionallexicon;

‐ Computations:structure‐building‐ Computations:Movement

‐ Principlesattheinterfaceswithsoundandmeaning

‐ Localityprinciples

‐ Invarianceandvariation• Howarethesepropertiesacquired?

• Howaretheyimplementedinthebrain?

• Howdidtheyariseinevolution?

Theacquisitionofwordorderproperties

• Theparametricapproachexpectsthattheacquisitionoflanguage‐specificpropertiesshouldbefast:theproblemiswell‐defined(selectingoneoftwopossiblechoices)andthechildisguidedbydomain‐specificcognitiveresources.(Wexler’sVEPS)

• Infact,earlyproductionsinthetwowordsstagealreadyconformtothebasicwordorderofthetargetlanguage,VOorOV,asVEPSpredicts(Poeppel&Wexler1993).

• Butitcouldbethatatthisearlystagethechildsimplyreproducesfragmentsthathehears,andthatabstractgrammaticalknowledgeisdevelopedmuchlater(asin“constructivist”approaches).

• SO,theimportantquestionarises:howearlydoesthechildpossessabstractgrammaticalknowledge?

J.Franck,S.Millotte,A.Posada,L.Rizzi(2010)Abstractknowledgeofwordorderby19months:Aneye‐

trackingstudy.

Subjects:19monthsoldinfantsexposedtoFrench

Theexperimentcombines:

‐ The“preferentiallooking”paradigm;‐ Pseudo‐verbs(jabberwocky).

‐ The“weirdwordorder”paradigm:

GrammaticalNPVNPsentences:(1)Lelionpounelecheval

UngrammaticalNPNPVsentences:

(2)L’ânelechiendase

Preferentiallookingparadygm(Hirtsh‐Pasek&Golinkoff1996)

« Hey, she’s kissing the keys! »

Vidéo Match Vidéo Mismatch

Cond ition

Aud iosentence

Video 1Transitiveaction

Video 2Intransitiveaction

NVN Le lion pounele cheval

The lion ispoun ing thehorse

NNV L’âne le ch iendase

The donkeythe dog isdasing

ResultsJ.Franck,S.Millotte,A.Posada,L.Rizzi(2009)Abstractknowledgeofword

orderby19months:Aneye‐trackingstudy.

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Transitive action

Intransitive action

Results

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NNV

ConclusionsInfantsat19monthsexposedtoFrenchclearlyinterpretNPVNP

structuresasAgent–Action–Patientwithnovelverbs,whiletheyhavenopreferencefortheinterpretationofNPNPVstructures.

TheythusappeartohaveabstractknowledgethatthelanguagetheyareexposedtoisSVO.

Iftheinfanthadnoabstractknowledge(“mylanguageisSVO”)andwassimplymemorizingnewverbswiththeirsyntacticenvironment,noselectivepreferenceforthetransitiveinterpretationwithNPVNPwouldbeexpected:theinfantwouldjustmemorizethenewverbwithitsidiosyncraticenvironment,andwouldhavenobasistopreferthetransitivescenewithVO,butnotwithOV.

Cuesfortheearlyacquisitionofwordorder

‐Christophe,A.,Nespor,M.,Guasti,M.T.,&VanOoyen,B.(2003)showedthatbabiesat3monthsaresensitivetodifferencesinprosodicprominencecorrelatedtoOV‐VO(French‐Turkish).

‐Gervain,J.,M.Nespor,R.Mazuka,R.Horie,J.Mehler(2008)showsthatat10monthsinfantsexposedtoItalianprefertheorder[frequentWord–infrequentWord]inanartificiallanguage,whileinfantsexposedtoJapanesehavetheoppositepreference.

Aninterpretation

Areasonableconjectureisthatchildrenfixtheorderingparameterprelexicallyinthefirstyearoflife,onthebasisofprosodicandstatisticcues.

OncelexicalmeaningsofN’sandV’sstartbeingsystematicallyassociatedtosegmentedwords,childrenexposedtoFrenchcorrectlyinterpretSVOstructureswithnovelverbsonthebasisof:

‐ TheabstractparametricknowledgethatFrenchisSVO;

‐ Generalprinciplesdeterminingtheform–meaningmapping:asubject‐verb‐objectsentenceisinterpretedasexpressingabiargumentalaction,withthesubjectinterpretedastheagent,theobjectasthepatient.

“Languagefaculty”vs“Languageasculture”Q:Howisitpossiblethateverychildmanagestoacquireanaturallanguage,

anextraordinarilycomplexsystem?

‐“Languagefaculty”approaches:Thereisahumanlanguagefacultywhichseverelylimitstheclassofpossiblehumanlanguages.Thechildanalyzesincomingdataonthebasisofdedicatedcognitiveresourcesandquicklyselectsagrammaticalsystemonthebasisofexperience.

‐“Languageasculture”approaches:Theacquisitionofalanguageisliketheacquisitionofculture,ortechnology.Languagescanvaryindefinitely:therearecertaincontentstoexpress,thereareindefinitelymanyimaginablewaystodoso,linguisticcommunitiesmakeparticularchoicesandlanguagelearnersfigureoutwhatthesechoicesareasinanyothercaseofculturalacquisition,throughtheirgeneralintelligenceandproblem‐solvingcapacity(awidespectrumofapproaches,e.g.,Evans&Levinson2009,BBS).

“Aninstinctivetendencytospeak”

• [Language]certainlyisnotatrueinstinct,aseverylanguagehastobelearnt.

• Itdiffers,however,widelyfromallordinaryarts,formanhasaninstinctivetendencytospeak,asweseeinthebabbleofouryoungchildren,whilenochildhasaninstinctivetendencytobrew,bake,orwrite…

(C.DarwinDM1871)

Comparingthetwoapproaches

Theproblemofcomparingthepredictionsofthe“languagefaculty”andofthe“languageasculture”approachescanbeattackedfrommanyangles:

‐ Throughcomparativelinguistics(Baker2001):isitthecasethat“anythinggoes”inlanguage?

‐ Byassessing“povertyofstimulus”arguments(Chomsky)‐ Throughbrainimagingtechniques(Moroetal.2003):howdoesthebrain

process“possibleandimpossible”linguisticregularities?

‐ Throughtheexperimentalstudyoftheinitialcognitivestateofthenewborn(Mehleretal.)

‐ Throughthestudyofdevelopment:howearlydoesthechildmanifestknowledgeofuniversalproperties?Andoflanguagespecificproperties?

ThreekindsofMerge

Mergeisusuallyconsideredaunitaryformaloperation,butamorerefinedanalysisshowsthatthereisatypologyofcases,whichcanbenaturallyrangedalongadimensionofincreasingcomplexity.

PrimaryMerge:[thegirl]

RecursiveMerge:[saw[thegirl]]

PhrasalMerge:[[theboy][saw[thegirl]]]

Iteminred:selector

Itemingreen:selectee

PrimaryMerge

PrimaryMerge(orH‐HMerge)takestwoitemsfromthefunctionalorsubstantivelexiconandformsminimalphrases:

[thegirl][withMary]

[seepeople]

Operativememory:thelexicalarray,thearrayofwordsselectedfromthelexiconatthebeginningofeachsyntacticcomputation.

Non‐recursive.

RecursiveMerge

RecursiveMerge(orHead‐PhraseMerge):takesanitemfromthefunctionalorsubstantivelexiconandaphrasealreadyformed:

[the[tallboy]]

[see[thegirl]]

Operativememory:

I. thelexicalarrayand

II. amemorybufferinwhichthestructurealreadybuiltisstored.

Thisisthefundamentalrecursivestepinsyntacticcomputations.

TheheadselectingthephraseistheheadoftheconstructionandassignsitslabeltothenewentitycreatedbyMerge.

PhrasalMerge

Phrasal(orPhrase‐PhraseMerge)takestwocomplexphrasesalreadyformedbyMerge:

(1)[[theboy][saw[thegirl]]]

Operativememory:

I. Thelexicalarray(becauseselectionalpropertiesmustbe“seen”).

II. Aprimarymemorybuffer(containinganalreadyformedphrasewithanactive“selector”,liketheverbin(1)):[saw[thegirl]]

III. Asecondarymemorybuffercontaininganalreadyformedphrase:[theboy]

Recursive?Thepointiscontroversial.

Thelabeloftheconstructionisdeterminedbytheselector.

Movement:Search+PhrasalMerge

(1)[Q[theboy][saw[whichgirl]]]Search

(2) [Q[theboy][saw[whichgirl]]]PhrasalMerge

(3) [[Whichgirl][Q[theboy][saw___]]]

AsearchoperationconductedwithintheprimarybufferidentifiesacandidateforPhrasalMerge.Theidentifiedcandidateisthenmergedwiththewholestructure.

PhrasalmovementisacompositeoperationcombiningaSearchprocedurewiththepossibilityofphrasalMerge.

PhrasalMerge

• Phrase‐PhrasemergeismorecomplexthanHead‐Phrasemergebecauseitrequiresholdinginoperativememorytwostructurescomputedindependentlyandpotentiallyquitecomplex.

• AnindirectsignoftheaccruedcomplexityofPhrase‐PhraseMergemaybethereluctancethatyoungchildrenshowinnaturallyproducingSubject–Predicatestructureswithcomplexsubjects,andthetendencytodropdeterminersmoreinsubjectthaninobjectposition(Guastietal.2005).

(1)aTheboysawthegirlb___boysawthegirlMorelikely

cTheboysaw___girlLesslikely

PhrasalMerge

AnotherpossibleindirectsignofthecomplexityofphrasalMergeisthefactthatinadultsystemsphrasalspecifierstendtobe“islands”,whilephrasalcomplementsarenot:

(1)aJohnbought[apictureofMary]

bWhodidJohnbuy[apictureof___]?

(2)a[ApictureofMary]pleasedJohnb*Whodid[apictureof___]pleaseJohn?

Apparently,thecontentofthesecondarybufferistreatedasaunit,andisnotaccessibletofurthersyntacticoperations(Uriagereka1998),whilethecontentoftheprimarybufferremainsaccessible.

AMerge‐basedcomplexityscale

1.Selectionfromthelexicon:utteranceswithsinglewords.

(certainanimalcommunicationsystems;fragmentsoflanguagestaughttoapes?one‐wordstageinlanguageacquisition?)

2.PrimaryMerge:2‐wordutterances.

(2‐wordstageinacquisition?Predominantone‐ortwo‐signstructuresinhome‐signsystems,withveryfewmultiplesigns?)

3.RecursiveMerge:generatesanunboundedsetofutterancesoftheformHead–Phrase.

(possibly,astagereflectedinthereluctancethatyoungchildrenshowfortheproductionofcomplexspecifiers)

4.PhrasalMerge:permitsanunboundedsetofutteranceswithcomplexspecifiers,andcreatestheoptionofphrasalmovement.

Implicationsfortheevolutionoflanguage?‐ Thistypologyalsoinvitesthespeculationof4possiblesuccessive

stepsintheevolutionofsyntacticcomputations:

1. Simpleaccesstothelexicon,leadingtoonewordutterances;

2. PrimaryMerge,leadingtoatmosttwo‐wordutterances;3. RecursiveMerge,leadingtoapotentialinfinityofHead‐Phrase

utterances

4. PhrasalMerge,leadingtoapotentialinfinityofphraseswithcomplexspecifiers.

1seemstobecommonlyattestedinanimalcommunicationsystems.2representsthefirstrudimentarysteptowardacombinatorial

system;itsattestationincommunicationsystemsofnon‐humanprimatesishighlycontroversial,soitseemstobeattheborderofthecomputationalcapacitiesofsuchspecies.

RecursiveMerge

‐ Thecriticalevolutionarystepappearstobe3:recursiveMerge,whichpermitsmasteryofapotentialinfinityofstructures,possiblyresultingfroma“minorreorganisationofthebrain”(Hauser,Chomsky,Fitch).And/oracomputationalcapacityextendedtolanguagefromsomeothercognitivesystemwhereitpre‐existed(recursive“theoryofmind”?).

‐ Ofcoursetheemergenceofsuchacomputationalabilitycouldnottakeplaceinthevacuum:Mergecouldonlybeusedifthesystemalreadyincludedalexicon,alistofelementsfortherecursivecomputationstooperateon,andperhapstheintermediatecapacitytocombinelexicalitemsnon‐recursivelyinpairs(primaryMerge).

Phrasalmerge

‐ Theextrastep(4)ofpermittingPhrasalMergeispresumablylinkedtothenecessityofexpressingeventswithmorethanoneparticipant,instructuresinwhicheachparticipantmaybereferredtobyacomplexphrase.

‐ ThisyieldthepossibilityofproducingstructureswithcomplexSpecifiers…

‐ …anoptionwhichinturnopensthepossibilityforphrasalmovement,anoperationwhichplaysacriticalroleattheinterpretiveinterfaces,andissystematicallyfoundacrosslanguages.

Conclusion

Astudyoftheevolutionoflanguagecannotbeconductedwithoutanin‐depthunderstandingofthebasicingredientsandfunctioningoflinguisticcomputations.Ihavetriedtoprovideanoverviewofsuchcomputationsaccordingtocurrentformalmodels.

‐Therapidityoflanguageacquisitionandtheearlyappearanceofabstractsyntacticknowledgesuggeststhatthereisan“instinctivetendencytospeak”inourspecieswhichcallsforanevolutionaryexplanation.

Conclusion

AMerge‐basedcomplexityscaleseemstohaveapotentialexplanatoryvalueforthestudyoflanguagedevelopmentinnormalandspecialcircumstances,aswellasofadultlinguisticcomputations.

Itmaythushelpustoidentifymorerudimentaryprecursorsofmodernlanguagesyntax,whichmaystillbemanifestedinvestigialformsinlanguageacquisitionandlanguagecreationinspecialcircumstances.

Thankyou!

References

Christophe,A.,Nespor,M.,Guasti,M.T.,&VanOoyen,B.(2003).Prosodicstructureandsyntacticacquisition:thecaseofthehead‐directionparameter.DevelopmentalScience,6(2),211‐220.

Gerken,L.‐A.,Jusczyk,P.W.,&Mandel,D.(1994).Whenprosodyfailstocuesyntacticstructure:9monthsolds’sensitivitytophonologicalversussyntacticphrases.Cognition,51,237‐265.

Gertner,Y.,Fisher,C.,&Eisengart,J.(2003).Learningwordsandrules.PsychologicalScience,17(8),684‐691.

Gervain,J.,M.Nespor,R.Mazuka,R.Horie,J.Mehler(2008)Bootstrappingwordorderinprelexicalinfants:AJapanese–Italiancross‐linguisticstudy,CognitivePsychology,2008.

Hirsh‐Pasek,K.R.,&Golinkoff,R.M.(1996).Theoriginsofgrammar.Cambridge,MITPress.

Matthews,D.,Lieven,E.,Theakson,A.,&Tomasello,M.(2007).Frenchchilldrenuseandcorrectionofweirdwordorders:Aconstructivistaccount.J.ChildLanguage,34,381‐409.