rosen real definition 2nd draft
DESCRIPTION
Rosen Real Definition 2nd DraftTRANSCRIPT
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REALDEFINITION1
G.Rosen
Reviseddraft,February2015
[Thisversionisquitedifferentfromthepreviousdraft,datedSept.2013.]
1. Thetopic
TheoldSocraticquestionsWhatisjustice?Whatiscourage?callfordefinitions,
notofwordsorconcepts,butofthings.Justiceandcourageandthelikeweresupposed
to be aspects of reality. To answer the question What is courage? in the intended
sense is not to say what theword couragemeans or what passes before themind
when we think when we think of courage. It is to saywhat it is for a person to be
courageoustoidentifythat inwhichthecourageofthecourageouspersonconsists
by specifying nontrivial necessary and sufficient conditions for courage somehow
groundedinthenatureofcourageitself.
The case can bemade that contemporary analytic philosophy is up to its ears in
idiomsofdefinition,analysis,reductionandconstitutionthatarebestunderstoodina
similarly metaphysical keyas demands for real definition rather than linguistic or
conceptualanalysis.Onthisview,whenweaskwhatit isforathingtobeapersonor
foracreaturetobeconsciousorforafacttobealawofnatureorfortwoexpressions
tohavethesamemeaningorforanobjecttobecoloredorforanacttobefreeorfor
anartifacttobeanartwork,wearebestunderstoodasseekingrealdefinitionsofthe
properties, kinds, categories or relations that figure in the question, rather than
semanticorconceptualequivalents,evenwhenthenthecorrectnessoftheaccount is
1ThismaterialwaspresentedattheCRNAPWorkshoponMetaphysicalStructureat
PrincetoninApril2013,attheGenevaWorkshoponGroundingandExistencein
September2014,andatMIT.IamgratefultoRalphBader,SelimBerker,FabriceCorreia,
ShamikDasgupta,MarkJohnston,KathrynKoslicki,BarryMaguire,Michaela
McSweeney,KevinMulligan,JanPlateandAlexSkilesforcommentsandquestions.
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meanttoberecognizableapriori.Themainargumentforthisviewisthatwhenwetry
toanswer thesequestionswearehappy toentertainanalysescast in terms that fully
competentmastersoftheanalysandumneednotgrasp.Wesimplyhavenoconception
of semantic or conceptual analysis onwhich thismakes sense. And yet our analytical
questions and our practice with them do make sense. And this suggests that our
questions are not semantic or conceptual questions after all. They are rather
metaphysicalquestionsthatcallfordefinitions,notofrepresentationalitems(wordsor
concepts)butofpropertiesandotherfeaturesofmindindependentreality.
Inmytravels Ihaveencounteredresistancetothis idea,evenamongphilosophers
who are otherwise sanguine about the recrudescence of premodernmetaphysics in
postmodernphilosophy.Thebestwaytoovercomethisskepticismwouldbetoexplain,
in clear and independently intelligible terms,what it is to define a thing, or in other
words,toprovidea(real)definitionof(real)definition.Theaimofthepresentnoteis
todojustthat.
2. Preliminaries
Intheorywecanaskfordefinitionsofitemsinanycategory:objects,properties,
relations,connectives,quantifiers,etc.,allunderstoodasworldlythingsandnotasbits
of mind or language (special cases aside). But it will simplify discussion to focus on
propertiesandrelations.Wewrite
Def(F,)
forourtarget:tobeFistobe;beingFconsistsin,orreducesto,being,etc.Asthe
notationsuggests,itwillbeusefultothinkofDefasarelationbetweenthepropertyto
be defined and something else, its definiens. More concretely, I think of as a
structuredcomplex,builtfromworldlyitemsinroughlythesenseinwhichasentenceis
builtfromwords.(ThinkofasastructuredRussellianpropositionalfunctionwithfree
variablescorrespondingtotheargumentplacesinF.) Thisrelationalanalysisisstrictly
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optional.Defcouldbeaconnectiveinstead.Butitwillbeimportanttobeabletospeak
oftheconstituentsof.Thusifwesay(asweshould)thattobeanevennumberisto
bedivisibleby2,weshouldbeabletoaddthatthenumber2figuresinthedefinitionof
evennumber.Itakethistomeanthat2thenumberitselfisaconstituentofthe
complex in terms of which the property is defined. So even if the property is
mereologically simple, as it may be, its definiens is not. On this conception, real
definitionsarenot identities(thoughtheymayentail identities). Rathertheypairone
(possibly simple) thing thedefiniendumwithanother (invariably complex) thing,
itsdefiniens.Thechallengeistosaywhatittakesforapairingofthissorttoconstitute
acorrectdefinition.2
3. Asimplemodalaccount
Beginwithasimpleproposal:
(0) Def(F,)iffx(Fxx)3
2Def(F,)presumablyentails:ThepropertyofbeingF=thepropertyofbeing.ButitdoesnotfollowfromthisthatFandmustbeidentical.Tomakesenseofthis,thinkofthethepropertyofbeingasstandingforafunctionfrompredicableitems
(propertiesandcomplexes)toproperties.ThepropertyofbeingFisnotidenticaltothe
complex.Butitmaybeidenticaltothevalueofthisfunctionwhenistakenasitsargument.See9forfurtherdiscussion.
3ThisandsubsequentanalysesofDefshouldreallybewritten,notassimple
biconditionals,butasclaimsoftheform:
Def(Def(F,),(F,)))
Thatis:ForittobethecasethatdefinesFisforittobethecasethatFandstandinsuchandsucharelation.Butthisbecomesillegibleveryquickly,sowestickwiththe
shorthandiff.
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This is immediatelyobjectionablebecause itentailsthateveryproperty isdefinable
Def(F,F),whereas in the sense that interestsus, it isalwaysa substantivequestion
whetherFisdefinable.4WemightrespondbyrequiringthatFnotfigurein.Buteven
withthisstipulationtheaccountwillovergenerate for familiar reasons. Necessarily,a
thingisgreenifandonlyifitisgrueandobservedorbleenandunobserved(Goodman
1947).Butnoonewithaninterestinthemetaphysicsofcolorwouldacceptthisasan
accountofwhatitisforanobjecttobegreen.
4. ALudovicianaccount
Themostconservativemodificationofthesimplemodalviewinvolvesonenewbit
of ideology: David Lewiss idea that some properties are more natural than others
(Lewis 1983). The idea can be explained inmanyways, but lets start with following
roughgloss.Someclassesaremorehomogeneous,moreunified, lessgerrymandered,
thanothers.Thegreenthingsdifferinvariousways:insizeandshape,butalsoincolor,
some being emerald green, others chartreuse. But the grue things are even more
heterogeneous,sincetheycandifferinallofthesewaysbutalsomoreradically,some
beinggreenandothersblue.Ononeview,thenaturalnessofapropertyisameasureof
thehomogeneityofitsintension:
F is more natural than G iff (quantifying over all possible objects) the most
dissimilarFsarelessdissimilarthanthemostdissimilarGs.
Thismaynotbealtogetheradequateasadefinition;butitsafairapproximationofone
versionofLewissidea.
4ManywritersnotethattheidiomsweusetoexpressrealdefinitiontobeFistobe
,beingFjustisbeing,etc.canbeheardasreflexive.Itsoundsperfectlytrue,ifuninteresting,tosaythattoberedistobered.Itakethepoint,andsodenythatImin
thebusinessofexplainingthisordinaryidiom.AsIunderstandtheterm,ifthebestwe
candowithredistosaythatbeingredisbeingred,thentheupshotisthatredisnot
definableintheintendedsense.
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Withthisinhand,wemightconsideranamendedversionofthemodalaccount
ofrealdefinition:
(1) Def(F,)iffx(Fxx),
wheretheconstituentsofareallmorenaturalthanF.
Thisrulesoutcirculardefinitions,andalsothespuriousdefinitionofgreen intermsof
grueandbleen.Butconsider:
Tobeasquareistobeanequilateralrectangle.
Thismightbeacorrectrealdefinitionofsquare.Buttheconstituentsofthedefiniens
rectangle and equilateral are less natural than square, at least according to the
accountsketchedabove:theclassofrectanglesismorediversethantheclassofsquares.
Everycorrectdefinitionbygenusanddifferentiaisacounterexampletothisproposal.
Lewis sometimes hints at an account of relative naturalness that would avoid
thisproblem(Lewis1986:61).Onthisaccount,relativenaturalnessisdefinedinterms
ofthenotionofaperfectlynaturalpropertythesortorpropertythatmightfigureina
fundamental law of nature, the sort of property that might correspond to an
Armstrongian universal (Armstrong 1978), the sort of thoroughly determinate, non
disjunctive property that makes for perfect resemblance in some respect among its
instances.Takingthisnotionasbasic,thealternativeaccountmaintainsthat
F ismorenatural thanG iff theshortestdefinitionofF (i.e., theshortestopen
sentence cointensive with F) in a language whose predicates correspond to
perfectlynaturalpropertiesisshorterthantheshortestsuchdefinitionofG.
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Thisissharplyatoddswiththepreviousaccount.Afterall,whereFisperfectlynatural,
notFwillbealmostperfectlynaturalbythisaccount;butofcoursetheclassofnonFs
willbealmostmaximallyheterogeneous.5
The second account iswell suited to solve the problemsmentioned above for
modalaccountofdefinition.Eventhoughtheclassofrectanglesismoreheterogeneous
thantheclassofsquares,itisplausiblymorenaturalthantheclassofsquaresaccording
tothesecondconceptionofrelativenaturalness.Afterall,theshortestcharacterization
oftheclassofsquaresinperfectlynaturaltermswillpresumablyconjoinanaccountof
theclassofrectangleswithanaccountofequilaterality,inwhichcasethedefinitionof
squareinperfectlynaturaltermswillbelonger.
Thissolvesoneproblemforthemodalaccountofrealdefinition,buttheaccount
isunacceptableforotherreasons.Considerasupervenientproperty,liketheproperty
ofbeinganuncle.Thisisnotaperfectlynaturalproperty,butthefactsaboutwhoisand
who is not an uncle strongly supervene on the distribution of perfectly natural
properties: foranytwopossibleobjects,xandy, ifxandyarealike ineveryperfectly
natural respect (includingextrinsic respects), thenbothareunclesorneither is. As is
familiar,thissupervenienceclaimguaranteestheexistenceofanecessitateduniversally
quantifiedbiconditionaloftheform:
x(xisanunclex)
constructedas follows: Takeallof theuncles,actualandpossible:u1,u2, LetD1(x),
D2(x) be their complete descriptions in perfectly natural terms. (D1(x)might be a
completedescriptionofu1inthelanguageofquantumfieldtheory.)Thenconsider:
5LewismayhaveinmindaversionofthisideaonwhichthedefinitionsofFmustconsist
inpositiveformulae:conjunctionsofdisjunctionsofatomicformulaeinvolvingperfectly
naturalpredicates,withoutnegationortheequivalent.Butthentheworrywillbethat
mostordinarypropertieswillbedefinedonlybyinfinitaryformulae,inwhichcasethe
differencesbetween(say)greenandgruewillbelost.
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x(xisanuncle(D1(x)D2(x)))
Everyversionofthemodalaccountthatwehaveconsideredentailsthatthisisacorrect
accountofwhatitistobeanuncle.Butitisnt.Mostimportantly,itfailstobringout
whattheuncleshave incommon. It is likeadefinitionofprimenumberaccordingto
which to be a prime is to be either 2 or 3 or 5 or This account is not just less
informative than itmightbe: it iswrong. It isnotso that3 isprime invirtueofbeing
either 2 or 3 or 5 or ; 3 is prime in virtue of having 1 as its only proper factor.6
Similarly,itisjustnotsothatFesterisanuncleinvirtueofbeingconfiguredinthisfully
determinateway,orthatfullydeterminateway,orHeisanuncleinvirtueofbeinga
manwithasiblingorsiblinginlawwhoisaparent.
This points to another defect in the disjunctive account: it isoverly specific.A
correct definition of uncle should notmention quarks, even though some uncles are
madeof quarks, just as a correct definitionofhouse shouldnotmentionbricks. The
propertyofbeinganuncle isafunctionalproperty inthefollowingsense: itsnature
allows for many fully determinate ways in which a thingmight be constituted as an
uncle,butdoesnotspecifythesewaysindetail.Toknowwhatitisforapersontobean
uncle is to know that uncles must be made of something; but it is not to know an
exhaustivelistofthevariouswaysinwhichanunclemightbeconstituted.7
5. Anessentialistaccount
Theoverspecificityobjectiontomodalaccountsofdefinitionsuggestsadifferent
approach.KitFinenotesthatinmanycases,andperhapsinall,whenaproposition
holdsofmetaphysicalnecessitywecanpointtooneofmoreitemswhosenatures
groundthatnecessity(Fine1994).SupposeJackis,ofnecessity,Tarzansson.Thenwe
canbeconfidentthatthisisso,notbecauseitliesinTarzansnaturetobeJacksfather,
6Foranobjectiontolistdefinitionsfromadifferentquarter,seeField1972:362ff.
7Canwesavethemodalaccountsbyrequiringthatrealdefinitionsbefinite?That
wouldbeunmotivated.Whyshouldnttherebeitemsthatcanonlybedefinedin
infinitarytermsarbitraryinfinitesets,forexample?
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butratherbecauseitliesinJacksnaturetobeTarzansson.Toputthepointin
epistemicterms,youcanknoweverythingthereistoknowaboutTarzansessential
naturewithoutknowingthefirstthingaboutJack;butyoucantknowJacksessential
naturewithoutknowingthatTarzanishisfather.Similarly,itmaylieinthenatureof
tablesalttocontainchlorinewithoutitslyinginthenatureofchlorinethatsaltshould
containit.InFinesnotation:
JackTarzanisJacksfather,butnot:TarzanTarzanisJacksfather
saltSaltcontainschlorine,butnot:chlorineSaltcontainschlorine
Fineshowsconvincinglythatthishyperintensionalidiomcanbemadeclear(in
severalways),andthatitissuitableforuseinsystematicmetaphysicsevenifitcannot
bedefinedinmorebasicterms(Fine1995,2000).Soletshelpourselvestoitand
considertheproposal:
(2) Def(F,)iffFx(Fxx)
Thisavoidsmostofthepitfallswehaveencountered.Itdoesnotlieinthenatureof
greenthatathingisgreeniffgrueandobservedorbleenandunobserved.Acomplete
accountoftheessenceofgreenmightsaysomethingaboutthevariousshadesofgreen,
oraboutwavelengthsoflight;butitwouldnevermentiongrueoranythingofthesort.8
Thenecessarytruthconnectinggreenwithgrueandbleenisrathergroundedinthe
naturesofgrueandbleen;itisbecausethesepropertiesarewhattheyarethatthetruth
inquestionholds.Similarly,itdoesnotlieinthenatureofunclethatonewaytobean
uncleistosatisfysomemaximallydeterminatephysicaldescriptionD1(x),muchlessthat
oneisanuncleiffoneiseitherD1orD2orRatheritliesinthenatureofunclethat
8Exceptperhapsinsometrivialway:Ifessencesareclosedunderlogicalconsequence,
thenitwillinthenatureofgreenthateverythingiseithergrueornotgrue.
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oneisanuncleiffoneisamalesiblingorsiblinginlawofaparent.Nothingaboutthe
detailedphysicalnaturesoftherelevantitemsentersin.
Nowonemaywonderwhatsortofadvanceitcouldbetoexplainourtarget
idiomrealdefinitionintermsofFinesnotionofessence,sincethetwoare
obviouslyveryclose.9Soitsworthstressingthatthesenotionsarenotsimply
equivalent.OnFinesaccount,absolutelyeverythinghasanessence.Givenanyitemx,
definableornot,therewillbetruthsoftheformxp.EveniftheGettierexamples
showthatknowledgeisunanalyzable(Williamson2000),itstillliesinthenatureof
knowledgethatifSknowsthatpthenpistrue.Similarly,whilenegationisalmost
certainlyindefinable,itnonethelessliesinthenatureof(classical)negationthatp
~~p.TheseexamplessufficetoshowthatFinesconceptofessenceisdifferentfrom,
andmoregeneralthan,theconceptofrealdefinitionwevebeendiscussing.Onemight
acceptFinesideologyandstillwonder:Whatisitfortoconstituteacorrectreal
definitionofF?Theaccount(2)isdesignedtoanswerthatquestion.
Isitagoodanswer?Notobviously.Weobjectedtothesimplemodalproposal
(0)becauseitentailedthateverypropertydefinesitself:Def(F,F).Thepresentaccount
facesasimilarproblem.ItisnaturaltosupposethatforanypropertyF,Fx(Fx
Fx).Butinthatcase(2)entailsthateverypropertydefinesitself.
WemightrespondbyrequiringthatFnotoccurin.Butinfactthisrestriction
followsfromamoredemandingrestrictionthatisneededanyway.Supposewe
discover(bywhateverpowerfulmethodsweemployforthesepurposes),that
causexy(xcausesyiffyisaneffectofx),and
effectxy(xcausesyiffyisaneffectofx).
Proposal(2)thenentailsthatcausecanbedefinedintermofeffectandviceversa,and
theremaybeasenseinwhichthisisso(cf.thesenseinwhichconjunctioncanbe
9Finehimselfsometimesspeaksofessenceanddefinitionasifthenotionswere
interchangeable.Fine1994(REF).
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definedintermsofdisjunctionandnegation).Butthereisalsoobviouslyasensein
whichifthisisthebestwecando,therightthingtosayisnotthatcauseadmitsofan
easydefinition,butratherthatcausationisprimitiveandindefinable.(Thedefinitionof
causeintermsofeffectisnotacandidateanswertothequestionthatproponentsof
philosophicalanalysesofcausationhavebeenasking.)
Theneededmodificationisstraightforward.FollowingFine(1994b),saythata
dependsonbwhenbfiguresnontriviallyinasessence:
adependsonbiffa[b],butitsnotthatcasethatax(x).
Wecanthensay:
(3) Def(F,)iffFx(Fxx),wheretheconstituentsofdonotdepend
onF.
Thisrulesoutcirculardefinitionsanddefinitionalcircles(likethedefinitionofcausein
termsofeffectandviceversa).Moreovertheaddedclauseisnotadhoc.Itmakes
sensethattheconstituentsofadefinitionshouldbeontologicallypriortothething
defined(SeeKment2014:159foraversionofthisproposal).
Thisaccountmayseemtoovergenerate.Tobeaprimenumberistobea
numberwhoseonlyfactorsare1andn.Butconsiderthespuriousdefinition:
Tobeaprimeistobeanevennumberwhoseonlyfactorsare1andn,oranodd
numberwhoseonlyfactorsare1andn.
Orconsiderthelistdefinitionmentionedabove:
Tobeaprimeistobeeither2or3or5or
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Thesearebaddefinitionsofprime,buttheymightsatisfy(3),andiftheydo,(3)is
inadequate.
Thisproblemarisesifweassumethatessencesareclosedunder
logical/mathematicalconsequence,soonemightseektoevadeitbyinvokinganotion
ofessenceonwhichthisisnotso.Finehimselfdistinguishestheconstitutiveessenceof
xfromtheconsequentialessenceofx,withtheformerstandingtothelatterroughlyas
theaxiomsofatheorystandtothetheoryitself.Theconsequentialessenceofxisa
classofpropositionsclosedunderlogicalconsequence.Theconstitutiveessenceofxisa
privilegedsubclassthatservestogeneratetheconsequentialessence.Itmaylieinthe
consequentialessenceofSocratesthatSocratesishuman,andalsothatSocratesis
eitherhumanorsimian.Butonlythefirstpropositionisacandidateforinclusionin
Socratesconstitutiveessence.InhisformalworkFinemainlyoperateswiththenotion
ofconsequentialessence,sinceheseesnogoodwaytoisolatetheconstitutiveessence
fromamongthecompetingaxiomatizationsoftheconsequentialessence.Buthowever
difficultitmaybetoapplythenotioninpractice,theunderlyingideaseemsclear
enough.Wemaydefineconstitutiveessenceintermsofconsequentialessenceas
follows.
pbelongstotheconstitutiveessenceofxiff(a)pbelongstotheconsequential
essenceofx,and(b)therearenopropositionssuchthat:pbelongstothe
consequentialessenceofxinvirtueofthefactthatbelongstothe
consequentialessenceofx.
IfitspartoftheconsequentialessenceofSocratesthatSocratesiseitherhumanor
simian,thisissobecause,orinvirtueofthefactthat,itisindependentlypartofthe
consequentialessenceofSocratesthatSocratesishuman.Whateverdifficultywemay
haveinisolatingtheconstitutiveessenceofathinggivenitsconsequentialessence
derivesfromourlimitedcapacitytodeterminewhenoneessentialisttruthisgrounded
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inanother.Thatsarealproblem,butitsanepistemicproblem.Theconceptsareclear
enough,eveniftheyarehardtoapplyinpractice.
Withthenotionofconstitutiveessenceinhand,wecansolvetheovergeneration
problemfor(3).Thespuriousdefinitionsofprimemaybepartsoftheconsequential
essenceofprime.Buttheyarecertainlynotpartsoftheconstitutiveessence.Soifwe
readFin(3)asitliesintheconstitutiveessenceofFthatwesolveourproblem.
Soclarified,(3)ispromising,butithasanumberofunwelcomeconsequences.
Theontologicalindependenceclauseensuresthatrecursivedefinitionsarenever
realdefinitions.Supposewethinkthatnaturalnumberispriortosetoranysimilar
notionintermsofwhichafullyreductivedefinitionmightbegiven.Onemightstillbe
temptedtosay:
Tobeanaturalnumberistobeeitherzeroorthesuccessorofanaturalnumber.
Thiswouldbeuselessiftheaimweretointroduceamathematicalnovicetotheconcept,
butrealdefinitionsarenotconstrainedtobeusefulinthisway.Theclaimwouldrather
bethatasamatterofmetaphysics,whatmakeseachnaturalnumberaninstanceofthe
kindnaturalnumberisthatitiseitherzeroorthesuccessorofanumber,andthatmight
betrue.
Thisproblemcanbesolvedbydeletingtheontologicaldependenceclausein(3).
Theclausewasintroducedtoblocktrivialdefinitionsanddefinitionalcircles.Butnow
thatwehavespecifiedthatwereoperatingwithaconstitutivenotionofessence,this
maynotbenecessary.ItmaybepartoftheconsequentialessenceofFineverycase
thatx(FxFx).Butthiswillnotbepartoftheconstitutiveessence,sincethatwould
beotiose.Itislessclearwhetherthefocusonconstitutiveessenceisenoughtoblock
definitionalcirclesinwhicharelationisdefinedintermsofitsconverseandviceversa,
butsupposeitis.Thepointisthattherevisedaccountmightstilladmitrecursive
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definitionslikethedefinitionofnumbergivenaboveorthedefinitionofancestorin
termsofparent,sinceitmaywelllieintheconstitutiveessenceofancestorthatxisan
ancestorofyiffxisaparentofyortheparentofanancestorofy.
Stilltheaccountremainsproblematicforatleasttworeasons.Mostimportantly,
itwouldseemtoblockdefinitionalexpansionofacertainfamiliarandstraightforward
sort.Supposethattobeasquareistobeanequilateralrectangle,andthattobea
rectangleistobearightquadrilateral.Itshouldthenfollowthattobeasquareistobe
aright,equilateralquadrilateral.Butitishighlyunlikelythattheconstitutiveessenceof
squarecontainsbothsquaresareequilateralrectanglesandsquaresareequilateralright
quadrilaterals.Thesepropositionsbothbelongtotheconsequentialessenceofsquare.
Butifthefirstpropositionbelongstotheconstitutiveessenceofsquare,thesecond
doesnt,sincethatwouldrendertheconstitutiveessenceneedlesslyredundant.
Asafinalproblem,notethatanaccountframedintermsofconstitutiveessence
willrenderquestionsaboutthedefinablityofFsensitivetoamanifestlyintractable
question.SupposewearetemptedtosaythattobeFistobe,andunderstandthisas
theclaimthat
itliesintheconstitutiveessenceofFthatx(Fxx).
WethennotetheveryrealpossibilitythattheconstitutiveessenceofFdoesnotinclude
thissingle,universallyquantifiedbiconditional,butrathertwoquantifiedconditionals:
ItliesintheconstitutiveessenceofFthatx(Fxx)
ItliesintheconstitutiveessenceofFthatx(xFx)
Itsabsurdtothinkthatthedefinabilityof(say)primenumberturnsonwhetherthe
constitutiveessenceofprimetakesthefirstformorthesecond.Andthatsuggeststhat
theappealtoconstitutiveessencecreatesasmanyproblemsasitsolves.
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6.TheGroundTheoreticAccount
Idontknowhowtotweaktheessentialistproposaltosolvetheseproblems10,
butevenifitcanbetweaked,itwillstillfailtocaptureanimportantfeatureofreal
definition.Thefeaturehassurfacedoccasionallyinourinformalglosses.Thusin
rejectingtheinfinitelistdefinitionofprimenumber,accordingtowhichtobeaprimeis
beeither2or3or5or,wesaid:
Itisnotsothat3isprimeinvirtueofbeingeither2or3or5or;3isprimein
virtueofhaving1asitsonlyproperfactor.
Thisisobviouslyanobjectiontothelistdefinition,butwhy?Becausewetakeitfor
grantedthatrealdefinitionssupplyexplanatoryinformation.Iftobeprimeistobea
numbernwhoseonlyfactorsare1andn,itfollowsimmediatelythatwhenevernis
prime,nisprimebecausei.e.,invirtueofthefactthatitsonlyproperfactorsare1
andn.
ThisisaninstanceoftheGroundingDefinitionLink:
GDL:IfDef(F,)thennecessarily,forallx,ifxisFthenxisFinvirtueofbeing.
Theessentialistaccountsofrealdefinitionareconsistentwiththisprinciple,butthey
dontentailitorexplainit.ThereisastepfromtheclaimthatitliesinFsnaturethatF
andarecoextensivetotheclaimthatwhenathingisF,itsbeingiswhatmakesitF.
Thechallengefortheessentialististomotivatethisstep.
10Theexamplesshowthatanessentialistaccountofrealdefinitionneedsanotionof
essencethatisintermediatebetweenconsequentialessenceandconstitutiveessence.
Thenaturalthoughtistostartwiththeconstitutiveessenceandthentocloseundera
limitedsetofoperations.Thetrickistospecifytheseoperations,andIcantseehowto
dothat.
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Icantseehowtodothis,soIproposeanothertack.Theideaistotakethe
GroundingDefinitionLinkasthekeytotheanalysisofrealdefinition.Thesimplest
approachwouldbetostrengthenGDLasfollows,writingpqforthefactthatp
obtainsinvirtueofthefactthatq,orqgroundsp:
(4) Def(F,)iffx(Fx(Fxx))
Thisguarantees,asitshould,thatwhendefinesF,theFthingsarealwaysFinvirtue
ofbeing.Butitaddstheconverse:ifasamatterofnecessity,theFthingsarealwaysF
invirtueofbeing,thenthereisnothingmoretobeingFthanbeing.
Butthisisnotquiteright.Anyaccountofrealdefinitionmustensurethat
wheneverdefinesF,Fandarenecessarilycoextensive.(4)obviouslyensuresthat
whendefinesF,everyFis.11Butwithoutfurtherassumptionsitdoesnotensure
thateveryisF.
Thiswouldfollowgivenanattractivebutunderexploredprincipleinthetheory
ofground:
WeakFormality:Ifforsomepossibleobjectx,Fxx,thenforanypossible
objectx,ifxthenFxx.12
AccordingtoWeakFormality,ifsomepossiblethingisgreeninvirtueofhaving(say)
suchandsuchaspectralreflectanceprofile,thenasamatterofnecessity,anythingwith
thatprofileisgreeninvirtueofpossessingit.GivenWeakFormality,wecanreasonas
follows.Supposethatasamatterofnecessity,wheneverathingisF,itisFinvirtueof
being.LeaveasidethevacuouscaseinwhichFisimpossible.Thereisthenapossible
11SupposeDef(F,),andletabeF.Itthenfollowsimmediatelygiven(4)thataisFin
virtueofbeing,andhencegiventhefactivityofgroundthatais.12WeakFormalityisaweakeningoftheprinciplecalledFormalityinRosen(2010,p.
131.)
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FthatisFinvirtueofbeing.WeakFormalitythenensuresthateverypossiblething
isFinvirtueofbeing,whichinturnentailsgiventhefactivityofgroundthat
everypossiblethingisF.SogivenWeakFormality,(4)guaranteesthatwhen
definesF,andFarenecessarilycoextensive,asanycorrectaccountofdefinitionmust.
WeakFormality,alas,isnotselfevident.Itamountstotheclaimthatwhena
groundsFainsomeparticularcase,thecapacityofthefirstfacttogroundthesecond
derivesentirelyfromthepredicable,andnotfromthecombinationofanda.But
whyshouldnttherebecasesinwhichandatogethermakeitthecasethatFa,inpart
thankstoanditsdistinctivepowers,butalsoinpartthankstoaanditsdistinctive
powers?Idontknowanyplausiblecasesofthissort,soforwhatitsworth,Weak
Formalitystrikesmeasplausible.Butuntilitcanbegivenafirmerrationale,itwouldbe
unwisetorelyonit.
IfwedontassumeWeakFormality,(4)mustbemodifiedasfollows:
(5) Def(F,)iffx((Fxx)(Fxx))
Thisisinelegant,butitdoesthejob.ItisnowatheoremthatDef(F,)entailsx(Fx
x)).13
Irecommend(5)asthecorrectdefinitionofdefinition.14Althoughitiswritten
asabiconditional,theintendedclaimisstronger:FortodefineFjustisforittobethe
13Proof:AssumeDef(F,)andletabeanarbitrarypossibleobject.From(5)wehave
Faa(Faa).Fromthefactivityofgroundwehave(Faa)(Faa).Hence:(Fava)(Faa),whichislogicallyequivalentto(Faa).Butawasarbitrary,so:x(Fxx).14Well,almost.Theaccountbreaksdownwhenappliedtoimpossibleproperties
propertiesnothingcouldpossess.(ThankstoBrianEpsteinforpressingthispoint.)For
letFbesuchapropertye.g.,thepropertyofbeingaroundsquare,andletbeanarbitrarycomplexe.g.,xisamasslessduckwithnopossibleinstances.OuraccountimmediatelyentailsthattobeFistobe.Sincetherecantbearoundsquare
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oramasslessduck,itsautomaticthatasamatterofnecessity,anythingthingthatisa
roundasquareoramasslessduckisaroundsquareinvirtueofbeingamasslessduck.
Butthisisjusttosay,given(5),thattobearoundsquareistobeamasslessduck.
Thedraconianwaytoabsorbthepointwouldbetoinsistthatthereareno
impossibleproperties,orthatthereisonlyoneandthatitisindefinable.(Seethe
accountofpropertyindividuationin9below.)Butthatseemsadhoc.Iftherecanbe
manypropertiesnecessarilycoextensivewithgreen,whyshouldnttherebemany
propertiesnecessarilycoextensivewithroundsquare?Itwouldbebettertohavean
accountonwhichitisonethingtobearoundsquare,andanotherthingtobea
masslessduck,sinceitisanindisputablefactofmetaphysicsthatthisisso.
Theproblemarisesbecausetherearetwowaysforaclaimoftheform
(*) x((Fxx)(Fxx)
tobetrue.SuchaclaimcanbetrueinvirtueofthefactthatFandstandinsomeinterestingrelation,oritcanbetruesimplybecausenothingcouldbeeitherFor.Intuitively,isacorrectdefinitionofFonlyifthemodalizedconditionalistrueinthefirstway.Thetrickistosaythisclearly.
Hereisonewaytoimplementtheidea.Eachtruepropositioncanbeassociated
withagroundingtree,whichspecifiesthevariousclustersoffactsthatimmediately
groundit,thefactsthatimmediatelygroundthosefacts,andsoon.Apathinthe
groundingtreeforpwillstartwithpandthenproceedtoanimmediatefullgroundforp,
animmediatefullgroundforthatground,andsoon.(Utterlybasicfactswillhavetrivial
groundingtrees.Butmodalfactsoftheform(*)willneverbebasic.)Saythata
groundingtreeforsuchafactisvacuousiffeverypathinitinvolvesthefactthatFsare
impossible,orthefactthatsareimpossible,ortheequivalent.Thenwecansay:
(6)Def(F,)iff
(a)x((Fxx)(Fxx)),and
(b)Thefact(a)hasanonvacuousgroundingtree.
Thisisawayoffilteringoutspuriousdefinitionsforwhich(a)holdsonlybecauseFsare
impossible.
Imgoingtoignorethiscomplicationinwhatfollows,butforthosewhocare,(6)
istheofficialdefinitionofdefinition.
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18
casethat,asamatterofnecessity,wheneverathingisFor,itisFinvirtueofbeing.
Thismaysoundlikeanuglymouthful,butitsequivalenttoaformofwordsthatmany
philosophershavecometofindquitenatural.TosaythatdefinesF,onmyaccount,is
simplytosaythatasamatterofnecessityFsareFifandonlyif,andbecause,theyare
.15,
7.Featuresoftheproposal.
Thegroundtheoreticaccountofrealdefinitionhasanumberofappealing
features.
(a) Itexplainswhytrivialdefinitionsareexcluded.Whyaretherenocasesinwhich
Def(F,F)?BecausetherearenocasesinwhichFaFa,i.e.,becausegrounding
isirreflexive.
(b) Itexplainswhydefinitionalcirclesareexcluded.Whyaretherenocasesinwhich
arelationsRisdefinedintermsofitsconverseR*andviceversa?Becausethere
arenocasesinwhichwehavebothRabR*baandR*baRab,i.e.,because
groundingisasymmetric.
(c) Itallowsrecursivedefinitionstocountasrealdefinitions.Therecursive
definitionofancestorhasitthatforxtobeanancestorofyisforxtobeeithera
parentofyortheparentofanancestorofy.Theproposalsaysthatthisis
correctiffasamatterofnecessity,wheneverxisanancestorofythisisinvirtue
ofthefactthatxiseitheraparentofyortheparentofanancestorofy,andthat
15ThankstoSelimBerkerforpointingthisout,andforcommentsthatledtomajor
changesinthissection.
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19
mightbetrue.16Thereisnogeneralprincipleinthetheoryofgroundthatrules
itout.
(d) Itallowsthatasingleproperty,F,mayhavetwocorrectrealdefinitions,and,
providedthatwheneverathingisF,itisFbothbecauseitisandbecauseitis.
Thatthisispossibleisshownbycasesofdefinitionalexpansion.Suppose
Tobeasquareistobeanequilateralrectangle,and
Tobearectangleistobearightquadrilateral.
Theaccountentailsthataissquareinvirtueofbeinganequilateralrectangle,
andrectangularinvirtueofbeingarightquadrilateral.Andfromthese
ingredientsitcanbeshownthataisasquareinvirtueofbeinganequilateral
rightquadrilateral,hencethatsquarehasaseconddefinition:
Tobeasquareistobeanequilateralrightquadrilateral.17
Thereisnoobjectionableoverdeterminationherebecausewehaveachain:
aissquareaisanequilateralrectangleaisanequilateralright
quadrilateral,
16ThisiscertainlymoreplausiblethantheFregeandefinition,whichdefinesancestorin
termsofset.Intuitively,thefactthatMurrayRosenismyancestormightobtainandbe
groundedjustasitisevenif(perimpossibile)therewerenosets.
17Theproofinthissimplecaseisstraightforward.(Leftasanexercise.Thekeypremise
isthestrongtransitivityofground:Ifpq,andq,thenp,.(Rosen2010,p.XXX)Itshouldbepossibletoproveaprinciplethatlicensesarbitrarydefinitional
expansion:
IfDef(F,)andDef(G,),thenDef(F,/G),
where/GistheresultofsubstitutingforGin,butIhaventtried.
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20
andgroundistransitive.
Buttheremayalsobecasesinwhichtheseveraldefinitionsofasingle
propertyarenotrelatedinthissimpleway.Itissometimessaid,forexample,
thatprimenumberhastwodefinitions:thegradeschooldefinition,accordingto
whichtobeaprimeistobeanumbernwhoseonlyfactorsare1andn,anda
moreadvanceddefinitionaccordingtowhichtobeprimeistobeanumbern
suchthatwheneverndividesaproductpq,ndivideseitherporq(Tappenden
1998).Thepresentaccountallowsthatthesemaybothbecorrectreal
definitionsofasingleproperty,providedwearepreparedtosaythatwhenever
nisprime,itisprimebothbecauseitsatisfiesthefirstcondition,andbecauseit
satisfiesthesecond.
(e) Finally,theproposalshedslightonwhywemightcareaboutrealdefinitionsin
philosophy.WhyshoulditbeusefulorinterestingtoknowwhatitistobeF?
BecausesuchknowledgeputsusinapositiontoexplainwhyanygivenFisF,and
explanatoryinformationisalwaysworthhaving.
9.TheIndividuationofproperties
Theargumentsagainstthesimplemodalaccountofdefinitionsuggestthatwe
areoperatingwithahyperintensionalconceptionofpropertiesonwhichitisonething
tobegreen,andsomethingquitedifferenttobegrueandobservedorbleenand
unobserved.Anditisalwaysafairchallengetoanysuchaccounttoaskforclarification
ofthisconception,arequestthatissometimesputasthedemandfortheidentity
conditionsofpropertiesandrelations.SupposewehavepropertiesFandGpickedout
bydifferentbitsoflanguageorbydifferentconcepts.Theintensionalistsaystheyare
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21
thesamepropertyifftheyaretheynecessarilycoextensive.Whatdoesthe
hyperintensionalistsay?
Perhapsjustthis:IfFandGindefinable,theyarethesamepropertyifftheyare
necessarilycoextensive;iftheyredefinable,theyareidenticalifftheyhavethesame
definitions:
PropertyIdentity:FandGarethesamepropertyiff
(a) FandGareindefinableandx(FxGx),or
(b) FandGaredefinableandforall,(Def(F)Def(G,))
(Ihaventdefendedtheaccountforindefinableproperties,butImawareofnoground
fordistinguishingcointensiveindefinablepropertiesthatwouldnotalsobegroundsfor
distinguishingHesperusandPhosphorus.)Giventhegroundtheoreticaccountof
definition,thisamountstosayingthatdefinablepropertiesareindividuatedbythe
groundsforatomicfactsinvolvingthem.WhenFandGaredefinable,F=Giffinevery
possiblecase,thegroundsforFaarealsogroundsforGaandviceversa.
IftherecanbecasesinwhichFandGarenecessarilycoextensiveandyetthe
groundsforFadifferfromthegroundsforGa,thisaccountwillentailahyperintensional
conceptionofproperties.Butthatturnsouttobeasubstantialif.Strictlyspeaking,
myaccountofdefinitionisconsistentwithanorthodoxintensionalviewofproperties.
Thismaynotbeobvious,sothepointisworthexploring.
IhavecertainlyassumedandoccasionallyarguedthatDef(F,)is
hyperintensional.Thecounterexamplestothesimplemodalaccountallgotoshowthis.
ButthecounterexamplesareallcasesinwhichwehaveDef(F,)andx(xx)
butnotDef(F,).Thatis,theywereallcasesinwhichDef(F,)ishyperintensionalon
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22
theright.Theaccountexplainsthishyperintensionalitybyreducingittothe
hyperintensionalityofground.Butallofthisisperfectlyconsistentwiththeassumption
thatDef(F,)issimplyintensionalontheleft,orinotherwords,thatDef(F,)and
x(FxGx)entailDef(G,).
Toseewhy,recallasubtlepointstipulatedattheoutset,namely,thatdefinition
istobeunderstoodasarelationbetweenapropertyandacomplex.Propertiesand
complexesarealikeinthisrespect:bothcombinewithanobject(orasequenceobjects)
toyieldaproposition.Thedifferenceisthatcomplexesarepropositionlikeitemswith
internalstructureopensentencesinaworldlylanguagewhereaspropertiesare
(forallwecare)mereologicallysimple.Thereisthusadifferencebetweenthecomplex
xisgrueandobservedorbleenandunobserved,
whichhasgrue,bleen,observedandvariouslogicalparticlesasconstituents,and
thepropertyofbeinggrueandobservedorbleenandunobserved,
whichdoesnot.Inthisframeworkweshouldthinkofthepropertyofbeing
sometimesregimentedasxxasanoperatorthatattachestoacomplexto
yieldatermthatpicksoutaproperty:xx.Theargumentsforthefunctionare
typicallycomplex;thevaluesofthatfunctionthepropertiesarenot.
ToseethattheviewIvebeendevelopingisconsistentwithintensionalismabout
properties,assumeintensionalismandconsiderthefollowingpackageofclaimsabout
green:
(a) Asamatterofnecessity,athingisgreeniffitisgrueandobservedorbleenand
unobserved.
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23
(b) Sothepropertyofbeinggreen=thepropertyofbeinggrueandobservedor
bleenandunobserved.
(c) ButitisnotthecasethatDef(green,xisgrueandobservedorbleenand
unobserved).
Givenouraccountofdefinition,thispackageentailstheplausibleclaimthat
(d) Thereisapossiblecaseinwhichathingisgreen,butnotinvirtueofbeinggrue
andobservedorbleenandunobserved.
Butitalsoentailsthesomewhatsurprisingclaimthat
(e) Thereisapossiblecaseinwhichathingpossessesthepropertyofbeinggrue
andobservedorbleenandunobserved,butnotinvirtueofbeinggrueand
observedorbleenandunobserved.
Thisisaclaimoftheform:
Possibly,x(x)a,butnot:x(x)aa
Anditmaybehardtoseehowanysuchclaimcouldbetrue.Butanintensionalistwho
acceptsthegroundingidiomneednotfindthispuzzlingatall.Shecansay:
Thefunctionxtakesfromacomplexxtotheuniquepropertyintensionally
equivalenttox(whenthereisone),muchasthedefinitedescriptionoperator
takesusfromacomplextotheuniquesatisfierofthatcomplex(whenthereis
one).Inthiscase,thepropertyinquestionthepropertyofbeinggrueand
observedorbleenandunobservedjustisthepropertyofbeinggreen.(They
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mustbethesameproperty,sincetheyreintensionallyequivalent.)Thisproperty
mayormaynothaveadefinition.Butitsdefinitioncantbereadofffromthe
structureofanarbitraryexpressionthatpicksitout,justastheessenceofthe
inventorofbifocalscannotbereadofffromthestructureofanarbitrarydefinite
descriptionthatpickshimout.Ingeneral,from
aisF,and
F=thepropertyofbeing,
itdoesnotfollowthat
aisFinvirtueofbeing.
WhetherthislastclaimistrueistruedependsonthedefinitionofF(aka,the
propertyofbeing),whichisupforgrabs.
Onthisversionofintensionalism,propertiesarelikeobjectsinthisrespect:theycanbe
pickedoutornamedinindefinitelymanyways,mostofwhichwillfailtoencodetheir
definitions.ThisisafamiliarpointifwethinkofdescriptionslikeFredsfavorite
property.Itislessfamiliarwhenthetermsinquestionareoftheformthepropertyof
being.Stillitisacoherentview,andthefactthatitiscoherentservestoshowthat
theconceptionofrealdefinitionthatIvebeenadvancingis,perhapssomewhat
surprisingly,fullyconsistentwithanintensionalistviewofproperties.
Wearepushedtoahyperintensionalviewofpropertiesonlyifwetakeon
additionalcommitments.ConsiderthethesisthatmightbecalledStrongProperty
Abstraction(SPA):
SPA:Foranycomplex,thereisapropertyFsuchthatDef(F,)
Thisismuchstrongerthanordinarypropertyabstraction(whichmaybetoostrong
alreadygiventhethreatofparadox).Ordinarypropertyabstractiontellsusthatforany
complex,thereisapropertyintensionallyequivalentto:xx.Thisnewprinciple
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25
tellsusthatforanycomplex,thereisapropertydefinedby,thatis,aproperty
atomicfactsinvolvingwhicharesystematicallygroundedinfactsoftheforma.A
principleofthissortwouldguaranteetheexistenceofapropertyFsuchthattobeFis
tobegrueandobservedorbleenandunobserved.Andifthereissuchaproperty,
intensionalismisfalse,sincethatpropertyisdistinctfromgreenbutnecessarily
coextensivewithit.Butintheabsenceofsomesuchprinciple,itisconsistenttosay
thateverypropertyequivalenttogreenhasthesamedefinitionandisthusidenticalto
green.
WhatisthestatusofSPA?Ifindithardtosay.Iseenoobjectiontothe
hyperintensionalconceptionofproperties,andoftenfinditnatural.Itstrikesmeas
obvious,forexample,thatthepropertyofbeingasquarenumberisdistinctfromthe
propertyofbeingasumofconsecutiveoddnumbersstartingwithone,andthatthisis
shownbythefactthatyoupossessthefirstpropertyinvirtuebeingsomeonessquare,
andthesecondpropertyforanaltogetherdifferentreason.Butanyconsiderationthat
wouldclinchthecaseagainstintensionalisminthisframeworkwouldbehighly
theoreticalandrecherchinsofarasitgoesbeyondthissortofintuition.Theaccount
ofdefinitionIhavegivenisfitsquitenicelywithahyperintensionalviewofproperties,
sinceitgivesthehyperintensionalistsomethingcleartosayinresponsetothedemand
foranaccountofpropertyindividuation.Thepointoftheargumentjustrehearsedisto
showthatevenifwerejecttheintuitionsthatsupportthehyperintensionalview,we
canstillaccepttheaccountofpropertyindividuationsketchedaboveandthe
conceptionofrealdefinitionitpresupposes.
10.Anapplication:Interpretingthedebateovermoralnaturalism.
Toseewhythismightmatter,supposethatafterthedusthassettledinfirst
orderethics,wefindourselveswithacounterexampleproofequivalenceoftheform:
(N) Necessarily,anactismorallypermissibleiffitis,
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26
whereisathoroughlynaturalisticcomplexcomposedofindisputablynonnormative
bitsandpieces:cause,pleasure,etc.Fortheorthodoxintensionalistwhoeschewsfine
grainednotionsofgroundinganddefinition,thisamountstonaturalismaboutmoral
permissibilityonanyplausibleunderstandingofthatthesis,sinceitentailsthatmoral
permissibilityisidenticalwiththepropertyofbeing,whichisclearlyanaturalproperty
byconstruction.18
Inmyframework,bycontrast,(N)isconsistentbothwithnaturalismandwith
nonnaturalismaboutpermissibility.Supposewetakenaturalismtobethethesisthat
everymoralpropertyisanaturalproperty,whereapropertycountsasnaturaliffitis
eitheraprimitivenonnormativepropertyorapropertythatcanbedefined,inour
sense,innonnormativeterms.19(N)isthenconsistentwithnaturalismaboutmoral
permissibility(MP)becauseitsconsistentwithDef(MP,).Thatis,(N)isconsistent
withtheclaimthatwhenanactispermissible,itispermissibleifandonlyif,and
because,itis.But(N)isalsoconsistentwiththedenialofthisclaim.Consider,for
example,thenonnaturalistwhosays:
18Indeed,sincethestrongsupervenienceofthenormativeonthenonnormative
guaranteestheexistenceofatruthoftheform(N)foreachnormativeproperty,an
orthodoxintensionalistwhoacceptsstrongsupervenienceasalmosteveryonedoes
mustbeamoralnaturalistacrosstheboard.
19Thisisaplausibleaccountofwhatissometimescalledreductivenaturalismin
metaethics,aviewthatissupposedtocontrastbothwithnonnaturalismandalsowith
somethingcallednonreductivenaturalism.Iconfesstobeingunabletomakesenseof
thelattercontrast.Wecouldidentifynonreductivenaturalismabout(say)moral
permissibilitywiththeviewthatwhilethefactsaboutmoralpermissibilitysuperveneon
thenonnormativefacts,thereisnononnormativeconditionsuchthatDef(MP,).Butifthatstheview,thenmostselfproclaimednonnaturalistsParfit,Enochand
Scanlon,forexampleareinfactnonreductivenaturalists,andtheonlynonnaturalist
onthecontemporarysceneisKitFine(2000),whorejectsthemetaphysical
supervenienceofthenormativeonthenonnormative.Thatsuggeststhatthisaccount
ofnonreductivenaturalismcantberight;butifthatsnottheview,thenIdontknow
whattheviewissupposedtobe.
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27
Iagreethatanactismorallypermissibleifandonlyifitis.Butwhenweask
whyanygivenactismorallypermissible,theansweralwayslookslikethis:Ais
permissibleinvirtueofthefactthatAistogetherwithasubstantivemorallaw
accordingtowhichanactispermissibleifandonlyifitis.
Thisviewaccepts(N)butdeniesDef(MP,)andeverysimilarclaim,andsoconstitutes
agenuinealternativetonaturalism.20
Thisframeworkhastheadvantageofsharpeningthedebateovermoral
naturalisminawaythatmakesitclearwhythedebatehasbeensohardtoresolve.
Thequestionisnotwhethermoralpredicates(orproperties)arenecessarilycoextensive
withnonnormativeconditions,astheymustbegivensupervenience,whichnearly
everyoneaccepts.Nororisitwhethermoralpropertiesareidenticalwithnatural
propertiesonthesimpleintensionalistconceptionofproperties,sinceagain,thatsa
trivialconsequenceofsupervenience.Thequestionisratherwhethermoralproperties
admitofnaturalisticdefinition,orequivalently,whethertheatomicmoralfactsare
systematicallygroundedinnonnormativefacts.ThenaturalistsaysthatwhenAis
permissible,itispermissiblesimplyinvirtueofsatisfyingsomenaturalisticcondition.
Thenonnaturalistdeniesthis,maintainingthatwhenAispermissible,thisfactis
20Toillustratethepointmadeinthelastsection,itsworthnotingthatthisnon
naturalistviewcomesintwoflavors.Themoststraightforwardversionofitis
hyperintensionalist.Onthisview,therearetwopropertiesnecessarilycoextensivewith
:moralpermissibility,whichisnonnatural,andthepropertyofbeing,whichadmitsofasimplenaturalisticdefinition:Def(xx,)Butthereisalsoanintensionalistversionofnonnaturalism.Onthisview,weidentifymoralpermissibilitywiththe
propertyofbeing(sincetheyarecointensive),butinsistthatthispropertycannotbedefinedinnaturalisticterms.InparticularwedenyDef(xx,),rejectingStrongPropertyAbstractioninthiscase.Icanthinkofnogoodreasontoacceptthisview,or
totakeitseriouslyasapossibilityinmetaethics.Imentionitonlytoshowthatan
intensionalistwhoacceptsafinegrainednotionofgroundanddefinitioncanbeanon
naturalistinethicsevenifshebelievesthateverymoralpropertyisequivalenttoa
naturalisticcondition.
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28
groundedinnaturalfactstogetherwithasubstantive,syntheticmoralprinciple.21This
issueismanifestlyarcane.Somequestionsaboutwhatgroundswhatareeasy,butthis
oneisnt.Ifthisiswhatthedebateovernaturalisminethicsboilsdownto,itshould
comeasnosurprisethatwehavenomanagedtoresolveit.
10.Conclusion
Philosophyisuniqueamongdisciplinesintakingfullresponsibilityforitsjargon.
Itsnotthemathematiciansjobtosaywhatanumberis.Itsnotthephysicistsjobto
saywhattimeis.Butwhenaphilosopheremploysanidiomforaseriouspurpose,itis
automaticallyherjob,atsomepoint,tosaywhatcanbesaidbywayofexplanation.As
wehavenoted,everypartofanalyticphilosophyisinthebusinessofgivingaccounts
ordefinitionsoranalyses.Andsoitfallstoustosaywhatweredoingwhenwedo
this.
Ihavesupposedthattheobjectsofanalysisarepropertiesandrelations,andIve
givena thoroughly metaphysicalaccountofwhatdefinitioncomes to. According to
that account, to define a property is to identify a necessary truth that specifies, in a
uniform way, how atomic facts involving that property are grounded in more
fundamentalfacts.
Myaccount employsonemoderately exotic primitive: anotionof ground that
seems tome to be needed anyway and forwhich detailed theories have been given
elsewhere.22Itwouldbegoodifwecoulddowithoutit,butIdontseehowthiscanbe
done,andsoIofferthefollowingconjecture.Theidiomsofdefinitionandanalysisthat
wetakeforgrantedinphilosophystandorfallwiththegroundingidiom,sincethereis
nowaytoexplainthemwithoutit.Ifyoureallergictoground,youshouldstopasking
what it is foracreaturetobeconsciousor fora fact tobea lawofnatureor fortwo
21Oralternatively,thattheatomicmoralfactshavenofullgrounds,beingatbestpartly
groundedintheparticularnaturalfactsthatunderliethem.Thisisanoptionforradical
particularists,forwhomgeneralmorallawsplaynoexplanatoryrole.22SeeCorreiaandSchnieder(2012)forthestateoftheart(asof2012).
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expressionstohavethesamemeaningorforanacttobefreeorforanartifacttobean
artwork,sinceyoucantexplainwhatyourquestionsmeanwithoutinvokingaconcept
youreject.Ontheotherhand,ifyouthinkthesequestionsmakegoodsense,thenyou
shouldmakeyourpeacewithgrounding,sinceyouarecommittedtomakingsenseofit
bythequestionsyoumakeityourbusinesstoaskandanswer.