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1、Half-Truths and the LiarIntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsBackground:Half-truthsEngel 2016,Egr&Icard 2018 a.o.IA half-truth can be defined as a sentence that fails to tell thewhole truth(in violation of Grices maxim of Quantity),or as asentence that is true in one(relevant)sen
2、se,but false inanother(in violation of Grices maxim of Quality)IBoth failures often co-occur,both are related to someconnection between utterances and information queries.2/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsBackground:Half-truthsEngel 2016,Egr&Icard 2018 a.o.IA half-truth ca
3、n be defined as a sentence that fails to tell thewhole truth(in violation of Grices maxim of Quantity),or as asentence that is true in one(relevant)sense,but false inanother(in violation of Grices maxim of Quality)IBoth failures often co-occur,both are related to someconnection between utterances an
4、d information queries.2/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsNot a half-truth:a clear lie“I do not have,Mr.Deputee,I never had,a foreign bankaccount,neither now,nor before”(J.Cahuzac,December 5 2012,response to DanielFlasquelle)3/54IntroductionStrict-TolerantAbsolute Adjectives
5、Half-truthsAn example of a half-truthAugustine,De Mendacio;Stokke 2018Abraham is asked by King Abimelech whether Sarah is his wife(Gen.20.3).(1)Sarah is my sister.ITrue:because Sarah is Abrahams half-sister(fathersdaughter).IFalse:because Sarah is not just his sister,she is also his wife.Analysis 1:
6、perfectly true sentence,with a false implicature.Analysis 2:half-true sentence,the sentence is equivocal,true inone sense(“half-sister”)false in another(“full sister”)4/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsAn example of a half-truthAugustine,De Mendacio;Stokke 2018Abraham is as
7、ked by King Abimelech whether Sarah is his wife(Gen.20.3).(1)Sarah is my sister.ITrue:because Sarah is Abrahams half-sister(fathersdaughter).IFalse:because Sarah is not just his sister,she is also his wife.Analysis 1:perfectly true sentence,with a false implicature.Analysis 2:half-true sentence,the
8、sentence is equivocal,true inone sense(“half-sister”)false in another(“full sister”)4/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsAn example of a half-truthAugustine,De Mendacio;Stokke 2018Abraham is asked by King Abimelech whether Sarah is his wife(Gen.20.3).(1)Sarah is my sister.ITr
9、ue:because Sarah is Abrahams half-sister(fathersdaughter).IFalse:because Sarah is not just his sister,she is also his wife.Analysis 1:perfectly true sentence,with a false implicature.Analysis 2:half-true sentence,the sentence is equivocal,true inone sense(“half-sister”)false in another(“full sister”
10、)4/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsLie or Truth?The Clinton Case(2)I have never had sexual relations with Monica Lewinsky.(3)If she told someone that she had a sexual affair with youbeginning in November of 1995,would that be a lie?Its certainly not the truth.It would not
11、be the truth.5/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsLie or Truth?The Clinton Case(2)I have never had sexual relations with Monica Lewinsky.(3)If she told someone that she had a sexual affair with youbeginning in November of 1995,would that be a lie?Its certainly not the truth.I
12、t would not be the truth.5/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsLie or Truth?The Clinton Case(2)I have never had sexual relations with Monica Lewinsky.(3)If she told someone that she had a sexual affair with youbeginning in November of 1995,would that be a lie?Its certainly not
13、 the truth.It would not be the truth.5/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsFalse vs.Not TrueNote that Clinton does not say“it is false”,but prefers to say“it isnot true”.IOnly implicates that the claim is false by saying“it is not true”IAnother interpretation is:the claim cont
14、ains a grain of truth,but it is not“the whole truth”.6/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsFalse vs.Not TrueNote that Clinton does not say“it is false”,but prefers to say“it isnot true”.IOnly implicates that the claim is false by saying“it is not true”IAnother interpretation i
15、s:the claim contains a grain of truth,but it is not“the whole truth”.6/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsPrecisificationsBasic strategy:there is a precisification of“sexual affair/relations”(same for“sister”)on which the claim is false.There is also one onwhich it is true.IB
16、ut given the former,the claim is not perfectly true.IThere is even a sense in which,if only the bad(good)precisification is relevant,the claim is perfectly false(perfectlytrue).7/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsPrecisifying“sexual relations”(4)“Have you ever had sexual rel
17、ations with Monica Lewinsky,as that term is defined in Deposition Exhibit 1?”(5)“No,I thought the definition of sexual relations includedany activity by the person being deposed,where the personwas the actor and came in contact with those parts of thebodies with the purpose or intent of gratificatio
18、n,andexcluded any other activity”.cf.Tiersma,P.(2004).Did Clinton lie:Defining sexual relations.Chicago-Kent Law Review,79(3).8/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsPrecisifying“sexual relations”(4)“Have you ever had sexual relations with Monica Lewinsky,as that term is defined
19、 in Deposition Exhibit 1?”(5)“No,I thought the definition of sexual relations includedany activity by the person being deposed,where the personwas the actor and came in contact with those parts of thebodies with the purpose or intent of gratification,andexcluded any other activity”.cf.Tiersma,P.(200
20、4).Did Clinton lie:Defining sexual relations.Chicago-Kent Law Review,79(3).8/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsA more abstract case:The Liar“This sentence is not true”:is not true.True or False?9/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsProposalIFrom LP per
21、spective:Liar is(perfectly)true and(perfectly)false.IArgument here:from ST perspective,the Liar ought to be ahalf-truth,hence not perfectly true.ISTEP 1:revisit ST account of the Liar(CERvR 2013)ISTEP 2:argue that pace Haack 1980,“true”is gradable(albeit in limited sense,see also Henderson 2019)10/5
22、4IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsProposalIFrom LP perspective:Liar is(perfectly)true and(perfectly)false.IArgument here:from ST perspective,the Liar ought to be ahalf-truth,hence not perfectly true.ISTEP 1:revisit ST account of the Liar(CERvR 2013)ISTEP 2:argue that pace Haa
23、ck 1980,“true”is gradable(albeit in limited sense,see also Henderson 2019)10/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsProposalIFrom LP perspective:Liar is(perfectly)true and(perfectly)false.IArgument here:from ST perspective,the Liar ought to be ahalf-truth,hence not perfectly true
24、.ISTEP 1:revisit ST account of the Liar(CERvR 2013)ISTEP 2:argue that pace Haack 1980,“true”is gradable(albeit in limited sense,see also Henderson 2019)10/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsProposalIFrom LP perspective:Liar is(perfectly)true and(perfectly)false.IArgument here
25、:from ST perspective,the Liar ought to be ahalf-truth,hence not perfectly true.ISTEP 1:revisit ST account of the Liar(CERvR 2013)ISTEP 2:argue that pace Haack 1980,“true”is gradable(albeit in limited sense,see also Henderson 2019)10/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsIntroduc
26、tionStrict-TolerantAbsolute AdjectivesHalf-truths11/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsThe strict-tolerant account of vaguenessCobreros et al.2012Basic idea:all lexically vague predicates can be used in a stronger(strict)or a weaker sense(tolerant).Two explanatory benefits:Ia
27、n account of the sorites paradoxIan account of borderline status for vague predicates12/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsThe TCS accountEvery predicate P is interpreted relative to a classical model M anda similarity relation Pthat is reflexive and symmetric,but may failto
28、be transitive.IM|=tPa iffb(a Pb&M|=cPb)IM|=sPa iffb(a Pb M|=cPb)13/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsThe TCS pictureCounter instancesBorderline casesInstancesClassicalTallNot tallStrictTallNot tallTolerantTallNot tall14/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-tr
29、uthsThe soritesIf x is tall and y is imperceptibly different from x in height,then yis tall.Px x Py PyThe principle is tolerantly valid,for really it amounts to:If M|=sPa,and a Pb,then M|=tPb15/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsThe strict-tolerant account of the LiarRipley 2
30、012,Cobreros et al.2013 TrhiISentences can take one of the three values 0,12,1.IKripke-Kleene semantics for compound sentencesIM|=t iffM()12IM|=s iffM()=1IST-consequence:whenever the premises are s-true,theconclusion is t-true.ICoincides with CL on first-order languageIK3 on premisses,LP on conclusi
31、ons16/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsThe strict-tolerant account of the LiarRipley 2012,Cobreros et al.2013 TrhiISentences can take one of the three values 0,12,1.IKripke-Kleene semantics for compound sentencesIM|=t iffM()12IM|=s iffM()=1IST-consequence:whenever the premi
32、ses are s-true,theconclusion is t-true.ICoincides with CL on first-order languageIK3 on premisses,LP on conclusions16/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsThe strict-tolerant account of the LiarRipley 2012,Cobreros et al.2013 TrhiISentences can take one of the three values 0,12
33、,1.IKripke-Kleene semantics for compound sentencesIM|=t iffM()12IM|=s iffM()=1IST-consequence:whenever the premises are s-true,theconclusion is t-true.ICoincides with CL on first-order languageIK3 on premisses,LP on conclusions16/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsThe strict-
34、tolerant account of the LiarRipley 2012,Cobreros et al.2013 TrhiISentences can take one of the three values 0,12,1.IKripke-Kleene semantics for compound sentencesIM|=t iffM()12IM|=s iffM()=1IST-consequence:whenever the premises are s-true,theconclusion is t-true.ICoincides with CL on first-order lan
35、guageIK3 on premisses,LP on conclusions16/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsThe strict-tolerant account of the LiarRipley 2012,Cobreros et al.2013 TrhiISentences can take one of the three values 0,12,1.IKripke-Kleene semantics for compound sentencesIM|=t iffM()12IM|=s iffM()
36、=1IST-consequence:whenever the premises are s-true,theconclusion is t-true.ICoincides with CL on first-order languageIK3 on premisses,LP on conclusions16/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsAn ST-approach to the LiarI can only take the value12if M(Trhi)=M()IHence:|=ST+,|=ST+,b
37、ut 6|=ST+IST+-consequence preserves a very simple and well-behavedconditional,but is nontransitive.17/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsAn ST-approach to the LiarI can only take the value12if M(Trhi)=M()IHence:|=ST+,|=ST+,but 6|=ST+IST+-consequence preserves a very simple an
38、d well-behavedconditional,but is nontransitive.17/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsTruth and assertionCobreros et al.2013,2015In previous work,the parallel between the ST account of vaguenessand the ST account of the semantic paradoxes was emphasized.However,the parallel wa
39、s breached in a way:IFor vagueness:it was admitted that semantically,vaguepredicates can be interpreted strictly or tolerantlyIFor truth:the view was that truth is a unitary notion,onlygoverned by the disquotation principle,but that assertioncomes in degrees:strict and tolerant18/54IntroductionStric
40、t-TolerantAbsolute AdjectivesHalf-truthsTruth and assertionCobreros et al.2013,2015In previous work,the parallel between the ST account of vaguenessand the ST account of the semantic paradoxes was emphasized.However,the parallel was breached in a way:IFor vagueness:it was admitted that semantically,
41、vaguepredicates can be interpreted strictly or tolerantlyIFor truth:the view was that truth is a unitary notion,onlygoverned by the disquotation principle,but that assertioncomes in degrees:strict and tolerant18/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsForce vs ContentRipley 2013,C
42、obreros et al.2013“As far as we can see,then,there are at least two ways tounderstand the status paradoxical sentences have on anST+-based theory(.).Both ways take paradoxicalsentences to fall in between strict and tolerant,but oneway takes the distinction between strict and tolerant tobe a pragmati
43、c distinction,and the other to be adistinction in meaning.”19/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsProblem and main claimThe problem with the assertion-oriented theory is that the parallelbetween the two accounts appears somewhat like a coincidence.We get a tighter link,on the
44、other hand,if we assume that“true”isa vague predicate,susceptible to the kind of meaning ambiguityclaimed for vague predicates quite generally(this meaningambiguity also interacts with use)20/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsProblem and main claimThe problem with the assert
45、ion-oriented theory is that the parallelbetween the two accounts appears somewhat like a coincidence.We get a tighter link,on the other hand,if we assume that“true”isa vague predicate,susceptible to the kind of meaning ambiguityclaimed for vague predicates quite generally(this meaningambiguity also
46、interacts with use)20/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsTrue as vagueCounter instancesBorderline casesInstancesClassicalTrueNot TrueStrictTrueNot TrueTolerantTrueNot True21/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsBackground to this paper2019 Festschrift fo
47、r G.Priest,C.Baskent and T.Ferguson eds.Claim there:true contradictions of the form“x is P and not P”depend on P being vague,and on an underlying analysis of theform“x is P in some respects/to some degree,but not P in allrespects/to all degrees”.Priests response:“it it is not clear that the truth pr
48、edicate is avague predicate”22/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsBackground to this paper2019 Festschrift for G.Priest,C.Baskent and T.Ferguson eds.Claim there:true contradictions of the form“x is P and not P”depend on P being vague,and on an underlying analysis of theform“x
49、 is P in some respects/to some degree,but not P in allrespects/to all degrees”.Priests response:“it it is not clear that the truth predicate is avague predicate”22/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsAbout vaguenessIAn element of disagreement(with G.Priest,with others likely)i
50、s that I take the admission of borderline cases to be anecessary and sufficient condition for vagueness.ISorites-susceptibility is only a sufficient conditionIThe Liar is a borderline case of a true/false sentence23/54IntroductionStrict-TolerantAbsolute AdjectivesHalf-truthsAbout vaguenessIAn elemen