Synthese Library 452 Studies in Epistemology, Logic, Methodology, and Philosophy of Science Alessio Santelli   Editor Ockhamism and Philosophy of Time Semantic and Metaphysical Issues Concerning Future Contingents Synthese Library Studies in Epistemology, Logic, Methodology, and Philosophy of Science Volume 452 Editor-in-Chief OtávioBueno,DepartmentofPhilosophy,UniversityofMiami,CoralGables,USA EditorialBoardMembers BeritBrogaard,UniversityofMiami,CoralGables,USA AnjanChakravartty,DepartmentofPhilosophy,UniversityofMiami,CoralGables, USA StevenFrench,UniversityofLeeds,Leeds,UK CatarinaDutilhNovaes,VUAmsterdam,Amsterdam,TheNetherlands DarrellP.Rowbottom,DepartmentofPhilosophy,LingnanUniversity,TuenMun, HongKong EmmaRuttkamp,DepartmentofPhilosophy,UniversityofSouthAfrica,Pretoria, SouthAfrica KristieMiller,DepartmentofPhilosophy,Centrefortime,UniversityofSydney, Sydney,Australia The aim of Synthese Library is to provide a forum for the best current work in themethodologyandphilosophyofscienceandinepistemology,allbroadlyunder- stood.Awidevarietyofdifferentapproacheshavetraditionallybeenrepresentedin theLibrary,andeveryeffortis madetomaintainthisvariety,notforits ownsake, butbecausewebelievethattherearemanyfruitfulandilluminatingapproachesto thephilosophyofscienceandrelateddisciplines. Specialattentionispaidtomethodologicalstudieswhichillustratetheinterplay of empirical and philosophical viewpoints and to contributions to the formal (logical,set-theoretical,mathematical,information-theoretical,decision-theoretical, etc.) methodology of empirical sciences. Likewise, the applications of logical methodstoepistemologyaswellasphilosophicallyandmethodologicallyrelevant studiesinlogicarestronglyencouraged.Theemphasisonlogicwillbetemperedby interestinthepsychological,historical,andsociologicalaspectsofscience. In addition to monographs Synthese Library publishes thematically unified anthologies and edited volumes with a well-defined topical focus inside the aim and scope of the book series. The contributions in the volumes are expected to befocusedandstructurallyorganizedinaccordancewiththecentraltheme(s),and shouldbetiedtogetherbyanextensiveeditorialintroductionorsetofintroductions if the volume is divided into parts. An extensive bibliography and index are mandatory. Moreinformationaboutthisseriesathttps://link.springer.com/bookseries/6607 Alessio Santelli Editor Ockhamism and Philosophy of Time Semantic and Metaphysical Issues Concerning Future Contingents Editor AlessioSantelli UniversityofL’Aquila L’Aquila,Italy ISSN0166-6991 ISSN2542-8292 (electronic) SyntheseLibrary ISBN978-3-030-90358-9 ISBN978-3-030-90359-6 (eBook) https://doi.org/10.1007/978-3-030-90359-6 ©SpringerNatureSwitzerlandAG2022 Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpartof thematerialisconcerned,specificallytherightsoftranslation,reprinting,reuseofillustrations,recitation, broadcasting,reproductiononmicrofilmsorinanyotherphysicalway,andtransmissionorinformation storageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilarmethodology nowknownorhereafterdeveloped. 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Theregisteredcompanyaddressis:Gewerbestrasse11,6330Cham,Switzerland Preface The present volume aims to critically assess Ockhamism, a theory according to whichfuturecontingentsaretrueorfalse,withoutbeingneitherdeterminatelytrue nordeterminatelyfalse.OckhamismsounderstoodisopposedtoAristotelianism– atheorythatgoesbackatleasttoAristotle–accordingtowhich,inordertosecure the contingencyof the future,future contingentsmust be deemed neither true nor false.Overthepastfewyears,Ockhamismhasreceivedsignificantattentionamong scholars. This has generated an intensive debate whose primary interest was to exploreOckhamism’ssemanticandmetaphysicalimplications.Thisvolumeintends to introduce the reader to such a debate, and also to investigate several important issuesthatarestillinneedoffurtherarticulationandclarification. Almost all the chapters it contains were presented at “Ockhamism and Philos- ophy of Time,” an international workshop funded by the project “Dipartimento di Eccellenza 2018/2022 – Arti, Linguaggi e Media: tradurre e transcodificare,” and held in the Department of Human Studies at the University of L’Aquila in September2018.Myhopeis thattheywillcontributeto pushforwardand further clarifythecomplexandlivelydebateaboutOckhamism,especiallyinrelationtothe semanticandmetaphysicalissuesconcerningoneofthecentraltopicsofphilosophy, namely that of future contingency. For this, I would like to thank the authors for their insightful and invaluable papers, the reviewers for their precious work, and the editors of Springer for their patience. Many thanks to Simone Gozzano for supporting this project from the beginning, and to Giorgio Mazzullo who read a previous version of my article and contributed to amending many mistakes. A special thank you goes to Andrea Iacona for his generous advice and helpful conversationsduringthislastyearofwork.Lastbutnotleast,Iwouldliketothank GiorgioLandowhohelpedmetoorganizetheworkshop.Hisprecioussuggestions, withoutadoubt,sparedmealotofunnecessarywork. L’Aquila,Italy AlessioSantelli v Contents 1 FromWilliamofOckhamtoContemporaryOckhamism andBackAgain:AnOverview ............................................. 1 AlessioSantelli 2 OckhamonTime............................................................. 11 CeciliaTrifogli 3 OckhamisticInspirationinModernTense-Logic ........................ 33 PeterØhrstrømandDavidJakobsen 4 OckhamismWithoutMolinism............................................. 55 JacekWawer 5 FutureContingentsinaBranchingUniverse............................. 73 MitchellS.Green 6 ATooThinTrueFuture:TheProblemofGroundingWithin PresentistTRLSemantics................................................... 93 CiroDe FlorioandAldoFrigerio 7 Presentism,Ockhamism,andTruth-Grounding ......................... 117 FabriceCorreiaandSvenRosenkranz 8 TheMetaphysicsofOckhamism ........................................... 131 AndreaIacona 9 TheMetaphysicsofPassageinDynamicalReductionModels ofQuantumMechanics...................................................... 147 CristianMarianiandGiulianoTorrengo vii About the Editor Alessio Santelli Completed his PhD at Ca’ Foscari, University of Venice. He carriedoutresearchactivitiesatLOGOS,UniversityofBarcelona(UB),andatthe UniversityofL’Aquila.Hismaininterestsareinsemantics,temporallogic,andin philosophyoftime,withaparticularfocusontheproblemoffuturecontingents. ix Chapter 1 From Williamof Ockham toContemporary Ockhamismand Back Again: An Overview AlessioSantelli Abstract Ockhamism’smaintenetisthatfuturecontingentsareeithertrueorfalse, eveniftheyareneitherdeterminatelytruenordeterminatelyfalse.Itisinspiredby someideasofWilliamofOckham,andinparticularbyhissolutiontotheproblemof futurecontingents.Inthemodernbranchingtimesetting,Ockhamismisfrequently associatedwiththeso-calledThinRedLine,aviewaccordingtowhichamongthe many possible futures only one is the actual future – namely, the one that will be realized. Despite its apparent simplicity, however, there is still no unanimous consent between scholars on just how to make sense of Ockhamism. This paper illustratessomefundamentalfeaturesofOckhamismanddescribesitssemanticand metaphysicalimplicationswithinthedebateonfuturecontingents. AccordingtoalineofthoughtthatgoesbacktoArthurPrior(1967)–who,inturn, developed a suggestion received from Saul Kripke in a letter dated September 3, 1958(seePloug&Øhrstrøm,2011)–thebestwaytomakesenseofindeterminism consistsinrepresentingtemporalrealityashavingatree-likestructureinwhichthe “trunk”representsthepast,understoodasunchangeableorfixed,whilethemultiple “branches” are meant to account for the alternative ways in which the universe may evolve from a given moment (i.e., the present). The universe, following this metaphor, will be indeterministic if there exists more than one branch in the tree ofpossibilities. Notsurprisingly,thisway ofmodelingindeterminismhasbecome knownas“branchingtime”–wherethecoreconjectureisthatindeterminismentails branching. The tree model, among other things, has been extensively adopted in order to captureourpre-theoreticthoughtthatthefuture,unlikethepast,isopen.Theleading ideawasthatthefutureisgenuinely–i.e.,objectivetelyorontologically,asopposed to epistemically–openif therearebranchesonwhich,say,tomorrowa sea-battle willoccurandothersonwhichitwon’t–andnobranchcanbeprivilegedoverthe A.Santelli((cid:2)) UniversityofL’Aquila,L’Aquila,Italy e-mail:[email protected] ©SpringerNatureSwitzerlandAG2022 1 A.Santelli(ed.),OckhamismandPhilosophyofTime,SyntheseLibrary452, https://doi.org/10.1007/978-3-030-90359-6_1 2 A.Santelli others.Whatthisusuallymeansisthatifweweretopositsuchaprivilegedbranch, then time would be linear, and hence the future would be as closed as the past. Assomeadvocatesofbranchinginfactarefondofputtingit,“branchingrulesout actuality”,thatis, the possibility of pickingoutoneparticularfutureas theactual future, namely the one containing the course of events that will be realized. The futureinquestioniswhatBelnapandGreen(1994)hascalledtheThinRedLine. Even though the tree model has triggered valuable research both in logic and philosophy,over the past few years some scholars began questioning its apparent attractiveness.Inparticular,AndreaIaconaandFabriceCorreia–amongthemany whotookpartintheLanguageandTemporalityworkshopheldinL’Aquila(Italy), inSeptember2009–felttheneedtoreassesstheroleofthetreemodelinorderto dealwithsomeimportantissues,bothsemanticandmetaphysical,thatsuchamodel, ontheirview,hasleftunsettled.Thatneed,moresharedthanexpected,later grew intoavolumeentitledAroundtheTree(2013),alsoeditedbySpringer,inwhichthe authorsgatheredprominentcontributionsfromdifferentphilosophicalbackgrounds aimed mainly at provoking a substantive discussion about the tree model and its possible alternatives, as well as at providing additional insights on central topics oftenconnectedwithit. Inthisrespect,thepresentvolumeintendstofurtherdevelopIaconaandCorreia’s project. Indeed, its main purpose is to introduce and critically assess Ockhamism, namelythetheorythatinAroundtheTreehasrepeatedlyemergedasoneofthemain alternativestotheview,alreadymentioned,thatpositingaThinRedLineforcesus togiveupobjectiveindeterminism.Tothisend,italso bringstogetherestablished scholarsinthefieldsofmetaphysicsoftime,semanticsandtemporallogic,history ofmedievalphilosophy,andphilosophyofphysics,alllinkedbythecommongoal ofclarifyingthenatureoftheOckhamism,itshistoricalroots,andtheroleitplays inthecurrentdebateonfuturecontingents.1 The problemof future contingents,as is well known,is the problemof how to assignadefinitetruthvaluetosentencesregardingeventswhoseoccurrenceisnot inevitable. Traditionally, its first formulation dates back to Aristotle who, in the famous De Interpretatione IX, seems to claim that bivalence entails fatalism, the metaphysical doctrine according to which everything that happens, happens with necessity(where“necessity”herestandsfor“historicalnecessity”,thatis,necessity with respect to our past and present). Aristotle’s conviction is that, since fatalism hastheunacceptableconsequenceofdenyinghumanfreedom,itmustbeconcluded that the only way to secure the contingencyof the future consists in rejecting the 1Itisimportanttounderstandthatitisbeyondthescopeofboththepresentworkandthevolume toexploreindetailissuessuchasthenatureof(in)determinism,fatalismortheopennessofthe future,andhowthesenotionsareconnectedwithoneanother.Althoughtheyareallrelevantissues, IbelievethattheyarerelatedtocontemporaryOckhamismonlygenerically,andalsothataproper discussionoftheirconnectionwouldverylikelyrequireustowriteanothervolume.