Stephan Schmid Three Varieties of Early Modern Scepticism Introduction: RichardPopkin on Early Modern Scepticism Scepticism loomed large in the earlymodern period. In fact,manyphilosophers from the late sixteenth until the midstofthe eighteenth centurygrappled with the prob- lem of how to justify our knowledge claims in amuch more explicit and fundamental waythan theirAristotelian forerunners had.¹ In numerous articles and books, partic- ularlyinthe latest edition of his volume TheHistoryofScepticism from Savonarola to Bayle,Richard Popkin argued that the earlymodern obsession with scepticism was prompted by the rediscovery of SextusEmpiricus’swritingsfrom the second century CE. As Popkin puts it,the reception of Sextus’swritingsled to “an insoluble crise pyr- rhonienne,asthe various gambits of Sextus Empiricus are explored and worked out.”² While Sextus’ssceptical considerations were first applied in theological con- texts and religious debates,Popkin explains, they weresoon transferred to other areas as well. In Popkin’sdiagnosis,this led to a nouveau pyrrhonisme,which “was to envelop all the human sciencesand philosophyinacompletesceptical cri- sis, out of which modernphilosophyand the scientificoutlook finally emerged.”³ It is hard to overstate the importance of Richard Popkin’swork on the history of scepticism. Not onlydid his investigation of earlymodern scepticism bring to the fore authorswho werewidelyneglectedbefore him, but it also pavedthe wayfor arange of outstanding studies in the history of earlymodern scepticism, which would have been plainlyimpossible withouthis pioneering work. All these merits notwithstanding and without denying due credit to Popkin’sex- ceptional historiographical work, Iwant to challengehis main tenet thatthe early Iamgrateful to discussions with ZevHarvey, Yitzhak Melamed, José María Sánchez de León Serrano, and Máté Veres and the excellent stylistic suggestions by Anthony Paletta and Yoav Meyrav,which improved thischapter.Ialso thank the Maimonides Centre forAdvanced Studies, DFG-FOR 2311, formakingthischapterpossible in the first place. This is not to saythat Aristotelian philosophers wereuninterested in sceptical or even epistemo- logical questions.This long-standing historiographical prejudice is finallyabout to be corrected. Fornuanced investigations into medieval or Aristotelian debates about scepticism, see Dominik Per- ler, Zweifel und Gewissheit: skeptische Debatten im Mittelalter (Frankfurt am Main: Klostermann, 2006), and Henrik Lagerlund, ed., Rethinking the HistoryofSkepticism: The Missing Medieval Back- ground (Leiden: Brill, 2014). RichardPopkin, TheHistory of Scepticism fromSavonarolatoBayle (Oxfordand New York: Oxford University Press, 2003), 5. Popkin, HistoryofScepticism,59. OpenAccess. ©2019 Stephan Schmid, published by De Gruyter. This work is licensed under the Creative CommonsAttribution-NonCommercial-NoDerivatives 4.0 License. https://doi.org/10.1515/9783110591040-011 182 Stephan Schmid modernperiod wasshaken by aPyrrhonian crisiswhich then led to a nouveau pyr- rhonisme. Iamnot the first to do so, but my criticism is different from previous ones. In order to clearlyarticulate my objection and to distinguish it from other critiques, it is important to distinguish twodimensions of Popkin’smain tenet. Popkin’sclaim that the earlymodern period was characterised by a crise pyrrho- nienne can be read in two ways—and it seems that Popkin is happy to defend it in both. In one reading, which highlights the historicaldimension of Popkin’stenet, he makes aclaim about the historical origin of earlymodern scepticism, stating that it was triggered, influenced, and inspired by the rediscovery and reception of SextusEmpiricus’swritings. In another reading,which emphasises the taxonomical dimension of Popkin’stenet,hemakes aclaim about the nature of earlymodern scepticism, stating thatitisindeed aform or species of Pyrrhonian scepticism and is thereforeaptly described as “new Pyrrhonism” (nouveau pyrrhonisme). While most critics of Popkin focused on the historical dimension of Popkin’stenet and ar- gued that earlymodern scepticism was influenced and inspired by many other writ- ingsand traditions besides thoseofSextus Empiricus,⁴ here Iwant to takeissue with the taxonomical dimension of Popkin’sclaim. More precisely, Iwillargue that under- standing earlymodern scepticism as aspecies of Pyrrhonism is misleading at best. Even the two most famous earlymodern sceptics,René Descartes and David Hume,I submit,developed and employed varieties of scepticism which are distinctivelynon- Pyrrhonian.⁵ In addition, Iargue that distinguishing between different varieties of scepticism is of pivotal historicalimportance insofar as appreciating the fact that Pyrrhonian, Cartesian, and Humean scepticism differ in crucial ways from one anoth- er is keytounderstanding the historicaldevelopment of sceptical ideas. These three varieties of scepticism differ from one another in that each is in an important sense strongerorbroader than its antecedent versions; in otherwords, each calls into ques- tion what had been taken for granted by their antecedents. In particular,itisimpor- tant to distinguish between Cartesian and Humean scepticism in order to understand Kant’sphilosophical project after the earlymodern period. Kant’sproject was devel- oped in response to Hume’sscepticism about causation,which is different from both Good examples areJosé Raimundo Maia Neto, “Academic Skepticism in EarlyModern Philosophy,” Journal of the HistoryofIdeas 58, no. 2(1997): 199‒220; Dominik Perler, “WasThere a ‘Pyrrhonian Crisis’ in Earlymodern Philosophy? ACritical NoticeofRichardH.Popkin,” Archiv fürGeschichte der Philosophie 86,no. 2(June 2004), 209‒20;and Ian Maclean “The ‘Sceptical Crisis’ Reconsidered: Galen, Rational Medicine and the Libertas Philosophandi,” Early Science and Medicine 11, no. 3 (2006): 247‒74. By this restriction Idonot mean to implythat the twovarieties of scepticism developed by Des- cartesand Hume arethe onlyvarieties of scepticism to be found in the earlymodernperiod nor that they wereexclusively and originallydeveloped by Descartes and Hume. My restriction is simply duetothe fact that Descartes and Hume areboth famous and highlyinfluential earlymodernphilos- ophers. Three Varieties of Early Modern Scepticism 183 Cartesian and Pyrrhonian scepticism.⁶ Thus, understandingthe history of scepticism in general—and the proper targetofKant’sphilosophising in particular—requires us to appreciate varieties of scepticism different from the Pyrrhonian scepticism pre- sented by SextusEmpiricus. The paper consists of four sections. In section 1Iprovide abrief characterisation of Pyrrhonian scepticism on the basis of Sextus Empiricus’sdescription of Pyrrhon- ism in his Outlines of Scepticism.This will set the basis for my comparativeanalysis in the two subsequent sections, devoted to the two presumably most famous mani- festationsofscepticism in the earlymodern period: section 2will be concernedwith the “hyperbolic” scepticism of René Descartes,which he famouslydevelops in his Meditations,while section 3will focus on DavidHume’sscepticism about causation. Section 4willsummarise my findings. 1Pyrrhonian Scepticism We can onlyproperlyassess the taxonomical correctness of Popkin’stenet,according to which the earlymodern period was shaken by aPyrrhonian crisis which led to a new Pyrrhonism, once we clarify the meaning of Pyrrhonian scepticism. Onlythen can we compareitwith earlymodernvarieties of scepticism. At this point,one might raise afundamental objection to my project.Describing Pyrrhonism as avariety of scepticism parallel to earlymodernvarieties presupposes that ancient Pyrrhonism is an intellectual endeavour of the very same form or type as modernscepticism, such that both enterprises are forms of “scepticism” in the same sense. As recent scholarship in ancient philosophyhas shown, however,this as- sumption is highlyproblematic.⁷ For, unlike modern scepticism, which is concerned with underminingknowledge claims about certain domains by raising doubts about these domains, ancient Pyrrhonism is not particularlyconcernedwith doubtatall. In fact,there is not even an ancient Greek term for “doubt,” and if the Latin term du- bitatio is usedintreatises in the ancient sceptical tradition, it is not wielded in any This is meticulouslydefended by Michael Forster, Kant and Skepticism (Princeton: PrincetonUni- versity Press, 2008). See for instanceMichael Williams, “Descartes’ Transformation of the Skeptical Tradition,” in The CambridgeCompanion to Ancient Scepticism,ed. RichardBett (Cambridge and New York: Cambridge University Press, 2010), 289‒91,who lists altogether nine differences between Pyrrhonian and Des- cartes’sscepticism. Other enquiries intothe differencebetween ancient and (early) modern scepti- cism areMyles Burnyeat, “Idealism and Greek Philosophy: What Descartes Sawand Berkeley Missed,” ThePhilosophical Review 91, no. 1(January 1982):3‒40;and José Luis Bermúdez, “The Orig- inality of Cartesian Skepticism: Did It Have Ancient or Mediaeval Antecedents?” HistoryofPhilosophy Quarterly 17,no. 4(October 2000): 333‒60. 184 Stephan Schmid technical sense.⁸ The Greek word skeptikos simplymeans “seeker” or “investigator.” This is exactlyhow ancient sceptics conceivedofthemselves: as investigators inter- ested in the very questions of physics, ethics, and logic addressed by theirdogmatic opponents. Unliketheir opponents, however,they recommended suspending judg- ment about these matters since they