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Rationality in Science , Religion , and Everyday Life

Rationality in Science , Religion , and Everyday Life. Part three of MA Course Knowledge, Rationality , and Society Emanuel R utten. Literature and Schedule. Literature

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Rationality in Science , Religion , and Everyday Life

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  1. Rationality in Science, Religion, andEveryday Life Part three of MA Course Knowledge, Rationality, and Society Emanuel Rutten

  2. Literatureand Schedule • Literature • MikaelStenmark, Rationality in Science, Religion, andEveryday Life(University of Notre Dame Press: Indiana 1995), Chs. 1-10 • Schedule • Tue Nov 25: Chs. 1-3 • Thu Nov 27: Chs. 4-5 • Tue Dec 2: Chs. 6-8 • Thu Dec 4: Chs. 9-10 • Links to Slides & Questions • Twitter: @emanuelrutten

  3. Chapter 1: Introduction

  4. Belief formation, revisionandrejection • Part of being human is to have the abilityto form, reviseandrejectvariousbelieves. Ourcognitivecapabilitiesincludebelief regulationprocesses • Whenit is thatpeople form, regulateandrejecttheirbelieves in a proper, responsible, or reasonable way? What are the conditionsforrational belief? • Are these conditions the sameforallareas of human life (science, religion, everyday life, etc.)? Are they the sameforall cultures? Andforalltimes? • In order toidentify these conditions we have toclarifywhatrational belief actuallyis, andwhetherit is the sameforallareas of life, cultures andtimes • The notion of rationality does notapplyonlytobeliefs. Human decisionsand actions canberational or irrational as well. Yet, our focus is on belief

  5. Science, religion, andeveryday life • Science is taken bymany as a paradigmexample of rationality. Any model of rationality must deal withtheoryacceptanceandrefutation in science • Religionoriginates in existentialexperiencesof joyandsuffering, meaningandalienation, guiltandliberation, etc. We mayaskwhat the conditions are forreasonablebeliefsabout the ultimate, the absolute, the sacred • Everyday life is notanoptional area and in it we have clearly the most of ourbeliefs. It is thereforealso a paradigm case formodels of rationality

  6. Theoretical, practical andaxiologicalrationality • What kinds of ‘things’ canberational or irrational? • Beliefs, decisions, actions, behaviors, evaluations, plans, strategies, people … • What kinds of ‘things’ are typically a-rational? • Trees, planets, cars, phones, tables, chairs, taste (e.g. pizza, ice-cream), art … • There are threeareaswhere we candecidewhatto do. But thenthere are threecontexts of rationality(Rescher) • Theoreticalrationality is aboutwhat we shouldbelieve or accept • Practicalrationality is aboutwhat we shoulddo or perform • Axiologicalrationality is aboutwhat we shouldvalue or prefer • Axiologicalrationality is requiredsincedecisions of peoplecanberationalonly in case the ends or aimstheytrytoachieve is in their real interest

  7. Axiom of reasonabledemand • Rationality has toberealistic in the sense thatitcannotrequire more thanwhat the supposed agent canpossiblybeexpectedto do (given the agentsactual ‘resources andcircumstances’ or ‘constitutionandpredicament’). • In short: ‘ought’ implies ‘can’ (Kant) • Yet, manymodels of rationality are aboutperfectagents. They introduce agents as purelytheoretical abstract constructions (idealepistemicbeings) • Therefore, manymodels of rationality are tooidealizedor utopiantoapply in aninterestingand relevant way toactuallimited human beingslikeus • Theyimplythatwe are usuallyirrational in most things we do, which is an absurd consequence. Modelsof rationality must take into account what we as real human beingscanreasonable do andwhat is not in our power to do

  8. Three waysto construct models of rationality • But are empiricalaspectstobe taken into account whenproposingmodels of rationality? Is itnotenoughto focus on strictlyconceptualandlogicalmatters? (This question can in factbeasked of anyphilosophical issue) • There are threephilosophicalmethods (forcreatingmodels of rationality) • The formal approach • The practiceorientedapproach • The contextualapproach • The first andthird are situated at each side of a spectrum. The second is aninter-mediatingpositionbetweenbothextremes

  9. The formal approach (purely a priori) • Formulationof a model of rationalitycanbedonewhollyindependentlyfromthe actualpracticesbyapplying strikt conceptualandlogicaltools • Pure conceptualandlogicalenquiry has complete authorityover the practicesthemselves. The actualpractices are strictlyspeaking irrelevant • The constructed model of rationality has tobeappropriateforanyreasonablebeingandno matter whatpracticethisbeing is involved in • In fact, the constructed model of rationality has toapplyforallpossibleworlds, that is to say, no matter what the world is like • No examination of (the history of) a practice is requiredtorecommendan adequate model of rationalityforthatpractice. One model appliestoall • Practicesthat do notsatisfy the pre-establisheduniversalandahistorical model (standards, criteria) forrationality are refuted as beingirrational

  10. The contextual approach (purelyempirical) • Formulation of a model of rationality is totallydependent on the actualpractices. Onlyan examination of these practices is needed. Nothingelse • The actualpracticesconstitutethemselves the onlyjustificationforwhat is andwhatisn’trationalwithinthem. External criteria are whollyrejected • Contextualistsmerelyexplicate the standards of rationalitythat are alreadygivenwithin the actualpractices. They are theirown ultimate authority • The standardsforrationality are thuswhollyinternalto the actualpractices. They are in otherwordspractice-determined • The standardsforrationalitycanand do in factsignificantlydifferbetweenthe variousactualpractices (such as betweenscienceandreligion) • Even the nature of rationality(the verymeaning of rationality)likelydiffersbetweenpractices. Rationalityjustisnot the sameforallactualpractices

  11. The practice-oriented approach (both) • There is a basis independent of eachpracticefromwhich we canassessitsrationalityandproposerationality criteria forit(contra contextualism) • It is possibletocriticallyestablishfrom a purelyphilosophical point of view, from the “outside” of a practice, standards of rationalityforthatpractice • Yet, it is requiredto have substantial contact witheach of the practices. We must take into account itsaims, activitiesandsituation(contra formalism) • The proposed model of rationalityfor a practicecanonlybe relevant for a practiceif we understandits means andends. Itsfunctionandnature • We must besensitivetowhatis going on in a practice, whatonetriestoachieveandwhat is achievable. Thisplacesconstraints on proposedmodels • The proposedstandardsforrationalitycanand do in factdifferbetweenvariousactualpractices. Yet, itsverynature or meaning is likelyuniversal

  12. Rationalityandreligion • A key issue is the applicability of rationalitytoreligion. In order toaddressthis topic properly we needtoextend the scope, namelyto the applicability of standards of rationalitytobothreligiousandsecularviews of life • The discussion of the rationality of religious belief is notonlyaboutwhetherreligious belief meets the criteria or standards of rationality, but alsoaboutwhatstandards of rationality are the approprateonestouse in this context • The goal here is nottoestablishwhethersome view of life is rational, but toidentify the proper standardsforassessing the rationality of views of life • Variousmodels of rationality are investigated in order toassesswhichof them is the most appropriatetouseforreligious belief. We thusexamine the conditionsfor a discussion on the rationality of religious belief • One option is the scientificchallengetoreligious belief. It has itthatallreligiousbeliefs must conform to the rationalitystandards of science • A relatedchallengeis evidentialism. It has itthatreligiousbeliefs are rationalonlyto the extendthatthere is sufficientevidenceforthem

  13. Models of rationality • A model of rationalityconsists of [i] an account of the nature of rationalitytogetherwith [ii] an account underwhatconditionssomething is rational (the standards or criteria of rationality) • The followingmodelscanbedistinguished • Formalevidentialism– There is onenature of rationalityandone set of standardsforrationality. This model is relatedto the formal approach • Socialevidentialism– There is onenature of rationality but different standardsfor different practices. This model is relatedto the practice-oriented approach • Presumptionism – There is onenature of rationality but differentstandardsfor different practices. This model is relatedto the practice-oriented approach • Contextualism – There are different natures of rationalityand different standardsfor different practices. This model is relatedto the contextualist approach • For socialevidentialismandpresumptionismonesometimessaysthatthere is one set of standards (becausestandardshere are stillstructurallysimilar)

  14. Chapter2: The Nature of Rationality

  15. The Nature of Rationality • Wat isrationality? What does itmeanto say thatsomething is rational? Is itpossibletoprovide a generalcharacterizationof rationality? • Without ananswertothis question itwillbedifficult or even impossibletoidentify proper standards (criteria, conditions)forwhen a belief or action within a certainpractice is rational • But is there a single meaning of rationality? Perhapsrationality has different meanings in different domains? In that case itisn’tunivocal • Descriptiveincommensurability thesis – Rationalityhas different meanings in different domains • Normativeincommensurability thesis – Rationalityshould have different meanings in different domains

  16. Four different aspects of rationality • We mentionedrationality’snatureandstandards. But there are fouraspects • The nature of rationality – What is rationality? What is itsmeaning? • Thestandardsof rationality– What are the conditionsforbeingrational? • Thereasonsof rationality– Whatmaycount as rationalevidence? • Theaimsof rationality– What are the ends or goals of rationality? • The differencebetweenstandardsandreasonscanalsobeunderstood as a differencebetweengenericanddetailedstandards. If a practice-orientedphilosopherholdsthatstandardsmay change betweenpractices, he or sheacutally means the detailedstandardsandnot the genericones • Examples of (generic) standards • One must always have sufficientevidenceforone’sbeliefs(evidentialism) • Onemayhold-on toone’sbeliefs as long as theyaren’trefuted(presumptionism)

  17. Four different aspects of rationality • Whatcounts as rationalreasons in onepractice (e.g., religion) maynotcount as rationalreasons in anotherpractice (e.g., science) because these practicesmay have different aims. (Thus the fourth aspect is actuallyaboutpractices) • Moreover, differences in rationalreasonsbetweenpractices do notalwaysentaildifferences in standardsbetweenpractices. Anddifferencesbetweenstandardsbetweenpractices do notalwaysentaildifferences in nature • When we askfor the nature, standards, reasonsandaims of rationality, we refersolelytonormativerationalityandnottogenericrationality • Genericrationality– refersto the capacityforreasoning. An agent has genericrationalityifit has the resources of reason. It thuscanberational or irrational. An entity without genericrationality is a-rational. It cannotberational or irrational • Normativerationality– An agent havinggenericrationality is normativelyrational (hereafter: rational) just in case itexcercisesitsreasonproperlyor responsibly. A belief or action is normativelyrationalifandonlyifit is or canbejustified

  18. Deontologicalrationality • Anycharacterization of the nature of rationalityneedsto take into account thatrationality is a normative concept (‘oughtto’) and a term of appraisal (‘positive attitude, approval’). One way of characterizingit is deontological • According to the deontological accountrationalityconsists in the fulfillmentof certainduties (responsibilities, obligations) in respect towhatone is doing (e.g., believing, acting). • In the context of belief (‘theoreticalrationality’) these responsibilities are calledepistemicresponsibilities. It leads toanethics of belief • The epistemicduties are prima facie andnotultima facie. Theycanbeoverriddenbyother non-epistemicduties in special circumstances • But what do these dutiesconsist in? Thisbringsus back to the level of (generic) standards of rationality. Examplesincludeevidentialism (never belief things without goodevidencefortheirtruth) or presumptionism (onemayhold-on tobeliefsprovidedthere is notsufficient counter-evidence)

  19. Means-End rationality • Anothercharacterization of the nature of rationality is means-end rationality. According toitrationalityconsists in the efficientpursuit of givenends. There is thusnothingthat is rationalper se. Rationality is alwaysgoal-relative • Rationality is abouthowtoachieveouraims as efficient as possible. It does nottelluswhat these aimsshouldbe. It is about means andnotaboutends • Toassesswhether a certaindecision is rational, we notonly have toknowpeople’s goals, but alsotheir resources andsituation (r- and s-relativity) • According to the objective account of rationalitywhat we do is rationalifitisprobablethatitwillsatisfyour goals in anefficientmanner • According to the subjective account of rationalitywhat we do is rationalifitseemsorappearstousprobablethatitwillsatisfyour goals efficiently • In that case rationalitybecomesalsorelativeto the information had by the agent

  20. A puzzleconcerningrationality John has been in a state of severe anxiety for years now. Recently he obtained strong evidence that he is going to die if he does not get rid of his anxiety. He also has strong evidence that the only way for him to acquire peace of mind is to believe that the universe will exist forever. Suppose that John has sufficient evidence for the claim that the universe will not exist forever. Still, in an ultimate attempt to save his life he starts to try to force himself psychologically to believe - contrary to the evidence - that the universe will exist forever. After two weeks he finds himself in a state of believing that the universe will exist forever. As a result he obtains the desired peace of mind and thus loses his anxiety. In this way he manages to save his life. Now, is John's belief that the universe will exist forever rational?

  21. Canbothcharacterizationsbecombined? • The characterization of theoreticalrationality as anepistemicduty does in factassume a goal: tobelievemanytruthsandeliminatemanyfalsehoods • But then the deontologicalcharacterizationfortheoreticalrationalitycanbereprashed as follows. People have the responsibilitytopursueefficient means forsatisfyingtheirepistemic goals • In additiontoepistemic goals there are also non-epistemic goals (such as well-beingand survival). Epistemicrationalityinvolvesonlyepistemicendsandnon-epistemicrationalityinvolvesonly non-epsitemicends • Are usefulness, simplicityandpredictabilityepistemic goals or not? • Notethatepistemicrationality is not the same as theoreticalrationalityandthat non-epistemicrationality is not the same as practical rationality (why?) • The deontologicaland means-end notions of rationalitycanbecombined: We have a dutytopursueourepistemicand non-epistemic goals efficiently • Scienceandreligion have complex (bothepistemicand non-epistemic) ends

  22. SomeExamples Mary believes in quantummechanicsbecauseshethinksthatthere is goodevidenceforitstruthsand her aim is to get in touchwithreality This is aninstance of theoreticalandepistemicrationality John believesthat the universewillexistforeverbecauseitgiveshimpeaceof mind and his aim is to get peace of mind This is aninstance of theoreticaland non-epistemicrationality Brigitte performs a daily walk becauseithelps her to get new research ideas, which is very important for her sinceshe wants tostudy the world This is aninstance of practical andepistemicrationality Dave engages in sports at his universitybecauseitkeepshimhealthy, whichsatisfies his goal of well-being This is aninstance of practical and non-epistemicrationality

  23. Epistemicand non-epistemicreasons • What these examples show is that we can have epistemicand non-epistemicreasonsforwhat we believe or forour acts because we can have epistemicand non-epistemicendsforbelievingandacting • A goodepistemicreasonfor a belief or act connects the belief in anappropriate way to the epistemic goals that are presupposed (e.g. believingonlytruths) • A goodnon-epistemicreasonfor a belief or act connects the belief in anappropriate way to the presupposed non-epistemic goals (e.g. peace) • If the goal is complex (i.e., consists of bothepistemicand non-epistemicends), agents are to take intoaccount epistemicand non-epistemicreasons

  24. Towards a holisticrationality • The combinednotion of rationality (“a dutytoestablishefficientandsufficient means forourends”) is stilltoonarrow. For the assessment of appropriateends is still out of scope. It is stillonlyabout means • Ouronlyduty is tofindefficient means forwhatever we want. Reason does nottelluswhereto go, itonlytellsushowto get there. It is the slaveof the passions(Hume) • Such a limitedconception of rationalitygoesstronglyagainstourintuitions. How couldsomeonewhoefficientlychooses his or her total ruin berational? We thusneedtobeabletorationallyassessandchooseour goals as well • Plausibly, meaningless, worthless or destructiveends are notrational. Endsthat are not in people’s real or best interests are notrationaleither. And the sameholdsforendsthat are contrarytoour real needs • Reasoningaboutends is thuscloselyrelatedtoreasoningaboutvaluesandpreferences. We thereforeneedtobring in axiologicalrationality

  25. Towards a holisticrationality • On a more inclusiveconception of rationality a rational person has a dutytochooseappropriate or valuableends (endsthat are in his or her best interest) andtofindsufficientandefficient means toachievethem • But phrased in this way, the conception is stilltoonarrow. For efficient means that are destructive, contrarytoour real needs or contrarytoour best interests are notrationaleither. Ourmeans must alsobeappropriate • The axiologicaldimension is thus relevant forourendsandour means • On the holisticconception of rationalitywe have a dutytochoosevaluable or appropriateends (endsthatsatisfyour real needs) andtofindsufficient, efficientandappropriate means forachieving these ends • The holisticconception of rationality has both a theoretical-practical side or dimension(conditional: establishing proper means-end connections)andanaxiologicaldimension(categorical: establishingappropriate or valuableends)

  26. Chapter 3: ScienceandFormalEvidentialism

  27. The formal approach toscientificrationality • The best placeto start forintroducingformalevidentialism is withsciencesince most ifnotall adherents of formalevidentialism take sciencetobe the paradigm of rationality. Solet’s look at howformalists view science • The formalist holdsthatphilosophy of science is the study of the logicalproperties of and the logical relations betweenscientificpropositions or collections of propositions (theories). It is primarilylogical analysis • The idea is thatthere is a ‘logic’ underlying the methods of scienceand the task of the philosopher of science is toexplicatethis logic a priori • Logicality thesis: The rationality of scienceamountsto a logical system • There is no needtostudyactualscientifictheories. Simple generalizationslike ‘Allswans are white’ properlyrepresent the logicalstructure of theories • According tothis view philosophy of science is the study on how a rationallyidealscientistshouldproceedandwhat he or sheshouldrationally accept

  28. Scientificevidentialism • The first requirement is thatsciencedemandssufficientevidence(e.g., correspondencetoempirical data) foralltheoriesitaccepts • Acceptedtheoriesshouldbeacceptedwith a firmnessproportionalto the probabilityassignedtoit on the basis of the availableevidence “It is notwhat the man of sciencebelievesthatdistinguisheshim, but howandwhy he believes it. His beliefs are tentative, notdogmatic; they are based on evidence, not on authority or intuition” (Russell) • The first part is thusanacceptance of evidentialism: It is rationalto accept a theoryonlyif, andto the extendthat, there is are goodreasonstobelievethatit is true. It consists of twoprinciples • The evidentialprinciple: It is rationalto accept a propositiononlyifthere are goodreasons (or evidence) tobelievethatit is true • The proportionalityprinciple: The firmnesswithwhich a proposition is acceptedmust be in proportionto the strength of the evidenceforit

  29. Scientificevidentialism • But wereto start? Typically, it is claimedto start fromsingularobservationalclaimssuch as “At time t andplace p event e occured” or “There is a tree in front of me”. But howtojumpfrom these to the universalclaimsof theories? • Besides, accordingto the evidentialprinciplescientists must alsoprovideevidencefortheirobservationalbeliefs. In fact, they must provideevidenceforthatevidence as well, andso on. Soaninfiniteregressseemsunavoidable • Topreventsuchregress the generalcharacter of the evidentialprinciple must begiven up. We needtodistinguishbetweennon-basic or derivedbeliefs (in need of evidential support of otherbeliefs) andbasic beliefs(that do notneedevidential support of otherbeliefs). This is calledfoundationalism • Observationalbeliefs are then taken as basic (‘foundational’). In fact, it is not even possibletoprovide non-circulair evidenceforit (why?) • Revisedevidentialprinciple: It is rationalto accept a non-basic propositiononlyifthere are goodreasons (or evidence) tobelievethatit is true

  30. Foundationalism • The relationbetweenourbeliefs is asymmetrical. The inferentialjustificationgoesonlyfrom basic beliefsto non-basic beliefs. Further, belief Aconstitutesevidence (or a reason) for belief Bonlyifit is more basic thanB • Foundationalismdiffersfromcoherentism (that does notdistinguish basicfrom non-basic beliefs) • Although basic beliefs do notneedevidence, they are notgroundless. Theycanbejustified. But thisjustification is non-inferential or immediate (e.g., rests on sense experience) • What types of beliefscount as properly basic? • Strong foundationalismholdsthat basic beliefsshouldbe immune todoubt. They are thuseitherself-evident (1+1=2) or incorrigible (I amvisuallyaware of ‘green’) • Weakfoundationalismholdsthat basic beliefs must behighlylikelytrue. They are self-evident, incorrigible or evident to the senses (There is a tree in front of me) • Somephilosophers (e.g., Plantinga) go furtherandalsoallowforexample memory beliefsas basic. In thisandprevious case basic beliefs are defeasible

  31. Foundationalism • Fallibilism is the view thatallourbeliefsmightbe wrong. Foundationalism is nottobecontrastedwithfallibilism (sinceweakfoundationalists are in factfallibilists) but withcoherentism (no distinction basic and non-basic) • According tofoundationalism a belief is rationalonlyifthat belief is either (a) a properly basic belief, or (b)canbeinferentiallysupportedbyproperly basic beliefs or otheralreadyderived non-basic beliefs; and (c) the strenght of the non-basic beliefs are proportionalto the support from the foundation • Evidencereferstoinferentialjustification of a non-basic belief. Evidenceforsuch a belief referstoinferentialjustifiersforit, i.e. the belief is inferentiallysupportedbyotherbeliefs. Sense experienceand memory are examples of non-inferentialjustifiersfor basic beliefs (these justifiers are calledgrounds) • The experience of snowing non-inferentiallyjustifies the belief thatit is snowing • The belief that John is abroadcanbeinferentiallyjustifiedfromotherbeliefs

  32. The rules of science • How can we justify the step fromsingularobservational statements to the general claims of scientifictheories? According to the formaliststhere are scientificrules(‘the logic of science’) forrationaltheorychoice • Scientificrationality is rule-governedor -determined. It’s aboutrule-following • SimilartoFrege’sdeductive logic formalistsaimedtoestablishaninductive logicforrationallyassessing, comparing, acceptingandrefutingtheoriesgiven the availableobservational data • Formalistsknewthatdueto the inductionproblemscientifictheoriescannotconclusivelybeverifiedby the availableempiricalevidence. So, inductivelogic willnotbeabletoinfertheorieswith absolute certaintyfromobservations • Therefore, acceptableinductiveargumentsneedto show onlythat the conclusion (e.g., the theoryunderconsideration) is probablegiven the evidence. And the inductive logic must enable the scientisttocalculate a priori precisely the probabilityof the theorybeingtruegiven the data

  33. Bayesianism • According to the formalistsinductive logic has full authority, notscientificpractice. Today’s dominant model of inductive logic is developedbyBayes • Scientists are idealagents (Bayesianagents) thatcompute the probabilities of their hypotheses beingtrue (given the evidence)byusingBayes’ theorem(whichcanbederivedfrom the axioms of mathematicalprobabilitytheory) P(e|h & k) P(h|e & k) = x P(h|k) P(e|k) P( ... | … ) stands for ‘The probabilitythat … given …’ h is the hypothesis (theory) underconsideration e is the availableempiricalevidence k is the background knowledge P(h|k) is called the prior probability (‘the prior’) P(e|h &k) is called the likelihood The ratio is called the explanatory power Objective (Subjective) Bayesianism takes the priors tobeobjective (subjective)

  34. Popper’s logic of conjecturesandrefutations • Popper famouslyrejectedanyattempttodevelopaninductive logic. We shouldnottrytosupporttheories (general claims) withobservations. But he agreesthatscience has a logic and is aboutfollowingrules • Popper is thus a formalist because he accepts the logicality thesis • He proposes the following logic. Evidenceshouldonlybeusedtorefute or falsifytheories. Thisrequiresonlydeductive logic since e.g. ‘Allswans are white’ is deductivelyrefuted or falsifiedbyoneobserved black swan • Scientistsneedtoconjecturerefutable or falsifiabletheoriesandactivelyseekevidencethatrefuteor falsifythem. Once a theory has survivedseveralfalsificationattempts(tests) it is corroboratedandcanberationallyaccepted • Likeallformalists, his account of scientificmethod is intendedtobeuniversalandahistorical. He thusacceptsthe stability thesis of formalism, namelythat the rationalityof the scientificmethod is invariant over time and domain

  35. The ruleprinciple • Formalistsaccept the ruleprincipleaccordingtowhichallrationalbeliefs (and actions) must bearrived at by means of appropriaterules • Rules help toestablishlogical or necessaryconnectionsbetweenpropositions • Rules help toinferandrefutetheoriesfromavailableevidence (observations) • Rules help toreduce or even eliminatearbitrariness (‘predictableoutcomes’) • Rules limit room fordivergingconclusions (‘universal or objectiveoutcomes’) • Rules canbeapplied in anypossible context (‘practiceindependence’) • Rules ensurethatconclusionsfolllownecessarilyfrom the availableevidence • Rules ensureanoutcome in a finitenumber of steps (‘algorithm’) • Rules applicationrequires no detailedknowledge of the content (‘formal’)

  36. The formalists’ conception of rationality’snature • Both a deontologicaland a means-end conception of rationalitycanbe found amongformalphilosophers of science • With respect to the deontological side scientists have intellectualduties (e.g., only accept theoriessupportedbygoodevidence, trytofalsifytheories, etc.) • With respect to the means-end side the rationality of sciencedepends on whetherscientificmethods are efficientin achieving the aims of science • Different accounts of the goals of science: truth, predictability, usability, etc. • It must bepossibletocomparetheoriesrelativeto the agreed goal(s). Ifthere is sufficientevidencethat T2 is goal-superior to T1 - and the scientific community perceivesthis - thanthey must abandon T1 in favour of T2 • If the deontologicalrationalitycanbethought of as a dutytosatisfycertainepistemicand non-epistemicends, bothconceptionscanbecombined: scientists have a dutytoestablish proper connectionsbetweentheirscientifictheoriesandtheirscientificends

  37. Demarcatingscienceand non-science • Someformalists have claimedthatscientificrationality is the only form of rationalitythatexists: “Tofailtobescientifc is tofailtoberational” • Otherformalists go less far but are stillquiteskepticaltowardsbeliefsthat do not meet the(ir) standards of scientificrationality • But howshouldsciencebedemarcatedfrom non-science? • Positivistsholdthat the demarcationcriterion is the same as the onethattheybelieveseparatesmeaningfulfrommeaningless claims: the verificationprinciple: anempirical statement has meaningiffit is empiricallyverifiable • Next tomeaningfulempirical claims, positivists accept analytic claims. These are conceptualtruths. They are truebyvirtue of theirownmeaning (e.g., 1+1=2) • The verificationprinciple is self-refutingthough (why?) • Popper’sdemarcationcriterion is notmeanttodraw a line between claims that are meaningfulandmeaningless. He holdsthat non-scientific claims canstillbemeaningful. For Popper scientific claims are falsifiable

  38. ExpandingtoFormalEvidentialism • FormalEvidentialismis the model of rationalitythatresultsif we expand the formal approach toscientificrationalitytoallareas of human life • Evidentialprinciple (‘beliefsneedgoodinferential or non-inferentialevidence’) • Proportionalityprinciple (‘believewith a firmnessproportionalto the evidence’) • Logicalityprinciple (‘rationality matter of practice-independent a priori analysis’) • Ruleprinciple (‘belief formation is a matter of followingalgorithmicrules’) • Foundationalism (‘distinctionbetween basic and non-basic beliefs’) • Formalevidentialists do notpay attention to the actualagentsand the actualpractices. There is no analysis of howpeople in different practicesactually form andregulatetheirbeliefs. Actual events are mereillustrations

  39. The locus of rationality • Formalevidentialistsembrace the logicality thesis (rationalityboilsdown toa logical system). So, the locus of rationality is ultimately in systems of propositions. Only (relations between) propositionscanbe (ir)rational • Relations betweeninferentialevidenceandtheoriesand relations between basic and non-basic propositions • A rational belief is thusnothing more than a belief in a propositionthat is rational(lyjustified). And a rational person is nothing more than a person whobelievesonlyrational(lyjustified) propositions • It followsthatforformalevidentialismrationality is not a relationbetween a particular kind of agent, in a particular kind of situation, and her beliefs. That’swhy concrete practices do not matter forformalevidentialists • Formalevidentialistsembraceperson-independent idealizeduniversalmodels • Rationality is ultimatelyconnectedtopropositions, not persons

  40. Externalandinternalrationality • A distinctioncanbe made betweenexternalandinternalstandards (criteria, conditions)forrationality • Internalstandardsdeal withhowagentsoughttogoverntheiracceptedbeliefs. The focus is only on the beliefs present in anagent’s belief system • Principle of logicalconsistency • Externalstandardsdeal with the relationbetweenanagent’s belief system and the outsideworld. It is aboutwhatstandards a belief must satisfybeforeit is allowedto enter or stay in anagent’s belief system • Evidentialprinciple, Principle of proportionality or Principle of proper basicality

  41. Internalstandardsforrationality The consistencyprinciple Sinceanyabsurditycanbederivedfrom a logicalcontradiction (‘P andnot-P’) itis oftensuggested as aninternal standard that the collection of beliefs of the agent (‘the agent’s belief system’) must belogically consistent An agent shouldnotbelieveboth ‘Allswans are white’ and ‘There is a black swan’ The principle of deductiveclosure It is oftensuggested as aninternal standard that the logicalconsequences of what is believedshouldbeacceptedby the agent as well Ifan agent believes ‘Allswans are white’ and the agent alsobelieves ‘John owns a swan’, then the agent shouldalso accept ‘The swanthat John owns is white’

  42. Revisedversion of bothinternalstandards • Manyformalistsacknowlegdethatbothstandards are notfeasiblebecauseit is impossibleforpeople (havinglimitedmentalpowers) to meet them • People have manybeliefsandaren’tabletoverifywhethertheirwholebelief system is consistent. Neithercantheyinferallconsequences of theirbeliefs • Moreover, itcanbe in factarguedforthatour belief systems cannotbebothreasonableand consistent (how?) • Yet, bothstandardscanberephrased as ideals. For rationalityit is notrequiredtoactually meetbothideals. It is sufficientto do the best we cantosatisfy these ideals • Revisedprinciple of consistency– People are rationalonlyiftheyalwaystrytheir best tobringitaboutthattheyeliminate as manyinconsistencies as possible in whattheybelieve • Revisedprinciple of deductiveclosure– People are rationalonlyiftheyalwaystrytheir best tobringitaboutthatthey accept as manyconsequences of whattheybelieve

  43. A problemfor ‘deductiveclosure’ Consider Brigitte. Shebeliefsonlypropositionswith a probability of beingtrue of 80% or higher. Supposethatshebelieves‘Allswans are white’ withprobability 80% and ‘John owns a swan’ withprobability 80%. According to the principle of deductiveclosuresheshould acceptas well ‘The swanthat John owns is white’. But thiscannotbe right, since the likelihood of thisproposition is (0.8)2 andthereforelessthan 80% The problembecomes even more pressing if we consider cases withmany different propositions. Holding on todeductiveclosurewouldentailthat we have to accept propositonsthat are in facthighlyunlikely, which does notseemtobe a rationalthingto do To follow-up on this. Supposethat Brigitte has beliefs A, B, C and D withlikelihoods 80%. Supposethat A, B and C togetherentailnot-D. Is Brigitte’s belief system contradictory? Is Brigitte forcedto belief a contradictionif we take into account the principle of deductiveclosure? Andif we take into account Brigitte’s ‘80% rule’ as well?

  44. Chapter 4: The Scientificand the Evidentialist Challenge toReligious Belief

  45. The 20thcenturychallengetoreligious belief • In the 20thcentury, much of the discussionaboutwhether or notreligious belief is rationalor justifiabletookformalevidentialismforgranted • It was notuntil the end of the 20thcenturythatphilosophers of religionstartedtorealizethat the issue of the rationality of religion is as much a question about the notion of rationalityitself as itsapplicationtoreligion • An early 20thcentury view of the rationality of religious belief was providedbypositivism. Positivismcanbecharacterized in the following way • A statement is meaningful or has cognitive content ifandonlyifit is analytic or empiricallyverifyable(the verificationprinciple of meaning) • A meaningful statement is trueifandonlyifit is logically proven (foranalytical statements) or empiricallyverified (forempirical statements) • The abovetwoprinciplesconstitute the scientific standard of rationality. Thusallmeaningful(andthusallrational) beliefs must bescientificbeliefs. Rationalityisscientificrationality. Tofailtobescientific is the same as tofailbeingrational • All non-scientific statements (religion, art, etc.) are nonsense, like“QgaWDzz”. Sothere are not even false. They are justmeaningless – empty of congitive content

  46. The verificationistchallengetoreligious belief 1. A statement has cognitivemeaningifandonlyifit is analytic or empiricallyverifiable (the verificationprincipleof meaning) 2. Religious statements are neitheranalytic nor empiricallyverifiable • Therefore, religious statements are cognitivelymeaningless • Soreligious statements, such as “God exists”, are not even false. They say nothingfalse, becausethey say nothing at all. They are pseudo-statements • We must distinguishbetween the semantical question of religious belief (are these beliefsmeaningful?) and the epistemological question of religious belief (are these beliefsrationallyacceptable?) • Sinceaccordingto the verificationprinciple of meaningreligiousbeliefs do not pass the semantic test, the second never arises. Religion is on this view thusstrictlyspeakingnot even irrational. It is a-rational

  47. The falsificationistchallengetoreligious belief • Philosophers of religionlikeFlewreplaced the positivisticverificationprinciple of meaningwith a falsificationprinciple of meaning • A statement is cognitivelymeaningfulifandonlyifit is analyticor empiricallyfalsifiable(i.e, it is possibleto say upfront in whichsituationsit is falsified) • Thisprinciple leads to the falsificationistchallengetoreligious belief 1. A statement has cognitivemeaningifandonlyifit is analytic or empiricallyfalsifiable (the falsificationprincipleof meaning) 2. Religious statements are neitheranalytic nor empiricallyfalsifiable • Therefore, religious statements are cognitivelymeaningless

  48. Respondingtobothchallenges • Manyphilosophers of religionwhowantedtohold on torationallyjustifiedreligiousbeliefs, felt the needtosomehow meet these challenges • Typicallytheyaccepted the first premise of bothchallenges, andtriedtoarguethatreligious discourse is compatible with the verification or falsificationprinciple. That is, theyrejected the second premise • But thensomestartedtorealizethatbothprincipleswerethemselvesproblematic. They are accordingtotheyownstandardsmeaningless. Therefore, they are self-referentially incoherent (Plantinga) • Moreover, itbecameclearthatnot even science is abletosatisfy these demands. For manyscientifictheoriesit is notpossibletospecify the verification or falsificationconditions • The consensus becamethatbothprinciples are inadequate. A statement does not have toadhereto these principles in order tobemeaningful • Religiousbeliefs passes the semantic test. But cantheyberationallyjustified?

  49. The scientificchallengetoreligious belief • Ifreligiousbeliefs are cognitivelymeaningful, the crucial question becomeswhetherthey pass the epistemological test. Are these beliefsrational? Cantheyberationallyaccepted? • We maythenconsider the followingscientificchallengeto the rationality of religious belief 1. Religiousbeliefs must fulfill the same, or at leastsimilar, standards of rationality as scientificbeliefs in order tobeconsideredrational 2. Religiousbeliefsdo notfulfillthe same, or at leastsimilar, standards of rationality as scientificbeliefsdo • Therefore, religiousbeliefs are irrational • Surely, togivethischallenge content one must specifiy the standardsof rationalityscienceonethinkssciencesatisfies

  50. Respondingto the scientificchallenge • Religiousbelieverscanrespondtothischallenge in three different ways • The strong response – Accept the first premiseandreject the second byarguingthatreligion does in factfulfill the same or similarrationalitystandards as science • The differentiation response – Reject the first premisebyarguingthatreligiousbeliefs are rational but meet (wholly) different standards of rationality as science • The irrationality response – Accept the scientificchallenge but claim thatthis does notcountagainstreligion, sincereligion has never meanttoberational

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