[quine w v] naturalism; or, living within ones mea(bookos.org)

8/12/2019 [Quine W v] Naturalism; Or, Living Within Ones Mea(Bookos.org)

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. INaturalism; Or, Living Within One s Meansw v QVINB

torHenri Lauener s sixtieth birthdayAbstract

Naturalismholds that there is no JUsher accessto truth thaD empiricaDy testable hypo-theses. Still it does not repudiate untestablohypotheses. bey fill out iDtendcesof1beo1y andlead tQ furt:helo ~ t h s s thatuetestable.A hypothcisis J8 tested bydccfuc:ing from it anda baCkgroundofaccepted theory, someob-servationcategorical thatdOesnot folfOwfrom the backgrounda1oDo lbis categorical,ageneraIiZed conditiODalcompoundedof two observation 1SCDteDces,admits in tumo apriDdtive ex-perimental test. . .1 0 o ~ d sentoDces themselves,liko apecriesandbird calls, u e in hoJopbrasticUlO-

ciadoD With ranau of noural Jntab DoqOtadOD ofdetermfnate objects figures neither fa thIaa.uocfation Doria deducingthe eategerical from the scientifichypotheses. HeDce tho fndetermiJIacy o Ieferaace; is puzeJ.y auxiIiaIy to tho st:l1ICtlml Ofthooxy Iiutb. however, isseen stiIlutranscendollt at leastiD this e S O ~ w e s a y ofa suporsodcd scientifictheorynot that itceased to be true, butthat it is found to have been false. . .Names ofphilosophical positionS are a necessary eviL They are necessarybecause we need tQ refer to a stated position or doctrine from time to time,and itwould be tireSOme tokeep restating it.Theyare evil in tbat theycome tobe conceived as deSignating schoolsofthoupt, objectsof loyalty from withinand o j ~ of obloquy from without, andhence obstacles, within andwithout, to the pursuit truth.In identifying the philosophicalpositionthat I callnaturalism, then, I shalljust bedescribing my oWli p(>sition, without prejudice to possibly divergentuses ofthe term ID heories nd hlngs Iwrote that ~ t u r a l i s m is the recog ; nition that it is science itself, andnot in some priorphilosophy, that re-ality is to be identified and described ; again that it is abandonment of thegoalofa first philosophyprior tonatural science (pp. 21, 67). T h ~ ~ e -teriz8tions convey th right moQd, but they would fare Poorly in adebate.How much qualifies as science itself and not some prior philosophy ? Harvard University, USA

iaIeciica. VoL 49,N 2 4 (1995)


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252 W.V.Qaine Naturalism; Or, LivingWithin One's Means 253 .It1 science itself I certainlywant to indude the farthest flights of physicsaDd cosmolo81l as well as experimental psychology, history, and the ~ o e i a l.sciences.Also ~ t i c : s , insofarat leastas it is applied, for it is indispens-. able to natural sclence.What thea am Iexcluding as somepriorphilosOphy,andwhy? Descartes dualism between miDd andbody is called m e t a p ~ y s i c s ,but it could as weD be reckoned as science, howeverfalse. He even had.a cau

sal theory of the Interacdoft ofmind and body through the pineal gland. If Isaw indirect explanatory benefit in positing sensibilia, possibilia,spirits, aCreator, I would joyfully accord theJn scientific status too, ona parwith suchavowedly scientific posits as quarksandblackholes. What then h v I bannedtinder thenameof prior philosophy? .Demarcationisnotmy purpose.My pointin thecharacterizations ofnatu-ralism that I quoted isjust thatthe mostwecan reaso:i1ablyseek insupportof.an inventory and description of reality is testability of its observable couse-. quences in the time-honored hypothetico-deductive way - wher.eof m?reanon. Naturalism need not cast asperSions on irrespoDSlole metaph)'Slcs,.however deserved,much less on soft sciences or 011the speculative reaches ofthehard ones, exceptmol r as a firmer basis is claimed forthemthan theexperimentalmethod itself. naturalistic renunciation shows itselfmost clearly and significantlyis in naturalistic epistemology. VarioUs epistemologists, from Descartes toCarnap, had sought a foundation for ~ t u : r a l s c i e n ~ in mental enti,ties, theflux of raw sense data. Itwas as i fwe JDlght first fashion a s ~ l f s u f f i C 1 e n t andinfallible loreofsensedata innocent ofreferenCe to physical things, and thenbuild out theory of theexternalworld somehow on that finished foundation.Thenaturalisticepistemologistdismisses this dreamofprior sense-datumlanguage, arguing that thepositingof physical things is itself our indispensabletool for organi?:ing and remembering what is otheJ;Wise, in James words, ablooming, buzzing confusion.To account for knowledge ofan external thingorevent, accordingly, the naturalistic epistemologist looks rather to the external thing or event itself and thecausal chain of stimulation from it to one's brain. In a paradigm case, light raysare reflected from the object to one's retina activating a.patch ofnerve e n d i n ~ ,each ofwhich initiates a neural impulse to one or another center of the bram.Through intricate processes within the brain, finally, and abetted by imitation o fotherpeopleorby instruction,a cbild comes in t i m ~ to orassentto s?me rudimentary sentenceat theend ofsuch acausal cbain. I callItan observation sentence. Examples are It's cold t It s raining , (I hat s) milk , ( 1 b a t ~ a) d ~ g . .Customarily the experlnientalpsychologist chooses oneor anotheror event, from somewhere along such a causal chain to represent the chain

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.and this he ca s thestimulus. Usually it is aneventofhis own devising. In one ~ n t t will be a flash or a buzz in thesubject svicinity, and inanother itwill bean Ice cube or a shock at the subject's surface. For our more generalpurposes, not linked to any particular e x p e r i m e n ~ an.economical ~ y indefiDing the stimuIusis to inteIcept the causal chains jUst at the subject's sur-face Nothing Is lost, for it Is omy from that pOint Inward that the chains contribute to the subject's knowledge ofthe external world. Indeed evenwhat.reaches thesubject'ssurface isrelevantonly i fit triggersneural receptOrs.'So we might for our purposes simply identify the s u b j e c t ~timulus, over a given briefmoment,with the temporally .orderedsetofsenSory receptors triggered in thatmoment . . . ; .Still further economy might be sought by mtercepting the causal chainsrather at a level- somewherewithin thebrain; foreven thesurface reCeptors that are triggered on any given occasion are largely without relevanteffect on the subject's behavior. However, our knowledge of these deeperlevels s still too sketchy. Moreover, as Jncreaslng1y penetrates these .depths, we become aware of complexity and heterogeneity radicaUy a variancewith theneatsimplicityatthesurface.Each receptor,afterall, admits ofjust two clean-cut states: triggered or no.t .Moreover, the behaviorally inelevant triggerings in aglobal ~ u l ~ canbe defined out anyway, in due course, by appeal to perceptual siJDilarity ofstimuli. The receptorswhose firing is sa ientin a given stimulus are the onesthat it shares with all perceptuallysimilar stimuli. Perceptual ~ itselfcanbe measured, for a given individual, .by reinforcementandextincdonofresponses. th b--- : ulSo it seemsbestfor presentpurposesto construe esu ~ ~ s n usonagiVet1 occasion simply as his global n ~ intakeon that o ccaswn I shaDrefer to it only as neural intake, not stimulus for othernotions ofstimulus arewanted in other studies, particularlywhere d i f f e ~ l 1 t subjects are to get the. same stimulus. Neural intake is private, for subjects do not share receptors.Perceptual similarity, then, isa relation between a subject'sneural intakes.Though testable, it is aprivate affair; the intakesare his and a r e p e ~ p t u a l l ymore or less similar for imPerceptualsimilarity isthebasisofallleaming, allhabitformation, allexpectationby induction from pastexperience; forwe areinnately disposed to expect simDar events to have sequels that are similar toeach other.The association of observation s n ~ with neural intakes is manymany. Any oneof a iange ofperceptually fairly similar intakes mayprompttho subject's assentto anyoneof a range ofsemantically kindred sentences.But in contrast to theprivacy ofneural intakes, and the privacy of theJr ~


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~ p t U a l sUniIarity,observationseiltelicesand their sentaDti


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256 Naturalism: Or, Living Within One's MeaDs 257 express sta1istical trends orprobabilities, which he will take in stride un-less Unexpected results prompt him to reconsider. ,StiU thedeductionandcheckingofobservationcategoricaJs is the essence,,surely, of the experimental method, thehypothetico-deduetive method, 'themethod, in Popper's Words of conjedU e and refutation. tbrings out thatprediction of observable events is the ultimate test of scientific theory.

I sPeakof teSt, not The purposeofscience is to be sought ratherin mteDectual outIOIity and toclmoJogy. In our prehistoric begfnnjnglJ, hoWeve-r, thepurposo tho first gJimmerings ofscientific theory ~ p r c s u m a ~ l yprediction, insofar as purpose can be despiritualized into natural selectionand survivaJ value. Ibis takes us back to ourinnate sense or standard ofperceptualsimilarity and the innate expectation that similars will have mutuallysimilar sequels. In short, primitive induction.Prediction is verbaIized expectation. Conditional expectation, when COl -rect has survival value. Natural selection hasaccordinglyfavored innate stan-datds ofperceptUal similarity that have harmonized with trends in our environment Natural science, finally is conditional expectation hypertrophied.Isaid thatprediction is notthemainpurposeofscience,butonly the test. It,is anegative test atthat,a test byrefutation. As afurther disavowalletme add,contrary to positivism that a sentence does not even need to be testable inorderto qualifyas a respectable sentence ofscience. A sentence is testable, inmy liberalor holistic sense, i adding it to previously accepted sentencesclinches anobservationcategorical thatwas notimpliedbythose'previoussentences alone; butmuch good science is untestable even in this liberal sense. Webelievemany things because they fit in smoothly by analogy, or they symme- triZe andSimplify theoverall design. Sureiy much history and social science is

o this sort and some hard science. Moreover, such acceptations are not idlefancy; their proliferation generates, every here and there, a hypothesis thatcan indeedbetested. Surely this is themajorsoun:eoftestablehypotheses andthe growth o science.The naturalization of epistemology, as I have been sketching it, is both alimitation and a h'beration. The old quest for a foundation for natural science,firmer than science itself, is abandoned: thatmuch is the limitation. The liberation is fiee access to the resources ofnaturaI science, without fear ofcircu-larity. henatu,raUstic epistemologist settles for what he can learn about ,thestrategy, logic, andmechanics by which our elaborate theory of the physicalworld is in factprojected, ormightbe, orshould be, from justthat amorPhous neural intake.Is this sortof tbin still philosophy? Naturalism briDpa salutary blUI'I'iQgof such boundaries. NaturaHstic philosophy is continuous with Il8tural

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s c i ~ c e Itundertakes tocIarify organize,andsimpBfy the broadest andmostbasic:'Concepts, and to analyze scientific method and evidence within theframework of science itself. The boundary between naturalistic philosophyand the rest of science is just a vague matterof degree. . , ' :'Naturalism is naturally associated with physicalism, or materialism. I donot equate them, as witness my earlierremark on Cartesian dualism. Idoembracephysicali m asascientificpoBitioD butI could be dissuaded ofit ODturelJcJendfic groundswithout beJngdissuaded of naturilJam. Quantum mechanics today, indeed, in its neoclassical orCopenhagen interpretation, has adistinctly mentaIistic ring. IMy n ~ t u r a i s m has evidently been boiling down to the claim that in ourpW'Suit of truth about the world we cannot do better than our traditionalscientific procedure, thehypothetico-dedUctive method.,A rebuttal suggestsitselfhere: surelymathematicians. The obvious defense againstthat rebuttal isto say that IIlatb,ematiCal truths are not about ,the world. But this is not adefense ofmy choosing. Inmy view applied mathematics about the world.Thus consider again a case where we are testing a scientific hypothesis byconjoining itto some aIreadyaccepted statements anddeducing an observation'categorical. Likely as not, some ofthose already accepted statements arepurely mathematicaL This is how pure mathematics gets applied. Whateverempirical content those already accepted statements cin claim, then, frombeing needed implying the observation categorical, is,imbibed in particularby the mathematlcaI ones.Thus itis thatIam iodinedtoblurtheboundarybetweenmathematicsandnatural science, no less than the boundary between philosophy and naturalscience. it is r ~ that proved mathematical truths are not subject tosubsequent refutation, my answer is that we safeguard them by choOsing torevoke non-mathematical statements instead, in cases where a set ofments has been found conjointly to imply a false observation categoric8LReaSons can be adduced for doing so; butenough.That l ~ v e s open the vast prolifer8tions ofmathematics that there is nothought orproSPectofapplying. I see these domains as integral ~ our ove.raUtheoryofrealityonly on sufferance: they are expressed in the samesyntaxandlexicon as applicable mathematics, and to exclude them as meaningless by hocgerrymanderingofoursyntax would be thanldess at best. So it is left to usto try to assess thesesentences also as trueorfalse, awe care to.Manyare set-tled by the same laws that settIe applicable mathematics.Forthe rest, I wouldsettIe them as far as practicable by considerations ofeconomy, on a par'withthe decisioDS w m in naturallOionco whon tryingtoframoC mpirJcalhypotheses worthy o ~ t testing.


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258 .W.V.Quine Naturalism; Or. Living Within One s Means 259TraditiolJ81 epistemology was in partnonnativein intent. Naturalistic epistemology in contrast is viewed by Henri Lauener and others as purely desCriptive. I disagree. Just as traditional epistemology on its speculative sidegets naturalized into science or next o kin so on its nonnative side it getsnaturaliZed into technology the teclmology of scientizing.What might e offered first ofan a norm of iJatUtalized epistemology is

pte dietioll observation as a testofa hypothesis. think oftbis as more than anonn: as the name ofthegame. Science cannotanbe tested andthesofterthescience the spatser the tests; but when it is tested the test is predictionof observation. Moteo \7er naturalismhasno special claims ontheprinciple whichis rather the crux of empiricism.. Whatare more distinctively naturaliSticand technological are nOrmJ basedon scientiilcfindings. Thus science has pretty well established subject to fu- disestablishment as always that ourinformation about distant eventsandother people reaches us only through impact of mys and particles onoursensory receptors. A normativecorollary is thatwe shouldbewary ofastrologers palmists and other soothsayers. hinktwice about E.S.P;

. For a richerarrayof norms vague in various degrees we may look to theheuristics of hypothesis: how to think up a hypothesis worth testing. This isWbereCObSidetations of conservatism and simplicity come in and at a more. teclmica11evel probability theory and statistics. n pmctice tbosetechnica1mattersspilloveralso as remarked to complicate the hypothetico-deduc-tive method itself.Isaidat the beginning of this paper thataccording to naturalism it is withinscience itself and not soDie prior philosophy that reality is to bo idontified.Farther along in a more narrowly scientific spirit I speculated o n h ow weround out our recognitionofobjects as objects bitby bit with ouracquisitionof1angU8ge and science. Thesematters can now for somemore broadly p b i ~osophical reflections. . Let:us recall to begin with that the association of observation sentenceswith neural intake is holophrastic. What objects the component words maydesignate in other contexts is irrelevantto theassociation. This is obviouslysoi tho observationsentence is to be acquired as a first step in language leaming; but the associationis equally direct holophrasticin its operation eveni the sentence was acquired through synthesis of its words andgained its immediacy only through subsequent familiarization. .

~ o r e o v e r the specifics of designation and denotation are not only indiffetent to the association of observationsentencei to neural intake; thoyare indlttetellt alSo to the ImpHcatlOl1of obseMlioll categorlca1s by 8 c i e n ~ c ~ ~ ~ory. t is logical implication;andlogic unlike settheory and therest o i u l t l j ~

IDatics responds to no traits of objects beyond sameness and difference. Sowcmust conclude that objects ofanysort :figure only as neutralnodes in t hestructure of scientific theory so far as empiiica1 evidence is concerned. Wecan arbitrarilychange thevalues ofour variables thedesignataof our namesand the denotata of our predicates without disturbing the evidence so longanyWay as the new objects are explicitly correlated one. to onewith the old.Such is the indeterminacy of refere oce as have come to can i t ifirst it is perhaps alarming. We are leftwith no basis it would seem forjudging whether we are talking about famjJjar things or some arbitraryproxies. Theshock subsides however when we reflect on a homely exampleot two. Thus tbiDk ofabody in thescientific framework ofspaceand time. n-sofar as you specify the precise sinuous filament of four-dimensional s p a c e ~time thattbe body takes up in the course ofits career you have fixed theobject. uniquely.We could go farther and i ntify the object a chipmunk perhapswith its portion ofspace tiJne thus saying thatit is atits early endand bigger at its late end. The move is artificial but actually it confers abit ofecon-omy i we are going to have the space timeanyway. Subjective connotationsofbrownness s o f t n e s s ~ swift and erratic movement and the rest simply carryover. Surely all matters of evidenceremajn undisturbed. We are evenpre-pared to say that itwas whut abody was all along an appropriately filled-in.portion ofspace ime as over against empty ones.Next we might identify space time regions in tumwith the sets ofquadrupIes ofnumbers that determinethem insome arbitrarily adopted frame ofea-.ordinates. We cantransfer sensOry connotations now to this abstractmatbo-matical object and still there isno Violence to scientific eVidence. To speak intuitively nothing really happened. .Thuswe can come to terms somewhatwith the indeterminacyof referenceas applied to bodies and other seDSlble substances byjust letting the sensory

connQtations ofthe obserVation sentences cariy over from the old objects totheir proxies.n thecase ofabstractobjectssuch as numbers devoid ofsensoryconnota-tions the indeterminacy of reference is already familiar. It is seen in Frege sso-called Caesar problem: tho DUmborfive may be Julius Caesar. We happilyuse nU Dbers without caring whether they be taken .according to .the Frege-Russell constructions or Ackermann s or von Neumann s. he point was dra-matized long ago F.P. Ramsey with his expediento Ramsey sentences asthey have como to be called. Instoad.QfInvok ing tho.abstract objects spociB wbon QOi ajg ofUlelr propertiea are neoded in IIllfgument the Ramsey

s e n ~ c e Just says that there r objects with thepropenies and then invokest h e ; ~ b j e a s by variables without further identification. This expedient oDly


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.Uv w v J\WIe t llUuraiWD; uri .L.I\ mg Within One'. MOIDJ 261 works forabstractobjects,however, used asauxiliarieshere andthere withoutregard to whether they remain the.sameobjectsfrom OD e context to another~ indetermiDacy of reference can be seen again in its fuJi generality, asDaVidsononce remarked, by ancmnnination ofThrski s cJ8ssical truthdefiDition.1f asentence comes outtrueunder that definition, it continues to do sowhen objects are reassigiledto its predicates in any one-to-one way. .These reflections on ontology are a salutary r e m i n ~ e r that the ultimatedata ofscienceare limited toourneuralintake,andthatthe verynotionofobject, c o n ~ t e or abstract, is ofour own making, along with the rest ofnaturalscience and mathematics. It is our overwhelmingly ingenious apparatus forsystematizing, predictin& and partially controlling our intake, and we maytake pride. ,This conventionalistyiew ofontologyappeals,I expeCt, toHenriLauener.Hein his pragIDatism even settles fora plurality ofscientific specialties, each .with its working ontology, and no dreaID ofan overarcbing, unifying fact ofthe matter. ,Naturalism itself is noncommittal on.this question of unity of science.NatutaJism just sees it as a question.within science. itself, albeit a questionmoreremote from observationalcheckpoints than themostspeculative ques-tions of thehard and soft sciences ordinarily so called. .Naturalism can still.respeet thedrive onthepartofsome ofus, for a uni--tied, an piupose ontology.Thedrive is typicalofthe scientific temper, andofapiecewith thedrive for ~ p l i c i t y that shapes scientifichypotheSes generally.Physicalism is itsamniarmanifestation,and physicalism isbOUnd tohave had. ~ p o r t n t side effects in the framing of morc .pecial hypOtheses in variousbranchesof science; forphysicalismputsaptemiUlilonhypotheses favorableto closer integrationwith physics itself. We have here a conspicuous case ofwhat I touchedonearlier: scientific hypotheses which, thoughnot themselves

testable, help to elicit others that In anyevent,we are now seeingontologyasmore utterlya humanoption.than we used to.We are drawn to Lauener's pragmatism. Must we then conclude that true r e l i ~ is beyondour ken? No, that would beto forsake naturalism. Rather, thenotionof reality is itselfpart of theapparatus; and sticks,stones, atoms, quarks, numbers,and classes all are utterly real denizens ofan. ultimate real world, except insofar as ourpresent sciencemay prove false onfurther testing. . , .What then is natUralism s line on truth and talsity themselves? The tnithptedicate raises no problem in its normal daily use as an instrument ofwhat Jhave called semantic ascent. IBrski s disquotational account accommodates

it, so longas what are calledtrueare sentences in ourown language; an4 we

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th the predicate to sentences of other languages that we accept as~ t o n s of trutbs of our own. However, paradoxes arise when the truthpredicate is applied to sentences. that contain that very predicate or relatedones; so are ca ed upon to recognize ratherahierarchy oftruth predicates,each ofwhich behaves properly onlyin application to sentences that do notcontainthatpredicateitselforhigherones. It is aheirarchyofbetterandbettertruthpredicates butnobest. In practice, eXcept in contextesuch as thesephiJ-osphica1 ones, occasions seldom arisefor venturingabove thefirstrungof theladder. 'liuth olfthe h e i r r c h y b s o l ~ t e truth, would indeedbe transceJident;bringing it down into scientific theory of the world engenders paradOx. Sonaturalism has no plac:e for that..Still, our concept of truth strains at its naturalistic moorings in anotherway. We naturalists say that Science is thehighest path to truth, stiDwe donot say that everythirig onwhich scientists agree is true. 'Nordo we say that .sometbip.g that was true became false when scientists changed their minds.What we say is that theyandwe t ou t it was true, but it wasn't. We havescientistspursuingtruth,notdecreeing it,1i:uththus st8nds forth as anidealofpure reason, inKanfs aptphrase,and transcendentindeed. On this scoreI am

g ~ with Lauener. .C.S. Peirce tried to naturalize truth by identifiying it with'the limit thatscientific progress p p r o c h ~ Thisdepends on optiJnisticassumptions, but w e reconstrueit as metaphor it does epitomize the scientists persistentgive and take of conjecture and refutation. 1i:uthas goal remains the established usage ofthe term, and I acquiesce init as justa vivid metaphorfor ourcontinued adjustment ofourworld picture to our neural intikc. Metaphor isperhapsa handycate oryinwhich toaccommodatetranscendental concepts,from a naturalist pointof view. ' .

Yol. 49, N 2-4 199,

[quine w v] naturalism; or, living within ones mea(bookos.org)

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