The Value of Surprise in Science French Murphyphilsci-archive.pitt.edu/18839/1/The Value of Surprise...
Transcript of The Value of Surprise in Science French Murphyphilsci-archive.pitt.edu/18839/1/The Value of Surprise...
TheValueofSurpriseinScience*
StevenFrench,UniversityofLeeds
AliceMurphy,LMUMunich
ForthcominginErkenntnis
March2021version
AbstractScientificresultsareoftenpresentedas‘surprising’asifthatisagoodthing.Isit?Andifso,
why?Whatisthevalueofsurpriseinscience?Discussionsofsurpriseinsciencehavebeen
limited, but surprise has been used as a way of defending the epistemic privilege of
experiments over simulations. The argument is that while experiments can ‘confound’,
simulationscanmerelysurprise(Morgan2005).Ouraiminthispaperistoshowthatthe
discussion of surprise can be usefully extended to thought experiments and theoretical
derivations.Wearguethatinfocusingonthesefeaturesofscientificpractice,wecanseethat
thesurprise-confoundmentdistinctiondoesnotfullycapturesurpriseinscience.Wesetout
howthoughtexperimentsandtheoreticalderivationscanbringaboutsurprisesthatcanbe
disruptive inaproductiveway, andweendbyexploringhow this linkswith their future
fertility.
Introduction
Scientificresultsareoftenpresentedas‘surprising’,asifthatisagoodthing.Isit?Andif
so, why? What is the value of surprise in science? In addressing such questions
discussions have tended to focus on one of two features of scientific practice: novel
predictionsand their role in the realismdebate (seeHitchcockandSober2004); and
novel or surprising phenomena. In the former case, the surprise associatedwith the
noveltyisdefinitelyagoodthingasfarasthescientificrealistisconcerned,indicativeas
itisofthe‘mindindependent’natureoftherelevanttheory.However,weshallhavelittle
tosayaboutthathere.Inthelatter,thesurpriseisvaluedbecauseitsuggeststhat,given
thecontext,therelevantphenomenonisworthyoffurtherinvestigation.Anexamplehere
*Acknowledgments:We’dliketothankAaronMeskin,JuhaSaatsi,AdrianCurrie,attendeesattheHPSLeedsworkinprogressseminarandtheBristolphilosophyofscienceseminar,andtwoanonymousrefereesfortheirhelpfulcommentsonthispaper.
would be the fogging of Becquerel’s photographic plates, leading to the discovery of
spontaneousradioactivity.Anotherwouldbe thepolarizationof lightby IcelandSpar,
citedbyHacking,togetherwithothersurprisingopticalphenomenasuchasdiffraction,
dispersionandinterference,inhiswell-knowndefenceoftheprecedenceofobservation
overtheory(1983,p.156).However,thespecificsofsuchcasesarealsonotourfocus
here,althoughsuchnovelphenomenawillofferausefulfoiltoourconsiderations.
Ouraiminthispaperistwo-fold:first,weshallshowthatthediscussionofsurprisein
science canbeusefullyextended to include two further featuresof scientificpractice,
namely novel thought experiments and theoretical derivations. We focus on these
becausethoughtexperimentsarealsosaidtogeneratepredictionsandeven,inacertain
sense may be thought of as producing phenomena. More generally, both thought
experimentsandtheoreticalderivationscanbethoughtofasproducing‘outcomes’,just
ascomputersimulationsdo,yettherehasbeenconsiderablylessdiscussionofsurprise
in these cases. Given their central importance to science, there is obvious value in
extendingthediscussioninthisdirection.Furthermore,boththoughtexperimentsand
theoreticalderivationsofferanovelcontext inwhich todiscusssurpriseas theyboth
involve the imagination andmental representations and thereby raise the interesting
question,howcantheyorfeaturesassociatedwiththem,besurprisinginthatcase?We
shallcomebacktothisbelowbutthisthenrelatesdirectlytooursecondoverallaim.1
Thisistouseconsiderationofthesetwoscientificpracticestoputpressureonawell-
known distinction between ‘mere’ surprise and ‘confoundment’, with the former
associatedwiththeoutcomesofmodelsandcomputersimulations,andthelatterwith
novelphenomena(Morgan2005).Thedistinctionisexplicatedinthefollowingterms:a
phenomenonisconfounding,ratherthan‘merely’surprising,ifitis‘bothsurprisingand
unexplainable within the given realm of theory’ (2005, p. 324). Likewise, Ritson
emphasizes the disruptive nature of surprising results and states that ‘the kinds of
noveltyframedasmostvaluablearethosethatviolateexpectationsandaredifficultto
incorporateintoexistingstructuresofknowledge’(2020,p.1).
1We’dliketothankoneoftherefereesforpressingustobeclearerontheseissues.
The outcome of a computer simulation, say, is argued to be only ‘merely’ surprising
because it is ultimately explicable in terms of the theories in terms of which the
simulationwasconstructed.Anysurprise in thatcasemustpresumablybedue to the
scientist’scognitivelimitationswhenitcomestofollowingthestepsofthesimulation,
which may of course be complex. The core idea was captured by Wittgenstein who
dismissedthevalueofsurpriseindeductivecontexts:
"Thedemonstrationhasasurprisingresult!"--Ifyouaresurprised,thenyouhave
notunderstoodityet.Forsurpriseisnotlegitimatehere,asitiswiththeissueof
anexperiment.There--Ishouldliketosay--itispermissibletoyieldtoitscharm;
butnotwhenthesurprisecomestoyouattheendofachainofinference.Forhere
itisonlyasignthatunclarityorsomemisunderstandingstillreigns’(1978,111).
Here,surprisearisesbecauseofpeople’sepistemiclimitations;‘aproofistoolongtokeep
allitsstepsinmind,sosomethingislostfrompurview’(Simons,unpublished;seealso
French and Vickers 2011; French 2020). In such cases, then, the value of surprise is
consideredlessthanthatofconfoundment.
However,weshallarguethatthoughtexperimentsandtheoreticalderivationsmayalso
bedisruptiveofexpectationsandbedifficultto incorporate intoexistingstructuresof
knowledge. Following Currie (2018), we shall call this sense of surprise ‘productive
surprise’ and we suggest that it is more general than ‘confoundment’ whichmay be
retainedforsurpriseassociatedwithnovelphenomena.
WeshallbeginbyoutliningMorgan’sargumentsregardingtheepistemicprivilegingof
experimentsovercomputersimulationsandshallconsidertheminthecontextofthought
experimentsviatwomajorapproachesduetoBrownandNorton.Wedemonstratethat
thought experiments can surprise in a fruitful way, and that this cannot be
straightforwardlydismissedas‘mere’surprise.Thisthenleadsustotheconsiderationof
thenatureandroleofsurpriseinabroadertheoreticalcontextwhichweexplorethrough
theexampleofEinstein’sderivationofE=mc2.HereweshalldrawonMorgan’sclaimthat
aresultisconfoundingifitisinexplicablewithina‘givenrealmoftheory’andshallargue
that a lothingesonwhat countsas the ‘given realmof theory’.Again,witha suitable
choiceofthatrealm,weshallarguethatEinstein’sresultshouldberegardedassurprising
in aproductive senseandwe shall concludeby indicatinghowsuch surprises canbe
understoodasindicativeofacertain‘fertility’possessedbythetheoryconcernedandare
valuableinthatrespect.
1. MereSurpriseandConfoundment
Theuseofcomputersimulationstostudyarangeofcomplexphenomenaiswidespread
throughoutthesciences.Inphilosophyofscience,muchofthediscussionhasconcerned
how they compare with ordinary ‘physical’ experiments. Computer simulations have
beenreferredtoasvirtualexperiments,experiments insilico,orexperimentswithout
materiality.Andsomehaveclaimedthat ‘Simulationmodelling is justanother formof
experimentation’ (Norton and Suppe 2001, p. 92).2 But their status as genuinely
experimental has been contested as they do not intervene in the natural world and
instead, it has been claimed, study ‘hypotheticalworlds’ (Lenhard 2018).Oneway in
whichtherelationbetweenthesetwopracticeshasbeenexploredisthroughMorgan’s
(2005)distinctionbetweenmeresurpriseandconfoundment,originallypresentedvia
the comparison between modelling and experiment in economics. Boumans (2012),
Parke (2014), Currie (2018) and Beisbart (2018) have extended the discussion to
computersimulationsandtheiruseacrossscience.3
Althoughbothsimulationsandexperimentscanachievemeresurprise,onlythelatter,
Morgan argues, can achieve confoundment. This is articulated in terms of the key
differencesbetweentheobjectsofstudyinexperimentscomparedtothoseincomputer
simulations.Thus,Morganlinksthesurpriseargumenttoaclaimaboutthematerialityof
theformer.Bothsimulationsandexperimentsinvolvestudyingasystemthat“standsin”
2Arcangelihasarguedagainstwhatsheseesasthepervasive‘bias’fortheepistemologicalsuperiorityof‘real’experiments,ascomparedwiththoughtexperimentsand‘numerical’experiments(Arcangeli2018).Boydhasalsoarguedthatwhatmattersfortheepistemicutilityofempiricalresultsistheirprovenance(Boyd2018).Withauxiliaryinformationaboutdatagenerationprocessestakenintoaccountanotionof‘enrichedevidence’canbeelaboratedthatencompassessimulations.InthisregardwemightalsomentionDardashtiet.al.(2017)whoarguedthat‘analoguesimulations’mayplayaconfirmatoryroleinastrophysics,forexample.Thanksagaintooneoftherefereesforremindingusofthisfurtherliterature.3AquestiontoconsiderwouldbewhetherMorgan’sclaimsshouldbetakenasspecifictoeconomics,becauseofthecomplexityofpeopleandtheirbehaviour.Here,however,wefollowothersingeneralizingMorgan’sclaim:welosesomegeneralopennesstonaturewhenwesimulate.
forthesystemthatthescientistisultimatelyinterestedin.ButforMorgan,thereisacore
ontologicaldifference;theobjectinanexperimentreplicatespartoftheworlditstands
for (albeit in a way that is simpler tomanipulate), whereas the object of study in a
simulationonlyrepresentstheworldoutsideofthesimulation.4
This ontological difference then underpins that between confoundment and ‘mere’
surpriseviatheissueofcontrol:Asphysicalexperimentsaresaidtocaptureorreproduce
partsofthenaturalworld,theobjectinanexperimentisaversionoftheobjectinnature.
Thismeansscientistsarenotincompletecontroloftheexperiment’sresults.Whereasin
acomputersimulation,scientistsarestudyingsomethingartificialthattheyprogrammed
themselvesandoverwhichthey,ultimately,retaincontrol.
To see this difference, consider surprise in simulations. Scientists are often ignorant
aboutcertainfeaturesoftheirsimulationsandeveniftheyknoweverythingaboutthe
startingassumptionoftheirmodelsandtherulesforhowthesystemwillchangeover
time, these can be very complex, and theywill not know all the consequences of the
conditionsthattheystartedwith.AsMorganhighlights,findingoutwhatfollowsfromthe
initialconditionsisthegoalofrunningthesimulation,andsometimeswhatfollowscan
beunexpected.However,shestates:‘Theconstraintsonthemodel’sbehaviourareset,
however opaque theymay be, by the scientist who built themodel so that however
unexpectedthemodeloutcomes,theycanbetracedbackto,andre-examinedintermsof,
themodel’(Morgan2005,p.325).Thus,asimulation’sresultcanbefullyexplainedbyits
designandimplementation,incorporatingtherelevanttheoreticalpresuppositions.Asa
consequence,itcannotconfound.
4 ForMorgan, this alone has epistemological implications: ‘we aremore justified in claiming to learnsomething about theworld from experiment because theworld and experiment share the same stuff’(2005,p.323,).Therearemanyissueswiththematerialityargument,includingproblemsestablishingwhat“materiallysimilar”actuallyconsistsin(Parke2014)andsomehavesuggesteditisrelevantsimilarity,notmaterial similarity, that is important (Parker 2009). Here, the materiality argument and the surpriseargumentwillbetreatedseparately(asinParke2014).Wetakeitthatwhatisrelevanttothesurpriseclaimisthatinanexperiment,wearestudyingamaterialsystem(notthatwearestudyingasystemthatismateriallysimilar).Thiswouldsuggestthatanaloguesimulationscouldalsoconfound.
Ontheotherhand,whenitcomestophysicalexperimentsthebehaviouroftheobject
underinvestigationisnotcompletelycontrolledbythedesignoftheexperiment,andso
genuinelynewphenomenacanemerge:
‘Such new behaviour patterns, ones that surprise and at first confound the
profession,areonlypossible ifexperimentsaresetupwithacertaindegreeof
freedom…[sothatits]behaviourisnottotallydeterminedbythetheoryinvolved,
norbytherulesoftheexperiment’(Morgan2005,p.324).
Thereis,then,thisimportantconditionof“noover-control”inthecaseofexperiments
thathavethepotentialtoconfoundratherthanmerelysurprise.Inconductingaphysical
experiment,ascientistsetsouttodiscoverhowasystemwillrespondtoanintervention.
Butifthesystemisover-controlled,thenthesystemwillnotbeabletoreactinthisway.
Instead,itsbehaviourisdictatedbythesetupand‘naturedoesn’thaveanythingtosay’
(Beisbert2018,p.187).ThisisincontrasttotheexampleofBecquerelandthefogged
photoplates.
To summariseMorgan’s argument: in a computer simulation, surprising results only
arise becausewe do not have epistemic access to all the consequences of ourmodel
before we run the simulation. But with an experiment, even within the setting of a
laboratorytherecanbe‘potentialforindependentaction’(2005,p.325).Andwhenthere
is,wecanbeconfrontedwithnewphenomenathatare‘unexplainablewithinthegiven
realmoftheory’(ibid,p.324).
Theepistemicvalueofconfoundmentliesinthefactthattherelevantphenomenacryout
forexplanation.Confoundingresultsarethusdisruptiveinaproductiveway:theyforce
ustothinkseriouslyaboutourexistingtheoriesandmotivatenewresearchinorderto
findawayofaccommodatingthesurprisingresults(againseealsoCurrie(2018)and
Ritson (2020)).Wewill now turn to the comparisons between thought experiments,
‘physical’experimentsandcomputersimulationsinordertoconsidertheextenttowhich
thefirstmaybesurprising.5
5Thereisanissuehere,raisedbyoneofthereferees,astowhethersurpriseshouldbeseenasapsychologicalnotionornot;thatis,isitafeelingwehave,orisitanobjectiverelationbetweensome
2. ThoughtExperiments,ExperimentsandComputerSimulations
Whatistherelationshipbetweenthoughtexperimentsand‘physical’experiments?Some
have taken the “experimental” aspect of thought experiments seriously, claiming that
thoughtexperimentsareexperimentsinthesamesenseaslab-basedexperimentsorare
on a continuumwith the latter (see Mach 1896, p. 453). In the design of a thought
experiment,certainfactorsareisolated,variablesarecontrolled,andirrelevantaspects
areidealisedaway.Thesevariablesarethenmanipulatedandtheexperimenter,albeitin
theirimagination,“observes”whatfollows.
SimilarlyforBrown(1986,2007),thatthoughtexperimentstakeplaceinthe“laboratory
ofthemind”doesnotentailthattheyarenotexperimentalinthesamesenseasthose
thattakeplaceinthephysical laboratory.Hearguesthatthoughtexperimentsinvolve
quasi-observationofwhatisessentiallyanabstractsetup;asystemisrepresentedand
thenobservedbythemind’seyeinawaythatisanalogoustoexperiments.6Incontrast,
othershavedrawnasharplinebetweenthoughtexperimentsand‘physical’experiments.
Forexample,forNorton(1991),thoughtexperimentsarejustarguments.Astheywork
byinferencesanddonotinvolveinteractingwith,manipulatingnorobservingthenatural
world,anysimilaritieswith‘physical’experimentsaresuperficial.Weshallreturntoboth
theseaccountsbelow.
There is debate, then, around the relationship between thought experiments and
experiments,muchofwhichiscentredaroundthequestionwhethertheformershould
beclassedwiththelatterorheldasdistinct.Thismakescomputersimulationsahelpful
pointofcomparisonwhenthinkingabouttheepistemologyofthoughtexperimentsgiven
backgroundcommitments,outstandingproblemsandlivemethodologicaloptions?Ourresponseisthatitinvolvesboth:aswetrytoarticulatehere,thesurpriseassociatedwithcertainthoughtexperimentsandtheoreticalderivationsisindicativeoftheirsignificanceandarisesinaspecificcontextthatinvolvesbackgroundcommitmentsetc.butofcourseitmanifests,inboththescientistandtheiraudience,asaspecificfeeling.SeeCurrie(2018)foranaccountofsurpriseasan“epistemicgood”inscience,ratherthanjustapsychologicalfeature.6 Morespecifically,this—thephenomenon,i.e.whatisobservedintheexperiment—iswhatBrownwouldlabelthe“narrow”senseofa(thought)experiment.Experimentsinthebroadsense‘includesthewholethingfromtheoryandbackgroundassumptionstothefinalresult’(2007,158).
that(aswesaw)thereisalsodebateregardingwhethertheycanbeexperimentalinsome
sense. In light of these comparisons, we can now think about Morgan’s surprise-
confoundment distinction in the context of thought experiments. Here we are less
interestedintheidentityquestion—arethoughtexperimentsorcomputersimulations
experiments?Instead,weshallfocusontheissueofprivilegingexperimentsinvirtueof
theircapacitytoconfoundratherthan‘merely’surprise.7
3. SurpriseinThoughtExperiments
WhatdoesMorgan’sdistinctionbetweensurpriseandconfoundmentmeanforthought
experiments?Ononehand,weclearlyknowofexamplesof thoughtexperiments that
haveproducedunexpectedandsignificantoutcomes.TakeEinstein’schasingabeamof
lightexamplewhichexposesthesurprisingtensionsbetweenNewtonianmechanicsand
Maxwell’sequations.Ontheotherhand,thoughtexperiments,likecomputersimulations,
donotinvolveinteractionwiththeworld.Soshouldthesurprisethatarisesfromthought
experiments be dismissed as a less valuable kind as Morgan suggests in the case of
computersimulations?Weshallshowthat,dependingontheaccountofwhatathought
experimentis,therearealternativeviewsastohowtheycansurprise,andwhetherthey
canconfound.WeshallfirstexaminetheissuefromtheperspectiveofBrown’splatonist
view,beforeturningtoNorton’saccount.Wethensuggestanalternativepositionwhich
attendstotherolethattheimaginationplaysinthoughtexperimentsthatdemonstrates
howtheycanbringaboutproductivesurprisesinadistinctiveway.
a) Brown’sView:ThoughtExperimentsandPlatonism
Brownarguesthatthereisasetofthoughtexperimentsthatprovideknowledgeofthe
worldthrough“transcendingempiricism”;theyallowusaccesstothelawsofnaturethat
existasrelationsholdingbetweenuniversals,suchasmass,spinetc.,thataretakentobe
platonicentities.BrownpresentsGalileo’sfamousthoughtexperimentagainstAristotle
7SeeSorensen(1992),Bokulich(2001)andStuart(2016)forfurtherdiscussionsontherelationsbetweenthoughtexperimentsandexperiments.Whilesuchviewsalsohaveimplicationsfortheepistemicstatusofthoughtexperiments,wedonotdiscussthemheregiventhattheydonotfocusonsurprise.
as an illustrative example. This underminesAristotle’s theory that heavier bodies fall
fasterthanlighterones.Galileoasksustoimagineattachingtwoballstogether,aheavy
one and a light one, and dropping them from the leaning tower of Pisa. What does
Aristotle’stheorypredict?Boththatthecombinedbodieswillfallfasterthantheheavier
ballonitsown,asthecombinedobjectisheavier,andthatthecombinedobjectwillfall
slower,asthelighterballisinclinedtofallslowerandso,willdragtheheavierbodyback.
Fromthis,Galileoproposesanewtheory;allobjectsmadeofthesamematerialfallatthe
samespeed.
Brownstatesthathere,‘wehaveatransitionfromonetheorytoanotherwhichisquite
remarkable.Therehasbeennonewempiricalevidence.Theoldtheorywasrationally
believedbeforethethoughtexperiment,butwasshowntobeabsurdbyit.Thethought
experimentestablishedrationalbeliefinanewtheory’(1986,p.10).ForBrown,thisisa
prioriknowledge;thebeliefinGalileo’stheoryisnotbasedonnewempiricaldataand
importantly,neitherisitlogicallyderivablefromolddata(weshallreturntothisbelow
whenwediscussNorton’sview).
WehavealreadyseenthatBrowntakestheanalogybetweenthoughtexperimentsand
physicalexperimentsseriously.Andjustasthelattermayconfoundus,somaytheformer
onthisviewsincethisclassofthoughtexperimentsmayproduceresultsthatcannotbe
tracedbacktoorexplainedintermsoftheinitialconditionsofthethoughtexperiment,
andtheseresultsmaybeinexplicableintermsofthe‘giventheory’.Thus,forBrown,the
insightswegainfromplatonicthoughtexperimentsarenotsimplyamatterof‘seeingold
empiricaldata inanewway’ (ibid.,p.11)butrather, involvegenuinediscovery.Here,
then, we see how thought experiments may confound, at least on a ‘platonic’
interpretation.Ofcourse,thatinterpretationcomeswithacertainontologicalcostand
onemightprefertoavoidthatbyadoptingamoreminimalistapproachtowhichweshall
nowturn.
b) Norton’sView:ThoughtExperimentsareArguments
This alternative view takes thought experiments to be arguments. In answering the
questionofhowtheycanhavenovelempiricalimportNortonclaimsthatthereis‘only
onenon-controversialsourcefromwhichthisinformationcancome:itiselicitedfrom
informationwealreadyhavebyanidentifiableargument…Thealternativetothisviewis
tosupposethatthoughtexperimentsprovidesomenewandevenmysteriousrouteto
knowledgeofthephysicalworld’(1991,p.129).
Norton’sviewmaybeseparatedintotwoclaims.Thefirstisareconstructionthesis:The
epistemicpowerofathoughtexperimentisthatofitsreconstructedargumentform.The
secondclaimisabouttheperformanceofathoughtexperiment:theconductofathought
experimentjustisthatofanargument.
Revisiting Galileo’s thought experiment, it can be reconstructed as an argument
(uncoveringaninconsistencyinAristotle’sphysics)asfollows:
(i) Naturalspeedisdirectlyproportionaltoweight
(ii) Weightisadditive
(iii) Naturalspeedismediative
From(ii)and(iii),wegetthenegationof(i)8
BeisbartandNorton(2012)andBeisbart (2012)claimthatcomputersimulationsare
alsoarguments.The thought is thatcomputersimulationsraiseaparallel issue to the
abovequestion:howdotheyprovideknowledgeaboutareal-worldtargetwithoutany
observation of that target? Their answer is that thought experiments and computer
simulations provide knowledge in the sameway: we build what we know into their
construction,thatis,thedescriptionofthethoughtexperimentortheassumptionsofthe
computersimulation,andthisknowledgeisthentransformedthroughalogicalprocess.
Thus, computer simulations can also be reconstructed into arguments, and their
epistemic force is not thereby lost. And further, that ‘the reconstructing argument is
executedwhenacomputersimulation iscarriedout’ (Beisbart2012,p.419-420).We
shallnotconsiderfurtherthisviewherebutwewillcomebacktosomeoftheworriesof
theargumentviewwhenappliedtothoughtexperiments.
8 Norton’s reconstruction is limited to the “destructive” part of Galileo’s thought experiment and does not include the step that is central to Brown’s platonism view, i.e. the introduction of the new theory that all bodies fall at the same speed. This is because, Norton argues, the move involves a problematic assumption, namely that the ‘speed of fall of bodies depends only on their weights’ (1996, 342).
Now, on this view of thought experiments, do they ‘merely’ surprise or can they
confound?BeisbartandNortondonotdenythatwegainnewknowledgefromthought
experiments(andcomputersimulations)as‘theresultsinferredwerenotknownprior
toinvestigations’(2012,p.409).However,theydrawadistinctionbetween‘discovery’,
as in thecaseofphysicalexperimentsand ‘inferring’as inthesecases,wherethought
experimentscanbearticulated in termsof inferencesdrawn fromwhat is implicit. In
Galileo’s thoughtexperiment, the contradiction inAristotelianphysicswasalready, in
somesense“there”;thethoughtexperimentquaargumentsimplyexposedit.
However,reductioargumentssuchasthisarepragmaticallyawkwardinthatthereader
isinvitedtoassumethatwhichissubsequentlyshowntobefalse.Ifwetakethisinitial
assumptionorpremise,thatis,(i)intheabovereconstruction,asthe‘giventheory’inthe
characterisationofconfoundment,thenofcoursetheconclusion,thatthe‘giventheory’
isfalse,cannotbeexplainedintermsofthatverytheory(atleastnotonmostaccountsof
explanation).However, if the ‘given theory’ is expanded to include theargument as a
whole,thenclearlytheconclusionisexplicable–we’vejustgivenanargumentforit!In
terms of this ‘argumentative’ characterisation, then, thought experiments such as
Galileo’smaysurprisebuttheydonotconfound.
HerewerecallWittgenstein’sdismissalofthevalueofsurpriseindeductivecontextson
thegroundsthatthecauseofthesurprisehastodowithscientists’cognitivelimitations.
Ifweweretofollowthisline,alongwithNorton’spresentationofthoughtexperiments
asarguments,thentheremightseemtobelittleofanyinteresttosayaboutsurprisein
this context.9 However, it is important to note that Norton’s reconstructions are not
limitedtodeductivearguments;theycanalsoincludeinductivesteps,asintheexample
ofEinstein’selevator10;‘thecaseistypicalandwillholdforallobservablephenomena’
9FrenchandVickers(2011)introducethistounderminePopper’sviewthatsurprisemotivatesarealistview of theories. Again, we come back to connections between surprise in theories and thoughtexperimentsinsection4.10Einsteinimaginedsomeoneperformingexperiments,suchasthrowingaballandobservingitstrajectory,inanelevatorthatwasacceleratingupwards.Herealisedthattheobservationsmadewouldbeexactlyasiftheelevatorwereinagravitationalfield,concludingthattheprincipleofrelativityshouldbeextendedtoincludeacceleratingframesofreference.ThisthoughtexperimentthusplayedafundamentalroleinthedevelopmentoftheGeneralTheoryofRelativity.Whatitbringsintothelightistheequivalencebetweeninertial and gravitational mass which had been noted by Newton but which Einstein elevated into afundamentalprinciple.
(1991,p.137).11Andso,Norton’sviewofthoughtexperimentsallowforstepsthatare
ampliative;theygobeyondwhatisstatedinthepremises.12Thesameholdstooforhis
and Beisbert’s account of computer simulations, these can also transform the
assumptionsinthemodelinawaythatpreservestheprobabilityoftruth(2012,p.411).
Nevertheless,onNortonandBeisbart’sview,theinformationwegainthroughdeductive
and inductive inferences does not constitute genuine discovery as in the case of
experiments(2012,409).AndBeisbart(2012,2018)hasexplicitlyendorsedMorgan’s
accountwhendiscussingtheepistemicstatusofsimulations,offeringtheexampleofthe
Michaelson-Morleyexperiment (1887) thatundermined theview that theearthhasa
non-zerovelocitywithrespecttotheether.AsBeisbartargues, thisexperiment ‘hasa
complicated set-up, and a number of assumptions are needed to interpret its data as
having implications about the ether. But this does not imply what the result of the
experimentis’.Ifinstead,asimulationwasused,itwouldnothaveconfoundedasthere
wouldbeanassumptionregardingtheearth’svelocitywithrespecttotheetherinthe
simulation’sprogramming(Beisbart2018,12).13
Despitethis,Currie(2018)andParke(2014)giveexamplesofsimulationsthatproduce
results that go against expectations and ‘promote changes to, or re-examinations of,
explanatoryresourcespertainingtothetarget’(Currie2018,p.654).14Wehaveindicated
11Norton’snotionoflogicalreasoninginthoughtexperimentshasexpandedovertheyearstoincludestepsbeyonddeductionandinductiontoinformalinferencesandreasoningfromanalogy.Thishasbeentakentorendertheargumentaccount‘vacuouslytrue’(Brendel2018,p.287).12Thisampliativefeaturemaysuggestthatinductioncanleadtodiscoveriesorgeneratesurprisesbeyond‘meresurprise’,anditwouldbeinterestingtothinkmoreaboutthisinthecontextofanargumentviewofthoughtexperiments.However,considerenumerativeinductionforexample:afterobservingmanywhiteswansundervariousconditions,ithardlyseemssurprisingthatthenextswanIseeiswhite.Perhapsthenitistheuniversalgeneralisation‘Allswansarewhite’thatismeanttocomeasasurprise,butagaingiventhatthiswouldhavebeenformulatedafterobservingnumerousswansundervariedconditions,thatseemsimplausible.Whatmightseemasurpriseisifthegeneralisationholds,unfalsified,evenwhenthefieldisgreatlyenlarged(toincludeAustralia,say)butthenonemightexpectthatfeelingofsurprisetodissipateasscientistsofferanexplanationastowhythegeneralisationhastohold,forfundamentalbiologicalreasons.Again,wearegratefultoarefereeforraisingthisissue.13Further,wecanconsidercasesofthoughtexperimentsthatmaybringaboutmeresurprise(inthesenseofanunexpectedconsequence)butdonotconfound.Oneexample,discussedbyBokulich(2001),istherocketsandthreadthoughtexperiment,whichdrawsoutaphysicalimplicationofspecialrelativity(belowweshallconsideranimplicationofthetheorythatweclaimcanberegardedasproductiveinawaythatsuggeststhedistinctionbetween‘mere’surpriseandconfoundmentistoocoarse-grained).14 Importantly,theyeachgiveexamplesofsimulationswhich,theyargue,canconfoundinMorgan’ssense.ParkepresentstheexampleoftheABMSugarscapewhichhad“hiddenfeatures”thatwererevealedinthesimulation(2014,531).Currieoutlinesasimulationofsauropods’gait.Theresultwas
above how the issue of whether thought experiments confound, rather than merely
surprise,maydependonhowtheyarecharacterised.However,what is crucial is that
evenwhenpresentedintheformofanargument,theycanbedisruptiveinthesenseof
forcing us to re-evaluate our existing theories. Indeed, for many such thought
experimentsthisistheirprincipalroleanditisobviouslythecaseinthereconstruction
ofGalileo’sthoughtexperiment,where,althoughtherearenonewempiricaldiscoveries
beingmade,thescenarioweareaskedtoimagineexposesacontradictioninAristotelian
physicsandsubsequentlypromptsthedevelopmentofanewtheory.15Takentogether,
theseconclusionsputpressureonMorgan’sclaimthatthedifferentsourcesofsurprise
impacttheepistemicstatusofthefeatureunderconsideration.
Havingsaidthat,weagreethatthereisadifferencebetweenthoughtexperimentsand
computersimulationsontheonehand,andexperimentsontheother,inthatthesurprise
arises inadifferentway.So,topursuethecomparisonfurther,werecall thatphysical
experimentscanresultinnewempiricalresultsthatmayforceustoreviseourtheoretical
knowledge. Simulationsdiffer in thatdesigning and running a simulation is away ‘of
fillingout,makingexplicit,andprobingourtheoretical,conceptualandempiricalideas’
(Currie2018,p.656).Thisisstillawayofgeneratingknowledge(andcanbringabout
productivesurprises) butunliketheexperimentcase, itdoesnotinvolvethis ‘contact
withnewempiricalresults’(ibid).Likewise,thoughtexperimentsprobeourtheoretical,
conceptual and empirical ideas. However, there are important differences between
thought experiments and computer simulationswhich illustrate how they probe this
knowledgeindifferentways.Andthishasimplicationsforhowtheformerbringabout
productivesurprises.
c) Thoughtexperimentsandtheimagination
In order to explore those differences, let us begin with the view that computer
simulations are simply more complex thought experiments. Di Paolo et al (2000)
unexpectedandpromptedtheinvestigatorstoreflectontheexplanatoryresourcesofthetarget(2018,654).15AccordingtoFeyerabend(1975,pp.73ff;seealsoArthur1999,pp.220-227)Galileoofferedanew‘naturalinterpretation’ofthephenomenonallowinghimtobringtheCopernicanviewintoconsonancewiththefactsthatapparentlyrefutedit.
characterise simulations as ‘opaque’ thought experiments, and Lenhard (2018) has
arguedthatduetotheircomplexityandopacity,theformeraremorelikelytosurprise
thanthelatter.16
Althoughitmayseemthatsimulationsaremoretransparentinthattheyworkbyalarge
numberofsimplesteps,whatLenhardmeansisthatthoughtexperiments‘havetomeet
high standards of intelligibility, because the whole process takes place in cognition’
whereas in a computer simulation, ‘it is the multitude of interrelated steps that can
rendertheoverallprocessopaque’(2018,p.485).Ifwetakehimtomeanmeresurprise,
asopposedtoconfoundment,thenhisclaimisthatwearemorelikelytogetsurprising
behaviours (someofwhichmaybeproductive) fromcomputersimulations than from
thoughtexperiments,asthelatterare“transparent”inawaythattheformerarenot.17
However, characterising computer simulations as more complex or opaque thought
experiments misses something important about the latter. Firstly, part of what is
surprisingaboutthoughtexperimentsistheirsimplicity.Thereissomethingsurprising
inGalileo’s thought experiment that it had such significance in thehistoryof science,
despite being a simple imagined scenario, involving the behaviour of bodies being
dropped from a tower.18 We shall come back to this in the context of theoretical
derivations.
Secondly,wecansee,byattendingtotheroleofimagination,thatthoughtexperiments
canbringaboutsurpriseinadistinctiveway.Itjustisnotobviouslythecasethatwehave
clearaccess toour imaginingsand theconnectionsbetween them,andhence thought
experiments cannotbe characterisedas straightforwardlyas thisviewpresupposes.19
16StuartandNersessian(2019)alsodiscussthedifferentwaysinwhichscientistscanlackaccesstotheircomputermodel,andtheyarguethatvisualisationscanbecreatedtoreduceepistemicopacity.17SeeLehnard(2019)forhismoredetailedviewonsurpriseinsimulations. 18Ofcourse,thesurprisegeneratedbysuchthoughtexperimentsmayvaryaccordingtotherelevantscientific(andperhapsmorebroadly,social)context.Havingsaidthat,itisoftendifficulttodiscoverhowsurprisedscientists–muchless,generalreaders–wereuponbeingpresentedwithone,particularlyinearliercenturies,giventhatthisreactionwastypicallynotrecorded(foranexampleofamodernexpressionofsurpriseovercertainfeaturesoftheoreticalphysics,seePeierls1979).Again,ourthankstooneoftherefereesforremindingusofthisissue.19TheWittgensteiniandismissalofsurpriseindeductionscanbelinkedtohisclaimthattheimaginationcannotprovideuswithnewinformationbecauseitissubjecttothewill(whereas‘real’objectsarenot)(1980,§80).Similarly,Whitestates‘onecan’tbesurprisedbythefeaturesofwhatoneimagines,sinceoneputthemthere’(1992,92).Stock(2007)andTodd(2020)haveofferedadetailedresponsetosuch
Thus, returning to Galileo’s thought experiment, Gendler has argued that, contra to
Norton’s account, it is not straightforward to conclude that Aristotelian physics is
inconsistent, since it is unclear whether all the propositions in the reconstructed
argumentformoughttobeconsideredpartofAristotle’stheory.Inparticular,ithasbeen
askedwhyweshouldconsider(iii)aspartofthetheory—thatnaturalspeedismediative,
ormorespecificallythat ‘NaturalspeedisapropertysuchthatifabodyAhasnatural
speed1,andabodyBhasnaturalspeed2,thenaturalspeedofthecombinedbodyA-B
willfallbetween1and2’(1998,p.404).Withoutthisassumption,theinconsistencyclaim
isunfounded.
Asaresult,therearevariouslogicallypossiblewaysoutfortheAristotelian.Forexample,
theycanask—arethebodiesthataretiedtogetheroneobjectortwo?Ifoneobject,then
itwillfallatthespeedthatisproportionaltothecombinedweight.20Gendlercontends
that thethoughtexperiment is indispensableandcannotbereconstructed inNorton’s
sensewithoutlosingitsdemonstrativeforce.21Thissuggeststhattheimaginationallows
kinds of jumps that cannot be accommodated within the framework of more formal
reasoning.22Understandingthoughtexperimentsasargumentsthusfailstofullycapture
theirpotentialtoproductivelysurprise,afeaturethatcharacterizes,atleastinpart,their
roleinscientificpractice.23
Our conclusion, then, is that thought experiments open up space for a discussion of
surprise that is more nuanced than a classification into either ‘mere’ surprise or
claims,andseealsoKind(2018)andEgeland(2019)fordiscussionsofhowwecangainnewinformationfromtheimagination.20Indeed,ithasbeenarguedthatanAristoteliancouldhavechosenthisoption—thereisnocommitmentatthistimeonthisissue(seeVickers(2013,p.196)). 21ForGendler,Galileo’srejectionoftheAristotelianview,andthe“blocking”oftheAristotelian“waysout”(whenthethoughtexperimentispresentedinitsnon-argumentform)isjustifiedbecauseittapsintoourpreviouslyunarticulatedknowledgeoftheworld(1998,407).Inthissense,heraccountdeniestheclaimthatimaginingsaresolelyconstitutedbythepersonwhoisimagining(whichwaskeytoWittgenstein’sscepticism)sincethebackgroundbeliefsthatcontributetotheimaginingcomefromtheimaginer’sexperienceoftheworld,ratherthansolelyfromtheimaginerthemselves.Stock(2007)alsodiscusseshowimaginingsarepartlyinformedbybeliefsabouttheworld.22Itisoftenhighlightedthattheimaginationhastobeappropriatelyconstrainedifitistoprovideinsightsabouttheworld.Whatweemphasisehereisnotthattheimaginationistotallyunconstrainedwhenitisfruitfulinscience,butratherthatitcanallowforreasoningthatislessrestrictivethanthatinargumentsorcomputersimulations(seealsoStuart,2020).23Focusingonimaginationallowsustocapturethissenseofsurprisewithoutcommittingtoaplatonicviewofthoughtexperiments.
confoundment.Certainly,theproductivenatureofthesurprisetheyengendersuggests
thattheformerlabelisinadequate,whereastherequirementofinexplicabilityinterms
ofthe‘giventheory’associatedwiththelatterclearlyneedstobehandledcarefully.With
thatinmind,letusnowturntoafurtherscientificarenainwhichsurprisecanarise,that
oftheoreticalderivations.
4. TheoreticalSurprise
ConsiderEinstein’sderivationofE=mc2whichPoppersubsequentlydeclaredmusthave
comeasasurprisetohim(1978,p.162).24Herethesurpriseisnotthatassociatedwith
discoveringthatapredictionturnsouttobecorrect;thatis,itisnotthekindofsurprise
associatedwithnovelpredictions.Rather,thesurpriseisassociatedwiththetheoretical
derivationitself,priortoanyconfirmationofatheoreticalprediction,whichinthiscase
hadtodowiththediscoveryofnuclearfission.ForPopper, theepistemicvalueofthe
surpriseinthiscaseseemstohavebeenthesameasthatofBecquerelbeingsurprisedat
hisphotographicplatesbeingfogged.25Thatis,justas‘material’realitymaysurpriseus,
socantheories, leadingPoppertofamouslylocatetheminhisWorldThree,or, ‘…the
worldofintelligibles,or…theworldoftheoriesinthemselves,andtheirlogicalrelations
…’(Popper1972,p.154).
Ifwetakethese‘intelligibles’asabstractentities,insomesense(seeFrench2020,Ch.5)
wecandrawaclearcomparisonwithBrown’sviewofthoughtexperiments,asdiscussed
above.Indeed,Popperinsiststhattheorieshaveapropertythatonlyexistingthingscould
have:thiselementofsurprise.Hetakesthistobeamarkoftherealityofsomething:just
as physical objects surprise us aswe discovermore about them, so too do scientific
theories.
24Ithasbeenquestionedwhetherthisissuchanappositeexample,given,ithasbeenclaimed,thattheexactmeaningofthisequationiscontentious.Whetherornotthatisthecase(andwethinknot),thisisaclearlysignificantresultaboutwhichsurprisehasbeenexpressedandwhichalsoexemplifiescertainfeaturesthatwewishtofocusonhere. 25BedessemandRuphy(2019)givetheBecquerelcaseasanexampleof‘scientificunpredictability’,inthesense of ‘the occurrence of unexpected results in the course of the inquiry that open up new lines ofresearchanddiscoveries.’(ibid.,p.3).Ofcourse,Becquerelwasalready‘primed’,asitwere,tomakesuchadiscovery,givenhisinterestinphosphorescenceandfollowingthediscoveryofx-raysbyRöntgen.
Onecouldmaintainthatthisisacaseof‘mere’surpriseandinsist,alongWittgensteinian
lines,thatthereasonswhypeoplearesurprisedbysuchtheoreticalimplicationsliein
theircognitivelimitations.Inotherwords,ifEinsteinwassurpriseditwasonlybecause
notevenhewaslogicallyomniscient.However,eventhisdoesnotmeanthatithasno
epistemicvirtueaswesawinthecaseofregardingthoughtexperimentsasarguments.
Beforeweconsiderthatpoint,itisworthnoting,however,thattheWittgensteinianline
appearstofalterinthiscase,simplybecauseEinstein’sproofisfamouslynotthatlong,
withtheentirepaperrunningforonlythreepages.
Einstein begins bynoting that ‘[t]he results of the previous investigation [namely his
papersettingoutthebasisofSpecialRelativity]leadtoaveryinterestingconclusion…’,
anopeningsentencethatmayindeedindicatehissurpriseattheresult.Hetheninvokes
Maxwell’sequations,which,ashenotes ina footnote, incorporate theprincipleof the
constancyof thespeedof light,and theprincipleof relativityandapplies themto the
situationinwhichwehaveanextendedbodyemittingapairoflightpulsesinopposite
directions,effectivelyoutlininganotherthoughtexperiment.26
Einsteinthenconsidersthechangeintranslationalkineticenergyofthebodyasaresult
ofemitting the lightpulses.Theproblemis, theexpression for thekineticenergyofa
particle isnotstraightforwardlyextendable to thatofanextendedbody inrelativistic
physics.So,Einsteindefinedthekineticenergyofsuchabodymovingwithspeedvina
giveninertialreferenceframeasthedifferencebetweentheenergyofthebodyinthat
referenceframeanditsenergyinaninertialreferenceframeinwhichitisatrest(see
Ohanian2009, p. 168).With this at hand, he could then obtain an expression for the
changeinkineticenergyofthebodywhenitemitsthepulsesoflightinitsrestframe,as
observed from amoving frame. Finally, he took the low-speed approximation of the
energy,byneglectingmagnitudesoffourthandhigherorders,andsubstitutingthatinhis
expressionheobtained,inmodernform,E=mc2.Interestingly,givenwhatwastocome,
he concluded with the speculation that ‘It is not impossible that with bodies whose
energy-content isvariabletoahighdegree(e.g.withradiumsalts) thetheorymaybe
successfully put to the test’ (1905 p. 3). On theWittgensteinian approach,wewould
26Thus,wemightviewthiscaseasakindofhybridofthesortofthoughtexperimentsexaminedaboveanda‘pure’theoreticalderivation.
expectshort,simplederivationstobeunsurprising.Thus,giventhebrevityandapparent
simplicity of the derivation, this approach cannot account for the surprise felt over
Einstein’sresult.27
Why,then,wouldEinstein,oranyoneelse,havebeensurprised,asPoppersuggests?
Thequestionbecomesevenmoreacuteonceitisacknowledgedthatsomerelationship
betweenmassandenergywaswell-knownatthetimeinthecontextofelectromagnetic
radiation.ThelikesofHeaviside,AbrahamandLorentz,amongothers,all investigated
howthemassofachargedobjectchangesinanelectromagneticfield,yieldingthenotion
of‘electromagneticmass’,withHasenöhrlderivingtheexpressionE=(4/3)mc2.Poincaré
(who together with Lorentz is famously associated with the ‘discovery’ of Special
Relativity)didexpressanattitudeofsurpriseinthiscontext,butassociateditwiththe
conclusionthatifmass,asan‘essentialpropertyofmatter’isreducibletoenergyinthis
manner,thenmatteritselfcannotbesaidtoexist (Poincaré1906).
PerhapstheanswertoourquestionliesintheobservationthatEinstein’sresultreplaced
the above line of research with the relationship between E=mc2 and more general
principleshavingtodowiththenatureofspaceandtime(somethingdrivenhomeby
Minkowski’s ‘reformulation’ofthetheory).Inthatcasethesurpriseisassociatedwith
theestablishmentofsucharelationshipbetweenanalreadyknownresult(broadlyand
grantedthedifferenceinnumericalfactor)andthesegeneralprinciplesthateventually
cametobeappreciatedasunderpinningaverydifferentviewoftheworld.28Theanswer,
then,toPopper’squestionisthatEinsteinwasthefirsttoobtainthatrelationship.
Certainly, many years later, Meitner recalled her own surprise over Einstein’s result
whenhepresenteditinatalkinSalzburgin1909,writing:
‘AtthattimeIdidnotrealisethefullimplicationsofthetheoryofrelativityandthe
wayitwouldcontributetoarevolutionarytransformationofourconceptsoftimeand
space.Inthecourseofthislecturehedid,however,takethetheoryofrelativityand
27 Havingsaidthat,thederivationisflawed(foranoverview,seeOhanian2009). 28WearegratefultoAaronMeskinforacoffeehouseconversationonthisissue.
fromitderivetheequation:energy=masstimesthesquareofthevelocityoflightand
showedthattoeveryradiationmustbeattributedaninertmass.Thesetwofactswere
sooverwhelminglynewandsurprisingthat,tothisday,Irememberthelecturevery
well’(Meitner1964,p.4;seealsoRife2019andSime1997,p.39)29
Meitner,ofcourse,togetherwithOttoFrisch,subsequentlyusedtheformulatoexplain
nuclearfission,makinggoodonEinstein’sobservationinthepenultimatelineofhis1905
paperasindicatedabove.
Granted, then, the surprise associated with Einstein’s result, what is its epistemic
significance, if any?Again,wehave to take carewhen it comes to the requirementof
inexplicabilityinthecontextofagiventheory.IfthatistakentobeSpecialRelativityitself,
thenclearlytheresult,beingderivedfromthattheory,isnotinexplicableintermsofit!
However, the above historical considerations suggest that we should take the ‘given
theory’ to be the classical ‘electromagnetic worldview’ of the time, with any
confoundment,inMorgan’ssense,associatedwiththeestablishment,inthatcontext,of
thederivationof the relationshipbetweenenergyandmass– somesuch relationship
havingalreadybeenposited–fromafundamentalreconceptualizationofspaceandtime.
Furthermore,asinthecaseofthoughtexperiments,reflectingonthesurpriseassociated
withsuchtheoreticalderivationssuggeststhatitshouldbecharacterizedas‘productive’.
Inthenextsectionweshallconsiderhowthisformofsurprisemightbesituatedwithin
anappropriateepistemicframework.
5. SurpriseandTheoreticalFertility
ConsideragaintheexampleofBecquerel’sdiscovery:notonlywasitdisruptive,inaway
thatmightbepartially,atleast,capturedbythenotionof‘confoundment’butitwasalso
fruitful.Itwasdisruptiveinthatitoverturnedexistingaccountsofradiativephenomena
and,ultimatelyofcourse,itcontributedtotheoverturningofclassicalphysics;anditwas
29 It has been suggested that what surprised Meitner were the technological implications of the result. However, granted that she is recalling her past surprise, this does not seem plausible given that such implications were not apparent in 1909.
also,clearlyandrelatedly,immenselyfruitful,withBecquerelhimselfpublishingseven
papersonthephenomenonimmediatelyafterwards,initiatinganintenseprogrammeof
researchinvolvingtheCuriesandmanyothers,ofcourse.Jumpingaheadover120years,
followinghersurveyofscientistsworkingattheLargeHadronCollider,Ritsonconcluded
that‘Thekindsofnoveltyframedasmostvaluablearethosethatviolateexpectationsand
aredifficulttoincorporateintotheexistingstructuresofknowledge.Insuchinstances,
disruptiontotheexistingontologyorwaysofknowingwerevalued’(2020,p.2).30
In this case, involving the discovery of novel properties of particles, she argues that
scientistscashoutthevalueofsuchnovelresultsintermsofindicatingadirectionfor
future research: ‘This appraisal that potentially theoretically unexpected results can
provide future fertility helps us to begin to understand how results that contradict
expectationscanbevalued.’ (ibid.,p.7).Thus,Ritsonargues, thepositiveappraisalof
disruption is based on forward looking assessments of future fertility, or forms of
heuristicappraisal.Shenotes,inparticular,thecommentsofscientistswhoareeffusive
in their assessment of the fertility of a disruptive result because it would point
researchersinthedirectionoffutureresultsthatmightaccommodatethedisruption.
Here,contradictingexpectationsmightbeunderstoodasgoingbeyondbeinginexplicable
in terms of a given theory and in this sense, being disruptive is broader than
confoundment.Theinterchangeabilityofmassandenergyisappropriatelycharacterised
as disruptive in this sense and, as expressed by Einstein, was also fertile in that it
indicatedthedirectionoffutureresearch.Thissenseof‘futurefertility’wascapturedby
Peirce with the phrase ‘esperable uberty’, applied to the ‘hoped for’ ‘fruitfulness’ or
‘fertility’ of scientific theories (see French 1995). Peirce himself characterised this in
termsofbeing‘gravidwithyoungtruth’(1913).
30Asoneoftherefereeshasremindedus,weshouldbecarefulnottogeneralisetoofarfromthiscasestudyastheremaybeexamplesofresultsthataresurprisingbutarenotdisruptive.OnesuchthathasbeensuggestedistherecentcaseoftheGoogleDeepMind‘AlphaFold’proteinfoldingalgorithmthatcanapparentlyaccuratelypredictmanyproteinstructuresfromtheiramino-acidsequence.However,manycommentatorshaveemphasisedthatthisdoesnotsolvethe‘protein-foldingproblem’insofarasnoexplanationisgivenforthestructuresobtainedandinthatrespectthisisnotacaseoftheoreticalderivation,whichiswhatwe’reinterestedin(see,forexample,Ball2020).
Thequestionthennaturallyarises,onwhatbasismightwetakesuchfertilityinatheory
tobe‘hopedfor’?Andfurther,howmightweevaluatewhetheragiventheoryismoreor
lessfruitfulthanothers?Wesuggestthatthesurpriseevincedbycertainconsequences
ofthetheoryisonewayofdeterminingits‘esperableuberty’.
ThisseemsevidentinthecaseofE=mc2,particularlygiventhattherelationshipbetween
mass and energy had already been noted in the special case of the electromagnetic
context.That itcouldbegeneralisedthroughbeingderivedfromthetheoryofSpecial
Relativityisindicativeofthewaythattheorycanberegardedas‘gravidwithyoungtruth’.
AndthehopethatitwouldbefruitfulwasthenconfirmedbyMeitnerandFrisch’sresult.
Recent discussions of the value of such theoretical fertility have been shaped by
McMullin’s (1976) distinction between fertility in terms of the actual success that a
theoryhasinopeningupnewavenues,dealingwithproblemsandanomalies,etc.,which
hecalls‘proven’orP-fertility;andfertilityinthesenseofdesignatingthepotentialofa
theory for future development,which he calls ‘untested’ orU-fertility. The former, of
course,isretrospective,andisassociatedwiththeepistemicappraisalofatheory,being
indicativeofsomedegreeof‘fit’,again,betweenthetheoryandtherelevantsystem(ibid.,
p.264),whereasthelatterisassociatedwithitsheuristicappraisal.
InthecaseofE=mc2,weseemtohaveanobviouscaseofamovefrom‘U-fertility’in1905,
or1909inMeitner’scase,to‘P-fertility’in1939,thetheory’sfertilitybeing‘proven’by
thediscoveryofnuclearfission.Note,however,thatitisnotacaseofovercomingsome
anomaly,asMcMullinhasit,butratherthatoffertilitymanifestedintermsofa‘newand
powerful’extensionofthetheoryofrelativity.However,ifU-fertilityistakentohaveonly
heuristicvaluethenitandthesurpriseassociatedwiththetheoreticalentailmentprior
toitsconfirmationandshifttoP-fertilitymightappeartohavenoepistemicvalueatall
(seeNolan1999).However,thisignoresthe‘esperable’orhopedforaspect.Werecall,
again, that although the extension of Einstein’s theorywas ‘new’ andhencemight be
regardedastheoccasionforsurprise,therelevantphenomenon,generallycharacterized,
wasnotentirelynovel.Aswehavesaid,thissuppliedgroundsforhopethatthetheory
was indeed fertile. And this in turn suggests that, as with ‘mere’ surprise and
confoundmentweneedtomovebeyondMcMullin’sclassification,atleasttosomedegree.
Consider:the‘potential’thatatheoryhasforfurtherdevelopmentmaybefarranging,
covering all sorts of possibilities, from the trivial to the implausible. How shouldwe
determinewhichareindicativeofthetheorybeing‘gravidwithyoungtruth?Disruptive
surprisemayactasa‘flag’insuchcases.Einstein’stheoryofSpecialRelativitywas‘U-
fertile’inallsortsofways,ofcourse;anditsP-fertilitywas(eventually)demonstrable.
ButwhatMcMullin’sdistinctionfailstocaptureisthe ‘esperable’orhopedforfertility
markedbythekindsofexpressionsofsurprisewehavenotedhere.Thus,thisexample
nicelyillustratesthatthedivisionbetweenheuristicandepistemicappraisalmaynotbe
ascleanassomemighthope(seealsodaCostaandFrench2003,Ch.6).31
6. Conclusion:TheDisruptiveNatureofSurprise
We began by considering Morgan’s distinction between ‘mere’ surprise and
confoundment,wherethelatterisdistinguishedfromtheformerbyvirtueoftherelevant
result being inexplicable in terms of a given theory and thereby laying beyond our
control.Wehavearguedthat,firstofall,considerationsofthevalueofsurpriseinscience
shouldbe extended to thought experiments and theoreticalderivations and secondly,
thatitisusefultoseetheseasalsomorethan‘merely’surprisingandasdisruptive,ina
productivesensethatisbroaderthanconfoundment.32
Inallofthecasesconsideredherewecantiethesurpriseinvolvedtoacertain
disruptivefeature.InthecaseofbothGalileo’sthoughtexperimentandEinstein’stheory
of Special Relativity, the disruption was to pre-existing theoretical frameworks. It is
perhapsalmosttrivialtodescribetheE=mc2resultasdisruptive,giventhesubsequent
31Arefereehassuggestedthattakingsurpriseasamarkoffruitfulnessmightberelatedtocertainaccountsofcreativity(see,forexample,Livingston2009andThagardandStewart2011).TheremayalsobeaconnectiontowhatSheredosandBechtel(2020)call‘imaginativesuccess’,wherebyapossiblemechanismisimaginedthatcohereswiththeavailableevidenceandistakentobehypotheticallycapableofproducingarelevantexplanandumrelatingtosomephenomenon(itisthenanothersteptodeterminewhetherthatmechanismisactuallyresponsibleforthatphenomenon).Thereismoretosayhere,particularlywithregardtotheroleoftheimagination,butweshallleavethatforanotheroccasion. 32Notethatourargumentsheredonotrequireonetoadoptarealiststancetowardseithertheoriesorthoughtexperiments.Onemightbeananti-realistofwhateverkindandstillmaintainthatsurpriseingeneralisvaluableinscience,notleastasindicativeofacertainfruitfulness,aswehaveindicatedhere,wherethatisdisengagedfromanynotionofthetheoriesthataredevelopedasaresult‘latchingonto’theworld,inwhateverrealistsense.
history.Nevertheless,itisworthnotingthatitcanbeseenasmultiplyso,beginningwith
remarksastoits‘cosmicalimportance’(Aston1922),andcontinuingwiththegrowing
realisationoftheimplicationsofFrischandMeitner’suseofit.Justasscientistsvaluethe
disruptiveexperimentalresultsinvestigatedbyRitson,sotheyvaluethisaspectofboth
thoughtexperiments,suchasGalileo’sandtheoreticalderivations,suchasEinstein’s.
Ofcourse,thisisnottheonlyrespectinwhichsurprisemayhavevaluealthough
itmaybe themost pertinent in the theoretical context. And although it is difficult to
conceiveofphenomenainandof themselvesas ‘fertile’ inthisrespect,onecansurely
extend the notion beyond themost theoretical levels to those typically described as
‘phenomenological’.33
Our core claim, then, is that focussing on this disruptive aspect allows us to
articulate an account of ‘productive surprise’ that accommodates surprising thought
experimentsandtheoreticalderivations.Wesuggestthatthisoffersabroaderand,aswe
havesaid,moreusefulperspectivefromwhichtoviewsurpriseinscience.34
References
Arcangeli,M.(2018),‘TheHiddenLinksbetweenReal,ThoughtandNumericalExperiments’CroatianJournalofPhilosophy17,pp.3-21. Arthur,R.(199).‘OnThoughtExperimentsasaPrioriScience’,InternationalStudiesinthePhilosophyofScience13,pp.215-29.Ball,P.(2020),‘BehindtheScreensofAlphaFold’,ChemistryWorld9thDecember;https://www.chemistryworld.com/opinion/behind-the-screens-of-alphafold/4012867.article
33Again,wearegratefultooneoftherefereesforurgingustobemoreexplicithere.34Thisisnottosaythat‘matterdoesn’tmatter’ofcourse!Thematerialityofphenomenaissignificant,invariousrespects,butjustnotinthewayMorgantakesit,whenitcomestosurprise,withheremphasisonthewaythematerialworldcanconfound.WerecallBoyd’spointthatwhatmattersisthatscientificevidenceshouldderivefromacausalchainthatisanchoredintheworld-whatwearesuggestinghere,ineffect,isthatsurpriseconceivedofasdisruptivecanariseatanypointalongthischain,andbeyond.
Bedessem,B. andRuphy,S. (2019). ‘Scientific autonomyand theunpredictabilityofscientific inquiry: The unexpectedmight not bewhere youwould expect ’, Studies inHistoryandPhilosophyofScience73,pp.1-7.Beisbart,C.(2018).“AreComputerSimulationsExperiments?AndIfNot,HowAreThey
RelatedtoEachOther?”EuropeanJournalforPhilosophyofScience8,no.2Beisbart, C. (2012). “How Can Computer Simulations Produce New Knowledge?”
EuropeanJournalforPhilosophyofScience2Beisbart,C.andJ.Norton.(2012).“WhyMonteCarloSimulationsAreInferencesand
NotExperiments.”InternationalStudiesinthePhilosophyofScience26,no.4:403–22Bokulich,Alisa.2001.“RethinkingThoughtExperiments.”PerspectivesonScience9,no.
3:285–307.Boumans,M.(2012).“MathematicsasQuasi-MattertoBuildModelsasInstruments.”
InProbabilities, Laws, and Structures, edited by Dennis Dieks,Wenceslao J. Gonzalez,Stephan Hartmann,Michael Stöltzner, andMarcelWeber, 307–18. The Philosophy ofScienceinaEuropeanPerspective3.SpringerNetherlandsBorn,M.(1969).PhysicsinMyGeneration;Springer-Verlag.
Boyd,N.(2018),‚EvidenceEnriched‘,PhilosophyofScience,85,pp.403–421.Brendel,E. (2018). ‘AreThoughtExperimentsMerePicturesqueArguments?’ InThe
RoutledgeCompaniontoThoughtExperimentsBrown, J. R. (1986). “Thought Experiments since the Scientific Revolution.”
InternationalStudiesinthePhilosophyofScience1,no.1:1–15.Currie,A.(2018).“TheArgumentfromSurprise.”CanadianJournalofPhilosophy48,no.
5:639–61.DaCosta,N.andS.French.(2003).ScienceandPartialTruth:AUnitaryApproachto
ModelsandScientificReasoning,OxfordUniversityPress.Egeland,J.(2019).‘ImaginationCannotJustifyEmpiricalBelief’,Episteme,1-7.https://doi.org/10.1017/epi.2019.22.
Dardashti,R., Thébault,K. and Winsberg, E. (2017), ‘Confirmation via AnalogueSimulation:WhatDumbHolesCouldTellUsaboutGravity’TheBritish Journal for thePhilosophyofScience68,pp.55–89.
DiPaolo,E.A.,J.NobleandS.Bullock(2000)“SimulationModelsasOpaqueThought
Experiments.” InSeventh International Conference onArtificial Life, edited byMarkA.
Bedau,JohnS.McCaskill,NormanPackard,andSteenRasmussen,497–506.MITPress,Cambridge,MADutilh Novaes, C. (2019) “The Beauty (?) Of Mathematical Proofs.” In Advances in
Experimental Philosophy of Logic and Mathematics, edited by Andrew Aberdein andMatthewInglis,63–93.London:BloomsburyAcademicEinstein, A. (1905). ‘Does the Inertia of a Body Depend on its Energy-Content?’
www.fourmilab.ch/etexts/einstein/E_mc2/e_mc2.pdf
Einstein,A.(1909),‘EntwicklungunsererAnschauungenüberdasWesenunddieKonstitutionderStrahlung,’PhysikalischeZeitschrift,10:817-825.Feyerabend,P.(1975),AgainstMethod.NewLeftBooks.French, S. (1995). “The Esperable Uberty of QuantumChromodynamics.” Studies in
History and Philosophy of Science Part B: Studies in History and Philosophy ofModernPhysics26,no.1:87–105French, S., and P. Vickers. (2011). “Are There No Such Things as Theories.”British
JournalforthePhilosophyofScience62French,S.(2020).ThereAreNoSuchThingsAsTheories.OxfordUniversityPressGendler, T. S. (1998). “Galileo and the Indispensability of Scientific Thought
Experiment.”TheBritishJournalforthePhilosophyofScience49,no.3:397–424.Hacking.I.(1983),RepresentingandIntervening.CambridgeUniversityPress.Hitchcock,C.andSober,E.(2004),“PredictionversesAccommodationandtheRiskof
Overfitting”,BritishJournalforthePhilosophyofScience55:1-34.
Horwich,P.(1982),ProbabilityandEvidence,Cambridge:CambridgeUniversityPress.Huron, D.B. (2006). Sweet Anticipation: Music and the Psychology of Expectation.
Cambridge:MITPress.Judge,J.(2018).‘Thesurprisingthingaboutmusicalsurprise’,Analysis78:225-234.
Kind,A.(2018),‘HowImaginationGivesRisetoKnowledge’,inPerceptualImaginationandPerceptualMemory,editedbyFionaMacphersonandFabianDorsch.OxfordUniversityPress.Lenhard,J.(2018).“ThoughtExperimentsandSimulationExperiments.Exploring
HypotheticalWorlds.”InTheRoutledgeCompaniontoThoughtExperiments
Lenhard,J.(2019),CalculatedSurprises:APhilosophyofComputerSimulation.OxfordUniversityPress.
Livingston,P.(2009),‘ChapterSeven.Poincaré's'DelicateSieve':OnCreativityAndConstraintsInTheArts’,inTheIdeaofCreativity,editedbyK.Bardsley,D.DuttonandM.Krausz.Brill,pp.127-46.Mach,E.(1896).‘berGedankenexperimente’TranslatedbyW.O.Price,S.Krimsky:On
ThoughtExperiments,PhilosophicalForum4(3),446–457(1973).Meitner,L.(1964),“LookingBack”,BulletinofAtomicScientists20,pp.2-7,p.4. Mermin, N. D. (2011). Understanding Einstein’s 1905 derivation ofE=mc2.Studiesin
HistoryandPhilosophyofModernPhysics,42,1–2.
Morgan,M.S. (2005). “ExperimentsVersusModels:NewPhenomena, InferenceandSurprise.”JournalofEconomicMethodology12,no.2:317–329.Nolan, D. (1999). “Is fertility virtuous in its own right?”The British Journal for the
PhilosophyofScience50,265–282Norton,J.D.(1991).“ThoughtExperimentsinEinstein’sWork.”InThoughtExperiments
InScienceandPhilosophy,editedbyTamaraHorowitzandGeraldJ.Massey.Savage,MD:Rowman&LittlefieldNorton,JohnD.“AreThoughtExperimentsJustWhatYouThought?”CanadianJournal
ofPhilosophy26,no.3(1996):333–66.NortonS.,F.Suppe.(2001)Whyatmosphericmodelingisgoodscience.In:MillerC.,
Edwards P.N. (eds) Changing the atmosphere: Expert knowledge and environmentalgovernance.MITPress,Cambridge,pp67–105Ohanian,H.C.(2008).Einstein’sMistakes.NewYork:W.W.Norton&CoOhanian,H.C.(2009).‘DidEinsteinProveE=mc2?’,StudiesinHistoryandPhilosophyof
ModernPhysics40,167–173Ohanian, H.C. (2012). ‘A comment on Mermin’s ‘‘Understanding Einstein’s 1905
derivationofE=mc2”’StudiesinHistoryandPhilosophyofModernPhysics43,215–217Parke,E.C.(2014).“Experiments,Simulations,andEpistemicPrivilege.”Philosophyof
Science81,no.4:516–536.Parker,W.S.(2009).“DoesMatterReallyMatter?ComputerSimulations,Experiments,
andMateriality.”Synthese169,no.3:483–96.Peierls,R.(1979),SurprisesinTheoreticalPhysics,PrincetonUniversityPress.
Peirce, C.S. (1913), An Essay toward Improving Our Reasoning in Security and inUberty|EP2:472;seehttp://www.commens.org/dictionary/term/ubertyPoincaré, H. (1906). ‘The End of Matter’ (La Fin de la Matière, first published
inAthenæum(1906),reprintedin"LaScienceetl'hypothèse"(editionfrom1917),Chap.14.)PatriciaRife,P.(2019),LisaMeitnerandtheDawnoftheNuclearAge,PlunkettLake
Press2019Ritson, S. 2020. “Probing Novelty at the LHC: Heuristic Appraisal of Disruptive
Experimentation.”StudiesinHistoryandPhilosophyofSciencePartB:StudiesinHistoryandPhilosophyofModernPhysics69.Schindler, S. (2017), “Theoretical fertilityMcMullin-style” European Journal for the
PhilosophyofScience7:151–173.
Sheredos,B.,andBechtel,W.(2020),‘ImaginingMechanismswithDiagrams,’inTheScientificImagination:PhilosophicalandPsychologicalPerspectives,editedbyArnonLevyandPeterGodfrey-Smith.OxfordUniversityPress. Sime,R.L.(1997),LiseMeitneralifeinphysicsAmericanCouncilofLearnedSocieties.Sorensen,Roy.(1992)ThoughtExperiments,NewYork:OxfordUniversityPress.Stock,K.(2007).‘Sartre,WittgensteinandLearningfromImagination’,inP.Goldieand
E.Schellekens(eds),PhilosophyandConceptualArt,OxfordUniversityPresspp.171-194.Stuart,MichaelT.(2016)“NortonandtheLogicofThoughtExperiments”.Axiomathes
26,no.4:451–466Stuart, Michael T. (2020). “The Productive Anarchy of Scientific Imagination.”
PhilosophyofScience87no.5Stuart,MichaelT.andNancyNersessian(2019)“PeekingInsidetheBlackBox:ANew
KindofScientifcVisualization”,MindsandMachines29:87–107
Thagard,P.,andStewart,T.(2011),‘TheAha!Experience:CreativityThroughEmergentBindinginNeuralNetworks’,CognitiveScience35:1-33.Todd,Cain.(2020).“Imagination,AestheticFeelings,andScientificReasoning.”TheAestheticsofScience;Beauty,ImaginationandUnderstanding,editedbyMilenaIvanovaandStevenFrench,RoutledgeVickers,P.(2013).UnderstandingInconsistentScience.OUPWhite,A.(1990).TheLanguageofImagination,B.Blackwell.