1 CA•pm Six )

Reflections on My Critics

"Rtjlutio,u 011 M,y Critia'' U a ltngr!.y rep!y 10 seven t.Jsays- 6y jolm /P(Jl ·

kiív, Supl.~, Toulmin, L. P~aJU /Pi/Hams, Karl Popptr, 111nrg(Jrtt Mo.s .. urmatt, lmn Laktllos, anJ Poul F~uaknd-tat'h mort ()f ltss mii('Q/ o/ iJuu pul [MI•atá by Kuhn, uptcially in Tite Structure or Scientific Rovolu­liOns. TJu. jnt fou.r of dtrne usays "'u~ pn.s~nuJ. follnwi"g cut introJutrory pap<r lty Kuhn, nilcd "Logit of Disromy or Psycltology of IV'<ar<A!" .u a s;ymptuium mtitltd ''Crúitisrn ,.,¡ tlu e,...,;, of Knowlcdgt" ut tite FaunJ. lnttmunO..u/ G.l/"fuium in rltt Pltl'->plty af Sa'<n«, lrt/J In Lo,J., in JulJ tg&S. T~c fifila USCJY "'41 tompltu.J Q ytt~r laru, /Ju1 t!tt la~t twO. anJ /(ulut i rtp/y. H'trt NH compltttJ umi/ 1!}®. Afia[ tlu.Jc • ·m tlttn puMúAtd tOXttlur ._. Criticism :and ohe Growth of Knowledge. eJiuJ lty lmrt Lo~utt» onJ Atan Mwpa>c (LonJM: C~riJgc UniYtnity Puu, (9JO). RcprinuJ .,;,;, riJt p4m1iuüm af Cam6riJge fJnivusisy Prus.

IT IS NO\\' POUR YllARS since Professor W;ukins and 1 cxchanged muoually im¡>enetrJble vicws ao the lntemational Culloquium in o he Phi­losophy of Science held ao lk'<iford College, London. Rercading our conrributions. cogtlhcr with those that have since accre1td ro 1hem. 1 am tt:mpled to posit the exiscence of rwo TI1omas Kuhns.. Kuhn 1 is the :1uthor o( 1his essay and of an earlier pie«- in 1his ,·olume.1 He a.lso

"l'houp .,. b.tdor wwh. ,. •• ..., • ~ ~-'C'd ... aJa.og - biiW iOr ... .,. ~ c. G. .. _. .,.. R. E- C....ty bocio .....,.1 ., mc1 •r fino ... _,.,. .,.. oKn u..Nl tu~ b m i~tftX'fl&. ~ a ")-hX- 1 * ... put(ul to thna. but dwy ihouJd fiOC k w..mn '" .. y "......,_ •· T. $. Kuhft. •Lop oiiAJCJI)"í'n}' cw PsyddosY cf RdOKhl• .,, Cri~ ..J tlt ~ .¡ 1(.,...1,4J*: Prw.Juv, •f tAt ¡,.~ C.Ut!lf"4'-. .;. tÁr P~ .¡ St.t!Wt, 1.-J-

... CIIAI~T&R .SIX

publish<d in •96• a book colled Tlu Srruaure of Sriontifo II<>'Oiuuw, the one whieh he and \ lus Mostemun ~ ab<ne. Kuhn, is ohe au­thor of anooher book with the same tille. h is the one here cio<d reptal­<dly by Sir Karl Popper os .,-dJliS by Profe$SOI'l Feyerabend, lakatos. Toulmin, and W•okon•. Th:u borh boob be:lr ohe <>me tille c:annoo be altogether ;~mdeno.U. for the ,;t"., t~ present <>ft•n overlap and are, in ony c:~St. c>pr,...,<d in the same words. But dl<!or cenorol ~onccrm :.re, 1 c-oncludc, usuM.Iy very different. As tqK)ntd by hi$ critics (hi1 original ha• unformnately becn unavailable ro me), Kuhn, ~ems on occasion ro make poinu that sub,·ert essential ""pecu of the position outlined by his m1mesake.

L1cking thc wi1 10 exoend tbis iomoducoory fanrosy, 1 will insrcad explain why 1 ha ve embarked upon il. Much in this volume cestiñes ro what 1 dC$Crihed above as the gestllt switeh tbat divides readers of Srrurrur. into owo groups. Together <>;ith that book, ohis eollection of es<>ys oherefore provides an extended example of wl\31 1 ha ve clsewhere eall<d partial or incomplete communicañon-me rallting-ohrough-each­other mal r<gularly charaeterizes dis<:ourse berw«n participan!$ in in­comm~surablt poinlS of \rlt•'·

Such communic3tion br<akdov.'!l is importan! and n«ds mueh srudy. Unlike Paul Feyerabend (at least as 1 and omers ore reoding him), 1 do not belie,·e th;u it is evu con! or beyond recourse. Wlu:rt' he t.dk.s of incommensurabilioy wut rourt, 1 have regularly spoken also of portia! c:ommunic:uion. :md l believe it can be improved upon to whatevcr exltnt circum.smnces may dem.and and patience: pcm1itt a point to be claboraoccl below. But nci~tcr do 1 belicvc, os Sir Karl does, thot tbc sensc irl which '"we are prisoners caught in thc framework of our theo­ries¡ our CXJX.'Ctntio n s; our pasr experiences; our language" is merely "Pickwicki;on." Nor do 1 suppose thao "we Cóln break ou1 o( our frame· work 31 any 1ime ... [in10] a beuer and roomier one ... [from which] we con a1 any moment breo& ou1 ... again."' lf 1ha1 po~sibilioy were rouoinely >v:oilable, there ought to be no very special diffieuhies abou1 stepping inlo someone else's fromev.'Ork in order 10 evaluao. it. My crities' auempcs co step into mine suggest, ho-.:•ever, 1h:n c:h.ang~ o( fromev.·ork, of theory, of language, or of paradigm pose dceper prob­lems ofbooh principie and pracrice than the pr<e<ding quor.nlons recog·

.....,. ... •• ... 1 o...Lwo ....... ~·~ (e-bridge c...bndgo u.m""Y ........ ,.,.~ PP.. l•lJ .

.a. K. R. Poppet'. "Nilrm•l Snmcoe ltJid 1"' D.Jngm.. in C"Mvlt -.1 llk C.,.... cA •f ICMwk.t. p., ..

Rf:fi.ECTIONS ON WY CRITICS "' nitt. Titese problems are no1 simply those of ordinary discourse, nor will they be resok<d by quite the same teehniques. lf they eould be, or i( changes of framework -v.rere normal, occurring :n witl and :at ;my moment, thty would 001 be comparable. in Sir Karl's phra,..,, ro "ohe eulmre cWh(esJ .. •hich (ha.·e] stimulat<d sorne of tite greatest imdlec­rual n:volurioou" (p. ¡¡). The very possibiliry of that comparison iJ ..ho1 makes them so \·ery importom.

One especi•lly imeresting aspect of mis volume is, ohen, •h•• it pro­vides • develop<d exomple of a minor culture da.sh, of the severe oom­munic:nion diffiCtthies wltich characterize such cl>Shes, and of doe lin­guislic: techniques deployed in the auernpt to end thern. lle:1d as an examplc, il eould be an objec1 for srudy and analysis, providing concreoe information conceming a rype of developmcnral episode abou1 wloich we know vtry liule. For $0me readers, 1 suspect, the recurrcm (ailure of mese es!lays 10 intcrsect on imellec.rual issues will providc dtis book's gre:uest intercst. lndeed, beca~ those fa.ilures illustr.ne a phenomenon at the hcan of my own point of ,·icw) r.he book h:as th:n inrcres:c (or me. 1 am, however, too much a parrlcipant, too dee:ply in\'Oivcd, 10 provide the onalysis ..hieh the br<akdown of communic:nion wurams. lnstead, lhough lrtm~in co1winced oh!t lheir ñrt is frequently mispl=d and thal i1 often obscures the dceper differenc<s beiW<en Sir Karl"s •iews ond m y own, 1 must here spe>k primarily to o he poiniS raised by my present c:ritics..

Those pointS, cxcepling for the moment the ones roi~d in ~liJS Ma .. renmut•s stimularing paper, fall intO three coherenr c:uegoric..~. e-.tc.h of which iltu.scr.ues what 1 have jusc called Lhe failurc of our discussion 10 intt:rsc.-ct on issucs. ·n,c firsr, for purposn of m y discu$sion~ i" the per­ceived diffcrence in our mcthods: logic versus history nnd social psy­chology; normmive ve~us descriptive. These, as 1 sholl shortly •ry 10 show, are odd eonlrilSts witl1 which to discriminare ~1mong the contribu­•ors 10 this volume. All of us, u.nlike ohc members of wha1 has unlil reecmly bcen t.hc ma.i.n movcmeru i.n philo.ophy of sel<!nce. do f1i•uorical research and rely boob on it •nd on obsen .. ñon of conoemporory scien­tists in developing our \iewpoiniS. In those viewpoiniS, furthermore, the d«eriprive and the normoú\'e cre inextrícably mix<d. Thougb we may difTer in our 01an<hrds and surcly differ abou1 some manen of subsranee, we are scaottly 10 be distinguish<d by Otor medtods. The tide of my earlicr paper, "logic of Oiscovery or Psychology of Ro­seorch?" woo no1 chosen to suggest ..hat Sir K>rl oug4t todo bu1 rad1er l"O dcscrib.: w~atlu JIH$. When Lak.ams writes, .. Btu Kuhn•s conceptual

CHAPTER SlX

frnmework .. . is socio-p$ychologica~ mine is nommive,"' I can only think that he is employing n •lcight of hond '" r<-<erv< the philosophical mande for lúmself. Surely Feyerabend is riglu in daíming that my work rcpeatedly mak<s nonnative cloims. EquaU;- •un:ly, though the point \Vill rcqujre more discu.~~-ion, Laknros''l posirion is sociaJ .. psychologic.al in irs rcpeatcd relia.nce on dl!cisions govemed not by logical ruk-s but by the mature s<-nsibility of Ule trainéd scknrist. Ifl differ from Lakotos (or Sir Karl, FeyerabMd, Toulmin, or Watltins), it is with respect to substance rother than meú10d.

As tO suhstance, our most apparent düTerence is about normal sci­ence, dte topic to which I shaU tum immédiately aftcr discussing mcthod. A disproporrionate pan of this volume is devoted to normal science, and it caUs forth sorne of the oddest rhewric; normal science does not ex.ist ancl is unimeresting. On this issue we do disagree, bur 001, ( think, either consequentiaiJy Or in Lhe ways my C:rhÍC:S suppose4 When l r.tkc it up, l sball dcal in part with ll1e real difficulties in retriev­ing normal scicnüfic tradjtiOil$ from history, but my tirst and more cen­tral poim will be 3 logical one. The existence of normal science is a corollary of thc existence of revolutions, a point irnp~cit in Sir Karl's pnp<r nnd I!Xplioit in Lnkoros's. lfir did nor exist (or ifir w.r~ nonossen­rial, d.ispensable for science), tben revolutions would be in jeopardy also. IJut. about the lotter, 1 and my critics (excepting Toulmin) agree. Rcvolutions through criticism demand normal sciencc no less t11an revolutions through crisis. lnevirablyl the term 'cro:;s..purposes' berter catches the namre of our discourse thnn 'disagreemem'.

Discussion of nomlal scíence raí ses the third set of issues abour whích criticism has here dustered: t11e namre of the change from o ne normal­scicntifrc trndition to :mother and of thc techniques by wlüch thc rt­sulring conflicts are resolved . My critics respond 10 my views on this subjoct with charges of irrorionality, relativism, and the defense of mob ntle. Thesc are all labels which 1 caregorically rejoct, even when they are used in m y defcnsc by Feyerohcnd. To say that, in matters of theory choice, che fo rce of logic and observaúon cannot in principie be compel~ ling is ncithcr to discard logic and obscrvation nor to suggest th:n there are- not good rcasons fo r favoring o ne tl-u..>ory ov~r anothe r. To say that tr.~.ined sciemists a re, in such mauel"$, the highest coun o f appt.al is neither to defend mob rule nor to suggest that scientists couJd have

;. l. l.:a..ka~ -Fab.ik.\.Uon aM l.lk M~oOOiogy ofScltncilk Rtw:-arch Pmgnntmo.. .. !11 Cf'iti· (tlM QIIJ t.4( G /fiVitÁ ,¡ /Vti,..·IIJg,. p. .,.

RErLECTJO:-IS ON MY CRITICS "7

decided lO accept any theory at all. In this arca, too, my critics and I differ, bw our poin1s of difference have yet m be seen fo r what they are.

These three set.s of iss-ues- method, nonnaJ science, and mob rule­are the ones which bulk largest in this volume and, for that reason, in my response. 13ut m y reply cannot close without going one step beyond them to cons.ider the problem of paradigms ro which Miss Mastcnnan's essay is devoted. 1 concur in her judgmenr that the term 'p:tradigm' points to the centro! philosophical aspect of my book but that its treat­ment there is badly confused. No aspect of my v;ewpoint has evolved more since the book was written, and ber paper has helped in that devel­opment. Though my present pos-ilion diffcrs from hers in many details, we approach 'he problem in the samc spirit induding a oommon convic .. rion of d1e relevance of the philosophy of language and of memphor.

I shall not here be able ro deal at all fully with the problems presented by rny initia.l treatment of paradigms, but rwo considerations necessicate m y wuching upon them. E ven hrief discussion shouJd pennit the isola­tion o f two qui1e different ways in which tl1e u! rm is deploy'.od in my book and tbus eliminare a cons1ellalion of confusions which has handí· capped me as well as my critics. The resulring clarilication will, in addi­tion, pemit me ro suggest whar I r;~ke to be rhe roor of m y siHgle mosr fundamt'fltal clifference from Sir Karl.

He and his followers share with more trndirional philosophers of science the assumpúon tha t the problem of Lheory choice can be resolved by techniques which are semantically neutral. The observational conse­quences of both Ü1eories are tirst s tated in a shared basic vocabulary (not necessariJy complete or permanent). Sorne comparative mea~ure of their truth/f;¡Jsity coum then provides dte bas-is for a choice berweer1 them. For Sir Karl and his school, no less rhan for Camap and Reichcn­bach, canons of rnrionality thus derive exclusive! y from those of logical and linguistic syntax. Paul Feyerabend provides dre e.•ception which proves that rule. Denying the existenct of a vocabula.ry adequatt ro neutral observation report.s, he 3t once concludcs ro rhe intrinsic ir·rmio .. naliry of tbeory choice.

That conclusion is surely Pickwicki3n. No process essenti:JI ro scien .. titic developmem can be labeled 'irracional' wírhout vast violence to the term. lt is tlterefore fortunare that lhe concJusion is unnecessary. One can den y, as Feyerabend and Ido, the existence of a n observmion lan· guage shared in its enrirery by two theori<s and still hope to preserve good re·asons for choosing berween them. To ach_ieve th:u goal, how­ever1 philosophers of science will need 10 foJlow o ther contemporary

... CHAP1'tR SIX

philo.opher,~ in •"<"•mining, ro a pr<viously unpr<ttdtntcd dtpth, the manner in " 'hích langu~ fits tht world. osking how tem" attaeh 10 na1ure, how 1hose auachments are leamtd. and how they are rransmiued from on< g<ntr.nion 10 anot:her by t:ht mtrnben of a languag< commu­niry. Bcause p>rad.gms, in on• oC t:ht rwo stparablc aen>d of che term, are fundamtnt>l ro m y o•m attempts ro answer qutstions of that son, tbey must aliiO lind a place in this essay.

MttAuJoloy: TAt Role of History anJ Socioloay

Doubts :tbout 1hc appropria1eness of my methods ro my conclusions un he nwny o{ thc essays in this volume. History and sochd psyd1ology ore not, my critics claim, a proper basis for philosophical condusions. Their reserv.,ions are no1, bowever, aU of a piecc. 1 shall tlotrefore coMider s.riatim tht somowhot difforent foml< tltey .U.e in the essays by Sir Korl, Watkins, Feytrab<nd, and Lakatos.

Sir K>rl condudes bis paper by pointing out that to him "the idoa of ruming for tnlightenmenr conc:rming the aims of scltnce, and ÍIS

possible progrtss, 10 sociology or psyehology (or ... 10 tbe history of sclenee) is surprising and disappointing .... bow," he asks, "can the .-.gress to thtse oft<n spurious sclenees hdp us in this panicular diffi­culty?"'' 1 o.m puuled to k.now what these runark.s intmd, for in thl$ o.rea 1 tloink there are no differeoce$ betwe<n Sir Karl and myself. Jf he me:1n5 rh;u the generaliz.ations which const:itule receivtd thMries in sociology ond psychology (and history~) are weak recds from which 10 wcavc n philosophy of seience, 1 couJd not agrte mor< heartily. My work rclics on thern no more than hjs, lft on tl1e Olhcr hQnd, he is cl•allomging the relovanee 10 philosophy of scíence of the $<>rts of obser­vatíons collected by historians and sociologiSil, [ wonder how his own work is 10 be understood. His wrirings are crowdcd with historical <x­arnples 3nd v.•idl gt'ner:.lizarions a.bour scienriñc beha\•ior, sorne of rhem dt.cussed in my oarlitr essay. Ho does write on historical themes, and ho cito those popers in his centr.tl pbilosopbieal .. ·orks. A consisten• intcrest in historical problems and a ..,;Uingttess to engage in original his10rieal r<Search distinguishts the men be lw trained from the mem­bers of ony othtr CU<ffnt scbool in pbilosophy of scltnc:e. On thtse pointS 1 am an unrepentant Popperian.

R.6FLBCTIOS$ O!'t MY CIUTICS "' John Wotkins voice$ a differeot son of doubt. Early in hís paper he

writts that "methodology ... is eoneemed ..,;lb scienee at its best, or with scl<nce as it should be conducted, rathcr than ..,;lb h•ck scltnee, ·• a point ..,;,h which, at least in a more carcful formularion, 1 fully agree. Lattr he argues that wbat 1 ~, .• called normal scltnc:e is hock sclenu, and he then aslts why 1 am so •eoocemed 10 up-v:olue Nonnol Seienco and down-value Extraordinary Science" (p. ¡t). In so fu as that ques­rion ¡, about normal science in particular, 1 reserve my re-sponse umil latcr (•• which point l •hallattempt also to unravcl Watkins's cxtraordi­nary distortion of my position). But Watkins seems aliiO 10 be nsking a more general qucnion, one thar relates closcly 10 an i.ssue raised by Feyerabend. 8oth grano, m least for tbe sake of oheir argumcnt, that scienlists do behave as 1 have said they do (1 shall later consider their qualilications of tha1 concession). Why should the philosopher or meth­odologist, thoy then ask, take the facrs seriously? He is, aftor all, con­cerned not with • full descriprion of scicnee but witb tl~e discovory of tht ~ndals of the eruerpñse, i.e., with r.ationaJ rccon.stmction. By what right and whot crittria does the hi .. orian/ observer or sociologist/ obs6ver tell the pbilosopher which Faas of sclentilic life he must include in his reconstruction, whícb he may igoore~

To avoid lengthy disquisitions on the philosophy of history and of sociology, 1 restrict myself 10 a peNOnal response. 1 om no less ron­cerned with n.tiona1 reconstrucóon. with the ditiCOvery o( n~tials., than are philosoph<N of sclence. M y objecrive, too, is •n under,~tanding Of S<:iente, O( 1he rt3.SOM (or its speciaJ effic;tcy, of tl1é cognicive &131U$ of itS thcorits. Out unlike most philosophers of scíencc, 1 beg•n as a historian o( seienoe, examiningdosely 1he fact.S of scien1Uic life. H:wing discovered in the proce .. that much scientific hehovior, including that of the vcry greottst scientistS, persistently violmtd accepted mcthod­ological eanons, 1 had 10 ask "'hy those failures ro oonfonn did not seen• at all to inhibit the succ<SS of tloe enterpri~. When l la ter díscovercd that an alt~red v1ew o( the n:lrurc of scicnc:c tnn~rormed what h:~d pt'f!vioutly seomed aherrant behovior into an <SS<ntial part of an explanotion for sclence's suecas, che discovery ,..,.. a source of ronlidence ín that new uplanotion. M y criterion for emphasizing any panicular ospect of scien­tilic behavior is thorefore not simply that it oeeurs, nor merely that it oceun frequently, but rather that it fits a theory of sclenñfic knowledge.

, .. J. W. N. W..ti• , •Apjmc 'Nomu! ~·.· i:n Cn'Ul:UM .-.u/ ,Ac C...tA .¡ X..JIJ~,

p. ~7·

OJ O CIIAPTBR S IX

Con,·ersely, my conlidence in rJw meory derives from its ability lO make cohtffllc =se of many facts which. on an oldtr -"ew, had been tich'" abemnc or irrel.,,.nt. Re.ders will ~·e a c:írcula.ricy in me argumenr, buc it iJ not \.-icions. and in presettet doa not at aU distin­guish my vicw from •"-of n>y preso<n~ criucs. Here, coo, 1 am b<ha\'· ing os chey do.

n ••• my criceria for discriminating betwcen che essential and nones­senciolelemencs of nbser<ed scientifu: bebovior ""' toa significanc extcnt chcorecicol provides al so an answer to whar f eyerabend calls dcc amhi­gcchy o( my prcsencacion. A"' Kuhn's remarks abouc sciencilic develop­ment1 he a~ks. to be read as descripúons or prescriptíons?' TI1c answcr, of eou....,, is ch:11 chcy should be read in bod1 way• ac once. 1( 1 bave a theory o( how and why sc:ience wotks, il muSt necessarily have impli· cations for che way in which scienrists shoold behavc if chcir encerprise is 10 flourish. TI1c Slrueture of my argumenc is simple and, J 1hink, uncaoepcionablc: scientisrs behave in the following ways; those modes o( behavior h•ve (he"' 1heory encers) che following essential funetions; in tht-~ of an altmu.te mode tÁIJJ •'()ulJ strYc .si'mihu JU11cricns, scitnrisu should behavt tsSenúally as they do if thcir concem is 10 improve scientihc kno..,ledg~.

Note thac nothing in that argument sets the v•lue o( science ilsel~ and that ftyerabend's "plea for hedonism• (p. 109) is correspondingly irrdtv:anc. Panly bcc-du.se they have misconstru«<: my prcscri.ption (a poinc 10 which 1 shall "''um), both Sir Karl and Feyerabtnd find men­nce in che encerprisc 1 ha ve described. h i.s "liable to corncpt our under­sconding and diminish our pleasure" (Feyerab<nd, p. 109); ic is "a dan­ger . , . indecd to our civili7.ation" (Sir Karl, p. 1)). 1 arn not led 10

th:u cvt1lua1 ion nor :an many of m y readers, but nothing in m y argu· mem depends on ÍIS bting wrong. To expi:Un why an emerprise works is no1 10 approve or disapprove it.

l.okacos's paper raises a founh problem about method, •nd il is che most fundamental of al l. 1 have aJready confessed m y inability to under­stand whac he means when he says things likt, • Kuhn 's conceprual frome,.'Ork ... is socio-psychological: mine is normotivc." lf 1 ask, however. not what be intcnds, but why he finds chis son o( rhe1oric oppropriatc, an imponanc poin1 emerges, on< that is almos1 explicit in

" P K. r., .. .t.n.~. "c....Lot""" ro. el>< Spcciomo.-., c,;,;,.,..,.¡.w c-.¡.¡x-JJp. p. lf$. r Of -' (a, cktptt W ll'IOft d.l'dÜI ~tion ofiOil'W CON<tlti 1n • hít"' fht d6tripri,,.e ..M notNtl\~ tflfrgt>. xc- S. ~vtll. •MU$1 Wc Mat~ W'b.l1 We Sayt• in A(,.,., W, M1.ut ll'l.t W, $d) 'l A 8()(llt •f EJH.JI (N~· Y0tk: Scrlhcler. 1969), pp. 1- .. J.

RBFLitCTIONS ON Nl' CA.ITICS '" the firs1 porogroph of his section 4· Sorne of che pñnciples deployed in my explanation o( scienoc ...., irreduc:íbly soc:íological, at least at this •imt. In ponioular. confromed ,.; ,h the problem of 1htory choioe, thc srronurt o ( my ""Jll"SC runs roughly as follo""' takc a group o( thc ablest ., .. ilablc people wich the mosr appropriate motivacion; train chem in some scíence and in t~ speciahies ~re-... -ant •o the choice :u hoand; imbue them .,,¡,h the value system, lhe ideology1 current in chtir di$ci. pline (and 10 o grtot cJ<ttnt in 01her scienúfic fields os well); and, finolly, /ti tlttm ma,X_t tlfe ··/,m'c.t . [f t_hal technique dot:S OOT :ICC.'OUOC for scientific <levtlopment as we know it, Uu.':n no other will. T here c:~.n be no ser of rules of choice adequatc 10 dicr.uc desircd 1iuJividiJGI beh~wior in 1he

concrete casc::J lluu sdcntists will mee1 in the course of their c:~recrs .

\Vh:uever scientilic J)rogress muy be, we must account for it by examin­ing the na tu re of 1he scitntific gt'Oup, di.scovering wh:u il vnlues, what ic roler.H~, and what it disdains.

Th:u position is inuinsie-.ill)• sociologíca1 and. as such, a m~jor rctre;tt from the canons of explana ñon lic<nsed by the cradicions ._,hich Lalunos l.abeb jusriñalionism illnd falsificarionism, bo•h dognuuic ~nd naivt. 1 5hllll lat<r ip«ify it funbcr iiMI d~frnd it. But my prtsent concem is simply wich Ít$ >trueturt, which both Labtos and Sir Karllind unaccept­able in principie. M y quemion i.s, why should chey? Boch rq><atedly use arguments o( the samt Struc-lur~ themsrelva .

Sir K:.rl doa not, il is l'rue, do so al1 the rime. Thac p;an of hi$ writing which seeks an algorithm for verisimilirude would, if •ucc<'SSful. eliminate all need for recourse 10 group valuts, to judgmenc> mode by minds prtpored in a partictdar way. But. as 1 pointed out ac the end o(

my previous cssny, tl~ert are many passagts throughout Sir Karl's wric­ings which can only be read a,s descriptions of thc v:lltteli. and auitude.s. which sciemiscs must posse~s if, whe:n the chips :are down, 1hcy are 10 succeed in i.idv:.nc-ing thcir enterprise. Lakatos's sophistieated (:.lsificaa úonism goes even funher. In all but a few rt'Sp<Cts, only '"'O o( thcm C"SSCn&il*l, hi• po~hion ¡j now \·ery do-seto my own. Amnng the rnpect<t in whkh wt agr~, though ht has nor yet seen it, is our common u.se o( explanatory principies 1hat ...., ullima•ely sociological or ideological in s.tructurc.

lakotos's sophiSticated falsificarioni.sm i.obccs • numbtr of i»ues about which KiCniÍSI$ empJoying the mcchod must mue deci<ions, indi­vidual! y or collcccively. (1 discrust thc tcrm 'decision' in this conctxt since ic implie1 conscious de:liberalion on ead• issue prior 10 1ht anump· rion of 1.1 rde::arch sr2nce. For the moment, however. 1 &hall use ir. UntiJ

CllAPTrm SI X

the lasr se<:tion o{ this paf"'r very línle will depend upon rhe distinction between making a d...;sion and finding onesclfin the posirion tbat would ha ve resuhed from mak.ing i~) Scientislll must, for eomple, dende which statements to make "unfalsifinble by fiDI" and which not.; Or, dealing with a probabilistic theory, they must decide on a probability threshold bdow which statistical .:vlden<>! will he held "uu:onsistl<llt'' with that theory (p. t"')). Above all, vil'Wing theories as research programs to be evaluaced over time, s.cicntisrs must de~..·;Je whether a given program at a given time is "progressive .. (whence stienúñc) or "'degeneraúve"' (whcnce pseudo-scientiJic) (p. n8 ff.). lf the first, it is w be pursued; if the lauer, rejected.

Notice now that a caiJ for decisions like these may be read in Ewo ways. h may be rakcn tO nan1e or describe decision points for which procedures ~tpplicable in concrete cases must srill be supplied. On this reading l...:tka10s has yec co cell us how sciemislS are to select che panicu· lar Statements that are to be unfalsiJiablc by their fia<; he musr also srill specify critcria which can be used at the time to distinguish a degenera­tivc from a prog•cssivc <esearch program; and so on. Orherwis<, he has tOid us nothing at all. Alrernarively, bis remarks about the need for particular decisions may be read a$ al.re:ady complere descriptlons (:u least in form- tlteir particular content may be prelitninary) of direc­Livcs, or maxims which the scientist is requircd 10 follow. On düs imer­pret<uion, the third decision direcdve would rcad: 04 As a scientist., you may nor refrain from deciding wherher your resean:h program is pro­gressive or degeneral'ive, and you must rake the consequences of your detision, abandoning the program in one case, pursuing it in the othcr:· Corrt'Spondingly, the second directive would read: "Working witb a probabilistic theory, you musr consrandy ask yourself,vhethcr the result of so me particular expcrimenr is not so improbable as co be inconsistcm wit-h your thoory, arld you must, as a scienti.*'t, also ans-wer." Finally, rhe ñrst directive would read: ''/\$a sc:ientisr, you wiJI ha ve ro take risks, choosing ccrtain st3temems as the basis for your work and ignoring, at least until your research program has develof"'d, all actual and potemial auacks upon them ...

Thc SC.."(Ond reading is, of course, far weaker rhan tite firsr. lt demands the same decisions, but it neither supplies nor promises ro supply rules which would dictate rl1eir outcomes. lnstead, ir assimilates these deci ..

RBFLECT IONS ON ~y CRlTtCS •))

sions to judgments of value (a subject about which J sha.ll have more to say) rathcr than t'O measuremcnrs or comput~tions, say, of weiglu. Nevertheless, conceived merely as imperarives which commit che scien­tlst to making cer1ain sortS of dec-isions, these direct:ives are snong enough to affect scientific developrnent profoundly. A group whosc mcmbers felt no obligarions to wresde with suc.h decisions (but which insread emphasiz.ed others, or none at all) would behave in notably dill'erent wnys, and dteir discipline would change accordingly. Though La.karos's discussion of his dccísion directives is often equivoca!, 1 believe that it is just this second sorc of efficacy upon which his meth .. odology d<f"'nds. Cerrainly he does litde to specify algorithms by which the dedsions he demands are to be made, and the 1enor of hi.s discuss-ion of naive and dogmatic falsificationism suggests t.h:u he no longer thinks sueh specificalion possible. Jn that C3Se, however. his deci· sion imperatives are, in fonn though not always in coment, idemicul to my own. TI1cy spccify idc.--ological cornmitments whicb sdentists must .share if their cntetprise is to succeed. They are therefore irreducibly sociological in cl-le same sense and 10 t.he same extent as m y explan.atory principies.

Under these circ:urnsrances 1 am oot sure wh.ar Lakatos is criticizing or what, in thl$ arca, he dtinks we disagree about. A str.mgc footnotc late in h.is paper may, however, providc 3 due:

11u~re are l'W() ki'rui.J t>fpsydwlugútt( philt>Jophiu ofs~il'.n~~- ACCQrding co one kind rherc can be no philosophy of science: only a psychology of individual scientists. According 10 the orhcr kind there is 3 psydwlogy of the ·sc.·i~n· tifie; «idta.l," or "normal~ mind: this tums phíloSóphy of scicn«: inro a psychology of this ideal mind . . • • Kuhn does nor seem to have notioed tbis disrinetion. (p. tSo, n.J)

lfl understand him correctly, Lakatos idemifies tiJe firstltind ol' psychol­ogisúc philosophy of science "'rith me, the second wiLh himself. But he is misunders1anding me. We are not nearly so f;u apan as his descriprion would suggest, and, where we do difl'er, bis literal position would dc­mand a renunciation of our common goal.

Parr of what Lakatos is rejecúng is explanations that demand rccourse to the facrors which individuare particular scicnrists ("thc psychology of the individual scicnrist" versus "the psychology of the . . . 'normal' mind'). But tb;u does not separate us. ~!y re<:Ourse has been exclusively

1 J• CIU.PTHR SIX

co social psychology (1 prefer 'sociology'), a f.eld quice diiTer<nc from individual psydoology r<iter.ned n úmes. Correspondingly, my unic for purposn of oxplan>cion is the normal (i.e., nonpothological) scienrific group, occounc ~ing taktn of the foct thac itS mem~rs diffor buc noc o( whac makcs >ny gi•·en individual unique. In addition, Lakacos would like 10 r<jeCI di0$C charaaeristics of cvcn norm:ol scicnúf.c minds which make ahem che minds of human beings. Appor<ndy he seos no other w:~y 10 re•ain Lhe methodology of an ideal scit'nce in explaining 1ht observed succcss of accu>l sciencc. Bua his way will noc do if he hopcs 10 lll<l>lain an encerprise pr•criced by people. Thcr< ar< no ideal minds, and thc "psychology of d1is ideal mind" is d1erefore unavailable as • basis for cxplanoaion. Nor is Lakacos's monner of incroducing the ideal ncc..-dcd to achicvc what he aims :&t. Shared ideals :dl'ec:1 bchavior without making doo:ro who hold doem ideal. The type of c¡uestion 1 ask hos thereforc becn: how will a paniculat constellation of beliefs, values, ond impcrJtivcs affect group behavior~ My explanarions lollow from che answtr. 1 :am not sure Lak3t'OS me3n:s anytbing tlst':, bur, ifhe docs no11 the"' is noching in tbis arca for us to disagrce aboua.

Having misconmued the sociologic:ol b3se of my posirion, Lakotos and my othcr critics inevilllbly f.úl 10 norc a $J>Cá•l fcooru"' which fol· lows from taking che normal group rather than the normol mind as unh. Gh·en • shared algorithm odequote, let us say, to individual choice ~rw~ compcting theories or to the identification of ~vtre anomaly, all mcrnbers of • scienrific group .. ~u re><h the sarne decision. Thoc would be che e>se even if the algorithm were probabiliscic, for all chose who uscd it would evaluate the evidence in the same way. 1l1e effects of a shared ideology, however. are less unifonn, for itsrnode of ~pplica­tion is of a diO'erenc son. Given a group all the mccnbers of which are eommittcd to choosing bctween altemar.ive thc..-ories und also 10 consid~ cri.ng suc:h va1ue~ as accur3cy, simplicity, scope, and so on while m:aking thcir choice, the concrete decisions of individual membcts i t\ individual coses will nevertheless vaty. Group ~havior wiU be affected dccisively by thc sbared commitmentS, buc individual choice will ~a function al.so 0 ( personolity, educoaion, and the prior potttm of professional r<SCarclo. (Thcse ,,.riables .,. the province of indi,.;du:ol psychology.) To many of my critics this variabi.liry seems a weakness of my position. When considtring che problems of crisis and of theoty choice 1 sholl want, l10we• er. tO orgue that it is insceod a strtngth. IJ a decision must be rtlllde under ci""'msr.1noes in wbicb eveo tite most deliberoto and considered judgmcnt ""Y be wrong, ic may ~ vita.lly imponant that different indi·

RS f'LECTIONS ON MY CI\ITICS l)j

vidu•ls decide in di!Terent ways. How tlse could che group os • whole hedge its ~tS~1

NormGI Stiflttt: /u Nt~tuu ond F:tnctiottl

As to methocls, thcn, tite ones 1 ornploy are noc significa.ntly different from those of my Poppeñan crirics. Applying t.hosc: methods, we, of courk, draw somewhat different conclusions. but even thty 3rt no•. so far ap•rt •• $ever•l of my crirics believe.ln pardcular, •11 of us exccp11ng Toulmin share che conviction that the central <.-pisodcs in scientjflc :1d .. vance- those which moke the game wordo playing and dtc play worth srudying- are revolutions. Watkins is constructing an opponent from his own scrow when he descri~ me as having "down-valued" scicmific revolmions, taken a "phiiOS<>phical dislike" 10 thern, or sug¡¡e.ted chal they "con hardly ~ c:olled science •• :oll."' Discovering tite puuling no cure of revolutions was what drew me 10 hi>tory and philosophy of scitnce in the first pl><e. Almos• everything 1 bave wriurn •in..: de•ls with them, a fo.ct which Watkins poims out and then ignores.

Ir, ho••evor, we agr<e about this much, we cannot altogether disogr<e about normal science, the 05peCI of m y work .,.Júch most disaurbs m y presen1 eritics. By 1heir n.;arure revolurjon.s a.nnot be the whole of sci~ ence: somtthing difforcnt must necessarily go on in ~twecn. Sir Karl setS up tite point odmirably. Underlining whac 1 have alwoy• recognized as one o( our principal artas of agreemem, he s1resses thttt ""scientists n«ts.sarily devdop their ideas within a dcfinilc thoorctical ftamtwork" .'0

For hirn1 a.s forme, furthermore, r<>volutions demand such Cromeworks1

since they always in vol ve the rejeccion and replacemcnt of a fromework or of liOme of its integral ports. Since tl•e science which 1 call normal is precisely ...,,...Jrdo within • framework, it con only be che opposite side of • coin the face of which is revolutiorl>. No wonder Sir Karl h.aJ bttn lodlmly aware of rhe distinction .. betwecn normal s.ciencc and ...volu1ions (p. p). lt follows from his premises.

L 1( ...,._ mociV»*t wtrC' 1101 .u mue. dw pme dfen cauW b. .:fl.nft b) ,,.. ; 1Ci1Jc . .........,. .......... -~ ................................. -.... -cheoritt.. lht n;tQ ÍnctJO!ft to drpcnd OA the ~ o/ dw pn')baWnbe 4 cioe• ~ du.l altmur.:~in f~W.:d My poiftt by ttduc:Do ~ ablwdwn. ,_ Wad1at. "'Apimt 'NO!nDil ~·,"' pp. ¡a~ 1l.. anct.a,_ 10. Pclppn. ·NomW ~.· p. s•. iDID .lcf.ed. Unlc:w apliddy noclf'Cl. ,¡t i&aM- P"'~ ¡., cht q'IIOW.ont .n W• PliP"' arr in die: oñ¡Wk

.,. ClUP1'ER SIX

Something el>e follows os wdl. lf &aroeworlu are neccssary 10 ..:ien­IUIS, if 10 break with one i• i.nevi<ably 10 break into another- points which Sir Kllrl embrace$ up!icitl)•-then the hold of a framework on a >Cicn1is1's mind m• y not be occowutd for mml,y as the muh of his having """"" hadl) r>ught, ... a \'Íaim of mdoctrin•tion" (p. 1)). Nor may i1, as W •tlnns supposcs, be uplouned uuut(~· by referenee 10 the pr<valence of thlrd·r3tt mutd._ fit only for "plodding. uncritical" work." Thost things do ed>t, :md mos1 of them do damag<. Nevertheless, if frameworlu are 1he prcrequisitt of rese;~rch, their grip on tite mind is nor merc.ly "Pu.:kw1ckian/' nor can it be quite right to uy th:n, "if we try, we e:tn break om of our fra.mework at any ti.me."11 To be simulra­nt.'Ously cs.scniÍ:II a11d freely dispensible is very ne¡¡rly :a contr;adiclion i.n terms. M y critics become incoherent wben they embrace it.

Non e uf tha1 is said in an effon to show tlmt m y cri1ics really agree .. .;,h me, if only they knew i1. They do not! Rather I a.m trying, by eliminating irrelevoncies, 10 discover what we disagre< abou1. l hove so far argutd tha1 Sir Karl's phrase 'revolu<ions in permanente' does 001, any more 1hon 'square circle', describe a phcnomcnon thot could exist. F' r3m<WOrks mus1 be Uvtd witb and uplored before they c:an be brokcn. But 1h~1 does not imply tMI ~túts ouglu no1 oí m 01 pe~tu:ol framework-breaking, bowever unobru.uble that goal. 'Revolurions in permanenc:e' rould name an imponan1 ideología.! im~r3tive. lfSir Kllrl and 1 di~>"f~ :u a.ll abou1 normal science, i1 is over this point. He and bis groop •r¡,'ll< 1hat 1he scientist should ery at all times 10 be 3 eri1k ond 3 prolifcr>tor of al1emate theories. 1 urge the desirabili1y of an :them;ue str3tegy which reserves such ~h3vior for spccial occasions.

Tit:u disagrecmenr, being res:triote-d to rescarch scrategy, is alrcady n3rrower Lhan 1he onc my cri1ics have envis.agcd. To sce what is ;u stoke i1 rnust be n>rrowtd furtlter. Everything th3t has been said so far, though phrased for ..:ience and scientists, applies equally to a number of other fi<• lcls. My methodological pmcrip1ion is, howevcr, direc1td exdusively 10 the sciences and, among them, 10 those 6elds whieh dis­play the special developmenal panem known as progress. Sir Korl neody utche< the diStinction 1 have in mind. Al the st>rt of his p3per he 'O'TÍtes: • 'A >Cienrist cngaged in a pieee of r<S<arch ... c:~n go a1 onee 10 the h ... n of .. . an organiztd structure ... (and of) a gcnerally ocxep1td probltm·siruarion ... peaving) i1 10 01hers to 61 his rontribu·

u. w,.-.-. "'Apn• 'Normal Scwnet','"' p. ) .t.

u. Popf~ft. ·~otn\AI ~ ... p. J6.

RIFLiiCTI ONS OS MY CJI\ITICS .,, tion into the framework of >Cien<ific knowltdge.' ... the philosopher," he rontinues, "finds himstlfin a differcn1 position."11 Neverthelm, Mv­ing pointed 10 the ditTermce, Sir Karl there:Úte.r ignores h, recomme-nd· ing the same stra1egy to both scien<ists and philosophers. In the piOClCSS he misses 1he ronsequenees for researcb design of the special detail and precision with whicl~ as he >ays, the &amowork of a morure >Cience infonns lis prxtitioners what to do. In the absenc:e of 1hsu det:.iled guidance, Sir Karl's critic:~l srrateg)' seems 10 me the very best available. h will no1 induce the special developmcntal pauen> which choracterizes, say, physics, bu1 neither will any otber mcthodologic>l pnlscription. Given a framework which does provide such guidanee, however, Lhen 1 do int.cnd my merhodological recommendat:ions to upply.

Consider for o moment rhe evolution of philosophy or of the arts since the end of the Renaissan<e. n,.,., are fields oftcn contraSttd wi1h c.he esrablished sciences as ones which do not progress. TI~3t contrast cannot be due to t.he absence of uvolutions or of 3n intervening mode­of normal pr.l(tice. On the contrary, long befare the similor strucrur< o( scien<ific developm<nl was norictd. histOrian$ ponraytd 1hese fields as devdoping through a succession of uadirions punctuo1td by revolu· tion1ry :olterations of artistic style ónd bsle Or of philosophical view· poin1 and goal. Nor can the ronttaSI be due 10 the absence from philoso­phy and the ans of • Popperian methodology. M Mi.<S Mosterman observes for philosophy," 1.hese are juSI 1he fields in which il is bes1 exemplifitd, in which praetitioners do find eurr<nl tradi1ion stiRing, do struggle 10 break with it, and do regular\ y seek a sryle ora philosophic:ol viewpoint of their own. In the arts, in particular, the work of men who do not s-uccttd in innovation is described as 'derivative', a term of dero­gation .signiflc;mtly absent from scientific discoursc, which docs. on the othcr bond, repeatedly refer 10 'fads'. In none of rhese flelds, wltether aru or philosoplty, does the practirioner who fails to alter troditional praetiee lmve signifie>nl impact on tbe discipline' S devclop01tn1.'1 Thcse

. ,. ~. "NomW Srim:t. .. ,.. , •. Rc*n- ... kno•· m,· s~ •1 ~;,Nrfo R.n«Móo­<~ u.,;nn~ty o(Chicog!> p-.... , ~;u~ bow<b<ly su K.d'• ,.. ... -....... id& b 110 ochm, 11) "' .. ~ w., che fnmon,.'Or\ ol tnrftbli,t \.M'> l.rdct .. c-.--. J:h,t ~ iep' AM o( ey dtiaipóot• o! nornuJ IÓtna'. ... 14.-..,... s ... -.of• l'>ndop.- .. c.;,;,;.._..., c-..~.¡~W-~<q.. ,.., 1t t). FOf • Wtt ~ c/4ilrmncts ~ ~- artttbC ~ and ~ rlk<»~c .... = t · ¡de\-cloprntnul plUft'M. tft'my •Gommomt• [on tbt R«Ü~Jo!h.ol~ md An), e-y...,;.., SI.Jiu • s.mty-' HiMt]' u ( a96t) : •oJ-U;. tcpñnK'd M -<"..ocNncm a. tht kdMiont o(~ •tMI Art,• ia 1lc F..uuvial T uu;...: Sdmt.l St.Wiu.,. W,.,.J< T,.Ji,_, ,., ~~ (G~ Uni\'fNI)' a{ Ch.i~ p~ '9'77). fP· ,..~, •.

' .. CliAPTER SIX

are, in short, ftelds lO which Sir K3rl's rncthod is cssemial because wilh­our constam criticism and the prollferation of new modes of pracc:ice lhere would be no revolutions. Substiluting my own melhodology for Sir KarJ•s wouJd induce sragnnrion for exactly the reasons my crirics undcrscore. In no obvious seuse, howevcr, docs hi.s met.hodology pro­duce progress. Tite relation of pre .. to po~"t-revoluúonary practice in these fields is nol what we have leamed ro expect from thc devdoped sciences.

My critics will sugges1 that dte reasons for that diRerence are obvi­ous. Fields like philosophy and tl1e arts do no1 claim 10 be sciences, nor do they satisfy Sir Karl's demarcatioo criterion. They do no~ that is, gcneralc resulrs which can in principie be lested through a poim-by­point comparison wirh nature. But that argument seems t.o me mistaken. Without satisfying Sir Karl's criterion dtese fields could not be sciences, but lhey could nevenheless progress as 1he sciences do. In antiquity and during the Renaissance, the ans r~nher U1an tbe sciences provided 1hc accep1ed paradigms of progress." Few philosophers 6nd reasons of principie why d1eir field should not move steadily ahead, though many bemoan its failure to do so. ln any case, there are many fields- I sltall ~u them proto-se:iences-in which pr3cti~e does generate te-stable con­clusioos bu1 whicb nonetheless rcsemble philosophy and the arrs rad1er than thc established sdences in their devclopmemal pauems. 1 r.hink, for example, of fields Üke chemisrry and electriciry b<fore lhe mid­cighteemh cenlury, of the srudy of heredity and phylogeny before the mid-nineleemh, or of many of the social sciences today. In these fields, wo, though they s.atisfy Sir Karl's demarcation criterion, incessam criti ... cism and continua) striving for a fresh sran are prima_ry forces, and need lO be. No more than in philosophy and the ans, however, do they resuh in dear-t:ut progre:ss.

1 conclude, in short, dtat the proto-sciences, like the arts and philoso­phy, lack sorne elemem which, in the mature sciences, permits the more obvious fonns of progress. h is not, howe,•er, anything that a method­ologkal prcscrip<ion can provide. Unlike my presen1 critics, Lakatos at Litis point included, 1 claim no therapy 10 assist the 1ransforma<ion of a proro-sciencc t<> a scienc:e, nor do 1 suppose th::u anydüng of the son is 10 be had. If, as Ftyerabend suggesrs, sorne social scien1ists lake ftOm me the view th01 lhey can improve lhe srnrus of tbeir field by first

16. E. H. (;Qmbñth, An oM /llw*· A StuJy ,·,. rM P¡;ytA.~t.r o/ PietorrG.' R.tprm11um·"" (N~.,.., Vqrlt: t>:mth~ 1'}6o). pp. u ti.

RBFI.ECTJONS ON MY CR IT ICS ' 19

legishuing agreemem on fundamentals and t.hen ruming to puzzJe-. soiving, they are badly misconsrruing m y point." A sentence 1 once used when discussing the special efficacy of marl1em:uical theories ap­plics equally hcrt: "As in individual developmem, so in the scientific group, ma!Urity comes most sureiy 10 1hose who know how to wait."" Fonunatdy, though no prescription will force ir, che trnnsition to matu­rity docs come 10 many fields, and it is well wonh waiting and strug­gli~tg to attain. E.o'lch of the curremly cst-ablishcd sciences has emerged from a previously more spcculative branch of natural philosophy) medi· cine, or the cnúts at some relatively well defined period in the past. Other fie lds will surdy cxpericnce thc samc transition in the future. Only after it occurs does progress becomc an obvious: charaetcristic of a field. And only then do those prescriptions of mine which my critics decry come inlo play.

About the n3ture of that change 1 ha ve wrinen at lengd1 in Structurt and more briefiy when discussing dematcation ctiteria in my earlier contribution [0 this volume. Here 1 shall be conrent with an abst-ract descriptive summary. Confine attention first 10 flelds which aim to ex­plain in dernil sorne rnnge of 1ta1ural phenomena. ( If, as m y critics poim out, my funber descripúon fits theology and bank robbery a.o; well, no problems are 1hereby creared.) Such a field first gains maturity wheo provided with lbeory and lechniquc which satisfy the four following conditions. First is Sir KarPs demarcation cri1erion, without which no field is pottn1ially a science: for sorne range of narural phenomena, con­c.rete predlctions mus t emerge from Úle practic.c of the field. Second, fo r sorne imeresring subdass of phenome1\a, wharever passes for predictive success must be consisremly achieved. (Ptolemaic astronomy always predicted planetary position within widcly recogni1..ed limit-S of e.rror. The companion ast.rological 1radidon could nol, except for rbe tides and d1e average menstrual cycle, specify in advance which predicrion would succeed, which fai l.) Third, predictive tec)uliques must havc roors in a rheory which, however mct-:.phy8ie-al, simult:tncously juscilie-.s them, explains thcir limi1ed success, and suggesrs means for their improvemem in both precision and scope. Finally, the improvement of predicrive r.echnique must be a cbaUenging rASk, demanding on occasions the very highcst measure of ralent and devotion.

' 7· F~)"C'~, .. Consob clot\J fot thr.Sp«WlM; p. 198. Nou:-. ho"'·~'f:"t, that the p~~ Feyu· a:bencf quotts in IIOit ) don 001 P)' at :di • •hJ.¡ he rq>Cim..

1! . 5t"f' T. S. Kuhn,~ FlmC:l"ion o( ~Sc-.ag,¡~t in Mocknt l'lty~bl Sd~'" bu 11 (196a).

P· 190·

... CltAPTSI\ SJX

11t<S<: conditions >re, of ~ tantamoum to ohe description of a good scientilic th'"''Y· Bw oooe bope for > th<r:~peutic prescription is abondoncd, there is no reasoo ro expec:t ln)~hong !<SS. My daim has bccn- it is my sm~le gmuine ~reemem with Sir Karl about normal science- that ,..;th such a rheory in h>nd the rime for lttady criticism •nd th.ory pmliftt;tnOI) has p~. Scientists for the fi~t time ha vean alttmativc which is not merely aping wbat has gone befo~. They can intttoad opply their talenl3 to the punln: which líe in wh:ac Uk:uos now eolls the "protective belt." One of their objectives then is to extend the rnnge nnd precision of existing experiment and theory os well as to improvc the mmch betwee.n them. Another is tO elinlin:ue conAicts both berwecn the differem ~oeories employed in ~1ei r work and between 1he woys in which • single theory is uscd in differem npplications. (Watkins is riglu, l now think, in charging tha1 my book gives too small a role 10 the<c ínter- and intra-tloeoretic puz.zles, bul ukatos's anempt lo reduce scienct to matltcmatics, lea,•ing no signifiant role 10 e:x:perimmt, goes vastly too far. He eould not, for example, be mo~ mistaken about the irrelevance of ti~ Balmer fonnula ro the developmtnt of Bohr's atom modcl.") Thcse puu.lcs and olhcrs IThelhem consúru1c thc main activil}' o( normal .cic:ntt. 1ñough 1 can.nOt :arguc the poi.nt apn, thcy ano not,

pa<t Wadtins, for hacks, nor do they, pau Sir Karl. ~le the prob­lems of applicd science and engineering. Of course 1he men f:ucina1cd by them ore a s~cial brecd, but so are ph.ilosophers or artis~S.

E ven givtn 3 theory which pennics norm:Jl scie:nct, however. scien­riStS necd not engage the puzzles it supplies. They eould in5teod beha,•e as prac1ítioncrs of the proto·sciences musl; they could, that is, seek potcntial wenk spots, of which there are a1w:ays large numbers~ and endeovor ro erect ahernate ú1eories around them. Most of my present crioics believe thC)' should do so. 1 disagree but exclusívely on strntegic grounds. Feyer.lbcnd mispre<cnos me in a way 1 panicularly rcgrct whcn he rcpor", for cxample, thot 1 "criricized Bohm for disrurbing lite uni­formity of the contemporary quanrum thi!Ory. •» M y record as a trouble­maker should be hard 10 reeoncile with rhat repon. In fact, 1 eonfcsscd

,,. ....,..,.o.. · f:·' S .,. • .,. ... l"lM~~dx-ro&eolnpm.w.. .. rou.crdwou(tñ­~ -.eh ol l..tb.ot't ,..u. For die: acoNI roit o( cbc- &aletr ~ 10 Bolw':~o W'Oft. trt J. L H<Aron * T. S. Xuha.. ~ Gmc:d:. of ct.. SoN Aun. .. H~ sw- M Jw P~utJ Sn,.,.l 1 (1"'}: :u..,o. JO. f c,·cuMN. ·~ IOr dw Spm.aliM.• p. :o6. An ¡mplki1 ;,¡n~~' 10 thc Wftl~ F~·roJxnd dr•'" ~ my miNCies ~'".U'd &hm :ttld EiMcri" • «itb wíU M t"ouod b.&,w

R8PLICTIO~S ON' MY CftiTIC$ '"

to Feyerabend that 1 shared Bohm's discomem butthought his exclusive auenúon ro it almost ce:rtain to fa.il. No one, 1 suggesred, wa.s likt.ly to resol ve the paradoxes of the quanrum theory unril he eould relate them to sorne concrete tecbnical puu.le of current physics. In the de"eloped sciences, unlil:c pbilosophy, it is rechnical puulesthat provide the usual OCC25ion :md oftcn the conettte m.aterials for ~voiUiion. Their availabil­iry 1ogether with 1he infonnarion and $ignals 1hey provide accoun1 in large pan for the speeial narure of scientific progress. BecnW<! they can ordinorily to.ke cur~nt theory for granted, exploiting rother titan crit­icbdng it, rhc prac-ri1ioner$ of marure :;clences ;¡re frccd 10 t:xplor<: n:uure lO on esotcric depdo and detail otl•erwise unimaginable. Uccause that exploration will ulrimau~ly isolate severe trouble spots, t.hey c:m be con­fident that the pursuit of normal science will infonn chern whi!J\ ami wht~ they can most usefully become Popperian crities. Evcn in the developcd sciences, !Itere is an essential role for Sir Korl's methO<Iology. h is thc str:uegy appropriate to 1hose occasions '\\•ht.n something goes wrong with nonnal scie!nce. when the discipline encounters crisis.

1 hl\-. discusscd those points •• gr<at ltngtlt elsewhere ond shall not daborate them bere. Let me ins<cad condudc this sectiOft by retwning to the generalwt.ion with which it began. Despite the energy and spoce which my aitics h~ve: cfevo1ed to it, 1 do 001 think the position just oudincd depans very greatly from Sir Kort's. On thís seo of qu~tíons our difTer<nces are over nuances. 1 bold that in the dcveloped sciences occa!lions for criticism need not, :md by most praaitioners ought not, deliberately tx. sought. When they are found, • decem re.¡t.raint is tht appropriate fi~t responso. Sir Karl, though he ,,,.,. the need to defend a theory wheJ\ first auacked, gi\•es more emphasis rhan 1 10 d1e pur· po'"'ful search for wcak points. There is not n great deal to choose bcrween us.

Wlty is it, then, thut my preStnt critics see our cmci31 difTerenc., he~? One rcason 1 ha ve already suggested: their sense- which 1 do nm sbart> but whic:h iJ in any caR irrele,•ant- th:u m y s1r.ucg1c pretcript.ioo violates • higher mora~ty. A seeond reason, which 1 shall discuss in lhe next ~ion, is their apparent inability to see in historial e:x:amples doe detailcd funcrion• of thc b~down of normal science in S<tting rhe s:rage ror revoluti~ Lakatos's case histories a~ in this ~ panicularly inttresting, for "" describes dearly '"" transition from ohe progressive 10 the degenerative phase of a rtoearch program (the transi­tion from norm•l science to crisis) and dten appears to deny the critica! importance of wh:u mults. \Vith a chird reason, however, r mu.st de2l

CUAP'I'ER SIX

at thís poinL. lt enlerges from a c-ridcism \'Oiced by Watkins, which, howtvcr, in the present comext serves a purpose he by no mean< intends.

"By contr.l>l ,..;,h thc rclativdy sbarp idea of testobility." Wotkins "'"'"'· "the notion o( (normal science's)'=sing ade.quatcly 10 ouppon • puule-solving trodirion' is t$$C11Dally vague."" With thc charg< o(

vogueness 1 o¡;rcc, but it is a mist.ikc lO suppose that it difftrenriatcs my position from Sir Karl's. Wbat is prccisc obout Sir Karl's position is, 3$ W:nkin:s t1ISO poinl$ out1 the idea o( testabilily in principie. On that n.uch 1 rcly 100, for no theory that was not in prinriple tesmble could function or ooase ro function adequately when applicd 10 seicntific pu1.zle-solving. 1 do, despite Watkins's strangc failure 10 see it, rokt Sir Korl's notion of the asymmetry of falsification and conñrmntion very seriously indccd. What is vogue, however, obout my poshion is thc actual criterio (if tll31 is what is called for) 10 be opplied when dcciding whcther a particulor failure in punle-solving is or is not 10 be attributed 10 fundomcntaltheory and thus to btcome an oc:casion for detp con« m. n ••• dccision is, howcvtr, idenric:al in kind with thc decision wh<ther or not thc rcsuh of • particular ICSl acru•lly falsifies a panicular theory, ami on th .. t subi«t Sir K3TI is ~)' a'l or.ague as l. To dri\·e a •'Cdg< berw«n us on this issue, Wailins transfcrs thc shorpncss o(

tcsrability-in·principl< 10 thc shady arca o( tcstobility·in·pr.lcti« ,..¡lh· out even hinting how tht rransfer is to be effecttd. h is not an unprcce­dcnted mistakt, and it rcgul:trly makcs Sir Karl'• mcthodology appcor more a logic, less an ideology, than it is.

Besides, revcning 10 o point made •• the end of thc la<t se<:tion, onc m"y lcgitimatdy ask whether what Watkins colls vagucness is o disadvamage. All scienrists must be taoght-it is n viutl clcmcnt in their ideology- •o be aJen forand re:;ponsible to lheory breakdown, whether it be dcscribed as severt anomaly or falsification. ln adclhion, they rnust ~ supplied widl exantples of what their theories a1n, with sufficiem corc ami skill, be expccted 10 do. Givcn only tbat much, thcy will, of course. o(ttn rrach difTtrtnt judgmmts in co.ncrttt" ca~, Ont man seoing a cause of crisis where anothcr sccs only evidcnc< of limittd talent for resurch. But thcy do rcach judgmcnts, and their lock o( una­nimity ""'Y thcn be whal .. , ... thcir proftssion. Most judgmtnts th:u a theory has ccastd ade.quatcly ro suppon a punl~""lving mdition provc 10 hc \\'10ng. lf everyone agrttd in suc.h judgments, no one would

REFLECTIONS ON WY CP.ITICS

be ltft to sbow how exisring theory could accoum for th< apporent anomaly, as it usually does. If, on the olher hand, no onc wtre ,..¡lfing to t.ike the rislt and th<n seek an oltemole lheory, thcr< would be none o( tht revolurionary tran•formarions on whid> scicntific devtlopmcnt dtpcnds. As Watkins says, "there mUSt hc a critica( ltv<l at which a tolerablt"'"" into •n inrolcrable amount of anomaly" (p. )O). Butthot lcvtl ouglu not be th< sorne for e,·tryone, nor nccd any indhidual spcc­ify bis own toltranc:e lcvel in advance. He nccd only hc e<!rnin th31 ht has one and awarc o( sorne sons of discrepancies which would drive him towatd h.

Normal Scitnrt: /u Rurinol from History

1 have so far argutd that, if therc are revolutions, then there must be norma) sdenct. Ont may, however, legitimately 3$k whel_hcr t'ither ex· im. Toulmin has done so, and my Poppcrian critics have dilliculúcs in ~rrie\'ing from history a significam normal science upon the existence of which that of revolutions dcpends. Toulmin's qucstions are of panic­ular valut, for a rcsponsc 10 thtrn v.ill re.quire me to confront sorne gcnuinc difficultics presenttd by Srruaure and 10 modify my original prcsentation oecordingly. Unfonunately, howevcr, thosc dillicuhics • ..., not th< oncs Toulmin S<CS. Before thcy can be isolated, the dust he has impontd n1u01 be swcpt owoy.

Though tl•ere have betn imporwn changes in my position during tl1e sev<n years sincc m y book was publislted, the retreat from u cone<:m wi1.h macro· e o a concentration cm micro-revolutions i.s not among them. Part of tl1at rctrtat Toulmin finds by contrasting a papcr read in 1961 with a book pu6/ished in 1961.11 The papcr wa•, however, both wriucn and publishtd after th< book, and its first foomote spccifics the relation­ship which Toulmin invens. Other e\·idence of r<treot Toulmin re· uieves from a eomp:arison of the book v.-ith the manu!k:rip• o( m y lll'$1 cssay in this volume.u Bur no one clse has, lO my knowltdgt, even noticcd the difftrtnces which ht underlincs. and thc book i~ in any cas< quito cxplicit about tbt ccntraliry of d>C con«m whidt Toulmin linds

u. S. E. T.,._ ·o... d.. Di"""'-~ !<om»! anol "-~'"*"'Y Sdmcr H<oW '«'arnt· • e,.,;,;- .J w e,..,¡.¡ K-k.J_~~. ,... , r. 'l· S.. olto S. E. Tool .... -n.. E•~ !><>dopm<nl <>( N-.1 S......; A-'­~·tNU, " (tf6?)l .~6-7f, np«ially p. .. ; ..... l. 11le p.lbtiuttOn (1/ t.hi\ biosnfid c:anNd 1n ad'VU!Ot ol dv M'Udto Ofl ... bkb it daims to ~ bbtd t.. si"'"' mt much li"Oublr.

••• CIIAPTIK SIX

only in my mo~ r«ent work. Among tbe revolutions discussed in the body of 1he book are, lor <lClmple, dÍ$«1-.ries li.ke those of X rays and of tht pla.ne1 UranU$. • Admitttdlyt tht p~ Sl21ts, "tbe e1nension [of 1he tenn 'r<\Oiuoon' to epimes lil<e 1hes<) Stnins customary usage. Ne>~dess, 1 shall conunue 10 opeak. even of dúeo'•" .. as revolution­ary, bcc:ause it Í$ jU$t tite possibility of rebting tbeir SUUOIUrt 10 Wt of, say, the Copemican revolution thal makes tl•• ex1ondtd conceprion seem to me so import1ln1. "" My con.,.,m, in short. has never been wi1h scicndfic: rtvolmions as "'something Lh:at tended co happtn in a given branch of science only once every rwo hundrtd years or so."" Rather it has been throughout what Toulmin no"' takes it 10 have become: a littlt-Siudk'<l IYI"' of conceptual chang< which oc.:urs fr<qutntly in sci· ence :md is fundamental co itS advanee.

To 1ha1 conccm Toulmin's geological analogy is entircly appro­pri.ne, but noc in the way he uses it. He emphasizes the :.sptct of llu~ unifonnitarian.-cawtrophist debate whieh deah with the possibility of attributing cotastrophes 10 natural causes. and be suggests 1ha1 once tba1 issue had been resolved • 'carasttophes' became oniform a.nd law­govemed jusi like any otber geologjcal and ¡Waeootological pheoom­ma~ (p . .. J. my ita1ics). Bu e his insertion o( 1he tenn •unifonn' is gnru~

itous. Besides th< issue of natural causes, the debate hada second central aspett: the question " 'htther catastropbes ~isted, whetber a major role in geologic:al .,·olution should b< attribiittd to pbcnomona like e>nh­quakes and volcanic ac1ion " 'hich aeted more suddenly and destructively than crosion and 5<'dimentary deposition. This pan of the debote the unifonnilarians lost. When it was over, geologistS recognized rwo sons of geologicol chnng~. no less distinct because both due 10 natural causes¡ one acted grndually ond unifnnnly, the othcr suddenly ond c:uamophi· c:tlly. E ven today we do no1 crea1 tidal woves as sp<cial case< of erosion.

Correspondingly, my cbim has been, no1 thot rcvolutiOM were in­scrumble unit evcnts, bur that in science as in geology there are two sons of chongt. One of thcm, nonnal science, is the generolly cumula­tive process by which the ac.:epted b<üefs of a scientific community are lkshed out. oniculattd, and extended. h is what scionrists are tr.ained 10 do, and the main tradition in Engli.sb...speiling philooophy of scionoe derives from the ex.amination o( tbe exemplary works in which tba1

J+ C/. St.rwnru. pp. 1 {, On p. ' tbt pollliDimy of' accDd~ tbe woa pciolo co mkro-~tiCioftt il ~ u • '"(uMUI'H'tUal 1hnk'" o( thr boot.. lt. Toulr.rul'l, "Dod cM Di'"nctMwt.. • p.. ,u.

JU:FLIC:.TION'S ON MY CI\ITIC$ •••

tr.úning is embodied. Unfonunattly, as ind.icaced ln my previous tSS3f, proponents of 1ha1 philosophical tradition generally choose 1heir eum­ples from changos of another son which are tben tailorcd 10 fi1. 11te result is a failure 10 rteog~~iu the prevalenco of changes in ""hich con­<eptual comminnents fundamentalto tht practioe of sorne sciontiñc spe­cúlry muJt b< jettisoned and replaced. Of course, as Toulmin S>)'$, the two sons o( ch.ange incerpenetra1e: re,•olutions are no mo~ total in scionce than in other aspects o( life, bu1 recogni•ing c:ontinuity through revolurions ha8 not led hiscorian.s or anyone el se to abandon the nolion. h v.r:as a wc:tkneH of Strueture that it rould only name, not o._n:alp.e, rhe phenomenon h repea1edly referred 10 as 'parrial communication'. llut pard:tl eommuníc:u,ion vtas never, as Toulmin would h;wc h, .. complete (mutual) incomprehcMion" (p. 43). h named a problem 10 b< worked on., not elcvacéd co inscnll'abiliry. Unless we can leam more ubout it (1 shall offer sorne hines in che ncxt section), we shall continue co mi,l;).kt tbe natur< of scienti6c progress and thus perhaps ofknowledge. Nothing in Toulmin's essay begins tO porsuade me that wc •hall sucoeed if we c;ontinue 10 tre;~t aH scienrific change as onc.

The fUndamonr.~l challmge of his paper, how.-·er, remains. Can..,. d.istinguish m•re articulotions >nd extensions o( sho:rtd belitf from c:hanges whicb invol\'e rKOnstruaion.? 1'be answer in extreme c:ues is obviously •y es. • Bohr's th<'Ory of tbt hydrogen spccuum wu ,.,·olu­tionary as Sommerfeld's th<'Ory of tbe hydrogen line strocturt W11s not; Copemican astronomical th<'Ory was revolutionary bu1 the caloric lhe­ory of adi:tbatic compression was not. TI1ese examples are, howtvtr, 100 extreme 10 b< fitlly informa1ive: ther< are 100 many differences b<· twccn tlte theories c:omras:u~d, and the revolutionary changes afTected too mnny pcop1c:. F'ortun:uely, however1 we are not rcstricccd 10 chem: Ampere's 1heory of che electric c-ircuit \\"::S revolurionary (::u lcast among French electrid3ns), be-cause it severed elect:ric-currem and elt.-ctrost:.tic: effeetS wbich had previously b<en concoptually unittd. Ohm's law was again nwolutioruary, and was resi:ned according.Jy, hca•u!loe it dem:a.uded a reinl<¡vation of concepiS previously applied separ.uely 10 curren! and charge.• On the other hand, 1hc ]oule-Lenz law relating th• hea1 gener­:ued in a wire to the resistance and cutttnt was a product of nonn:tl science, for bo1h the qu•litative efftctS and the conceptS ~uircd for

,¡4. 0. tbtw ~ wc T. N. Brown_ ·n.r Ekuric Curmwt in r....ty S~.,_GmNry fmocb Phywtl.• HUttwitw/ ~;,. ,¡., PJty1itaf ~u r (•9'69): 6•- •0); U. L ~ •RMMC~t to Ohm't Lawt A••"'- j..,..,J .¡ P.A)·Uo l' ( tpfd 1)6--17.

CHAPTER SrX

quanlificotion we"' in hand. Ag3io. at a l"'·el whicb is not 50 obvi· ously theomic:al, LJ,·oisíu's ctiscm-ery of oxygen (though P"rhops not Sch..,lo's and 'u rol) not Prieodey's) w;u """'""0031'), for it was insop­arable from • new theory of c:ombusrion and aculity. Thc diSCIOvcry of noon, howcver, was not, for hdium bod suppli<d botb tbc notion of an incn g:as and thc nccdcd column of th< !"'riodtc tablt.

On• may quesrion, howover, how f.ar and how univorsolly this prc>­=s of discrimin•lion cm be presscd. 1 am fCP"•tcdly askcd whether suclt .. .-nd .. such a de,~clopmem '9.'01.S •inomt;¡J or revolutionary," and 1 usually ha ve 10 answcr that 1 do not know. Nothing deP"nds upon my, or anyone clse's. being able tO respond in cvery conc:eivable c:ls.e. bu1 much dcp<?nds on thc discrimination's bcing applicabl• to a far larger numbcr <>f "'""' tl~an hove b<oen supplied 50 far. Port of thc difficulty in an.swering i.s that rhe dis.crimination of normal from revolutionary episodes dcmands closc historical study, and few pon:s of the history of sc:ience have rtQe:ived it. One mUSt know no1 simply che mame of ¡¡,., ch>nge, but the norure and structu"' of group rommitments before ond after it occumd. Often, to determine""""'· one mu" tlso know the manncr in whicb the change was ..,.eived wben finl proposed. (Tbm is no • ..,. in which 1 a.m more d<q>ly conscious of the necd ror odditiontl hi><orical ..,..,.ro~,, though 1 disscnt from th< conclusions Pe•rce Wil· liams drows from that necd and doubt that the r<Sults of investigorion will dr.~v.• Sir Korl ond me closcr.) My difficulty, however, hlS a d"'!"'r >sp<?ct. Titough mucb depends upon more resc>rch, the invesrigarions requirtd are nor simply of t.he sort indicared above. Funhermore, the strucwrc of 1he argument in Struaurt somewhat obscur~ Lhe narure of wlm is miuing. lf 1 were re<vriting the book now 1 would signíficantly dt;_mge Íl$ orgonization.

Tite gist of 1he problem is that to answcr tltc qucstion "normal or revolutíon:uy?" onc must firsr ask, .. for whom? .. Somedmes thr answer is ~asy: Copernkan asaronomy was a tt"volution for cveryont; oxygen was a rc:volucion for chemistS but not fortsay, mathemacial astronomers unless, like Lapl:>«, they wef<' inrerestcd in chemical and thermol sub­jeas 100. For thc laner group oxygen was simply another gos, ond its diJCOvery "-as mercly an in~e:nt to theit knowledge; nothing essen­úal to thcm •s .,.ronomtrs had to be changcd in the discovery's assimi· t.tion. h ¡, not, ho .. ·evu, usu;illy possibleto identi(y groups which share cognilive commi1mencs simply by naming a scienrific subject maner­astronomy. chemisrry, mathe.rnaric::s, or the like. That is, however, whac 1 hove ju<t done here and did earli.er in my book. Sorne scientific sub-

JH:.,LICTIONS ON MY CRJTJCS

j..:tS-for <nmple, the study of heat- have bclongcd to differem sci· t>ntifac communitiH :u diffennt rime5, somerimn to Mvtrnl 11 onc:e, without bcroming the special provine< of any. In additioo, though scien· tisiS are muc.h more ne:uly unanimous 1n their commilmt>nts than pnc­titiontrs of, say, philosophy ond the ans. thA,re •"' .ucb tbint;< os sdiOOI< in science, rommunitits whieh approach the same subj«t from vcry difl"t>ren1 point.s o( vin.1• Fttnch r-lectricians in tltt> firs.t d«.ades of Ute nineteenth cenrury ., •• .., membcrs of a school which indudcd olmost none of the Bñtish dectñcians of the day, and so on. lf 1 were writing m y book a~r•in now, 1 would thereforc bcgin by discussing the commu­nity strucwre of sciencc, and 1 would not rely exclusively on sharcd su.bjcct nmuer in doirtg so. Communiry scruccurc i~ n topic about whic:h wc h:we very linle inform;:ation at prescnt, but i1 htts reccmly bccome a major concem for sociologists, and histOria.ns are now inc:reasingly concemcd widt it as weiJ.!'?

The ~·"'h problems invoh-ed ...., by no meatU trivial. Historians of science who eng-•g• in them muSt ce~ 10 rcly cxclusively on the u:chniquc:s o( the intelleawl historian and use rhose of 1he soci.al .tnd cu.lru.ral histori>n as well. Even thouglt work has scorcely begun, the"' is every reason ro i!ll~ it to su~ecd, ponicubrly for 1M developod sciencu, rhosc which h.:t\'C severed their his1oria.l fOOl$ in 1he philo­sophicol or medico! communities. What one "'-ould then hove "·ou.ld be a rostt':r o( 1he diiTe~m specialisC$' groups throug:h whic.h sclence w.ts advaneed :n various periods of rime. The oanalyric uni1 wQuld be the proctitíoners of • given specialty, men bound togcthcr by common de­meni.S in rheir educa1ion 3nd t.~pprcnriceship, aware o( cach mher's work, ami choracu:ri;(ed by the rclative fullness of their profc5sional communi .. c:uion and the rclativc unanimüy of their professiOI'\011 judgmcm. In 1he m:mare sciencts rhe members of such communilies would orclinarily ~e tl1etnselves and be scen by others as tlte men exdusively responsible for a givcn subject manee anda given set of goals, induding rht training of thcir s:ucces~rs. Reu-areh would. ltowc:ver, di~IMC tllct exi"ence o(

ri,-.¡ schools as well. Typicol rommuniries, •• lcost on the contemporory sc.'ientific scr-nt'-, may consisr of a hundred members) .sometimn signi6· contly (e.,•tr. Jndividuols, panicubrly the oblest, may bclong lO ~·· eral such groups. <ithA,r simult:meously or in suCCCS$ÍOn, and tl~ey .,;u %¡.A .._.u IIIIOI'C" &u.íW ~ of W. no~~ • d tOIN' prdumnar) ~ •· ""......, •• ..,. ·s.-.~'""""""'"' P~ • ., n. s-.¡s.. .. ¡, n-u.~. C'd. F •• (UrbaN: U..rvtnicy oi 111ioot. Ptft:l. •r.•>· Pf'· ,. \9 ll; n-printc!CI MI n, Euumill Tl!IMIM, pp. :t.9¡-p,.

••• CHAPT&R SIX

chango or 01 leas< •djust tbeir thinking cap; as 1hey go from one 10 another.

Croups liko 1h...o should. 1 suggest, be rtgardrd u 1he units which produce ;cí<nrific knnwlrdge. They coulcl nOt, o( coun<>, function ,..¡,¡,. out individuab .. mcmbers. but the vuy idea o! scienufic knowlrdge 3S a prh.•atc pruclue1 prestnts the 5ilJDe iotrinsic prob!enu as tllc notion o( a private langua¡(e. • p>rnlld ro whicb 1 shaU rctum. Neither knowl­rdge nor langu"t~• rem.aios the S3me wben conceívrd as something an individuo! can po~s •nd develop .tone. !t is, therefore, wíth rcspec1 tO groups like dtt~ tha1 the quesrion "normal or revolution:~ry?" should be asked. Mony episodes will dtcn be revolutionary for no comrnunitíes, many o1hers for only " single small group, still o1hers for severa! com· muniri~ 10gc1hcr, a few for all of science. PoS«! in chal way, the ques­rion will, 1 belicve, have answers as precise a.~ my distinccion requires. One reason for thinking so 1 shall illusttate in a momen1 by applying tl1is approach 10 sorne of the concrete cases usrd by m y critics 10 raísc doubtS about tl•e existcnce and role of normal science. First, however, 1 must poin1 Out one :aspect o( my present position which, far more dearly than normal sacnce, ncpresents • deep divide benleen m y view­poim and Sir K:u1's.

The program just oudinrd makes evcn dearcr rhan it has been before the sociologic>l hose of m y position. More imporrant, ir highlighcs wha1 has perhops no1 been dtor before, the e."en' 10 which 1 rtgord scítmiñc knowlcdge .. intrinsic.Uy a product of. congeries or specialím' eom­munitits. Sir K:ul sct.-s •a gr~at danger in ... s~ialiucion," and the conrcx1 in wltklt he provides 1his evaluarion suggesrs tha1 tlre danger Í$ che same one he sces in normal science.!S Buc with respect w che fonner, :u least, che banle has clearly been Jost from the start. Not chat one miglu not wish for gnod reosons to oppose speciali>-'llion and even succeed in doing so, bu1 tlt>l lhe effon would necessarily be to oppose science as well. Wltenever Sir Karl rontrasts science wi1h philosophy, os he de>« >t the sto.n of his p>per, or physics wí1h sociology, psychol­ogy, and history, as he does at the end, he is conmuting an esot:eric, iso131rd. and largely sdf-comained discipline with one that still aims to communiace wid1 and pe-rSUade an audience larger th1n thrir own

profossion. (Science is 1101 the only octivity the praaitioners of .. ·hich ean be grouprd imo communitíes, but it is the only ont in whkh each

REPLI!.CTIONS OS ).IY C IUTI C$ ... community is its own txclus:ive audien«- a.nd judge..'') The conuut is not 11 new one, chanc:teristic, say. ofBig Science and the QOntt:mporuy S«ne. Mathematics and astronomy were esoterie subjects in antiquity; mechanics became so after Colileo and Newton; elec:tticity af1er Cou­lomb and Poísson; and so on until economics today. For 1he nvost pon 1hat transition to a dosed 5pecialisos' group was pan o( 1he tr>nsition 10 marurity that 1 discussrd above when considtring the emergencc of puule-solving. lt is hord 10 believe that it is a dispct>sable chnr>ct<ristic. Perhaps science could ogain becomelike philosophy, liS Sir Karl wishcs, but 1 suspect thot be would then admire i1 less.

To conclude thís pan of my díscussion, 1 tum ro some concrete cases by means o( which m y criLics illustrate their diffiouhic-s in finding norm~l science ond its functions in hisrory, t.aklng up fi~t a problem r:tised by Sir Karl and Watldns. 8oth point ou1 that nolhing like a ronscnsus over (undamentals .. emerged du_ring the long bistory or fhe eheory o( matttr:

herc from the pre-Socratics to the presenr day rhere has been an unend­ing Jt-bate berween continuous and discontinuous concepts of mauer, berween various aromk theories on che one hand, and ethtr, w;ave and ficld theories on the other.•• Feyerobend makes a very similar point for the second ~j( of rhe nineteenth cenrury by con1rasting rhe mechanic:al, phenomenologial. and ñdd-theorerie approaches <O problems of pbys­ics.• Wi1h all of their descriptíons of what went on 1 agree. But tbe term 'cheories of mauer' does noc, a:t least until che l:ast thirty ye.;ars, even differenriale the coneerns of Kienee from those of philosophy, mueh less single out • eommuniry or smoll gmup of communitíes re­sponsible for ancl expen ín thc subject.

1 :lm no1 sugge:sting chat sdcntists do not have a1~d u.¡c theorit.os of mauer, nor that tlleir work is urtaffected by such theodes, nor that cheir rcsearch results have no role in the theories of mouer held by mhers. Bur untíl this century tl1eories of mancr have been 3 tool for scientists r>drer th•n a subject maner. Tbat cüfferen1 speciahics have ehoscn dif­ferent coolt :and sometirnes criticiud each o1flel"$' d10ic:es does nor mNn that 1hey ha ve no1 each been practicing nonnal science. The frcquenrly

,_S.. •r ·c........· ¡ ... doe ~ ofSricno< ..,.¡ An~ JO- wm-. ·Ap• ·somw~~·.· PP.,.. ft.,. s---11 .. & Warl:aft1; 11101n., o...ar,. ~"' ¡, ...,¡. • ....W ...... "'""...,.,... ol S...O... (P~-.1 Rnw.. 1l l• ... t 1l1-.o).,. e~ ,._ wid! ft rok o( ......,_ in chemisuy in dw lirw lulf ol dw fiiiM'Ift'ft• CC'MIN'Y• 1 &al 1rith dwt c-. ·~ t.Jow. l'· F.,.,...,, -~(o, oht Sp«bb;,..- p. -,.

.,. CIIAPTER SIX

heard gener:.Hz~tion thac, before the advent of wave mtchanics., physi·· cim and chemim deployed characreristic and irr<'d>ncilable thoories of moucr is 10<1 simplisric (panly because it can equ.Uy well be sald obout differem chemical speciahies e,·en today). But the very possibility of such a generaliunion suggesrs the way in whicb the issue raised by Watkins and Sir Karl musr be approacbed. For that mottcr, the prac­ririone.s of a given communiry or scbool need not always shore a thoory of mancr. ChemiStry during tbe first b.U of tbc ninct«'nth ccntury is a case in point. ·n10ugh many of irs fundamental rools- eonstant pro~ pon-iont muhiple proportion, eombining weiglus, and so on- had bcen dcveloped ;ond beeome common propcrty t1lrough O:~lton's atomic the­ory, thc mcn who used them could, after the event, odopt widely vory­lng :uti10dcs about the narurc and even tl1c ex:istcnec: of urom.s. Titeir discipline, or at ko:~st many parts of it, did not dcpcnd upon a shared model for m;nter.

Even where they admit thc existence of nonnal sdenco, my critics regularly have difficuhy di..overing crisis and its role. Watkins pro­vides an example, and its resoluúon foUo"''S at once from th~ son of analysi• deployed above. Keplu"s laws, Watll.ins renúnds us, wer< in­comp>tiblt with twton's pl-rary theory. but utronomen bad not previously been diss;¡risfied with them. Newton's re,·oluúonory treat­mtnt o( planttary motions was not, Wot.kins therefore usens, preceded by astronomical crisis. But why should it have been? In the first place, the tnnsilion from Keplerian to NeWionian orbits nc«< not have bem (ll:1.ck 1he cvidence 10 be cenain) a revolution for astronomers. Most of them followed Kcpler and explained the shape of the plonetary orbits in meclmnical rather than geometricaltenns. (Their explonotion did not, that is, makc use of the elllpse's 'geometric perfection', if nny, or of som'-' othcr ch:antcttristic of which the orbit was cJcprived by Newmniatt perturb>Lions.) 11tough tlte transiúon from circle to elllpse had becn pan of n rtvohuion for them1 a minor adjustment of mcchani.sm would accoum, as it did with Newton, for depanure from elllpticity. More imponant, NewtOn's odjustment of Keplerian orbits was a by-produa of his work in mechanic:s, a field to whicb tbt communiry of mothematical astronomerS made passing referenoe in tbeir prefaces but wbich tlttre•f­ter played ooly tbt most global role in thcir work. In mechanics, ltow­ever. where Nev.1on did induce a revolucion, thecc had been • ...;dely rtrogniud critis sin« the aoceptance of Copemic:anism. W:ukin.s's counttrcxample is tite beS< son of grist for my mili.

l tum finally to one of Laka10s's extended case hiStories, dUJt of the

R.itPLECTIONS ON MV CR.ITICS . ,. Bohr rese>rch program, for it illustratcs wh>t moSt pu:ai<S me about his often admirable paper and suggests bow deep evtn residuo! Popper­ianism can be. 1ñough his rerminology is dill'erem, his onalytic opparo­tus is as close 10 mine as need be: hard rore, work in the protecrive belt, and degentrative phase are cl<>S<! parallels for my paradignu, nor­mal science:, ~nd crisis. Y e:1 in impol"'tlnt ways l..akatos (-ails tO see ho'V.' these shared notions funerion even "'hen appi)'Íng them 10 " 'hat is for me an ideal case. let me illustrate sorne of tl1e thin~ he eould have seen and might hove said. My version, like his or like ony other bit of historical namnive~ will bt! a r.uional reconstruction. But 1 sh:111 no1 ask my readcrs 10 upply ·rons of sah' nor add foomotes poinling out 1l 1a t

wh:u is s.aid in my cext is falsc.u Considcr Lakatos's occounr of the origin of the Bohr otom. "The

background problem," he writcs, "was the riddle of how l\utl1erford atoms ... can rem:~ín ~able; for, aocording to the wcll-corrobor.ued Maxwell-Lortntz theory of electtomagnetism tl1cy sltould collopse. " 11

Thot is a genuino Popperian problem (not a Kuhnian pu:ule) orising from the conAicr berween rv.•o increasingly well establl<lted pans of physics. h bad, in addirion, been available for sorne time as a potenrial f<IW point for eririei$m. h did nor originare with Rutherford's modl'l in 1911; radiad•·• insrability was equ.Uy a dilliculry for most older atom models, induding both Thomson's and Nagaoka's. Furthermorc, it is the problem which Bohr (in sorne sense) soh•ed in his f•mous rhree­pan pape.r of 191}, thereby inauguraring a re,·olution. No "''onder La. katos would like it 10 be tite "background probletn" for the ,....arch program thot produced the revolution, but it cmphorically is not."

lnsu~ad, t1u: bnckground wu an entirdy nonnal puu lc. Bohr M:t our to improve the physical approximations in • paper by C. G. Darwin

p .. Labtot. '"flhif.ealioft.." pp. tJI, 140 . ... 6. atld ebc'Whe1t>. OM m•y fC'IIJOnlhJ)' at.k abo.11 tbc tvidcntUI (oru o( a:&mpkot ~~ all IOr thi., j(jft o( qu;..!iliatlon (tl'ld ;, '~ÜJCidon' quhe dw ri&IU wmdJ). I•IJ. ho~'er, in ll.Mihd CONteXt be vny IV.-uo(ul for 1hut ·~..,. h~ o( Lü.uoe' ~ More dnrly. bcat.uc mo« o:plkidy. &han 111y othcuu.mpln t tftOW, t:.lky lttlls­cnt< dx d'""-"' """"" dx "'1 phlloocph<n .,._.¡ bmonaM ...wlydo "'->'· Tlw ,..U... U. noc eN. ~ ·~ 1\\ely eo nuh n-ron-~ lni)w, tbt ÚCb bacrr ttwi!Nfty ..,._ who ...... - .. - ..¡,¡..u...., ..,._do ..... '1I"'P- ....... a... ~ ...,.W '* ittt-W ir .U. -mw a C..CU rqKIIn ..-.. ht W... MI M úlw. 1( M Ncl 6cww too M ..W be t0 WMiaw- to ~ offarte that ht couW aot ~ .. ..wy ~ •lootaot.t ~-IO .. BodoP""P'""~bacdxyddinm.Uclwy.,....,.. ..... -._ 1 h:noc dDallllrd 110aw ~ ol daD.1iiOrt ia ""1'&c-R~ ~ IINtlr)' ..nd ..,........,. oiSdmc.; ¡, 11< EunuiJ T..,;,.. W· ,_.._ JJ· Uk»m.. •fat.iM•Mft. .. p. , ,.,, H· For wbat (....._ lf'r lln~ *'MI :Kuhn. ""1'bt ~ o( tM Bobr At(Mft. ..

op CUAP1'BR SIX

on rhe energy lost by cha~ged parricles ¡>3S'ing rhrough mart<r. In the pro<:ess he made •·har "'35 to him rhe surprising discovery that rhe Rutherford atom. unlilte otber current models, was mechanically UJ\Sta­ble and that a Planck-like ad boc dC>'Ía! for stabilwn~ it provided a promising cxpl.mauon of lhe periodicities in ~tendelcev's table. some­rhing else for wbich he had nor boen looking. Ar thor poinr bis model 5till had no excited m res. oor was Bohr yet concomed 10 apply it 10 aromic spectra. 11woe steps followed. however, as he auempred 10 rec­oncile bis modcl with tite apparendy incompatible one developed by J. W. Nicholson and, in the process, encounrered Balmer's formula. Likc mucb or rhc r<-.e:trch that produces revolutions, Oohr's biggest achievemcnt.:J in '9'3 wcre products., therefore, of :a resea_rch progroam directed 10 gools very differenr from rhose obtained. Though he could nor bave stabilizcd the Rud1erford modeJ by quantization if unaware o( tl1e crisis whicb Planck's work had inrroduced ro physies, bis own work illunnues ,.,;,b particular clarity the revolutionary efficacy of nor­mal researeh puu.les.

&.>mine, 6nally, tite concluding porrion of Lahtos's case history, the dtgtnerative phase of the old quantwn tbeory. Most of tbe $10<y he ¡e)l.J ~11, 2nd 1 sl•all simply poim it up. From '900 on h waJ inc:u.u-­ingly widely recogniud among physicisrs thot Pla~k's quancum had introduced a fundamental inconsisteney inro physics. Ar ñnt mony o(

them tricd 10 elimina te it, but, after 191 t and p3rticularly after the inven­tion of Bohr's omm, thost cricic.al dfons were increasingly aba_ndoned. Einstein was, for more than a decade, the only physici! t o( note who contillucd to dircct hi~ energies toward r.he search for a consistem phys­ies. Otbers leamcd 10 live wit~ inconsisteney and tried instead 10 solve technical puzdes with the tools at hand. Particularly in the arcas o (

atomic spectr:t, :uomic structure, and specific heats, their nchievcments were unprce<demed. l11ough 1he inconsisteney of physical thcory was widely acknowledged, physicisrs could nevertheless exploit it and by doing so made fundamental discoveries atan extraordinary rote betwecn 1913 and 1911. Quite suddenly, howcver, beginning in 1911, tbese very SU~ 1\'tre se<n lO have oobted tbree obdurate prob)ems- the be­Jium modtl, tht anomalous ~ dl'ect, and oprieal dispenion­which could not. physicislS were increasingly convinced, bo resolved by anything quite like existing rechnique. As a resuh, many of them changed their researcl1 Slance, proliferaring more and wilder versions of rhe old quontum thcory tha.n bofore, designing and testing each auempt ag-•inst the tluee recognized ttOuble spots.

RBPLilCTJONS ON NY CRJTICS '11

h is this last phase, 1911 and aft<r. which Lakatcn call• 1hc degcncro­rive srage of Bohr's program. Forme it is • casebook example of crisis, dearly documented in publications, correspondence, ond anecdote. We ""' it in \'try nearly tbe same way. Labtos might tberefore havt told tht rest of the story. To those who 1\'ere experiencing this crisis, rwo o( the three problems wbich had provoked it proved immensely infor­m3tiv~, dispersion and the anomalou.s Zeeman effecc. By ;a series o( connecttd su~ps too complex co be outlined here, their pursuit led ti~t 10 the adoption in Copenhagen of an atom model in whiclt .o-colled vinual o:K:illamrs couplcd discrete quamum states-. rhen ro a formula IOr quanrum·theoreúc:al disJ>ersion, and finally m rmnrix mcdmnic:s whiclt terminrued thc crisi~ bardy r-hr(!(: years after it had begun. For llmt first formulmion oi qunntum mechanics, d1e degenerative phasc oi tht old quamum theory provided both occasion and muclt del3iled tt-chnical subst3n«. liiSiory of 5cicncc, to my knowlcdge, offc.rs no t..-<¡ually dl·ar, detailed, :tnd <X>gem example of the creari\'e functions o( normal scie.n~ and crisis.

Lak.atos, howeve:r, ignor6 thls chaprer and jump;, ins1cad 10 w¡ve mechanies, tht second and at ñnt quite different formulotion o( a new quancum theory. l'int, 1.., describes the degenerativo phose o( the old qwnrum theory u filled with •t"\•er more' st~rile incon.sistencies :md ever more oJ 4<>< bypotheses" ("oJ 4oe" and "inoonsistencies" are riglu; "sterile" could not be more wrong; not only did the:se hypoth..., lead 10 matrix mecbanic:s bm also 10 electron spin). Then, he produces 1he crisis·resolving innov:uion like a magjcian pulling a ,...bbh from a h:u: ~A rival rese:uch programme $00n appeart.od: wave rncch:mics ... [which] soon caught up with, vanquishcd and rcpl<>cc..t llohr's pro­gnamme. De Broglic's paper came at a time when Bohr's pi'(Jgrlmme w~s degenenuing. But ,¡,u was me.re C()ÍMidenec. One wondtl'$ wh:u would bave happcned if de Broglie had publisb,-d his poper in 1914 instead of 1914."~

T o the dosing rhctorica.l question, 1h~ answrr it cle;at: nothing at all. 8oth de Broglie's popcr and the route from it to the Schriidinger wave equation dcpend in detail on developments which oa:unrtd after 1914: on work by Einstein and by SchrOdinger bimsdf as well as on 1~ di.SC:O'\•cry o( tl1~ Compton dTect in 19~1..,. E ven if th:ac poim eould

n· t..a,t.,... '"f'abilotiOl'l.. • P· •s...: iufics adckd. '' SM M. J. Klm . ·~ atld dw \l'aw-Parddt Dluht)','"' 1M N~ PI.~) (•964l: . ... _.,;V. V, lla~~UA and P. Form.&tl!. *\\'hy Was lt Sc&róding.« Who ()rcl.f'lopcd de: Bt~~ú

ldn:J• H~--1 St..Ñu M dt PJ.p;.../ SÑN:u e (t96?) : ~9 • , ,..,.

CIIAPTER SIX

noo be documcnocd in dco;úl. ho .. ~. is not coancodcnce sornincd be­yond ....:ognioion .,.,.,., lL..d 10 exphin tJ,., simul12noou• emergence of two independcno and ao ñnt quite dilfm:no theoric.. both ca~le of r<SOiving a crisis oh>< had been visible for only three years!

Le< me be ...:rupulous. Thougl¡ Lakatos cnoirely missa tite esstntial creaoive functions o( ol1c crisis of tite old qu.mrum theory, he is noo a.hogether wrong abuuo it.'$ rde\'allOC w thc invcnoion of wave mtchan­ies. Tilc w:.ve equation \\'"3! nor a response to the crisis which began in 1911, bUI 10 the one which dates f!'()m PJanck's work in 1900 :md on which mos1 phy•icistS hild tumcd their backs after '9"· lf Eins1ein hod no1 tcnaciously refused to set aside his deep dissatisfoction with the fundamental inoonsistcncies of thc old quantum theory (and if he had not Jx.-en ~hlc ro auach lhnt discomem ro the concrete technical puv.les of ek-ctromogneoic flucouacion phenomeno- something for which he found no equivulent after •9•l), d.e wave equation would not have emerged when ond os it did .. The research rouoe whieh leads to it is not the same as the route 10 mat:rix mKhaniC$.

Buo neither are the rwo independent. nor is tbe simultaneity of their termiruuion due merely to colncidcnoc. Among the .ever.al research epi­~es which 1ie 1hem together is, for eumple. Compcon's convincing demonstr.nion in 19 11 of the particulote propenies of light. the by­produC'l of a vcry high-class piece of normal research on X-r.ay scaner­ing. lkfore physicistS could consider the idea of maner waves, dtey had firso 10 take the idea of olte pbooon seriously, and this few of ohcm had done bcforc 1911. De Uroglie's work started as phocon tl1cory, its main 1hrus1 bcing 10 re<:oncile Plonck's rodiation law with thc par1iculate structure of' liglnt m;ncer waves entered along t.he way. De Broglie him .. sclf m:1y no1 hnve needed Compton's di.scovery in ordcr co 1o.kc the phooon S<:riously, but his oudienee, Freneh and foreign, eet1ainly did. TI1ough wavc mcchanics in no sense follows from the Compton effec1, therc are t1i~1orie.a1 cíes beJW«n the cwo. On the road to matrix mechan· ics the role of the Comp1on effeet is even dearer. The first ~Be of ohe ,.¡nual oscillator model in Copenhagen wos to show how th:u elrect could be explaincd wiútout recourse to Einstein's photon, a concept tbat Bohr had been notoriously rducrant to accepo. 1ñe same model was next applied 10 dispersion ond the clues 10 mat:riJC mtchanico found. The Compton dTect iJ therefore one bridge a.cross the g;ap which Labros hide-s und~r "'roincidence."

Having providcd elsewhere many other examples of the significant roles of normal scienee and crisis, 1 sl1aU not multiply u1cm furtlter he re.

II.EFLECT ION$ OS MY CRI'fH:S

For bck of additional researeh 1 could noo, in ony c;¡sc, provide enough. When complcocd, thot researeh necd not beor me out, but wl13t has been done so f>r surely fails oo suppon my crirics. They must look funher for counte~mples.

1 considcr now onc lost set of eoneems voiccd by my pr<...:no critics, in t.his C3.SC one chey share with a numher of ocher phHosophers. h ariscs m3inly from m y descripdon of the procedures by which sciencisr.s choosc becwcen compcting theorles, and it resuhs in charges which dus· ter abom su('h ttrms as 'irr::nionality', 'mob rule', and 'rclacivism'. In this secrion 1 aim to climinate misu.ndersumdings fot which my own past rhetoñc is doubtless partially res¡xmsible.ln m y concluding section, which follows, 1 shall oouch upon sorne d<-eper issucs r>ised by the problem of theory dooioe. Ao ohot point the terms 'p•radigm' ond 'in­comm~urolbilicY • which 1 h:l\'e so far almost c-ncin:ly :wotdedt wiU ne«SS>rily reenter the discussion.

In StTWJurt, nonn:~l science is at one point d<$Cribed as "a Sttenuous and devotcd >ttempt to foroc noture into the coneepouol boxcs supplicd by professionol eduation" (p. l)· !.>ter, discussing thc problems which surround the choice bet"'ecn compering sets ofhoxcs, thoories, or p.1ra­digms, 1 described 1hem os:

ahou1 lt't'hni<(UCS o( pcrsua'lion, or abou1 arg\lmcm and coun1cr :1rgumem in a situ:ttion in • •hich ... neilhcr proo( nor error is at issuc. The trnnsfcr o( alh.-giance from p3radigm to pandigm is a conversion cxperitnee th:u c.:annot be (on:t<l. Lifclong rcsistance .. . is not :a viohuiun of ~it'mific: st:1.1ldards bu1 an index tOche n;nure of sciemific rese-arcll itscl( . ... Though thC' hi!ltOti.tn Q i\ al .. ll)'$ find mc:n-Prit.-sal~y. (or instancc:- who weru un .. rra~r\ablt to rffi.st (ora~ long as they did, he will not fin<l a poinll.U which l"t.$l~tancc becomn dlos;k:d or unscieutific:. At tnosc he may wbh 1.0 Q)'

lhat 1he man who continues to rt:S.ist ;afttr his wbole pro(mion hu b«n com;C'ntd has i¡uo .focto cea:sed to be a $Cientist. (p. t S t)

Nllt surprisingly (though 1 hove myself been '"•'Y much surprised), passoges lile oh<se are in some quaners read as implying thao, in the devdopcd sciences, miglu makes right. Members of a scicntific oommu­nity ean, 1 am held to have claimed, believe anytlting they please if only they will tirso decide whao oltey agr«o abou1 and olten enforce ir