Discussion 237
intéresse to u t particulièrem ent les professeurs d 'h isto ire ides sciences, et s u rto u t les a u te u rs d e traités.
En fait, il m e sem ble q u ’au cu n des systèm es de périodisation qui o n t été em ployés jusq u ’a u présent n ’est p leinem ent satisfaisan t et que l ’u tilisateu r doit choiisiir la solution la m oins m auvaise, oom pte-tenu d u b u t q u ’il se propose. Les coupures à in tro d u ire sont d e deu x types, l ’u n intern e, lié au développem ent m êm e d e la science, l’a u tre externe, lié à deis facteu rs extérieurs, agissant s u r île progrès scientifique. U ne découverte, u n e innovation m éthodologique, u n e sy n th èse originale peu v en t correspondre à u n e coupure du 'prem ier type.
Mais il me fa u t 'pas oublier que la d a te id’une découverte ou d ’une création e st difficile à fixer e t q u ’il fa u t distinguer en tre sa préparation, son éclosion, sa publication, sa diffusion e t soin adoption définitive. La découverte des rayons X, ren seig n em en t de la géom étrie descriptiv e p a r Moinge, les expériences de L aue s u r la d iffraction des ray on s X p a r les cristaux m a rq u e n t des 'Coupures im portantes et relativ em en t b ien p ré cisées; p ar contre d'introduction de lia g rav itatio n universelle, d e la théorie des groupes, de la théorie des. ensembles, de la génétique, des quanta, etc. sont des coupures très im portantes, m ais qui s’étalen t su r u ne longue période.
La R évolution française, su r le p la n m ondial, p a r les1 changem ents, q u ’elle a in tro d u its dans. les idomaimes d e l’enseignem ent et de la re cherche scientifique, la R évolution ru sse s u r le p la n national, so n t des exem ples d e coupures extern es aussi bien précisées. (Par contre, si le concept de Renaissance est u tile et commode, les ilimites chronologiques de cette période so n t difficiles' à fixer.
E n conclusion, je pense que la périodisation en 'histoire des sciences doit u tiliser ces deux types de critères, m ais en in sistan t s u r le fait que les coupures introduites, son t en p a rtie artificielles, q u ’elles s ’étendent so u vent su r une assez longue période e t varien t su iv an t les b ranches de sciences considérées. Les coupures adoptées pour l’ensem ble des sciences, comme celles que j’ai in trod u ites d ans m on Histoire générale des sciences, n e dbivent donc ê tre considérées que comme des points de rep ère moyens, dont la commodité et l ’utilité n e d o ivent p as cacher l’im précision et le caractère très relatif.
J. R. Ravetz
We can a ll ag ree th a t periodiizaition m ust not be a dogma, b u t ra th e r a guide to action. How is it to be used? F irst w e h av e th e deep philoso phical problem of describing complex q u alitativ e changes. I th in k we
238 La périodisation de l’histoire de la science et de la technique
do not hav e th e conceptual tools to do th is properly, a n d from, this follow m any of our difficulties. It seems to m e also th a t th e re is a dif ference betw een m a n y of u s and ou r M arxist colleagues. We a re surely concerned w ith th e sam e basic problem : understanding th e complex causes responsible for th e progress of science. B ut we seem to pursue this in (different ways.
As Professor Taton says: “Je suis plus em piriste”, I do not tr y to id entify "general law s” of change a n d study (their interaction; ra th e r I tr y to illum inate th e complex fab ric o f developm ent w h ere I can, using ce rtain general principles as tools for th is w ork. Professor Price has helped m e to see th e difference betw een th is approach a n d th a t of o u r M arxist colleagues. L et u s u n d erstan d th is difference clearly, or else we m ay find ourselves having n o com m unication.
I sh all give an exam ple of m y “em pirical” approach to th is problem, b u t first m ay I suggest a refin e d term inology fo r dividing betw een perio'ds in th e h isto ry o f science. In stead of try in g to f i x . th e startin g point o f a new developm ent, we m ay speak of “anticipation”, “penetra tion” a n d “dom inance”.
M y exam ple m a y b e 'Called “Social A spects of M odern European N atu ral Science”. I sh all consider th e n a tu ra l periodization of differen t aspects of th is activity, a n d see w h at is revealed by th e intersection of th e d ifferen t intervals.
F irst le t us ^consider science as a basic m eans of production. Here we find “anticipation” in Bacon, and tin th e early Royal Society. “Pene tration” begins slowly, becoming effective on a m ass scale only tow ards th e end of th e X lX th century. “D ominance” 'dates from 1945. Correspond
ing to th is aspect, w e have th e position of th e com m unity of science. Up to th e la st w a r it w as on th e m argin of society, aw ay from th e centres of power. Since then, w ith science as th e basic m ean s of produc tion, th e com m unity of science h a s been a t th e centre.
B ut th e prehistory of science does not end in 1945; let us consider the aspect of “ideology”. I take, for simplicity, the attitu d e th a t th e study of inanim ate n atu re is th e key to tru th . For this, “anticipations” are in Bacon, and continuous traditions s ta rt w ith th e’schools of D escartes and Galileo.
For th e organization of th e com m unity of science, th e X V IIth cen tu ry “anticipations” a re realized only a t th e end of th e X V IIIth century, w ith th e foundation of th e Boole Polytechnique.
Considering a ll th ese aspects to g eth er on a tim e-scale, w e notice a n interesting featu re of th e p eriod "between (the F rench Revolution and th e Second W orld War. Then, th e com m unity of science existed, self-contained, on th e m arg in of society, w ith a n effective ideology. P erh ap s o u t of such a (social situ atio n cam e th e a ttitu d e of “poire science” w hich h as conditioned teaching and ev aluation of science un til so v ery recently.
Discussion 239
The above sketch As dangerously oversim plified. N ot o n ly are m y categories crude, b u t I have ignored national differences of trad itio n an d o th e r approaches to th e understanding o f mature. Im p articu lar, th e “hylozodstie” trad itio n of th e Renaissance, reapp earin g as G erm an “N a- turphilosophie”, w hose significance h as been seriously underestim ated.
A . P. Y ou ch kevitch
Professor Olszewski co rrectly raises a series o f problem s concerning th e periodization of th e h isto ry of science. The a tte m p t to periodize th e general h isto ry of n a tu ra l amd m athem atical sciences, as suggested by Professor K edrov, deserves m uch attention. M any principles recom m ended by him are correct. The concrete characteristic of p a rtic u la r periods, however, gives rise to objections.
This applies, first of ail, to th e period A, defined by P rofessor K edrov as a natural-philosophic period — /when th e ru d im en ts of n a tu re ’s knowledge a re p a rt of a single, u n d ifferen tiated philosophical science. K edrov extrapolates (the peculiarities of th e b rief developm ental epoch of G reek th o u g h t over th e w hole of th e A ntiquity. Was, how ever, the astronom y of Babylonians natural-philosophic? Was th e en tire m a them atics o f Greeks, th e ir 'statics amd hydrostatics, th e ir astronom y a n d so fo rth a p a rt of philosophy and w as the natural-philosophic m ethod of thinking really p ecu liar to- them ? B ut th e m entioned sciences d id play a leading role in th e G reco-Roman w orld. If I am allow ed to delineate th is period A w ith tw o o r th re e words, I should say th a t it was a period of form ation of n a tu ral and m athem atical sciences in th e tru e sense of this word.
The period a was — according to P ro fesso r K edrov — a scholastic one, in w hich the false sciences astrology, magic, alchem y a n d oth ers w ere prevailing. It is tru e th a t th is was th e period of scholasticism dom inating in philosophy an d th a t scholasticism ex erted 'influence on science. O n th e o th e r hand, th e re developed m athem atics, astronom y, mechanics {Oxford and Paris) a n d son on. The developm ent of cognition was n o t so sim ple amd so one-sided a process. T h ere as, besides, no reason to oppose — as Professor K edrov does —• Europe to M ussulm an countries. The philosophic amd theological scholasticism , ham pering th e progress of science, and th e stru g g le of th e progressive scientific th o u g h t against th e fo rm er existed both in C h ristian and M oslem countries.
A t last, n o t quite fo rtu n a te w as th e denom ination of th e p erio d B as em pirical a n d collecting. This m ay be a ttrib u te d to th e -cycle of biological sciences, b u t n o t to science as a w hole. In th a t period, th e leading ro-le w as being alread y 'played by th e com plex of m echanical- -m athem atical an d in p a r t physical, th a t is theoretical sciences.
