C I N Q U I È M E P A R T I E DISCUSSION
I. Szum ilew icz
A lthough m y own field is n o t h isto ry o f science 'but philosophy of science, I am, of course, ex trem ely in tere ste d in th e h isto ry of science, because I do believe th a t a historical approach to th e philosophy of science is a v ery good one. My im pression from ou r m eeting is th a t th e historians of science need to cooperate a n d iso do th e philosophers of science. A nd I believe th a t such a cooperation m ay be v ery useful for both sides. T here is of course nothing new in th e idea th a t th e problem o f classification and periodization of science is a v ery difficult an d complex one. T here a re m an y causes o f it. L et me lisrt som e of them .
1) We should choose a set of methodological 'postulates, b u t such postulates laire based on th e acceptance of some theories a n d philosophical conceptions, o r are calling to th e common sense m eanings. O ur choice of th e set of postulates h as th erefo re some a rb itra ry elem ents. We m ay choose how ever a m etapostulate so th a t the set of postulates should give us the picture of th e objective tre n d a n d developm ent o f science. B ut such a basic metapostuHate contains, of course, some a rb itra ry elem ents, too.
2) We should h ave a th eo ry of definition, and a definition of w h at is science, w hat is its subject, a n d iwhait m ethods it is using. A il th a t is, w e know v ery well, a v ery complex problem , 'connected o f course w ith th e w hole body of social activ ity of men.
3) We should choose a se t of crite ria of development, a n d th e pos sib ility of m aking a choice is here of great diversity. This m ay be, for exam ple, a criterion in science itself, o r in its ex tern al rela tio n s to o th er branches of h um an activity. To quote a n exam ple fro m th e first one: we m ay say th at th e sign of a new period of science is th e d if feren tiation a n d change of isome fun dam ental notions, for exam ple, th e bifurcation of th e notion of m ass into in e rtia l m ass a n d grav itatio n al mass, and th e evolution of tim e an d space concepts; th is is th e criterio n of th e great tu r n from N ew ton’s to E instein’s physics. B u t (within th e problem arises th e question of how m any of th e te rm s sh ould be changed to decide th a t a new period has begun, and, of course, a host o f o th e r questions. A good exam ple of a criterio n based on e x tern al relatio n s is
230 La périodisation de l’histoire de la science e t de la technique
th e influence of one science upo n o th e r sciences or 'branches of cu lture an d social activity, for instance, th e influence of th e second law of therm odynam ics a n d of th e notion of en tro p y upon chem istry, biology and philosophy.
4) I t has to b e show n how th e group of problem s .works. Of course, we should stress th a t w hen m aking a choice of one set of methodolog ical postulates,, definitions of science, criteria of development^ we do choose a p a rtic u la r fram e, and th e re exists a h o st o f various fram es. A nd I doubt w h eth er th e ilaws a n d reg u larities of (|o r exam ple) developm ent of science are going to be in v a rian t to observers in various fram es. We should rem em ber th is w hen introducing a p a rtic u la r observation fram e.
L e t us now exam ine P rofessor K edrov’s p ap ers on periodization a n d classification from thiils general p oin t of view. I t is possible to m ake some rem arks.
1) We do n o t know from th e p aper w hich definition of science does Professor K edrov accept.
2) The developm ent is defined as th e w ay from sim ple to' m ore com plicated sub jects a n d laws. B ut th e n a problem arises —• w h at th e te rm ‘^simple” m eans. The principle of sim plicity, to use a paradoxical phrase, is a v ery com plex one. W hat precisely the te rm “sim ple” means, w h at is the definition of sim plicity? There a re various concepts of sim plicity. For exam ple, Professor P o p p er claim s th a t w h a t is in tu itiv ely th e sim plest of various alte rn ativ e hypotheses is also alw ays th e most falsifiable one. A nother 'point o f view, commonly accepted An th e intel lectual com m unity, is th a t “sim plicity” m eans n o t to m u ltip ly unne cessarily th e entities adm itted in to one’s theories. There exist m any aspects of ^simple” ; in which of th e m this te rm is used by Professor Kedrov? In a logical,, epistemological, ontological, pragm atical one, etc.? Besides Professor K edrov claims th a t th e developm ent o f science is going from “sim ple” to “com plicated”. B ut th e re exist some v ery serious argum ents th a t th e tre n d of th e 'development of science is going in an opposite direction, from com plicated to simple. A nd some of th e philo sophers of science claim th a t it is a sign of th e underlying sim ple stru c tu re of n a tu re itself.
3) P ro fe sso r K edrov 'proposes to divide th e developm ent of science into five p arts: A, B, C, a n d tw o periods in betw een A a n d B, a n d B an d C. Tlhe p a rt A, if I u nd erstan d correctly, is a n observational part. B ut it should be clarified w hat observation m eans. P u re observation does n o t exist. S olitary p u re facts a re a m y th th a t has been rejected by the philosophy of science. The period B is an alytical a n d C — synthetical. A nalysis, according to the author, m eans to divide th e w hole body of science in to p articu la r branches, a n d C is a period of 'integrating them . "B ut the processes of analysis and synthesis a re still going on. The old
Discussion 231 branches of sidemce a re undergoing a process o f bifurcation, b u t w e do observe a process of in teg ratio n too,, some branches of science being joined in one, as for exam ple in th e case of cybernetics:.
Professor K edrov claim s besides th a t th e co ntem porary science is undergoing a process o f integrating, because w e observe th a t in betw een tw o sciences as for exam ple physics a n d chem istry th e re appears a n ew branch — physical chem istry. Buit th e process of in teg ratin g is, I think, a v ery specific one, as no individual is ab le to have an outlook o n th e whole body of science. Such an outlook is like a platondc idea — it exists for the m ankind a s a w hole, b u t a n individual is today fu rth e r from catching it, th a n ever in th e h isto ry of m ankind. T h e developm ent o f science is very, v ery rapid; a physicist, for exam ple, cannot g rasp th e w hole of physics. P ro fesso r O ppenheim er quoted as an exam ple th a t h e h ad ta k en p a rt in a sym posium of physics w h en th e fun dam en tal p ap er w as understood only b y v ery few p articip an ts of th e m eeting. A n in te grating outlook on th e whole body of science is: therefore fo r a n ind i vidual of our itdme a platonic idea.
I suppose th a t th ese rem ark s are a n exam ple o f th e usefulness of collaboration betw een historians and philosophers of science. Prof. K edrov’s paper seems to me essentially right, b u t it w ould be necessary to clarify such concepts as simplicity, analysis a n d synthesis and th e understanding of th e logic of choosing the explanatory postulates.
E. Rosen
A ccording to P rofessor Olszewski, periods in political h isto ry a re sharply defined, w hereas periods in the h isto ry of science a n d technology a re n o t sh arp ly defined. B ut in political history, som e periods a re n o t sh arp ly defined, for instance, th e fall of th e Roman Em pire. A nd in th e history of observational astronom y, we know th e year a n d th e day, a n d v ery n e a rly th e m inute, When th e period of telescopic observations began. The sam e m ay be said also for th e beginning of th e period of radio astronom y.
A. A. Z vorykin e
P rofessor Olszewski’s le c tu re a ttra c ts th e atten tio n of a ll th e hi storians of science a n d technology as both from th e th eoretical a n d p ractical point of view every scientist — w h en prep arin g w o rks con cerning th e histo ry of science and of technology — ought to resolve in
