Problem of periodization in the history of natural science

COMMUNICATION S

B. M. K edrov

PROBLEM OF PERIODIZATION IN THE HISTORY OF NATURAL SCIENCE

FORMULATION OF THE PROBLEM

t '

1.

The problem of periodization iis, stric tly speaking, a problem of the in tern al s tru c tu re of historical process, th a t is of th e s tru c tu re o f its presentation, too. Hence follows th e theoretical im portance and practical significance of th a t problem for th e w hole historical science and for all1 of its divisions, including th e h isto ry of n a tu ra l science.

2.

The period in th e history of science is called a d eterm in ed stage or phase of its developm ent characterized by th e w hole com plex of stable specific indications appearing at its rise a n d disappearing at its com­ pletion, ow ing to w hich th e historical boundaries of each p eriod a re showing u p m ore oir less clearly.

3.

Such indications o f each period are first of all: u niversal m ethod of cognition o r of approach to th e investigation in n a tu re ’s phenom ena, th a t is existence of determ ined research m ethods ch aracteristic of a given p eriod a n d playing a decisive role d u rin g th e w hole of th a t period; general taisiks confronting th e n a tu ra l science as a whole, a n d its p articu la r branches d u rin g a given period; general technological an d in d u strial needs d eterm ining th e m ain directions of n a tu re ’s cognition.

THE TWO APPROACHES TO PERIODIZATION 4.

The formail approach to the problem of periodization is founded on a superficial consideration of m ost sim ple an d strik in g signs a n d connections, w hich .do n ot reflect, how ever, th e essential reg u larities ORGANON, 1964

208 B. M. K edrov

an d th e in tern al contents of th e process being analysed. Of form al character is th e periodization: according to p u re ly chronological indica­ tions, for instance according to cen turies (science of th e XVIItlh, X V IIIth, X lX th, X X th centuries) o r according to historical epochs (A ntiquity, Middle Ages, Renaissance and so forth); according to socioeconomic stru ctu re s only {science of slave-ow ning society, of feudal society and so on) w itho ut in q u irin g into th e peculiarities of th e developm ent of science'itself in ev ery stru ctu re ; according to th e p articu la r p rom inent discoveries, snatched from tjie whole process of developm ent (science of steam age, electricity age, atom ic age etc.); according to persons, w ith w hom great discoveries a re connected (Copernicus’s epoch, N ew ton’s epoch, D arw in’s epoch -etc.).

5.

A su b stan tial approach does n o t confine itself to external, form al indications (for instance, b y re fe rrin g science to one o r an o th er hi­ storical epoch), b u t req u ires a penetration into th e essence of the process being analysed, in to th e profound, fundam ental ties an d in te r­ dependencies that, in the final analysis, determ ine the changes of the individual stages and phases of th e developm ent of science, and con­ sequ en tly its periodization. Only such a n approach is M arxist.

THE FACTORS DETERMINING PERIODIZATION

6

There a re three m ain factors determ ining th e division of th e history of n a tu ra l science into- periods: re g u la rity of th e process itself of n a tu re ’s cognition (its in te rn a l logic); its direct dependence on technology, oh industrial and agricultural production, and on medicine; its dependence on th e general developm ent of socioeconomic relations a n d on th e character of th e class struggle, especially in the dom ain of ideology — which exert an influence upon th e n a tu ra l science both directly and th ro u gh th e dom ains contiguous to it (philosophy and technology).

7.

Science m ay not be reduced to a p u re cognition of nature, for i t is organically interw oven w ith practice w hich stim u lates its development, serves as a criterion for it, and constitutes th e ultim ate end of th e cognition. In a broad sense of th e w ord, th e w ay of n a tu re ’s cognition conducts from the em piric observations and experim ental inquiries, through theoretic (logical) com prehension and generalization of w hat has been observed, to th e practical activity a n d utilization in tech­ nology, in production, of What has b een disclosed a n d discovered by

science. N atu ral science, therefore, is in separably connected w ith philo­ sophy and technology, an d th ro u g h th em — wiitih life and developm ent of th e whole society.

8

.

In spite, however, of the v ery im portance of connections of n a tu ra l science w ith technology (and through it — w ith th e in d u strial production) a n d philosophy (and through it — first o f a ll w ith th e ideological class struggle), those connections do n ot fu lly determ ine y et th e concrete content of th e p articu la r periods of science developm ent. Being a cogni­ tion of a determ ined object (nature), science a s a specific phenom enon and its stages (periods) are characterized above all by tw o factors: b y general tra its of th e stages of every cognition an d b y th e d eg ree of cognizing a determ in ed object, th a t is by th e degree of revealing the. regu larities of n atu re . The first factor is expressed b y th e m ovem ent of ev ery cognition from th e phenom ena to th e essence a n d from th e less profound essence to th e m ore profound one; th e other is expressed by the specificity of th e m anifold essence being disclosed, a n d of its m anifestations. B oth factors together determ ine the in te rn a l logic of th e developm ent of n a tu ra l science itself.

9.

Accordingly, th e characteristic of p a rtic u la r periods is to be founded upon th e contem plation of th e m u tu al bond existing betw een th e in te rn a l logic a n d th e ex tern al conditions of science developm ent.

THE THREE PHASES OF NATURE’S COGNITION (SCHEME ABC) 1 0.

F rom th e p o int of view of th e in tern al logic, th e cognition of n a tu re is characterized b y th e general course of development, w hich conducts: 1) from th e d irec t contem plation of n a tu re ’s phenom ena, 2) th ro u g h th e analysis of n atu re , 3) to th e synthetical reco n stitu tio n — on th e basis of th e p a rticu la rs cognized — of th e p ictu re of n a tu re a s a whole.

11

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To th e th re e stages of ev ery cognition (lively contem plation, analysis, synthesis based on the previous analysis) correspond th re e phases of developm ent of th e en tire n a tu ra l science:

A. iPhase of contem plation: n a tu re is reg ard ed as a w hole direct a n d n o t dism em bered into p arts; the general overshadow s th e p articulars,

B. Phase of analysis: n a tu re is sh a rp ly divided in to p articu la r dom ains; its objects are being anatom ically dissected, a n d to this effect, immobilized, isolated a n d d ep rived o f life; th e rev erse joining of th e K H N iT „ORGANON“ — 114

210 B. M. K edrov

division d e m e n ts does not ta k e place or 'has a superficial ch aracter only; th e p articu lars overshadow th e general.

C. Phase of synthesis: n a tu re is 'being once m ore reg ard ed as a whole, yet n ot sim ply a s som ething undivided, b u t as som ething originated by w ay of an in te rn a l interactio n of its p arts; th e w hole tis being recon­ stitu te d o u t of th e p a rts b y settin g them in to m ovem ent a n d b y reviving th e objects fo rm erly im mobilized a n d deprived of life — th a t is to say by binding to g eth er w h a t w as d isu nited before; i t is fo r th e first tim e th a t th e general and th e p articu lars ap pear in a n organic unity.

In th e typical case, phase A is being rep resen ted by th e ancient science, phase B — b y th e science o f th e X V IIth c e n tu ry and of the first half of the X V IIIth century, phase C — b y th e contem porary science.

TRANSITIONS BETWEEN THE FUNDAMENTAL PHASES OF COGNITION

12.

T h e schem e ABC has a n extrem ely general b u t a t th e same tim e one-isided character, because i t does not ta k e into account th e connec­ tions of science w ith practice. As a m a tte r of fact, such phases as A, B, C do 'not ap p e a r in a p u re form. They hav e b een singled out ab­ stractly, by m eans of a logical analysis onily. M oreover, th e scheme u nd er consideration does not em brace, stric tly speaking, m an y im portant epochs of th e h isto ry of science (Middle Ages', Renaissance, th e second h alf of th e X V IIIth a n d th e w hole of the X lX th cen tu ry a.s.o.). That is w h y th e scheme ABC req u ires a fu rth e r elaboration an d concrete defini­ tio n th rough explaining th e dependence existing betw een th e form ation of new periods w ithin n a tu ra l science and th e e x tern al conditions of science developm ent as w ell a s needs of technology a n d 'production.

13.

The progressive m ovem ent of cognition is proceeding u n d er th e d irect influence of practice. T he causes determ ining th e v ery progress of science — req u irem ents of technology a n d production — determ ine a t th e sam e tim e th e historical te rm s of th e n a tu ra l science passing from one period to another. A s a re su lt of th a t, th e tran sitio n from one phase of cognition developm ent to another m ay la st m an y decades and even centuries, unless th e m otive forces of science developm ent a tta in a n appropriate level.

14.

The sociopolitical conditions m ay now stim ulate, now h am per th e science developm ent; th e y m ay occasion w ithin it n ew contradictions o r favour their solution. In consequence of th e influence exerted by

the im peding ex tern al conditions, th e im m inent tran sitio n of cognition from one phase to another, in accordance w ith th e schem e ABC, m ay­ be ham pered or even tem porarily receive a w rong (direction.

FULL SCHEME OF PHASES OF SCIENCE DEVELOPMENT AND OF TRANSITIONS BETWEEN THEM

15.

U nder th e influence of nonnscientific causes im peding th e tran sitio n s of cognition from one stage to another, th e above transitions had been ham pered, in course of history, a n d tran sfo rm ed in to m ore o r less independent and prolonged in term ed iate periods :

a. The tran sitio n from contem plation to analysis1 w as ham pered in th e age of feudalism b y th e prevalence of religious ideology a n d b y th e absence of sufficient stim u li of technological progress — w hich led to th e form ation of a special in term ediate period.

b. The tran sitio n from the analysis of n a tu re to its sy n th etical com­ prehension became com plicated in th e X lX th century, in th e era of capitalist dom ination, by th e ideological-political a n d philosophical reaction of th e bourgeoisie, w hich equally th e n co n tributed to th e form ation of a really special in term ediate period.

Accordingly, th e schem e ABC is being tran sfo rm ed in to a m ore detailed scheme AaBbC, w h ere tw o interm ediate, tra n sito ry periods a, b have b een included.

16.

Thus w e received alto geth er five periods w ith specific m ark s: I period, phase A; II — tran sitio n a fro m A to B; III — phase B; IV — tran sitio n b from B to C; V — phase C. Since n a tu ra l science, as a science in th e tru e sense of th e word, appeared n o t before th e Age o f Renaissance, th e tw o first periods h av e fo r th e w hole n a tu ra l science (but not for some of its branches) a pre-scientdific, em brional character, an d only th e th ree following ones — a scientific, in fact, a developed character.

17.

Owing to th e dependence of science developm ent on th e developm ent of th e entire society, all th e above periods m ust, in th e end, correspond (m ore o r less exactly of course) to th e fu nd am en tal periods of general history. Each period in its ow n developed form corresponds e ith e r to a determ ined socioeconomic system, o r to its special phase, to a sep arate stage. Chronologically, however, th e revolutions in th e view s on n atu re , w hile con stitu ting in fact th e bounds betw een th e periods of th e h isto ry of science, do n o t com pletely correspond to social revolutions n o r to o th e r great tu rn in g-po ints in th e h isto ry of th e e n tire society.

212 B. M. K edrov

EMERGENCE OF A LEADING SCIENCE

18.

The in te rn a l logic of science gets determ ined m ore in d etail by th e course of, th e developm ent of cognition from m ore sim ple objects (movement form s a n d th e ir regularities) to m ore com plex ones. The notion of sim plicity hais in th is case both a n objective m eaning (as a correspondence to th e low er stag es of n a tu re developm ent), and a subjective one (in th e sense of its g reater accessibility to cognition and utilization by man). In conform ity 'with that, th e developm ent of n a tu ra l science began from th e m ost sim ple a n d easily cognizable form s of th e moving m atter, an d proceeded to w ards inquiring into forms m ore and more complex, less and less accessible to cognition a n d utilization. It is ju st w h at determ ined the successive developm ent of various branches of science and th e application of th e ir achievem ents in technology. The fact th a t in th e course of science developm ent such o r o th e r scientific branches o r problem s a re coming to th e fore, is to be explained by technological needs of society.

19.

Accordingly, the dom inating ro le of a leading science in th e p articu lar periods of n a tu ra l science w as being acquired successively by its one or an o th er developing branch: m echanics in th e 3rd period (hence one of its denom inations: “m echanistic science”); chem istry of com pound substances a n d physics at th e beginning of th e 4th period a n d biology — a t its en d (hence one of its nam es “steam an d D arw in c e n tu ry ”); atom physics, th e n q uantum and n u clear (subatom ) physios a t th e beginning of th e 5th period (hence th e nam e: “centu ry of nuclear en erg y ”) and lately, at th e contem porary stage of th e 5th period, physics of elem entary particles, cybernetics, cosmonautics, m acrochem istry a n d m olecular biology. The developm ent of science, w ith that, takes place in th e fol­ lowing w ay: all th e branches of science, w hich h a d arisen before, keep on developing, b u t to th e forefront are advancing th e branches th a t have ju st come into 'being in th e course of n a tu re cognition as a new, a higher stage of th e developm ent of n a tu ra l science as a whole.

CONCRETE PERIODIZATION 20.

In order to d eterm ine m ore concretely th e characteristic peculiarities of the p a rtic u la r periods of th e history of science, it is necessary to explain th e general featu res of each of them fro m th e view point of: general approach to th e study of n a tu ra l phenom ena (scientific m ethod

o r w ay of thinking); a u th o rity of one or ano th er philosophy, fostering o r ham pering th e process of know ledge; leveil a n d ch aracter of th e developm ent o f th e technology and of its inquiries; basic contradiction of th e n a tu ra l science rem aining 'in force during a given period. In con­ form ity w ith th a t, a m ore concrete nam e a n d definition m ay be given to each period underlying th e scheme AfflBbC.

FIRST PERIOD (A) 21.

The basic period A w as characterized by a general natural-philosophic w ay of thinking and an adequate approach to n atu ra l phenom ena, since th e rudim ents of n a tu re ’s know ledge form ed p a rt of one a n d indivisible philosophic science. T h at w ay of thin k in g was, in its foundations, n aiv ely dialectic a n d a t th e sam e tim e naively m aterialist. Technology w as still v ery little developed, and accordingly could not visibly stim u late th e developm ent of n a tu re stud y n o r «create conditions fo r a n in evitable appearance of a system atic-experim ental and all th e m ore theoretical n a tu ra l science. The fundam ental contradiction of th a t p eriod w as a deep chasm betw een broad natural-philosophic conceptions an d ex trem ely prim itive experim ent and production habits, giving n o pos­ sibility of hoarding facts exactly established a n d checked.

SECOND PERIOD (a)

22

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The interm ediate period betw een th e phases A an d B, especially in th e conditions of th e feudal West, w as characterized b y th e scholastic w ay of thinking, w hich elim inated or stro n g ly restric ted a n d d isto rted th e experim ental approach to n a tu ra l phenom ena. T he dom inating religious ideology reduced science to a serv an t of its own; as a re s u lt of religious conceptions p en etratin g into science, which already before (pegan differentiating in to p a rtic u la r branches, it degenerated in to peculiar, sem i-scientific an d sem i-religious hy brid s (astrology, alchem y, cabalism, m agic etc.).

Technology still developed so slow ly th a t its influence could n o t p ro tect science ag ainst th e pernicious effect o f religion and scholasticism. The m ain contradiction of th a t period was a n u n n a tu ra l com bination of th e not y et Shaped science w ith th e w orld outlook a n d w ay of th in k in g com pletely inim ical to it. Sporadic sp ro u ts of science appeared and w ere cultivated in the E ast (Arabs, C entral Asia, Tramscaucasus etc.).

214 B. M. Kedrov THIRD PERIOD (B)

23.

The fundamental! period B w as — a t its 'beginning — characterized by: rap id ly proceeding an d profound differentiation of th e form erly u n ited science into p artic u la r branches1 (mechanics, astronom y, physics a.s.f.); violent «(revolutionary) d e p a rtu re from religion a n d scholasticism; developm ent of experim ental investigations enabling th e accum ulation of em pirical data, th e collection of facts indispensable for th e ir sub­ sequent generalization, th a t is fo r building th e foundation of th e science itself. The n a tu ra l phenom ena w ere cognized by m eans of an analysis w ith o u t considering th e ir general connections a d th e ir development. Form al '(artificial) classifications cam e in to being. All th a t constituted a cognitive prem ise for th e subsequent cognition of n a tu re in its con­ nections a n d changes. Such a n analytic approach, however, being one­ -sidedly im m obilized and m ade absolute, led to a m etaphysical w ay of th in k in g w hich sup p lan ted th e original naive «dialectics. But every m etaphysics, as a m a tter of fact, is a gnosiological source of idealism and theology '(“in itia l im pulse”, “creative acts”) in 'spite of the prevailing general m a teria list w orld outlook. H ere is th e fundam ental 'contradiction of th a t period to b e sought: n a tu ra l science, a t firs t revolutionary and breaking w ith religion (discoveries of Copernicus), la ter o n proved to be logically incapable of overcom ing theology, n a tu re being regarded by it as conservative throughout. Technology, in d u stry {just having arisen) exerted a very stim ulating influence upon science, p u ttin g before it th e task of stu dy in g th e m echanical form of m ovem ent as a funda­ m en tal one in th e conditions of m anufactory.

FOURTH PERIOD (b)

24.

The interm ediate period b betw een th e phases B an d C was ch aracter­ ized by th e overcom ing of th e m etaphysical w orld outlook th a t was endowing n a tu re w ith a n absolute invariability. Spontaneously, "without scientists’ know ledge a n d in sp ite of them selves, n a tu ra l science w as being p e n etrated by an essentially dialectical view upon n a tu ra l proces­ ses. It is in th e evolutionary conceptions th a t w ere reflected th e ideas of developm ent a n d of general connections in n atu re . Those ideas in tru d ed in to sd en o e a t first in some p a rtic u la r points {discoveries of Lomonossov, K ant, K. Wolf, Boscovich), m aking breaches in the previous fossilized view on n atu re . In th e evolutionary conceptions, successively p en etratin g into astronom y, chem istry, geology, physios, biology, w as reflected a new m ethod of n a tu re stu d y (com parative m ethod in anatom y, physical geography, chem istry; historical m ethod

in cosmogony, geology, biology a.s.o.); it p e rm itted to realize th e th eo re­ tical synthesis w ithin th e p articu la r branches of n a tu ra l science by em bracing th e w hole of th e stored experim ental m ateria l from th e view ­ point of a u n ified th e o ry an d n a tu ra l classification, a n d eq u ally betw een various branches of science th an k s to th e fact th a t th ey h ad been p en etrated b y th e general ideas of developm ent an d of m u tu al con­ nections. T hat synthesis, how ever, w as not y e t 'Complete since th e p articu lar branches of science rem ained d isu nited a n d th e ideas of developm ent and of m utu al connections did not p en etrate into th e m ost general form s of being and th e most elem en tary objects of n a tu re con­ stitu tin g th e foundation o f n a tu ra l science. The em pirical task rela tiv e to the collection of m a teria ls being in th e m ain fulfilled, th e tran sitio n to th e n ex t task — to a theoretical1 generalization — was perform ed. In view of that, th e hypothesis 'became a • form of science developm ent, a p u rely em pirical tho ug h t proved to b e contracted a n d inadequate, th e im portance of theoretical th o u g h t w as visibly increasing. A t th e sam e time, th e connections of science w ith practice, technology a n d pro­ duction w ere extending and consolidating. T he m ain scientific tre n d w as determ ined by th e first technological rev o lu tion (replacem ent of th e hum an hand by th e machine, utilization of steam in th e steam - -engine). This involved th e necessity of solving the problem of en erg y conversion, etc. The introduction of th e dialectical m ethod, as adeq u ate to th e n ew contents of science, proved to be an u rg en t necessity. The scientists, how ever, w ere hindered fro m shifting to th a t m ethod b y th e reactionary ideology of bourgeoisie w hich h ad grow n a ru lin g class. This gave rise to a fundam ental contradiction of th a t period — to a contradiction betw een th e new objective (dialectical) content of scien­ tific discoveries and th e fo rm er subjective (metaphysical) w ay of thinking. It is ju st w hat accounts fo r the num erous p a rtic u la r difficulties of th e X lX th cen tu ry science.

FIFTH PERIOD (C)

25.

The fundam ental period C is characterized by th e m arks of a fully developed theoretical synthesis: p e n etratio n of th e idea of connection a n d developm ent in to th e dom ain of elem en tary objects of n a tu re an d general form s of being; in terp enetratio n of form erly isolated branches of science an d sim ultaneous form ation of new, interm ediate and tra n si­ tory branches (cybernetics included), wlhich realize th e general in teg ra­ tion of science; extension of mature stu d y in both directions — to w ards m icro-objects and m acro-objects. The attain m en t of th e phase C was connected w ith th e m ost recen t revolution in science opened w ith th e discovery of R oentgen rays, rad io -activity (H. Becquerel), electron (J. J. Thomson), rad iu m (P. C urie and M. Curie-Sklodoiwska). In th e X X th

2 1 6 B. M. K edrov

century th e revolution 'in physics w as represented, am ong others, by 'Planck, R utherford, Einstein, Bohr. The connection of science w ith production grew even closer. The second technological revolution has p u t new task s lin k ed w ith th e transm ission o f h u m a n b ra in functions to a steering m achine (a cybermetical device). T h e pow er base o f p ro ­ duction has w idened considerably: i t w as a t firs t electricity (dynamo) an d chem istry (com bustion engines) th a t got ahead, la te r on — atomic energy (reactors). Cosm onautics cam e into being. There began the penetration into the chemism of life, bringing us n earer to th e solution of th e problem of biosynthesis.

26.

A lthough dialectics grows m ore a n d m ore indispensable, th e condi­ tions of im perialism give rise to additional difficulties in th e m a tter of scientists’ tran sitio n to it, th e grow ing activeness of th e reactionary (idealistic) w orld outlook being one of those difficulties. That is w hy science is seized w ith crisis w hich m ay b e reg ard ed as a separate, p a ra l­ lel p erio d C, coming in to p la y in th e countries of th e contem porary capitalism . Its fundam ental contradiction is a fu rth e r developm ent and aggravation of th e contradiction of th e preceding period b: owing to the spontaneous (unconscious) character of dialectics, th e commenced tran si­ tion from m etaphysics to dialectics is being exploited by th e reactionary ideology w ith a view to o ust m aterialism from science an d replace it by idealism. Consequently, the reactionary encroachm ents are being engendered by th e rev o lu tio nary rem aking of science, th e backw ard m otions — by its ra p id progress.

27.

T h at contradiction (th e reaction sponging on revolution, regress on progress) is being solved in th e conditions of socialism; it is for the first tim e th a t a n accordance is being a tta in e d here betw een th e form (way) of scien tists’ th ought a n d th e objective contents of th e scientific 'disco­ veries them selves. D ialectics becomes a research m ethod, consciously recognized b y th e scientists; science gets free from th e form er an ta­ gonism existing in capitalism betw een science and production, an d (in th e course of th e building of communism) tu rn s, in full m easure, into a direct productive force.

GENERAL RESULT OF PERIODIZATION

28.

On th e basis of th e w hole com plex of general m arks, each period m ay be characterized as follows:

I. A. N atural-philosophic (from A ntiqu ity to th e IV th cen tu ry A.D.) II. a. Scholastic (V th—X V th century)

III. B. Collecting o r em pirical i(XVIth—X V IIIth century) IV. b. Evolutional o r theoretical (X lX th century)

V. C. Of new est revolution o r contem porary (X X th century). 29.

W hen approaching th e sam e periods in a purelly m ethodological m anner, each of th e m m ay be characterized from th e view point of th e predom inant w ay of thinking an d o f th e influence of philosophy on science. In doing so, th e re a re two parallel periods to b e distinguished w ithin th e fifth period:

I. A. N aively dialectical II. a. Scholastic

III. B. M etaphysical (mechanistic)

IV. b. Spontaneously (inconsequently) dialectical V. C. Of crisis in science

Consciously (consequently) dialectical.

THE DIVISION OF PERIODS INTO STAGES

30.

At a m ore detailed periodization of th e h isto ry of science, each of its periods m ay be generally divided into three stages: e a rly (pre-clas- sical), w h ere th e essential m ark s and contradictions of th e preceding period did n o t yet fu lly disappear an d those of th e beginning one did n o t y et fu lly tak e shape nor m anifest them selves; m iddle o r principal (classical), w here th e essential m ark s a n d contradictions of th e given period developed in full; late (post-classical), w h ere a p a rt from th e essential m ark s and contradictions of th e given period, th e m ark s of th e n ex t period begin coming to lig h t (arising). In ce rta in cases th e nu m b er of stages m ay be greater o r sm aller. The existence of those stages shows th e absence of a n y sharp bounds b etw een th e periods a n d the gradual change (developm ent) fro m one period to another.

CONTRACTION OF THE PROBLEM:

PARTICULAR BRANCHES OF SCIENCE AND PARTICULAR COUNTRIES

31.

The general theses and principles o f periodization of th e w orld science as a w hole m ay be adopted fo r th e periodization of its individual branches, divisions a n d tre n d s a s w ell as for th e developm ent of science in th e p articu la r countries. W ith th at, th e following marks, a re coming to light: th e m ore detailed, the m ore n arro w is th e c h ara cter o f a branch o r o f a tre n d w ith in th e science, th e m ore profound is — a t th e d eterm i­ nation of th e app ro p riate periods — th e influence exerted b y th e in te rn a l

B. M. K edrov

logic of th e developm ent of 'cognition an d by th e specificity of th e object u n d er exam ination; th e periodization o f th e h isto ry of science in p a rti­ cular countries is, on th e contrary, characterized by th e periods being dependent on ex tern al, socioeconomic conditions — so th a t th e periodiza­ tion approxim ates to th e general-historical periodization.

32.

A lthough th e periodization w ith in th e p articu lar branches of n a tu ra l science is, in th e end, being determ ined by th e periodization o f th e n a tu ra l science as a whole, th e bounds of periods i n general may not coincide. T hus for instance th e tran sitio n from th e th ird 'period to th e fo u rth sta rte d in astronom y in th e m iddle of th e X V IIIth c en tu ry (K ant’s cosmogonical theory), in chem istry of -compound substances — a t th e beginning of th e X lX th c en tu ry (atomism), in geology — in the th irtie s of th e X lX th c e n tu ry (theory of gradual developm ent of th e Earth), in physics — in th e forties (theo ry of energy conversion), in biology — in th e th irtie s a n d fifties (cellular theory, Darwinism), in chem istry of atom s a n d m olécules — in 'the la st th ird of th e X lX th cen tury (periodic table); to w ard the end of th e X lX th century, th e sharp boundary betw een physics an d chem istry began to be effaced and th e contem porary physical chem istry came in to being, as a founda­ tion for th e fu rth e r developm ent of b oth disciplines in th e X X th century. Finally, a radical breaking of the fo rm er fundam ental notions of m echanics (mass, space a n d time) an d of physical-chem ical disciplines (atom, 'molecule) s e t in only a t the tu r n o f th e X lX th an d X X th centuries. The g eneral succession, how ever, of th e altern atin g periods in th e history of p articu lar branches is th e sam e as w ithin th e n atu ra l science as a Whole.

33.

The principles of periodization of th e history of n a tu ra l science a n d its concrete scheme, p u t fo rw ard in th is m onography, rep resen t th e personal view s of the au th o r and are proposed for discussion w ith the view of elaborating a base for a M arxist solution of the question u n der consideration.