O R G A N O N 3(1966) MÉTHODOLOGIE GÉNÉRALE
Gabor Biro (Hungary)
PHENOMENOLOGY AND MODEL CONSTRUCTION IN THE HISTORY OF PHYSICS
“Physics alw ays m ust strive after a d irect description instead of an indirect one” says E. Mach, proclaim ing a program of “physical pheno menology, free from hypotheses”, at th e tu rn of the 19th and 20th c e n tu rie s .1 A lthough th e problem s of this M achian physical phenom eno logy are linked w ith K a n t’s contrasting of phenom enon and noumenon, the concept of phenomenology, however, entering physical lite ra tu re afte r Mach, is not identical at all w ith K a n t’s or H egel’s phenom eno logy, and is still less identical w ith th a t of Husserl. The essence of M ach’s physical phenomenology, being free from hypotheses, m eans th a t th e task of physics is solely to sum up and to describe (this being the phenomenology) the results of experim ental research, w hile ev ery in te r pretation, explanation, form ation of hypothetic models belongs to m eta physics, to a penetratio n behind the dom ain of physics.
The establishing of th e M achian phenom enological conception w as not independent of social and ideological interactions, w hile on th e other hand M ach’s positivism affected several later tendencies of neo positivism, such as the logical positivism, th e V ienna Circle or R eichen- bach’s school.
Machism or ra th e r neopositivism are v ery im pressive in th e in te r p retation of disciplines of m odern physics. This can not be sim ply ex plained by th e ideological attractiveness of these trends. The possibility of positivist effects should be founded on the characteristics of physics itself, on th e h istory of its progress. And as a m a tter of fact, certain prepositivist trends m ay be found in th e h isto ry of physics, long before philosophic positivism and M ach’s physical phenom enology appeared, and this not in form of secondary tendencies, b u t now and again as p re vailing trends.
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Exam ination of th e historical roots and the la ter consequences of neopositivism dem onstrates, th a t essentially the problem can always be reduced to a sharp, contrasting distinction betw een phenom enology and model.
The object of our paper is:
(a) to dem onstrate th a t th e contrasting of phenom enology and model is not correct a t all, neither from th e historical, nor from th e logical point of view. 2
(b) to reveal th e roots of this contrasting, in h eren t to th e historical developm ent of p h y sics.3
(c) to furnish d ata in order to prove, th a t in th e last analysis physi cal idealism of recen t times is also based on th e w rong com prehension of the relation of “phenom enology” and model, in spite of m any essen tial new features. 4
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a) Experim ent and m athem atics are inseparable m eans of physical research. Their relatio n w ithin physics can be com pared to the insepa rable connection of induction and deduction.
The inseparability of the descriptive and explanatory character of scientific t h e o r y corresponds to th e inseparability of experim ental and m athem atical m ethods. C e r t a i n laws of physics m ay be rath e r of a descriptive th a n of an exp lan atory character, b u t a scientific theory alw ays m eans th e logical in terp reta tio n of perceptible (experim ental) data, thus being always explanatory to a certain degree. Thus theory is alw ays also exp lan atory and not only descriptive.
B ut certain so-called d e s c r i p t i v e laws, also reveal reg u lar relations betw een certain phenom ena and groups of phenom ena, f u r n i s h i n g a l s o h e r e b y c e r t a i n e x p l a n a t i o n s concerning given groups of phenom ena, since the revelation of necessary connect ions a penetration behind th e surface. A lthough th e law s of Boyle- -M ariotte and Gay-Lussac, for instance, only describe th e relations be tw een volume, pressure and tem p erature of gases (ideal gases), they furnish h erew ith m ore about th e n atu re of phenom ena and th u s also supply some explanation about th e essential character of the gas it self.
2 D etails of this point are presented in: G. B i r ó : P henom enolo gy and Model. „Magyar Filozôfiai S zem le” 1965, 7.
3 The history itse lf is the best d en ial of the alleged divergence of phenom eno logical and m odel theory. The author investigated th e history of developm ent of th e principle of energy, of the concept of entropy and of the first physical atomic theory, from this point of view . See: „Fizikai S zem le” 1960, 6; 1962, 1; 1963, 3.
4 About th e latest tendencies of physical idealism see: G. B i r ó : Historical
Périodisation of Physical Idealism . See: „Épitoipari és K ôzlekedési Müszaki
Phenom en ology and M odel C on stru ction 1 0 7
The epistemological fact, th a t the laws of science reflect re a lity only approxim ately indicates, th a t law s apply to an idealized reality, to a model w hich is not identical w ith re a lity (only in th e approach given b y th e level of science).
In this sense e v e r y t h e o r y r e p r e s e n t s a m o d e l t h e o r y .
Thus, th e re is no epistemological difference betw een a th eo ry based d efinitely on models and a so-called “phenom enological” theory. Not only the fundam ental ideas of the phenom enological th eo ry contain abstraction and generalization as com pared w ith th e d irectly observable phenom ena, bu t even models are abstractions originating in observed phenom ena (e.g. the conceptions of atoms or molecules in th e kinetic theo ry of gases are abstractions which serve to describe the observable phenom ena, ju st as th e conceptions of tem p eratu re, pressure, etc. of the “phenomenological th e o ry ”).
b) The contrasting of phenomenological and model theories is w rong in view of logic and epistemology. All the same th is opinion has been voiced again and again since centuries in th e course of th e h isto ry of physics. This indicates th a t th e roots of such opinion m ust lie in the historical course of physics. Indeed, th e outstanding role of positivism in answ ering the epistemological questions of physics, is connected fundam entally w ith th e experim ental m ethod pertaining to th e very essence of physics. As a consequence, positivist tendencies appeared in connection w ith physics alm ost im m ediately afte r physics had become independent in m odern times.
The recent independence of physics ru n s parallel w ith the develop m ent of the particular experim ental m ethods of physics. The g reatest obstacle for the em ancipation of physics is scholasticism and its n atu ral philosophy. The experim ental m ethod constitutes a decisive factor in th e fight against scholastic au th o rity and m ystification. Physics opposes experim ental facts to th e concealed properties (qualitates occultae) of scholasticism. A n y a b s o l u t i s a t i o n o r o v e r e s t i m a t i o n o f t h e e x p e r i m e n t a l m e t h o d i s t h e f i r s t h i s t o r i c a l a n d e p i s t e m o l o g i c a l s o u r c e of positivism related to physics. This is the source of th e establishm ent of th e phenom enological stan d point.
A t th e tim e w hen physics became independent, it was in search for m aterials, thus experim entation has been the most im po rtant problem ; this has been the new m ethod of research; how ever even a t this epoch physics was not characterized b y m ere “phenom enology”. Namely, the m athem atical form ulation of experim ental resu lts m eans alread y to go beyond experim ental results.
In various periods of the h isto ry of physics th e task of experim en tatio n or th a t of theoretical sum m arizing m ay come into prominence,
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experim entating, however, and establishing a theory (phénoménologie description and model) do not diverge, not even in certain tran sito ry periods.
It was th e logic of fight against scholasticism which led to N ew ton’s
hypotheses non fingo, w hich had not been recognized by N ew ton him
self bu t directly led to th e one-sided em piricism of th e Newtonians of the 18th century, indicating th e strengthening of phenomenological con cept.
It m ay be revealed by m eans of a m ore detailed historical study, th a t even th is period, th e 18th century, w as not a phenomenological one inf th e sense of th e w ord used by the phenomenologists. W eightless m aterials and action at distance are certainly not m ere descriptions of experim ental results, b u t th e ir p articu lar explanations, and models for th e ir interpretation. These models reflect beyond doubt th e phenomeno logical conception, since th ey req u ire special kinds of m aterial for every group of phenom ena, attain ab le a t th a t tim e b y w ay of experim ent. This m etaphysical conception, im perative in the situation of history of science in th e 18th century, brought about idealistic tendencies over straining its own range (action a t distance is an effect w ithout m aterial). The m ultiplication of experim ental resu lts exceeded th e m ethaphysi- cal conception; the phenomenological consideration w as overshadowed by th e success of mechanical model form ation. From th e middle of th e 19th cen tu ry physical research was possessed by the idea of the u n i versal connection of phenom ena, considering, however, mechanics as a basis of connections. (It is an in teresting fact of th e history of science th a t although dialectical and historical m aterialism w ere established in th e m iddle of the 19th century, physics developed up to th e end of the 19th century on the platform of m echanical m aterialism ). Physics of the 19th cen tu ry m et w ith success in th e domain of mechanical model form ation even in such fields w here discoveries objectively pointed already beyond the range of mechanical effects (optics, electricity, etc.).
T h e n e x t s t a g e o f t h e h i s t o r y o f p h y s i c s w h e r e p h e n o m e n o l o g i c a l t e n d e n c i e s w e r e p r e v a i l i n g a g a i n , was the tu rn of the 20th century. W hen physics became in dependent, th e necessity to overcome scholastic dogma, led to biassed apology of phenomenology. At the tu rn of the 20th century, however, it was been t h e b r e a k - t h r o u g h o f t h e a l m o s t d o g m a t i c s y s t e m o f c l a s s i c a l p h y s i c s which led to the same result.
In the years of th e tu rn of th e 20-th century it was discovered th a t th e models of classical physics, constructed and highly respected in the 19th century, are not absolute at all. This led to the negation of models in general, and fu rth er, not only to th e negation of models, bu t also to th e negation of the objective existence of th e world. The trend,
P henom en ology and M odel C on stru ction 1 0 9
standing against model form ation, relying only on phenom enology at the tu rn of the century, produced an almost subjective idealistic te n dency, i.e. Machism. E xperim ental facts at th e tu rn of the century, breaking through the generalizing level of classical physics, inspired the establishm ent of new theories. The theory of relativ ity , and p a rti cularly the quantum theory, signify a decisive break w ith classical physics. The quantum theory arises as a m athem atical generalization (Schrödinger, Heisenberg) of ad hoc prem ises (quanta — Planck, Ein stein, Bohr) and of hazardous analogies (de Broglie). The way, leading from B ohr’s successful, though incom prehensible quantum -conditions to th e m ore successful, bu t still less com prehensible operator and m atrix-calculus, stipulates a continuous experim ental control of the m athem atical ap paratu s of great efficacy, b u t of uncleared physical content.
In this period of th e h isto ry of physics — not a t last on the in flu ence of M achism — phenom enology prevails m ore th an ever before. It becomes alm ost a m otto of physical research th a t “there exists only w hat is m easurable”. This proposition, however, seems to be rig h t only a t first sight. If it is in terp rete d consistently, it leads to com plete negation of form ing hypotheses. H ypothetic models m ay not be form ed, since if som ething is not m easurable, it m ay not be assum ed th a t it exists.
c) The way, leading to the developm ent of the q uantum theory, was not free at all from model construction (considering Planck, or the classical quantum theory of Bohr or also de B roglie’s wave th eo ry of m atter), model building came nevertheless into th e limbo of classical physics as obsolete inheritance, — according to public opinion.
Speaking m ore exactly, this phenom enological trend, — at presen t already as a neopositivist trend, — disapproves only of m a t e r i a l models, b u t not of m athem atical ones, although for phenom enology even m athem atical models rep resent a transcensus, a penetratio n behind sensory experiences as m athem atical models do, and thus even m ath e m atical models should be inadmissible. The adm ission of m athem atical models m ust necessarily lead, beside the negation of m aterial models, to an epistem ologically false concept of m athem atics. It m ust lead t*o an objective idealism of such type, w hich considers m athem atical ap paratus, m athem atics itself as th e final essence of the world. The logic of h isto ry has brought about this concept. C ertain problem s of d iv er gence of the quantum theory, as w ell as the accum ulated new m aterial of facts (several tim es ten elem entary particles and th eir m u tu al tra n s form ations into the another) urged on the establishm ent of a new syn thesis. This new synthesis has not y et taken place. B ut th e m athem a tical app aratus of research, striving after this theoretical level has been conceived by m any authors (beeing still under th e phenom enological
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influence one or two decades ago) in an objective idealistic m anner, m entioned already. To m ention only th e most em inent one: Heisenberg considers his m aterial equation as a proof of th e Platonic philosophy. Also objective idealistic in terp retatio n s relating to recent progress of developm ent of physics are based upon the problem of the relation betw een phenom enology and model form ation, w hich is epistemologi- cally not p ro perly cleared.
Sum m arizing: The phenom enological concept came about w hen physics w ere becoming independent in m odern times, in connection w ith the developm ent of experim ental m ethods at th e height of the fight against scholasticism; it w as flam ed up again w ith a new effort in th e tu rn of th e 20th cen tu ry at the b irth of m odern physics, in course of polemics against classical physics. In th e first period th e phénom éno logie “oversw inging” of th e fight against scholasticism led to a restric ted em piricism as w ell as to an idealistic model form ation (action w ith out m aterial) in th e course of th e 18th century. In th e tu rn of the 19th and 20th centuries polemics against m echanical models of classical physics from th e general negation of model form ation to a subjective idealistic negation of objective reality. The lack of elucidation of th e relation betw een m athem atical and m aterial models in th e last decades emphasized the objective idealistic in terp retatio n of physical laws. The new level of generalization overpassing classical physics, — about half a century ago — w as established in such a social and ideological situation in th e h isto ry of physics, th a t it was combined w ith subjective idealistic tendencies already since its b irth . Today th ere exists already a social and ideological, as w ell as a physical and historical possibility for th e latest physical level of generalization not to be charged w ith negative ideological ballasts. In this respect, th e lessons draw n from th e h isto ry of science could play an im p o rtan t role indeed.
