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Perspectives in biology and medicine

The Physicist's Conception of Nature by Werner Heisenberg (review)

George Gamow

Published Sep 1, 1959• 0 citations
Publisher

Abstract

is all about, and not bothering to familiarize themselves in specific detail with the vast accumulation of behavioral data upon which the conclusions ofpsychoanalysis are based. Though specialists in scientific method, they refuse to look through Galileo's telescope [p. 349]. Hospers examines with skill and calmness many of die totally illogical arguments used in this conference, permitting one to end the volume with a faintly restored faith that one day there will be "a free, critical interchange ofviews on die scientific status of psychoanalysis" between philosophers ofscience and psychoanalysts. Ifthere is any lesson to be drawn from this kind ofexhibition, it is that diere is no substitute for firsthand knowledge ofthe method and data ofa discipline as a prerequisite for any critical discussion ofits merit and validity. This may seem like an utterly banal dictum, yet the facts are that it is too often casually disregarded when it comes to the sciences ofhuman behavior. Any taxicab driver will freely volunteer opinions about reasons forjuvenile delinquency, sexual perversions, drug addiction, or dreams—but rarely about astral physics, genetics, or C14 dating. There is a good reason for this; all such matters touch one personally to varying degrees. But the philosopher (and, even more importandy, the physician) must be cautious not to confuse this personal interest and ¦ involvement with the scientific knowledge and detachment necessary for critical judgment . The latter come about only through long experience and diligent study. George L. Engel University ofRochester The Physicist's Conception ofNature. ByWerner Heisenberg.Translated from the German by ArnoldJ. Pomerans. New York: Harcourt, Brace & Co., 1958. Pp. 192. $3.75. This book, written by a famous German scientist, the founder ofquantum mechanics, die discoverer of die uncertainty relations, and die Nobel prize winner in physics for 1933, does not do much credit to die author. The first 67 pages comprise three chapters which apparendy represent an attempt to amalgamate the three speechesdelivered or three articles written on three different occasions at diree different times. It is difficult to date die first two chapters, but die diird one must have been written in 1948, since in it the author refers to a conversation which he had had "some diirty years ago" during die Communist revolt in Munich (1918). The first chapter of the book presents die idea of the three stages of die evolution ofhuman diought about the surrounding world. According to die author, during olden times (ofKepler, etc.) scientists saw die world as die work ofGod. During the nineteendi century die world was existing all for itself, independent ofman. Since the discovery of the uncertainty relations, die man looking at the surrounding world sees his own image in it. The second chapter represents a discussion ofuncertainty relations and contains several interesting ideas (for example, about past and future difference in die case ofvery short time intervals) which may be ofgreat interest to a person trained in die modern quantum theory but will pass unnoticed by a general reader. 158 Book Reviews Perspectives in Biology and Medicine · Autumn 1939 The third chapter discusses die relative advantages ofclassical (i.e., Greek grammar, etc.) and scientific education and presents arguments in favor ofdie former: "Thus, we may say in favour ofclassical education diat it is always a good diing to know the roots, even ifthey may not always be of practical use" (p. 52). However, by die end of the chapter (p. 67) die audior comes to die conclusion: "It does not matter whedier we prefer a classical or a scientific education. What alone matters is our unshakable faidi in the West." The remaining 115 pages ofthe text contain a masterful selection ofquotations from Kepler, Galileo, Newton, Oswald, De Broglie, and others which are supposed to illustrate die ideas ofdie author expressed in die first 67 pages. G. GAMOW University ofColorado The Autobiography of Charles Darwin, 1809-1882. Edited, with Appendix and notes, by his granddaughter Nora Barlow. New York: Harcourt, Brace & Co., 1959. Pp. 253. $4.50. Darwin's autobiography was written mainly in 1876, six years before his death, with additional material inserted during his last yean. When first published in 1887, as part ofthe Life and Letters ofCharles Darwin, edited by his son Francis, it...

DOI
10.1353/pbm.1959.0047

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is all about, and not bothering to familiarize themselves in specific detail with the vast accumulation of behavioral data upon which the conclusions ofpsychoanalysis are based. Though specialists in scientific method, they refuse to look through Galileo's telescope [p. 349]. Hospers examines with skill and calmness many of die totally illogical arguments used in this conference, permitting one to end the volume with a faintly restored faith that one day there will be "a free, critical interchange ofviews on die scientific status of psychoanalysis" between philosophers ofscience and psychoanalysts. Ifthere is any lesson to be drawn from this kind ofexhibition, it is that diere is no substitute for firsthand knowledge ofthe method and data ofa discipline as a prerequisite for any critical discussion ofits merit and validity. This may seem like an utterly banal dictum, yet the facts are that it is too often casually disregarded when it comes to the sciences ofhuman behavior. Any taxicab driver will freely volunteer opinions about reasons forjuvenile delinquency, sexual perversions, drug addiction, or dreams—but rarely about astral physics, genetics, or C14 dating. There is a good reason for this; all such matters touch one personally to varying degrees. But the philosopher (and, even more importandy, the physician) must be cautious not to confuse this personal interest and ¦ involvement with the scientific knowledge and detachment necessary for critical judgment . The latter come about only through long experience and diligent study. George L. Engel University ofRochester The Physicist's Conception ofNature. ByWerner Heisenberg.Translated from the German by ArnoldJ. Pomerans. New York: Harcourt, Brace & Co., 1958. Pp. 192. 3.75. This book, written by a famous German scientist, the founder ofquantum mechanics, die discoverer of die uncertainty relations, and die Nobel prize winner in physics for 1933, does not do much credit to die author. The first 67 pages comprise three chapters which apparendy represent an attempt to amalgamate the three speechesdelivered or three articles written on three different occasions at diree different times. It is difficult to date die first two chapters, but die diird one must have been written in 1948, since in it the author refers to a conversation which he had had "some diirty years ago" during die Communist revolt in Munich (1918). The first chapter of the book presents die idea of the three stages of die evolution ofhuman diought about the surrounding world. According to die author, during olden times (ofKepler, etc.) scientists saw die world as die work ofGod. During the nineteendi century die world was existing all for itself, independent ofman. Since the discovery of the uncertainty relations, die man looking at the surrounding world sees his own image in it. The second chapter represents a discussion ofuncertainty relations and contains several interesting ideas (for example, about past and future difference in die case ofvery short time intervals) which may be ofgreat interest to a person trained in die modern quantum theory but will pass unnoticed by a general reader. 158 Book Reviews Perspectives in Biology and Medicine · Autumn 1939 The third chapter discusses die relative advantages ofclassical (i.e., Greek grammar, etc.) and scientific education and presents arguments in favor ofdie former: "Thus, we may say in favour ofclassical education diat it is always a good diing to know the roots, even ifthey may not always be of practical use" (p. 52). However, by die end of the chapter (p. 67) die audior comes to die conclusion: "It does not matter whedier we prefer a classical or a scientific education. What alone matters is our unshakable faidi in the West." The remaining 115 pages ofthe text contain a masterful selection ofquotations from Kepler, Galileo, Newton, Oswald, De Broglie, and others which are supposed to illustrate die ideas ofdie author expressed in die first 67 pages. G. GAMOW University ofColorado The Autobiography of Charles Darwin, 1809-1882. Edited, with Appendix and notes, by his granddaughter Nora Barlow. New York: Harcourt, Brace & Co., 1959. Pp. 253. 4.50. Darwin's autobiography was written mainly in 1876, six years before his death, with additional material inserted during his last yean. When first published in 1887, as part ofthe Life and Letters ofCharles Darwin, edited by his son Francis, it...
THE conceptual problems raised by the discovery of quantum effects have not been fully resolved after half a century. Part of the reason for this is undoubtedly to be found in the mutual ignorance which prevails between physicists and philosophers. In his book Heisenberg brings together a philosophically inclined temperament with an unrivalled knowledge of physics. The result is a book of very great interest, however much one might disagree with his conclusions. The collection of essays of which the other book is made up is intended to bring crucial conceptual problems in physics especially to the notice of philosophers. The design and intention of the collection is admirable for this is the proper way to overcome the departmentalization of interest that has left the deep conceptual problems still unresolved. Men like Heisenberg who combine philosophical temperament with scientic knowledge of great distinction are rare, and yet the difficulties can only be cleared up by the application of philosophical techniques of analysis to problems which are an intimate and difficult part of physics. A great deal of the interest of Heisenberg's book lies in the very comprehensive account he gives of the origin and growth of the Copenhagen school, and the way the new phenomena forced a largely unwelcome picture of nature upon Bohr and his friends. The most important chapter from a philosophical point of view is that in which Heisenberg defends this interpretation against the attacks to which it has been subjected. The essence of his argument for the interpretation can be summed up in two propositions. (i) The Copenhagen interpretation of physical theory, which depends upon the acceptance of the so-called Principle of Complementarity, is an inevitable and final interpretation. The reason for this is that there are only two possible general models for understanding given physical phenomena; a particle model or a wave model. These are exhaustive and exclusive because the former depends upon discontinuous and the latter upon continuous (using substance here in the traditional philosophical sense). If we find, as we do, that the two fundamental constituents of the universe, matter and radiation, each exhibit two classes of phenomena, one explainable only on a particle model and one on a wave model, then we are compelled to adopt a complementarity hypothesis and give up the idea of finding a single and uniform model for the understanding of phenomena. There are only two kinds of models; they are mutually exclusive; both are required; hence we either despair before an insoluble problem or adopt the Copenhagen interpretation. (2) Any serious criticism of this interpretation must offer an alternative
BOOK REVIEWS 425 sense is concerned, mathematical logic distorts and hides the nature and role of the proper method or organon of philosophical knowledge; and, with its technical formal symbolism, simply obstructs the language of such reasoning. No important point in logic itself, or in any branch of philosophy , is illumined simply by being formulated in the symbolism of mathematical logic. And the major part of logic, logic considered on the part of matter, is necessarily a closed book to the formalism of mathematical logic. Philosophy and mathematical logic are not really made for each other; incompatibility would necessarily follow from their marriage. But it is quite otherwise with respect to the role mathematical logic plays in experimental science. It is the appropriate tool experimental science needs for its investigation of the quantitative and relational aspects of things. It is the calculus needed for the dialectical exploration of the experimental scientist. It is as such a calculus that mathematical logic really works and where its fruitful application is realized. Divorced from the role it plays for experimental science, mathematical logic seems to become merely a game of arbitrarily constructed systems of purely formal rules of procedure within the web of mathematical imagination. Such a formulation of what the excellence of mathematical logic consists in (as well as what it does not consist in) is certainly open to further investigation and consideration. In any case, it seems to me that both traditional and mathematical logicians would benefit seeing the proper excellence of each rather than trying to have one simply obliterated by the other. Of one thing, nevertheless, I am certain: serious traditional and mathematical logicians should read Professor Veatch's book for a thorough, conscientious, and able discussion of the relation and contrast between traditional and mathematical logic. It is a necessary step in achieving a balanced judgment and evaluation of both, the indispensable prerequisite for any fruitful discussion. JoHN A. OEsTERLE College of St. Thomas St. Paul, Minnesota Philosophic Problems of Nuclear Science. By WERNER HEISENBERG. Translated by F. C. Hayes. New York: Pantheon Books, 19M~. Pp. HW. $!il.75. This little volume contains eight lectures which were delivered at different places and times between the years 1934 and 1948. The message which it contains is noteworthy both because of the great authority of the author in the field of theoretical physics and because it is full, frank and informative statement of the historic aims of mathematical physics and a critical account of the present achievement of this science. 426 BOOK REVIEWS Although the so-called classical physics originated chiefly from the work of Galileo and Newton in the seventeenth century, the author of these lectures sees the whole development of modern physics as an effort to solve the problem first posed by the ancient Greek philosophers who asked: what are all things made of? Pythagoras was first to realize the mathematical order in musical notes, and Democritus said that all things are made of atoms. These are the terms of the historic problem and of its solution through mathematical physics. The ancient physicists were seeking a single material principle by which everything might be explained and understood in the clear light of mathematical formulation. Modern science has accepted from antiquity the idea of a pattern in the world which is capable of mathematical description . But we must not think that pure theoretical understanding is the only goal. Such an understanding is humanly unsatisfying, and seeks an outlet in technical applications. The mathematical formulation is itself an abstract control of things, and it enables man to make nature serve his own purposes. Furthermore, it gives a real insight into the interrelations of things, and will help man to appreciate his appropriate position in nature. Here in two words, understanding and control, we have the aims of this type of science. The understanding must be crystal clear, that is, mathematical in form. It must be a universal understanding, attaining to the principle of all things and revealing the real interrelations of things and man's position in the universe. Control also must in a sense be universal , that is, sufficient to enable man to make nature serve his own purpose...
Twentieth-Century Physics A century which has run less than a third of its course has already witnessed two great upheavals in physical science. These are associated with the words Relativity and Quanta, and have forced the physicist of to-day to view nature against a background of ideas which is very different from that of his nineteenth-century predecessor. The latter thought of nature as an assemblage of objects located in space and continually changing with the passage of time. It was something entirely detached from, and external to, himself; something which he could study and explore from a distance as the astronomer studies the surface of the sun through his telescope, or the explorer the desert from his aeroplane. He thought of the apparatus of his laboratory as the astronomer thinks of his telescope, or the explorer of his field-glass; it shewed him things which were there whether he looked at them or not, which had been there before the first man appeared on earth, and would still be there after the last man had been frozen to extinction. Finally he accepted a “common-sense” view of nature, believing that there was no great difference between appearance and reality; the possibility that things were not as they seemed might provide an admirable subject for a debating society of philosophers, but was of as little practical concern to the scientist as to the farm-labourer. Although he may not have realised it, this complex of beliefs constituted a philosophical creed in itself.
The new physics just described was still based largely on Newtonian ideas. Indeed, in its theoretical aspects, it might not unfairly be described as a final attempt to explain the world in materialistic terms—as particles being pushed and pulled about in space and time. Nevertheless, the new physics had found it necessary to abolish most of the forces of pushing and pulling, replacing the gradual changes of motion of the particles under these forces by sudden and unpredictable jumps. These appeared to involve violations of the law of causality, both in the disintegration of radioactive atoms and also in the internal changes of ordinary atoms. We seemed to see Fate defying this law as she picked out certain atoms for disintegration or collapse and, by her apparently capricious acts, sent the universe along one path or another according to her whim. On such lines the new physics had explained many phenomena which had hitherto seemed inexplicable, but it had by no means met with complete success. For instance, while it gave a perfect interpretation of the simplest spectrum of all, namely that of the hydrogen atom, it failed with more complex spectra. This was not necessarily a fatal objection; a few emendations and possibly a few new ad hoc assumptions might have effected a complete reconciliation, although this seems improbable.
In a recent number of Blackfriars (July, 1949) Dr A. W. Gledhill has discussed very competently some aspects of the statistical method as used in modern physics. He has tried to show there ‘that modern physical theory does not contradict the principle of causality’. Having made a study of this subject over quite a number of years, the writer, while agreeing with some of Dr Gledhill’s conclusions, feels nevertheless that there are a few points which have not been covered as adequately as the importance of the subject for modern philosophy seems to warrant. In order to understand the controversy about the validity or non-validity of the principle of causality, which has been initiated by Heisenberg’s uncertainty principle, it is necessary to realise, first of all, that when a physicist speaks about causality, he usually does not mean the same thing as a scholastic philosopher. In scholastic philosophy one distinguishes different kinds of causes, such as the material, the efficient, the final, as well as the formal and exemplary causes. The classical physicist, on the other hand, since the time of Galileo, admits only efficient causes. Let us therefore give a brief sketch of the development of this concept of scientific causality and show the reasons for this limitation. The purpose of a scientific theory is the prediction of events among the natural objects which form the field of enquiry of the particular science concerned. Evidently, the more certain the prediction, the better the theory on which it is based.
For many years the physical interpretation of quantum theory has been dominated by the “wave-particle duality” attitude of the “Copenhagen school.” This point of view is eloquently described in Bohr's collection of essays on the subject. Despite persistent concerns with apparent paradoxes and limitations to this interpretation (as exemplified by Schrodinger's cat, the paradox of Einstein, Podolsky and Rosen, among others), the Copenhagen view persists de facto in the daily life of the modern physicist. Traditional quantum theory has so successfully explained such a vast amount of data in atomic and molecular physics, solid state physics (and to a lesser extent, elementary particle physics) that little doubt can exist concerning its essential validity. As a consequence of the overwhelming practical success of the “Copenhagen interpretation, ” the latter has acquired the status of dogma. For many years, therefore, most physicists have found it expedient to relegate the puzzling aspects of the theory to philosophers, and mathematicians. Nevertheless, a persistent interest in this subject has produced a significant and fascinating literature, reviewed by Jammer. In recent years, concerns over the proper meaning to be ascribed to quantum theory have produced an increasingly deep and incisive series of investigations. These investigations fall generally into two categories: either (1) discussion of the philosophical content of the theory, or (2) analyses of the mathematical variants of the theory and their connection with differing interpretational schemes. Physicists tend to be detached from a commitment to philosophical issues, because of their realization of the transient character of the meanings attached to theories of the day. As a simple illustration of this we can mention the profound differences between nonrelativistic and relativistic quantum mechanics.