We have seen that the question of the epistemological deductions that can be drawn from the new physics has been raised and is being discussed from the most varied points of view in English, German and French literature. There can be no doubt that we have before us a certain international ideological current, which is not dependent upon any one philosophical system, but which is the result of certain general causes Iying outside the sphere of philosophy. The foregoing review of the facts undoubtedly shows that Machism is “connected” with the new physics, but at the same time reveals that the version of this connection spread by our Machians is fundamentally incorrect. As in philosophy, so in physics, our Machians slavishly follow the fashion, and are unable from their own, Marxist, standpoint to give a general survey of particular currents and to judge the place they occupy.
A double falsity pervades all the talk about Mach’s philosophy being “the philosophy of twentieth-century natural science,” “the recent philosophy of the sciences,” “recent natural-scientific positivism” and so forth. (Bogdanov in the introduction to Analysis of Sensations, pp. iv, xii; cf. also Yushkevich, Valentinov and Co.) Firstly, Machism is ideologically connected with only one school in one branch of modern science. Secondly, and this is the main point, what in Machism is connected with this school is not what distinguishes it from all other trends and systems of idealist philosophy, but what it has in common with philosophical idealism in general. It suffices to cast a glance at the ideological current in question as a whole in order to leave no shadow of doubt as to the truth of this statement. Take the physicists of this school: the German Mach, the Frenchman Henri Poincaré, the Belgian P. Duhem, the Englishman Karl Pearson. They have much in common: they have the same basis and are following the same direction, as each of them rightly acknowledges. But what they have in common includes neither the doctrine of empirio-criticism in general, nor Mach’s doctrine, say, of the “world-elements” in particular. The three latter physicists even know nothing of either of these doctrines. They have “only” one thing in common—philosophical idealism, towards which they all, without exception, tend more or less consciously, more or less decisively. Take the philosophers who base themselves on this school of the new physics, who try to ground it epistemologically and to develop it, and you will again find the German immanentists, the disciples of Mach, the French neo-criticists and idealists, the English spiritualists, the Russian Lopatin and, in addition, the one and only empirio-monist, A. Bogdanov. They all have only one thing in common, namely, that they all—more or less consciously, more or less decisively, either with an abrupt and precipitate slant towards fideism, or with a personal aversion to it (as in Bogdanov’s case)—are vehicles of philosophical idealism.
The fundamental idea of the school of the new physics under discussion is the denial of the objective reality given us in our sensation and reflected in our theories, of the doubt as to the existence of such a reality. Here this school departs from materialism (inaccurately called realism, neo-mechanism, hylo-kinetism, and not in any appreciable degree consciously developed by the physicists), which by general acknowledgment prevails among the physicists—and departs from it as a school of “physical” idealism.
To explain this last term, which sounds very strange, it is necessary to recall an episode in the history of modern philosophy and modern science. In 1866 L. Feuerbach attacked Johannes Müller, the famous founder of modern physiology, and ranked him with the “physiological idealists” (Werke, Vol. X, p. 197). The idealism of this physiologist consisted in the fact that when investigating the significance of the mechanism of our sense-organs in relation to sensations, showing, for instance, that the sensation of light is produced as the result of the action of various stimuli on the eye, he was inclined to arrive from this at a denial that our sensations are images of objective reality. This tendency of one school of scientists towards “physiological idealism,” i.e., towards an idealist interpretation of certain data of physiology, was very accurately discerned by L. Feuerbach. The “connection” between physiology and philosophical idealism, chiefly of the Kantian kind, was for a long time after that exploited by reactionary philosophy. F. A. Lange made great play of physiology in support of Kantian idealism and in refutation of materialism; while among the immanentists (whom Bogdanov so incorrectly places midway between Mach and Kant), J. Rehmke in 1882 specially campaigned against the allegation that Kantianism was con firmed by physiology. That a number of eminent physiologists at that time gravitated towards idealism and Kantianism is as indisputable as that today a number of eminent physicists gravitate towards philosophical idealism. “Physical” idealism, i.e., the idealism of a certain school of physicists at the end of the nineteenth century and the beginning of the twentieth century, no more “refutes” materialism, no more establishes the connection between idealism (or empirio-criticism) and natural science, than did the similar efforts of F. A. Lange and the “physiological” idealists. The deviation towards reactionary philosophy manifested in both cases by one school of scientists in one branch of science is a temporary deflection, a transitory period of sickness in the history of science, an ailment of growth, mainly brought on by the abrupt breakdown of old established concepts.
The connection between modern “physical” idealism and the crisis of modern physics is, as we have already pointed out, generally acknowledged. “The arguments of sceptical criticism levelled against modern physics"—writes A. Rey, who is referring not so much to the sceptics as to the outspoken adherents of fideism, like Brunetiere—"essentially amount to the proverbial argument of all sceptics: a diversity of opinions” (among the physicists). But this diversity “proves nothing against the objectivity of physics.” “In the history of physics, as in history generally, one can distinguish great periods which differ by the form and general aspect of theories. . . . But as soon as a discovery is made that affects all fields of physics because it establishes some cardinal fact hitherto badly or very partially perceived, the entire aspect of physics is modified; a new period sets in. This is what occurred after Newton’s discoveries, and after the discoveries of Joule-Mayer and Carnot-Clausius. The same thing, apparently, is taking place since the discovery of radioactivity. . . . The historian who later sees things from the necessary distance has no trouble in discerning a steady evolution where contemporaries saw conflicts, contradictions, and divisions into various schools. Apparently, the crisis which physics has undergone in recent years (despite the conclusions drawn from it by philosophical criticism) is no different. It even excellently illustrates the typical crisis of growth (crise de croissance) occasioned by the great modern discoveries. The undeniable transformation of physics which will result (could there be evolution or progress without it?) will not perceptibly alter the scientific spirit” (op. cit., pp. 370-72).
Rey the conciliator tries to unite all schools of modern physics against fideisml This is a falsity, well meant, but a falsity nevertheless; for the trend of the school of Mach-Poincaré-Pearson towards idealism (i.e., refined fideism) is beyond dispute. And the objectivity of physics that is associated with the basis of the “scientific spirit,” as distinct from the fideist spirit, and that Rey defends so ardently, is nothing but a “shamefaced” formulation of materialism. The basic materialist spirit of physics, as of all modern science, will overcome all crises, but only by the indispensable replacement of metaphysical materialism by dialectical materialism.
Rey the conciliator very often tries to gloss over the fact that the crisis in modern physics consists in the latter’s deviation from a direct, resolute and irrevocable recognition of the objective value of its theories. But facts are stronger than all attempts at reconciliation. The mathematicians, writes Rey, “in dealing with a science, the subject matter of which, apparently at least, is created by the mind of the scientist, and in which, at any rate, concrete phenomena are not involved in the investigation, have formed too abstract a conception of the science of physics. Attempts have been made to bring it ever closer to mathematics, and the general conception of mathematics has been transferred to the conception of physics. . . . This is an invasion of the mathematical spirit into the methods of judging and understanding physics that is denounced by all the experimenters. And is it not to this influence, none the less powerful because at times concealed, that are often due the uncertainty, the wavering of mind regarding the objectivity of physics, and the detours made or the obstacles surmounted in order to demonstrate it? . . .” (p. 227).
This is excellently said. “Wavering of mind” as to the objectivity of physics—this is the very essence of fashionable “physical” idealism.
“. . . The abstract fictions of mathematics seem to have interposed a screen between physical reality and the manner in which the mathematicians understand the science of this reality. They vaguely feel the objectivity of physics. . . . Although they desire above all to be objective when they engage in physics; although they seek to find and retain a foothold in reality, they are still haunted by old habits. So that even in the concepts of energetics, which had to be built more solidly and with fewer hypotheses than the old mechanism—which sought to copy (décalquer) the sensible universe and not to reconstruct it—we are still dealing with the theories of the mathematicians. . . . They [the mathematicians] have done everything to save objectivity, for they are aware that without objectivity there can be no physics. . . . But the complexity or deviousness of their theories nevertheless leaves an uneasy feeling. It is too artificial, too far-fetched, too stilted (édifié); the experimenter here does not feel the spontaneous confidence which constant contact with physical reality gives him. . . . This in effect is what is said by all physicists who are primarily physicists or who are exclusively physicists—and their name is legion; this is what is said by the entire neo-mechanist school. . . . The crisis in physics lies in the conquest of the realm of physics by the mathematical spirit. The progress of physics on the one hand, and the progress of mathematics on the other, led in the nineteenth century to a close amalgamation between these two sciences. . . . Theoretical physics has become mathematical physics. . . . Then there began the formal period, that is to say, the period of mathematical physics, purely mathematical; mathematical physics not as a branch of physics so to speak, but as a branch of mathematics cultivated by the mathematicians. Along this new line the mathematician, accustomed to conceptual (purely logical) elements, which furnish the sole subject matter of his work, and feeling himself cramped by crude, material elements, which he found insufficiently pliable, necessarily always tended to reduce them to abstractions as far as possible, to present them in an entirely non-material and conceptual manner, or even to ignore them altogether. The elements, as real, objective data, as physical elements, so to speak, completely disappeared. There remained only formal relations represented by the differential equations. . . . If the mathematician is not the dupe of his constructive work, when he analyses theoretical physics . . . he can recover its ties with experience and its objective value, but at a first glance, and to the uninitiated person, we seem faced with an arbitrary development. . . . The concept, the notion, has everywhere replaced the real element. . . . Thus, historically, by virtue of the mathematical form assumed by theoretical physics, is explained . . . the ailment (le malaise), the crisis of physics, and its apparent withdrawal from objective facts” (pp. 228-32).
Such is the first cause of “physical” idealism. The reactionary attempts are engendered by the very progress of science. The great successes achieved by natural science, the approach to elements of matter so homogeneous and simple that their laws of motion can be treated mathematically, encouraged the mathematicians to overlook matter. “Matter disappears,” only equations remain. In the new stage of development and apparently in a new manner, we get the old Kantian idea: reason prescribes laws to nature. Hermann Cohen, who, as we have seen, rejoices over the idealist spirit of the new physics, goes so far as to advocate the introduction of higher mathematics in the schools—in order to imbue high-school students with the spirit of idealism, which is being extinguished in our materialistic age (F. A. Lange, Geschichte des Materialismus, 5. Auflage, 1896, Bd. II, S. xlix). This, of course, is the ridiculous dream of a reactionary and, in fact, there is and can be nothing here but a temporary infatuation with idealism on the part of a small number of specialists. But what is highly characteristic is the way the drowning man clutches at a straw, the subtle means whereby representatives of the educated bourgeoisie artificially attempt to preserve, or to find a place for, the fideism which is engendered among the masses of the people by their ignorance and their downtrodden condition, and by the wild absurdities of capitalist contradictions.
Another cause which bred “physical” idealism is the principle of relativism, the relativity of our knowledge, a principle which, in a period of breakdown of the old theories, is taking a firm hold upon the physicists, and which, if the latter are ignorant of dialectics, is bound to lead to idealism.
The question of the relation between relativism and dialectics plays perhaps the most important part in explaining the theoretical misadventures of Machism. Take Rey, for instance, who like all European positivists has no conception whatever of Marxist dialectics. He employs the word dialectics exclusively in the sense of idealist philosophical speculation. As a result, although he feels that the new physics has gone astray on the question of relativism, he nevertheless flounders helplessly and attempts to differentiate between moderate and immoderate relativism. Of course, “immoderate relativism logically, if not in practice, borders on actual scepticism” (p. 215), but there is no “immoderate” relativism, you see, in Poincaré. Just fancy, one can, like an apothecary, weigh out a little more or a little less relativism and thus save Machism!
As a matter of fact, the only theoretically correct formulation of the question of relativism is given in the dialectical materialism of Marx and Engels, and ignorance of it is bound to lead from relativism to philosophical idealism. Incidentally, the failure to understand this fact is enough to render Mr. Berman’s absurd book, Dialectics in the Light of the Modern Theory of Knowledge, utterly valueless. Mr. Berman repeats the old, old nonsense about dialectics, which he has entirely failed to understand. We have already seen that in the theory of knowledge all the Machians, at every step, reveal a similar lack of understanding.
All the old truths of physics, including those which were regarded as firmly established and incontestable, have proven to be relative truths—hence, there can be no objective truth independent of mankind. Such is the argument not only of all the Machians, but of the “physical” idealists in general. That absolute truth results from the sum-total of relative truths in the course of their development; that relative truths represent relatively faithful reflections of an object existing independently of man; that these reflections become more and more faithful; that every scientific truth, notwithstanding its relative nature, contains an element of absolute truth—all these propositions, which are obvious to anyone who has thought over Engels’ Anti-Dühring, are for the “modern” theory of knowledge a book with seven seals.
Such works as Duhem’s Theory of Physics, or Stallo’s, which Mach particularly recommends, show very clearly that these “physical” idealists attach the most significance to the proof of the relativity of our knowledge, and that they are in reality vacillating between idealism and dialectical materialism. Both authors, who belong to different periods, and who approach the question from different angles (Duhem’s speciality is physics, in which field he has worked for twenty years; Stallo was an erstwhile orthodox Hegelian who grew ashamed of his own book on natural philosophy, written in 1848 in the old Hegelian spirit), energetically combat the atomistic-mechanical conception of nature. They point to the narrowness of this conception, to the impossibility of accepting it as the limit of our knowledge, to the petrification of many of the ideas of writers who hold this conception. And it is indeed undeniable that the old materialism did suffer from such a defect; Engels reproached the earlier materialists for their failure to appreciate the relativity of all scientific theories, for their ignorance of dialectics and for their exaggeration of the mechanical point of view. But Engels (unlike Stallo) was able to discard Hegelian idealism and to grasp the great and true kernel of Hegelian dialectics. Engels rejected the old metaphysical materialism for dialectical materialism, and not for relativism that sinks into subjectivism. “The mechanical theory,” says Stallo, for instance, “in common with all metaphysical theories, hypostases partial, ideal, and, it may be, purely conventional groups of attributes, or single attributes, and treats them as varieties of objective reality” (p. 150). This is quite true, if you do not deny objective reality and combat metaphysics for being anti-dialectical. Stallo does not realise this clearly. He has not understood materialist dialectics and therefore frequently slips, by way of relativism, into subjectivism and idealism.
The same is true of Duhem. With an enormous expenditure of labour, and with the help of a number of interesting and valuable examples from the history of physics, such as one frequently encounters in Mach, he shows that “every law of physics is provisional and relative, because it is approximate” (p. 280). The man is hammering at an open door!—will be the thought of the Marxist when he reads the lengthy disquisitions on this subject. But that is just the trouble with Duhem, Stallo, Mach and Poincaré, that they do not perceive the door opened by dialectical materialism. Being unable to give a correct formulation of relativism, they slide from the latter into idealism. “A law of physics, properly speaking, is neither true nor false, but approximate"—writes Duhem (p. 274). And this “but” contains the beginning of the falsity, the beginning of the obliteration of the boundary between a scientific theory that approximately reflects the object, i.e., approaches objective truth, and an arbitrary, fantastic, or purely conventional theory, such as, for example, a religious theory or the theory of the game of chess.
Duhem carries this falsity to the point of declaring that the question whether “material reality” corresponds to per ceptual phenomena is metaphysics (p. 10). Away with the question of reality! Our concepts and hypotheses are mere signs (p. 26), “arbitrary” (p. 27) constructions, and so forth. There is only one step from this to idealism, to the “physics of the believer,” which M. Pierre Duhem preaches in the Kantian spirit (Rey, p. 162; cf., p. 160). But the good Adler (Fritz)—also a Machian would-be Marxist!—could find nothing cleverer to do than to “correct” Duhem as follows: Duhem, he claims, eliminates the “realities concealed behind phenomena only as objects of theory, but not as objects of reality.” This is the familiar criticism of Kantianism from the standpoint of Hume and Berkeley.
But, of course, there can be no question of any conscious Kantianism on the part of Duhem. He is merely vacillating as is Mach, not knowing on what to base his relativism. In many passages he comes very close to dialectical materialism. He says that we know sound “such as it is in relation to us but not as it is in itself, in the sound-producing bodies. This reality, of which our sensations give us only the external and the veil, is made known to us by the theories of acoustics. They tell us that where our perceptions register only this appearance which we call sound, there really exists a very small and very rapid periodic movement,” etc. (p. 7). Bodies are not symbols of sensations, but sensations are symbols (or rather, images) of bodies. “The development of physics gives rise to a constant struggle between nature, which does not tire of offering new material, and reason, which does not tire of cognising” (p. 32). Nature is infinite, just as its smallest particle (including the electron) is infinite, but reason just as infinitely transforms “things-in-themselves” into “things-for-us.” “Thus, the struggle between reality and the laws of physics will continue indefinitely; to every law that physics may formulate, reality will sooner or later oppose a rude refutation in the form of a fact; but, indefatigable, physics will improve, modify, and complicate the refuted law” (p. 290). This would be a quite correct exposition of dialectical materialism if the author firmly held to the existence of this objective reality independent of humanity. “. . . The theory of physics is not a purely artificial system which is convenient today and unsuitable tomorrow . . . it is a classification, which becomes more and more natural, a reflection, which grows clearer and clearer, of the realities that the experimental method cannot contemplate face to face” (p. 445).
In this last phrase the Machian Duhem flirts with Kantian idealism: it is as if the way is being opened for a method other than the “experimental” one, and as if we cannot know the “things-in-themselves” directly, immediately, face to face. But if the theory of physics becomes more and more natural, that means that “nature,” reality, “reflected” by this theory, exists independently of our consciousness—and that is precisely the view of dialectical materialism.
In a word, the “physical” idealism of today, just as the “physiological” idealism of yesterday, merely means that one school of natural scientists in one branch of natural science has slid into a reactionary philosophy, being unable to rise directly and at once from metaphysical materialism to dialectical materialism. This step is being made, and will be made, by modern physics; but it is making for the only true method and the only true philosophy of natural science not directly, but by zigzags, not consciously but instinctively, not clearly perceiving its “final goal,” but drawing closer to it gropingly, hesitatingly, and sometimes even with its back turned to it. Modern physics is in travail; it is giving birth to dialectical materialism. The process of child-birth is painful. And in addition to a living healthy being, there are bound to be produced certain dead products, refuse fit only for the garbage-heap. And the entire school of physical idealism, the entire empirio-critical philosophy, together with empirio-symbolism, empirio-monism, and so on, and so forth, must be regarded as such refuse!
 Johannes Rehmke, Philosophie und Kantianismus [Philosophy and Kantianism], Eisenach, 1882, S. 15, et seq. —Lenin
 P. Duhern, La théorie physique, son objet et sa structure, Paris, 1906. —Lenin
 J. B. Stallo. The Concepts and Theories of Modern Physics, London, 1882, There are French and German translations. —Lenin
 Translator’s note to the German translation of Duhem, Leipzig, 1908, J. Barth. —Lenin
 The famous chemist, William Ramsay, says: “I have been frequently asked: ‘But is not electricity a vibration? How can wireless telegraphy be explained by the passage of little particles or corpuscles?’ The answer is: ‘Electricity is a thing ; it is (Ramsay’s italics) these minute corpuscles, but when they leave an object, a wave, like a wave of light, spreads through the ether, and this wave is used for wireless telegraphy’” (William Ramsay, Essays, Biographical and Chemical, London, 1908, p. 126). Having spoken about the transformation of radium into helium, Ramsay remarks: “At least one so-called element can no longer be regarded as ultimate matter, but is itself undergoing change into a simpler form of matter” (p. 160). “Now it is almost certain that negative electricity is a particular form of matter; and positive electricity is matter deprived of negative electricity—that is, minus this electric matter” (p. 176). “Now what is electricity? It used to be believed, formerly, that there were two kinds of electricity, one called positive and the other negative. At that time it would not have been possible to answer the question. But recent researches make it probable that what used to be called negativc electricity is really a substance. Indeed, the relative weight of its particles has been measured; each is about one seven hundredth of the mass of an atom of hydrogen. . . . Atoms of electricity are named ‘electrons’” (p. 196). If our Machians who write books and articles on philosophical subjects were capable of thinking, they would understand that the expression “matter disappears,” “matter is reduced to electricity,” etc., is only an epistemologically helpless expression of the truth that science is able to discover new forms of matter, new forms of material motion, to reduce the old forms to the new forms, and so on. —Lenin