Library:Vladimir Lenin/Materialism and empirio-criticism

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The theory of knowledge of empirio-criticism and of dialectical materialism

Part I

Sensations and complexes of sensations

The fundamental premises of the theory of knowledge of Mach and Avenarius are frankly, simply and clearly expounded by them in their early philosophical works. To these works we shall now turn, postponing for later treatment an examination of the corrections and emendations subsequently made by these writers.

Mach wrote in 1872:

“The task of science can only be:

1. To determine the laws of connection of ideas (Psychology).
2. To discover the laws of connection of sensations (Physics).
3. To explain the laws of connection between sensations and ideas (Psycho-physics).”

This is quite clear. The subject matter of physics is the connection between sensations and not between things or bodies, of which our sensations are the image. And in 1883, in his Mechanics, Mach repeats the same thought:

“Sensations are not ’symbols of things.’ The ’thing’ is rather a mental symbol for a complex of sensations of relative stability. Not the things (bodies) but colours, sounds, pressures, spaces, times (what we usually call sensations) are the real elements of the world.”

About this word “elements,” the fruit of twelve years of “reflection,” we shall speak later. At present let us note that Mach explicitly states here that things or bodies are complexes of sensations, and that he quite clearly sets up his own philosophical point of view against the opposite theory which holds that sensations are “symbols” of things (it would be more correct to say images or reflections of things). The latter theory is philosophical materialism. For instance, the materialist Frederick Engels—the not unknown collaborator of Marx and a founder of Marxism—constantly and without exception speaks in his works of things and their mental pictures or images (Gedanken-Abbilder), and it is obvious that these mental images arise exclusively from sensations. It would seem that this fundamental standpoint of the “philosophy of Marxism” ought to be known to everyone who speaks of it, and especially to anyone who comes out in print in the name of this philosophy. But because of the extraordinary confusion which our Machians have introduced, it becomes necessary to repeat what is generally known. We turn to the first section of Anti-Dühring and read: “. . . things and their mental images . . .”; or to the first section of the philosophical part, which reads:

“But whence does thought obtain these principles [i.e., the fundamental principles of all knowledge]? From itself? No . . . these forms can never be created and derived by thought out of itself, but only from the external world . . . the principles are not the starting point of the investigation [as Dühring who would be a materialist, but cannot consistently adhere to materialism, holds], but its final result; they are not applied to nature and human history, but abstracted from them; it is not nature and the realm of humanity which conform to these principles, but the principles are only valid in so far as they are in conformity with nature and history. That is the only materialistic conception of the matter, and Herr Dühring’s contrary conception is idealistic, makes things stand completely on their heads, and fashions the real world out of ideas” (ibid., p. 21).

Engels, we repeat, applies this “only materialistic conception” everywhere and without exception, relentlessly attacking Dühring for the least deviation from materialism to idealism. Anybody who reads Anti-Dühring and Ludwig Feuerbach with the slightest care will find scores of instances when Engels speaks of things and their reflections in the human brain, in our consciousness, thought, etc. Engels does not say that sensations or ideas are “symbols” of things, for consistent materialism must here use “image,” picture, or reflection instead of “symbol,” as we shall show in detail in the proper place. But the question here is not of this or that formulation of materialism, but of the opposition of materialism to idealism, of the difference between the two fundamental lines in philosophy. Are we to proceed from things to sensation and thought? Or are we to proceed from thought and sensation to things? The first line, i.e., the materialist line, is adopted by Engels. The second line, i.e., the idealist line, is adopted by Mach. No evasions, no sophisms (a multitude of which we shall yet encounter) can remove the clear and indisputable fact that Ernst Mach’s doctrine that things are complexes of sensations is subjective idealism and a simple rehash of Berkeleianism. If bodies are “complexes of sensations,” as Mach says, or “combinations of sensations,” as Berkeley said, it inevitably follows that the whole world is but my idea. Starting from such a premise it is impossible to arrive at the existence of other people besides oneself: it is the purest solipsism. Much as Mach, Avenarius, Petzoldt and the others may abjure solipsism, they cannot in fact escape solipsism without falling into howling logical absurdities. To make this fundamental element of the philosophy of Machism still clearer, we shall give a few additional quotations from Mach’s works. Here is a sample from the Analyse der Empfindungen; (I quote from Kotlyar’s Russian translation, published by Skirmunt, Moscow, 1907):

"We see a body with a point S. If we touch S, that is, bring it into contact with our body, we receive a prick. We can see S without feeling the prick. But as soon as we feel the prick we find S on the skin. Thus, the visible point is a permanent nucleus, to which, according to circumstances, the prick is attached as something accidental. By frequent repetitions of analogous occurrences we finally habituate ourselves to regard all properties of bodies as ’effects’ which proceed from permanent nuclei and are conveyed to the self through the medium of the body; which effects we call sensations . . .” (p. 20).

In other words, people “habituate” themselves to adopt the standpoint of materialism, to regard sensations as the result of the action of bodies, things, nature on our sense organs. This “habit,” so noxious to the philosophical idealists (a habit acquired by all mankind and all natural science!), is not at all to the liking of Mach, and he proceeds to destroy it:

“. . . Thereby, however, these nuclei are deprived of their entire sensible content and are converted into naked abstract symbols . . .”

An old song, most worthy Professor! This is a literal repetition of Berkeley who said that matter is a naked abstract symbol. But it is Ernst Mach, in fact, who goes naked, for if he does not admit that the “sensible content” is an objective reality, existing independently of us, there remains only a “naked abstract” I, an I infallibly written with a capital letter and italicised, equal to “the insane piano, which imagined that it was the sole existing thing in this world.” If the “sensible content” of our sensations is not the external world then nothing exists save this naked I engaged in empty “philosophical” acrobatics. A stupid and fruitless occupation!

“. . . It is then correct that the world consists only of our sensations. In which case we have knowledge only of sensations, and the assumption of those nuclei, and of their interaction, from which alone sensations proceed, turns out to be quite idle and superfluous. Such a view can only appeal to half-hearted realism or half-hearted criticism.”

We have quoted the sixth paragraph of Mach’s “anti-metaphysical observations” in full. It is a sheer plagiarism on Berkeley. Not a single idea, not a glimmer of thought, except that “we sense only our sensations.” From which there is only one possible inference, namely, that the “world consists only of my sensations.” The word “our” employed by Mach instead of “my” is employed illegitimately. By this word alone Mach betrays that “half-heartedness” of which he accuses others. For if the “assumption” of the existence of the external world is “idle,” if the assumption that the needle exists independently of me and that an interaction takes place between my body and the point of the needle is really “idle and superfluous,” then primarily the “assumption” of the existence of other people is idle and superfluous. Only I exist, and all other people, as well as the external world, come under the category of idle “nuclei.” Holding this point of view one cannot speak of “our” sensations; and when Mach does speak of them, it is only a betrayal of his own amazing half-heartedness. It only proves that his philosophy is a jumble of idle and empty words in which their author himself does not believe. Here is a particularly graphic example of Mach’s half heartedness and confusion. In § 6 of Chapter XI of the Analysis of Sensations we read:

“If I imagine that while I am experiencing sensations, I or someone else could observe my brain with all possible physical and chemical appliances, it would be possible to ascertain with what processes of the organism particular sensations are connected . . . ” (p. 197).

Very well! This means, then, that our sensations are connected with definite processes, which take place in the organism in general, and in our brain in particular? Yes, Mach very definitely makes this “assumption"—it would be quite a task not to make it from the standpoint of natural science! But is not this the very “assumption” of those very same “nuclei and their interaction” which our philosopher declared to be idle and superfluous? We are told that bodies are complexes of sensations; to go beyond that, Mach assures us, to regard sensations as a product of the action of bodies upon our sense-organs, is metaphysics, an idle and superfluous assumption, etc., à la Berkeley. But the brain is a body. Consequently, the brain also is no more than a complex of sensations. It follows, then, that with the help of a complex of sensations I (and I also am nothing but a complex of sensations) sense complexes of sensations. A delightful philosophy! First sensations are declared to be “the real elements of the world"; on this an “original” Berkeleianism is erected—and then the very opposite view is smuggled in, viz., that sensations are connected with definite processes in the organism. Are not these “processes” connected with an exchange of matter between the “organism” and the external world? Could this exchange of matter take place if the sensations of the particular organism did not give it an objectively correct idea of this external world? Mach does not ask himself such embarrassing questions when he mechanically jumbles fragments of Berkeleianism with the views of natural science, which instinctively adheres to the materialist theory of knowledge. . . . In the same paragraph Mach writes: “It is sometimes also asked whether (inorganic) ‘matter’ experiences sensation....” Does this mean that there is no doubt that organic matter experiences sensation? Does this mean that sensation is not something primary but that it is one of the properties of matter? Mach skips over all the absurdities of Berkeleianism! . . . “The question,” he avers, “is natural enough, if we proceed from the current widespread physical notions, according to which matter is the immediate and indisputably given reality, out of which everything, inorganic and organic, is constructed....” Let us bear in mind this truly valuable admission of Mach’s that the current widespread physical notions regard matter as the immediate reality, and that only one variety of this reality (organic matter) possesses the well-defined property of sensation. . . . Mach continues:

“Then, indeed, sensation must suddenly arise somewhere in this structure consisting of matter, or else have previously been present in the foundation. From our standpoint the question is a false one. For us matter is not what is primarily given. Rather, what is primarily given are the elements (which in a certain familiar relation are designated as sensations). . . . ”

What is primarily given, then, are sensations, although they are “connected” only with definite processes in organic matter! And while uttering such absurdities Mach wants to blame materialism ("the current widespread physical notion") for leaving unanswered the question whence sensation “arises.” This is a sample of the “refutation” of materialism by the fideists and their hangers-on. Does any other philosophical standpoint “solve” a problem before enough data for its solution has been collected? Does not Mach himself say in the very same paragraph: “So long as this problem (how far sensation extends in the organic world) has not been solved even in a single special case, no answer to the question is possible.”

The difference between materialism and “Machism” in this particular question thus consists in the following. Materialism, in full agreement with natural science, takes matter as primary and regards consciousness, thought, sensation as secondary, because in its well-defined form sensation is associated only with the higher forms of matter (organic matter), while “in the foundation of the structure of matter” one can only surmise the existence of a faculty akin to sensation. Such, for example, is the supposition of the well-known German scientist Ernst Haeckel, the English biologist Lloyd Morgan and others, not to speak of Diderot’s conjecture mentioned above. Machism holds to the opposite, the idealist point of view, and at once lands into an absurdity: since, in the first place, sensation is taken as primary, in spite of the fact that it is associated only with definite processes in matter organised in a definite way; and since, in the second place, the basic premise that bodies are complexes of sensations is violated by the assumption of the existence of other living beings and, in general, of other “complexes” besides the given great I.

The word “element,” which many naïve people (as we shall see) take to be some sort of a new discovery, in reality only obscures the question, for it is a meaningless term which creates the false impression that a solution or a step forward has been achieved. This impression is a false one, because there still remains to be investigated and reinvestigated how matter, apparently entirely devoid of sensation, is related to matter which, though composed of the same atoms (or electrons), is yet endowed with a well-defined faculty of sensation. Materialism clearly formulates the as yet unsolved problem and thereby stimulates the attempt to solve it, to undertake further experimental investigation. Machism, which is a species of muddled idealism, befogs the issue and side tracks it by means of the futile verbal trick, “element.”

Here is a passage from Mach’s latest, comprehensive and conclusive philosophical work that clearly betrays the falsity of this idealist trick. In his Knowledge and Error we read:

“While there is no difficulty in constructing (aufzubauen) every physical experience out of sensations, i.e., psychical elements, it is impossible to imagine (ist keine Möglichkeit abzusehen) how any psychical experience can be composed (darstellen) of the elements employed in modern physics, i.e., mass and motion (in their rigidity—Starrheit—which is serviceable only for this special science).”

Of the rigidity of the conceptions of many modern scientists and of their metaphysical (in the Marxist sense of the term, i.e., anti-dialectical) views, Engels speaks repeatedly and very precisely. We shall see later that it was just on this point that Mach went astray, because he did not understand or did not know the relation between relativism and dialectics. But this is not what concerns us here. It is important for us here to note how glaringly Mach’s idealism emerges, in spite of the confused—ostensibly new—terminology. There is no difficulty, you see, in constructing any physical element out of sensations, i.e., psychical elements! Oh yes, such constructions, of course, are not difficult, for they are purely verbal constructions, shallow scholasticism, serving as a loophole for fideism. It is not surprising after this that Mach dedicates his works to the immanentists; it is not surprising that the immanentists, who profess the most reactionary kind of philosophical idealism, welcome Mach with open arms. The “recent positivism” of Ernst Mach was only about two hundred years too late. Berkeley had already sufficiently shown that “out of sensations, i.e., psychical elements,” nothing can be “built” except solipsism. As regards materialism, against which Mach here, too, sets up his own views, without frankly and explicitly naming the “enemy,” we have already seen in the case of Diderot what the real views of the materialists are. These views do not consist in deriving sensation from the movement of matter or in reducing sensation to the movement of matter, but in recognising sensation as one of the properties of matter in motion. On this question Engels shared the standpoint of Diderot. Engels dissociated himself from the “vulgar” materialists, Vogt, Büchner and Moleschott, for the very reason, among others, that they erred in believing that the brain secretes thought in the same way as the liver secretes bile. But Mach, who constantly sets up his views in opposition to materialism, ignores, of course, all the great materialists—Diderot, Feuerbach, Marx and Engels—just as all other official professors of official philosophy do.

In order to characterise Avenarius’ earliest and basic view, let us take his first independent philosophical work, Philosophy as a Conception of the World According to the Principle of the Minimum Expenditure of Effort. Prolegomena to a Critique of Pure Experience, which appeared in 1876. Bogdanov in his Empirio-Monism (Bk. I, 2nd ed., 1905, p. 9, note) says that “in the development of Mach’s views, the starting point was philosophical idealism, while a realistic tinge was characteristic of Avenarius from the very beginning.” Bogdanov said so because he believed what Mach said (see Analysis of Sensations, Russian translation, p. 288). Bogdanov should not have believed Mach, and his assertion is diametrically opposed to the truth. On the contrary, Avenarius’ idealism emerges so clearly in his work of 1876 that Avenarius himself in 1891 was obliged to admit it. In the introduction to The Human Concept of the World Avenarius says: “He who has read my first systematic work, Philosophie, etc., will at once have presumed that I would have attempted to treat the problems of a criticism of pure experience from the ‘idealist’ standpoint” (Der menschliche Weltbegriff, 1891, Vorwort, S. ix [The Human Concept of the World, 1891, Foreword, p. ix]), but “the sterility of philosophical idealism compelled me to doubt the correctness of my previous path” (p. x). This idealist starting point of Avenarius’ is universally acknowledged in philosophical literature. Of the French writers I shall refer to Cauwelaert, who says that Avenarius’ philosophical standpoint in the Prolegomena is “monistic idealism.” Of the German writers, I shall name Rudolf Willy, Avenarius’ disciple, who says that “Avenarius in his youth—and particularly in his work of 1876—was totally under the spell (ganz im Banne) of so-called epistemological idealism.”

And, indeed, it would be ridiculous to deny the idealism in Avenarius’ Prolegomena, where he explicitly states that “only sensation can be thought of as the existing” (pp. 10 and 65 of the second German edition; all italics in quotations are ours). This is how Avenarius himself presents the contents of § 116 of his work. Here is the paragraph in full:

“We have recognised that the existing (das Seiende) is substance endowed with sensation; the substance falls away [it is “more economical,” don’t you see, there is “a lesser expenditure of effort” in thinking that there is no “substance” and that no external world exists!], sensation remains; we must then regard the existing as sensation, at the basis of which there is nothing which does not possess sensation (nichts Empfindungsloses).”

Sensation, then, exists without “substance,” i.e., thought exists without brain! Are there really philosophers capable of defending this brainless philosophy? There are! Professor Richard Avenarius is one of them. And we must pause for a while to consider this defence, difficult though it be for a normal person to take it seriously. Here, in §§ 89 and 90 of this same work, is Avenarius’ argument:

“. . . The proposition that motion produces sensation is based on apparent experience only. This experience, which includes the act of perception, consists, presumably, in the fact that sensation is generated in a certain kind of substance (brain) as a result of transmitted motion (excitation) and with the help of other material conditions (e.g., blood). However—apart from the fact that such generation has never itself (selbst) been observed—in order to construct the supposed experience, as an experience which is real in all its component parts, empirical proof, at least, is required to show that sensation, which assumedly is caused in a certain substance by transmitted motion, did not already exist in that substance in one way or another; so that the appearance of sensation cannot be conceived of in any other way than as a creative act on the part of the transmitted motion. Thus only by proving that where a sensation now appears there was none previously, not even a minimal one, would it be possible to establish a fact which, denoting as it does some act of creation, contradicts all the rest of experience and radically changes all the rest of our conception of nature (Naturanschauung). But such proof is not furnished by any experience, and cannot be furnished by any experience; on the contrary, the notion of a state of a substance totally devoid of sensation which subsequently begins to experience sensation is only a hypothesis. But this hypothesis merely complicates and obscures our understanding instead of simplifying and clarifying it. Should the so-called experience, viz., that the sensation is caused by a transmitted motion in a substance that begins to perceive from this moment, prove upon closer examination to be only apparent, there still remains sufficient material in the content of the experience to ascertain at least the relative origin of sensation from conditions of motion, namely, to ascertain that the sensation which is present, although latent or minimal, or for some other reason not manifest to the consciousness, becomes, owing to transmitted motion, released or enhanced or made manifest to the consciousness. However, even this bit of the remaining content of experience is only an appearance. Were we even by an ideal observation to trace the motion proceeding from the moving substance A, transmitted through a series of intermediate centres and reaching the substance B, which is endowed with sensation, we should at best find that sensation in substance B is developed or becomes enhanced simultaneously with the reception of the incoming motion—but we should not find that this occurred as a consequence of the motion. . . .”

We have purposely quoted this refutation of materialism by Avenarius in full, in order that the reader may see to what truly pitiful sophistries “recent” empirio-critical philosophy resorts. We shall compare with the argument of the idealist Avenarius the materialist argument of—Bogdanov, if only to punish Bogdanov for his betrayal of materialism! In long bygone days, fully nine years ago, when Bogdanov was half “a natural-historical materialist” (that is, an adherent of the materialist theory of knowledge, to which the overwhelming majority of contemporary scientists instinctively hold), when he was only half led astray by the muddled Ostwald, he wrote:

“From ancient times to the present day, descriptive psychology has adhered to the classification of the facts of consciousness into three categories: the domain of sensations and ideas, the domain of emotions and the domain of impulses. . . . To the first category belong the images of phenomena of the outer or inner world, as taken by themselves in consciousness. . . . Such an image is called a ‘sensation’ if it is directly produced through the sense-organs by its corresponding external phenomenon.”

And a little farther on he says: “Sensation . . . arises in consciousness as a result of a certain impulse from the external environment transmitted by the external sense-organs” (p. 222). And further: “Sensation is the foundation of mental life; it is its immediate connection with the external world” (p. 240). “At each step in the process of sensation a transformation of the energy of external excitation into a state of consciousness takes place” (p. 133). And even in 1905 when with the gracious assistance of Ostwald and Mach Bogdanov had already abandoned the materialist standpoint in philosophy for the idealist standpoint, he wrote (from forgetfulness!) in his Empirio-Monism:

“As is known, the energy of external excitation, transformed at the nerve-ends into a ‘telegraphic’ form of nerve current (still insufficiently investigated but devoid of all mysticism), first reaches the neurons that are located in the so-called ‘lower’ centres—ganglial, cerebro-spinal, subcortical, etc.” (Bk. I, 2nd ed., 1905, p. 118.)

For every scientist who has not been led astray by professorial philosophy, as well as for every materialist, sensation is indeed the direct connection between consciousness and the external world; it is the transformation of the energy of external excitation into a state of consciousness. This transformation has been, and is, observed by each of us a million times on every hand. The sophism of idealist philosophy consists in the fact that it regards sensation as being not the connection between consciousness and the external world, but a fence, a wall, separating consciousness from the external world—not an image of the external phenomenon corresponding to the sensation, but as the “sole entity.” Avenarius gave but a slightly changed form to this old sophism, which had been already worn threadbare by Bishop Berkeley. Since we do not yet know all the conditions of the connection we are constantly observing between sensation and matter organised in a definite way, let us therefore acknowledge the existence of sensation alone—that is what the sophism of Avenarius reduces itself to.

To conclude our description of the fundamental idealist premises of empirio-criticism, we shall briefly refer to the English and French representatives of this philosophical trend. Mach explicitly says of Karl Pearson, the Englishman, that he (Mach) is “in agreement with his epistemological (erkenntniskritischen) views on all essential points” (Mechanik, ed. previously cited, p. ix). Pearson in turn agrees with Mach. For Pearson “real things” are “sense-impressions.” He declares the recognition of things outside the boundaries of sense impressions to be metaphysics. Pearson fights materialism with great determination (although he does not know Feuerbach, or Marx and Engels); his arguments do not differ from those analysed above. However, the desire to masquerade as a materialist is so foreign to Pearson (that is a specialty of the Russian Machians), Pearson is so—incautious, that he invents no “new” names for his philosophy and simply declares that his views and those of Mach are “idealist” (ibid., p. 326)! He traces his genealogy directly to Berkeley and Hume. The philosophy of Pearson, as we shall repeatedly find, is distinguished from that of Mach by its far greater integrity and consistency.

Mach explicitly declares his solidarity with the French physicists, Pierre Duhem and Henri Poincaré. We shall have occasion to deal with the particularly confused and inconsistent philosophical views of these writers in the chapter on the new physics. Here we shall content ourselves with noting that for Poincaré things are “groups of sensations” and that a similar view is casually expressed by Duhem.

We shall now proceed to examine how Mach and Avenarius, having admitted the idealist character of their original views, corrected them in their subsequent works.

“The discovery of the world-elements”

Such is the title under which Friedrich Adler, lecturer at the University of Zürich, probably the only German author also anxious to supplement Marx with Machism, writes of Mach. And this naïve university lecturer must be given his due: in his simplicity of heart he does Machism more harm than good. At least, he puts the question point-blank—did Mach really “discover the world-elements"? If so, then, only very backward and ignorant people, of course, can still remain materialists. Or is this discovery a return on the part of Mach to the old philosophical errors?

We saw that Mach in 1872 and Avenarius in 1876 held a purely idealist view; for them the world is our sensation. In 1883 Mach’s Mechanik appeared, and in the preface to the first edition Mach refers to Avenarius’ Prolegomena, and greets his ideas as being “very close” (sehr verwandte) to his own philosophy. Here are the arguments in the Mechanik concerning the elements:

“All natural science can only picture and represent (nachbilden und vorbilden) complexes of those elements which we ordinarily call sensations. It is a matter of the connection of these elements. . . The connection of A (heat) with B (flame) is a problem of physics, that of A and N (nerves) a problem of physiology. Neither exists separately; both exist in conjunction. Only temporarily can we neglect either. Even processes that are apparently purely mechanical, are thus always physiological” (op. cit., German ed., p. 498).

We find the same in the Analysis of Sensations:

“Wherever . . . the terms ‘sensation,’ ‘complex of sensations,’ are used alongside of or in place of the terms ‘element,’ ‘complex of elements,’ it must be borne in mind that it is only in this connection [namely, in the connection of A, B, C with K, L, M, that is, in the connection of “complexes which we ordinarily call bodies” with “the complex which we call our body”] and relation, only in this functional dependence that the elements are sensations. In another functional dependence they are at the same time physical objects” (Russian translation, pp. 23 and 17).

“A colour is a physical object when we consider its dependence, for instance, upon the source of illumination (other colours, temperatures, spaces and so forth). When we, however, consider its dependence upon the retina (the elements K, L, M), it is a psychological object, a sensation” (ibid., p. 24).

Thus the discovery of the world-elements amounts to this:

1. all that exists is declared to be sensation,
2. sensations are called elements,
3. elements are divided into the physical and the psychical; the latter is that which depends on the human nerves and the human organism generally; the former does not depend on them;
4. the connection of physical elements and the connection of psychical elements, it is declared, do not exist separately from each other; they exist only in conjunction;
5. it is possible only temporarily to leave one or the other connection out of account;
6. the “new” theory is declared to be free from “one-sidedness.”^[2]

Indeed, it is not one-sidedness we have here, but an in coherent jumble of antithetical philosophical points of view. Since you base yourself only on sensations you do not correct the “one-sidedness” of your idealism by the term “element,” but only confuse the issue and cravenly hide from your own theory. In a word, you eliminate the antithesis between the physical and psychical,^[3] between materialism (which regards nature, matter, as primary) and idealism (which regards spirit, mind, sensation as primary); indeed, you promptly restore this antithesis; you restore it surreptitiously, retreating from your own fundamental premise! For, if elements are sensations, you have no right even for a moment to accept the existence of “elements” independently of my nerves and my mind. But if you do admit physical objects that are independent of my nerves and my sensations and that cause sensation only by acting upon my retina—you are disgracefully abandoning your “one-sided” idealism and adopting the standpoint of “one-sided” materialism! If colour is a sensation only depending upon the retina (as natural science compels you to admit), then light rays, falling upon the retina, produce the sensation of colour. This means that outside us, independently of us and of our minds, there exists a movement of matter, let us say of ether waves of a definite length and of a definite velocity, which, acting upon the retina, produce in man the sensation of a particular colour. This is precisely how natural science regards it. It explains the sensations of various colours by the various lengths of light-waves existing outside the human retina, outside man and independently of him. This is materialism: matter acting upon our sense-organs produces sensation. Sensation depends on the brain, nerves, retina, etc., i.e., on matter organised in a definite way. The existence of matter does not depend on sensation. Matter is primary. Sensation, thought, consciousness are the supreme product of matter organised in a particular way. Such are the views of materialism in general, and of Marx and Engels in particular. Mach and Avenarius secretly smuggle in materialism by means of the word “element,” which supposedly frees their theory of the “one-sidedness” of subjective idealism, supposedly permits the assumption that the mental is dependent on the retina, nerves and so forth, and the assumption that the physical is independent of the human organism. In fact, of course, the trick with the word “element” is a wretched sophistry, for a materialist who reads Mach and Avenarius will immediately ask: what are the “elements"? It would, indeed, be childish to think that one can dispose of the fundamental philosophical trends by inventing a new word. Either the “element” is a sensation, as all empirio-criticists, Mach, Avenarius, Petzoldt,^[4] etc., maintain—in which case your philosophy, gentlemen, is idealism vainly seeking to hide the nakedness of its solipsism under the cloak of a more “objective” terminology; or the “element” is not a sensation—in which case absolutely no thought whatever is attached to the “new” term; it is merely an empty bauble.

Take Petzoldt, for instance, the last word in empirio-criticism, as V. Lesevich, the first and most outstanding Russian empirio-criticist describes him.^[5] Having defined elements as sensations, he says in the second volume of the work mentioned:

“In the statement that ‘sensations are the elements of the world’ one must guard against taking the term ‘sensation’ as denoting something only subjective and therefore ethereal, transforming the ordinary picture of the world into an illusion (Verflüchtigendes).”^[6]

One speaks of what hurts one most! Petzoldt feels that the world “evaporates” (verflüchtigt sich), or becomes transformed into an illusion, when sensations are regarded as world-elements. And the good Petzoldt imagines that he helps matters by the reservation that sensation must not be taken as something only subjective! Is this not a ridiculous sophistry? Does it make any difference whether we “take” sensation as sensation or whether we try to stretch the meaning of the term? Does this do away with the fact that sensations in man are connected with normally functioning nerves, retina, brain, etc., that the external world exists independently of our sensations? If you are not trying to evade the issue by a subterfuge, if you are really in earnest in wanting to “guard” against subjectivism and solipsism, you must above all guard against the fundamental idealist premises of your philosophy; you must replace the idealist line of your philosophy (from sensations to the external world) by the materialist line (from the external world to sensations); you must abandon that empty and muddled verbal embellishment, “element,” and simply say that colour is the result of the action of a physical object on the retina, which is the same as saying that sensation is a result of the action of matter on our sense-organs.

Let us take Avenarius. The most valuable material on the question of the “elements” is to be found in his last work (and, it might be said, the most important for the comprehension of his philosophy), Notes on the Concept of the Subject of Psychology.^[7] The author, by the way, here gives a very “graphic” table (Vol. XVIII, p. 410), the main part of which we reproduce here:

Things, or the substantial	Elements, complexes of elements: Corporeal things
Thoughts, or the mental	Incorporeal things, recollections and fantasies

Compare this with what Mach says after all his elucidation of the “elements” (Analysis of Sensations, p. 33): “It is not bodies that produce sensations, but complexes of elements (complexes of sensations) that make up bodies.” Here you have the “discovery of the world-elements” that overcomes the one-sidedness of idealism and materialism! At first we are assured that the “elements” are something new, both physical and psychical at the same time; then a little correction is surreptitiously inserted: instead of the crude, materialist differentiation of matter (bodies, things) and the psychical (sensations, recollections, fantasies) we are presented with the doctrine of “recent positivism” regarding elements substantial and elements mental. Adler (Fritz) did not gain very much from “the discovery of the world-elements"!

Bogdanov, arguing against Plekhanov in 1906, wrote:

“. . . I cannot own myself a Machian in philosophy. In the general philosophical conception there is only one thing I borrowed from Mach—the idea of the neutrality of the elements of experience in relation to the ‘physical’ and ‘psychical’ and the dependence of these characteristics solely on the connection of experience.” (Empirio-Monism, Bk. III, St. Petersburg, 1906, p. xli.)

This is as though a religious man were to say—I cannot own myself a believer in religion, for there is “only one thing” I have borrowed from the believers—the belief in God. This “only one thing” which Bogdanov borrowed from Mach is the basic error of Machism, the basic falsity of its entire philosophy. Those deviations of Bogdanov’s from empirio-criticism to which he himself attaches great significance are in fact of entirely secondary importance and amount to nothing more than inconsiderable private and individual differences between the various empirio-criticists who are approved by Mach and who approve Mach (we shall speak of this in greater detail later). Hence when Bogdanov was annoyed at being confused with the Machians he only revealed his failure to understand what radically distinguishes materialism from what is common to Bogdanov and to all other Machians. How Bogdanov developed, improved or worsened Machism is not important What is important is that he has abandoned the materialist standpoint and has thereby inevitably condemned himself to confusion and idealist aberrations.

In 1899, as we saw, Bogdanov had the correct standpoint when he wrote: “The image of the man before me, directly given to me by vision, is a sensation.”^[8] Bogdanov did not trouble to give a criticism of this earlier position of his. He blindly believed Mach and began to repeat after him that the “elements” of experience are neutral in relation to the physical and psychical. “As has been established by recent positivist philosophy,” wrote Bogdanov in Book I of Empirio-Monism (2nd ed., p. 90), “the elements of psychical experience are identical with the elements of experience in general, as they are identical with the elements of physical experience.” Or in 1906 (Bk. III, p. xx): “as to ‘idealism,’ can it be called idealism merely on the grounds that the elements of ‘physical experience’ are regarded as identical with the elements of ‘psychical experience,’ or with elementary sensations—when this is simply an indubitable fact?”

Here we have the true source of all Bogdanov’s philosophical misadventures, a source which he shares with the rest of the Machians. We can and must call it idealism when “the elements of physical experience” (i.e., the physical, the external world, matter) are regarded as identical with sensations, for this is sheer Berkeleianism. There is not a trace here of recent philosophy, or positivist philosophy, or of indubitable fact. It is merely an old, old idealist sophism. And were one to ask Bogdanov how he would prove the “indubitable fact” that the physical is identical with sensations, one would get no other argument save the eternal refrain of the idealists: I am aware only of my sensations; the “testimony of self-consciousness” (die Aussage des Selbstbewusstseins) of Avenarius in his Prolegomena (2nd German ed., § 93, p. 56); or: “in our experience [which testifies that “we are sentient substance”] sensation is given us with more certainty than is substantiality” (ibid., § 91, p. 55), and so on and so forth. Bogdanov (trusting Mach) accepted a reactionary philosophical trick as an “indubitable fact.” For, indeed, not a single fact was or could be cited which would refute the view that sensation is an image of the external world—a view which was shared by Bogdanov in 1899 and which is shared by natural science to this day. In his philosophical wanderings the physicist Mach has completely strayed from the path of “modern science.” Regarding this important circumstance, which Bogdanov overlooked, we shall have much to say later.

One of the circumstances which helped Bogdanov to jump so quickly from the materialism of the natural scientists to the muddled idealism of Mach was (apart from the influence of Ostwald) Avenarius’ doctrine of the dependent and independent series of experience. Bogdanov himself expounds the matter in Book I of his Empirio-Monism thus:

“In so far as the data of experience appear in dependence upon the state of the particular nervous system, they form the psychical world of the particular person, in so far as the data of experience are taken outside of such a dependence, we have before us the physical world. Avenarius therefore characterises these two realms of experience respectively as the dependent series and the independent series of experience” (p. 18).

That is just the whole trouble, the doctrine of the independent (i.e., independent of human sensation) “series” is a surreptitious importation of materialism, which, from the standpoint of a philosophy that maintains that bodies are complexes of sensations, that sensations are “identical” with physical “elements,” is illegitimate, arbitrary, and eclectic. For once you have recognised that the source of light and light-waves exists independently of man and the human consciousness, that colour is dependent on the action of these waves upon the retina, you have in fact adopted the materialist standpoint and have completely destroyed all the “indubitable facts” of idealism, together with all “the complexes of sensations,” the elements discovered by recent positivism, and similar nonsense.

That is just the whole trouble. Bogdanov (like the rest of the Russian Machians) has never looked into the idealist views originally held by Mach and Avenarius, has never understood their fundamental idealist premises, and has therefore failed to discover the illegitimacy and eclecticism of their subsequent attempts to smuggle in materialism surreptitiously. Yet, just as the initial idealism of Mach and Avenarius is generally acknowledged in philosophical literature, so is it generally acknowledged that subsequently empirio-criticism endeavoured to swing towards materialism. Cauwelaert, the French writer quoted above, asserts that Avenarius’ Prolegomena is “monistic idealism,” The Critique of Pure Experience^[9] (1888–90) is “absolute realism,” while The Human Concept of the World (1891) is an attempt “to explain” the change. Let us note that the term realism is here employed as the antithesis of idealism. Following Engels, I use only the term materialism in this sense, and consider it the sole correct terminology, especially since the term “realism” has been bedraggled by the positivists and the other muddleheads who oscillate between materialism and idealism. For the present it will suffice to note that Cauwelaert had the indisputable fact in mind that in the Prolegomena (1876) sensation, according to Avenarius, is the only entity, while “substance"—in accordance with the principle of “the economy of thought"!—is eliminated, and that in the Critique of Pure Experience the physical is taken as the independent series, while the psychical and, consequently, sensations, are taken as the dependent series.

Avenarius’ disciple Rudolf Willy likewise admits that Avenarius was a “complete” idealist in 1876, but subsequently “reconciled” (Ausgleich) “naïve realism” (i.e., the instinctive, unconscious materialist standpoint adopted by humanity, which regards the external world as existing independently of our minds) with this teaching (loc. cit.).

Oskar Ewald, the author of the book Avenarius as the Founder of Empirio-Criticism, says that this philosophy combines contradictory idealist and “realist” (he should have said materialist) elements (not in Mach’s sense, but in the human sense of the term element). For example, “the absolute [method of consideration] would perpetuate naïve realism, the relative would declare exclusive idealism as permanent."^[10] Avenarius calls the absolute method of consideration that which corresponds to Mach’s connection of “elements” outside our body, and the relative that which corresponds to Mach’s connection of “elements” dependent on our body.

But of particular interest to us in this respect is the opinion of Wundt, who himself, like the majority of the above mentioned writers, adheres to the confused idealist standpoint, but who has analysed empirio-criticism perhaps more attentively than all the others. p. Yushkevich has the following to say in this connection: “It is interesting to note that Wundt regards empirio-criticism as the most scientific form of the latest type of materialism,”^[11] i.e., the type of those materialists who regard the spiritual as a function of corporeal processes (and whom—we would add—Wundt defines as standing midway between Spinozism^[19] and absolute materialism^[12]).

True, this opinion of Wundt’s is extremely interesting. But what is even more “interesting” is Mr. Yushkevich’s attitude towards the books and articles on philosophy of which he treats. This is a typical example of the attitude of our Machians to such matters. Gogol’s Petrushka^[20] used to read and find it interesting that letters always combined to make words. Mr. Yushkevich read Wundt and found it “interesting” that Wundt accused Avenarius of materialism. If Wundt is wrong, why not refute him? If he is right, why not explain the antithesis between materialism and empirio-criticism? Mr. Yushkevich finds what the idealist Wundt says “interesting,” but this Machian regards it as a waste of effort to endeavour to go to the root of the matter (probably on the principle of “the economy of thought”). . .

The point is that by informing the reader that Wundt accuses Avenarius of materialism, and by not informing him that Wundt regards some aspects of empirio-criticism as materialism and others as idealism and holds that the connection between the two is artificial, Yushkevich entirely distorted the matter. Either this gentleman absolutely does not understand what he reads, or he was prompted by a desire to indulge in false self-praise with the help of Wundt, as if to say: you see, the official professors regard us, too, as materialists, and not as muddleheads.

The above-mentioned article by Wundt constitutes a large book (more than 300 pages), devoted to a detailed analysis first of the immanentist school, and then of the empirio-criticists. Why did Wundt connect these two schools? Because he considers them closely akin ; and this opinion, which is shared by Mach, Avenarius, Petzoldt and the immanentists is, as we shall see later, entirely correct. Wundt shows in the first part of this article that the immanentists are idealists, subjectivists and adherents of fideism. This, too, as we shall see later, is a perfectly correct opinion, although Wundt expounds it with a superfluous ballast of professorial erudition, with superfluous niceties and reservations, which is to be explained by the fact that Wundt himself is an idealist and fideist. He reproaches the immanentists not because they are idealists and adherents of fideism, but because, in his opinion, they arrive at these great principles by incorrect methods. Further, the second and third parts of Wundt’s article are devoted to empirio-criticism. There he quite definitely points out that very important theoretical propositions of empirio-criticism (e.g., the interpretation of “experience” and the “principal co-ordination,” of which we shall speak later) are identical with those held by the immanentists (die empiriokritische in Uebereinstimmung mit der immanenten Philosophie annimmt, S. 382). Other of Avenarius’ theoretical propositions are borrowed from materialism, and in general empirio-criticism is a “motley” (bunte Mischung, ibid., S. 57), in which the “various component elements are entirely heterogeneous” (an sich einander völlig heterogen sind, S. 56).

Wundt regards Avenarius’ doctrine of the “independent vital series,” in particular, as one of the materialist morsels of the Avenarius-Mach hotchpotch. If you start from the “system C” (that is how Avenarius—who was very fond of making erudite play of new terms—designates the human brain or the nervous system in general), and if the mental is for you a function of the brain, then this “system C” is a “metaphysical substance"—says Wundt (ibid., p. 64), and your doctrine is materialism. It should be said that many idealists and all agnostics (Kantians and Humeans included) call the materialists metaphysicians, because it seems to them that to recognise the existence of an external world independent of the human mind is to transcend the bounds of experience. Of this terminology and its utter incorrectness from the point of view of Marxism, we shall speak in its proper place. Here it is important to note that the recognition of the “independent” series by Avenarius (and also by Mach, who expresses the same idea in different words) is, according to the general opinion of philosophers of various parties, i.e., of various trends in philosophy, an appropriation from materialism. If you assume that everything that exists is sensation, or that bodies are complexes of sensations, you cannot, without violating all your fundamental premises, all “your” philosophy, arrive at the conclusion that the physical exists independently of our minds, and that sensation is a function of matter organised in a definite way. Mach and Avenarius, in their philosophy, combine fundamental idealist premises with individual materialist deductions for the very reason that their theory is an example of that “pauper’s broth of eclecticism”^[21] of which Engels speaks with just contempt.^[13]

This eclecticism is particularly marked in Mach’s latest philosophical work, Knowledge and Error, 2nd edition, 1906. We have already seen that Mach there declared that “there is no difficulty in constructing every physical element out of sensation, i.e., out of psychical elements,” and in the same book we read: “Dependencies outside the boundary U [ = Umgrenzung, i.e., “the spatial boundary of our body,” S. 8] are physics in the broadest sense” (S. 323, § 4). “To obtain those dependencies in a pure state (rein erhalten) it is necessary as much as possible to eliminate the influence of the observer, that is, of those elements that lie within U” (loc. cit.). Well, well, the titmouse first promised to set the sea on fire. . . i.e., to construct physical elements from psychical elements, and then it turns out that physical elements lie beyond the boundary of psychical elements, “which lie within our body”! A remarkable philosophy!

Another example:

“A perfect (vollkommenes) gas, a perfect liquid, a perfect elastic body, does not exist; the physicist knows that his fictions only approximate to the facts and arbitrarily simplify them; he is aware of the divergence, which cannot be eliminated” (S. 418, § 30).

What divergence (Abweichung) is meant here? The divergence of what from what? Of thought (physical theory) from the facts. And what are thoughts, ideas? Ideas are the “tracks of sensations” (S. 9). And what are facts? Facts are “complexes of sensations.” And so, the divergence of the tracks of sensations from complexes of sensations cannot be eliminated.

What does this mean? It means that Mach forgets his own theory and, when treating of various problems of physics, speaks plainly, without idealist twists, i.e., materialistically. All the “complexes of sensations” and the entire stock of Berkeleian wisdom vanish. The physicists’ theory proves to be a reflection of bodies, liquids, gases existing outside us and independently of us, a reflection which is, of course, approximate; but to call this approximation or simplification “arbitrary” is wrong. In fact, sensation is here regarded by Mach just as it is regarded by all science which has not been “purified” by the disciples of Berkeley and Hume, viz., as an image of the external world. Mach’s own theory is subjective idealism; but when the factor of objectivity is required, Mach unceremoniously inserts into his arguments the premises of the contrary, i.e., the materialist, theory of knowledge. Eduard von Hartmann, a consistent idealist and consistent reactionary in philosophy, who sympathises with the Machians’ fight against materialism, comes very close to the truth when he says that Mach’s philosophical position is a “mixture (Nichtunterscheidung) of naïve realism and absolute illusionism”.^[14] That is true. The doctrine that bodies are complexes of sensations, etc., is absolute illusionism, i.e., solipsism; for from this standpoint the world is nothing but my illusion. On the other hand, Mach’s afore-mentioned argument, as well as many other of his fragmentary arguments, is what is known as “naïve realism,” i.e., the materialist theory of knowledge unconsciously and instinctively taken over from the scientists.

Avenarius and the professors who follow in his footsteps attempt to disguise this mixture by the theory of the “principal co-ordination.” We shall proceed to examine this theory presently, but let us first finish with the charge that Avenarius is a materialist. Mr. Yushkevich, to whom Wundt’s opinion which he failed to understand seemed so interesting, was either himself not enough interested to learn, or else did not condescend to inform the reader, how Avenarius’ nearest disciples and successors reacted to this charge. Yet this is necessary to clarify the matter if we are interested in the relation of Marx’s philosophy, i.e., materialism, to the philosophy of empirio-criticism. Moreover, if Machism is a muddle, a mixture of materialism and idealism, it is important to know whither this current turned—if we may so express it—after the official idealists began to disown it because of its concessions to materialism.

Wundt was answered, among others, by two of Avenarius’ purest and most orthodox disciples, J. Petzoldt and Fr. Carstanjen. Petzoldt, with haughty resentment, repudiated the charge of materialism, which is so degrading to a German professor, and in support referred to—what do you think?—Avenarius’ Prolegomena, where, supposedly, the concept of substance has been annihilated! A convenient theory, indeed, that can be made to embrace both purely idealist works and arbitrarily assumed materialist premises! Avenarius’ Critique of Pure Experience, of course, does not contradict this teaching, i.e., materialism, writes Petzoldt, but neither does it contradict the directly opposite spiritualist doctrine.^[15] An excellent defence! This is exactly what Engels called “a pauper’s broth of eclecticism.” Bogdanov, who refuses to own himself a Machian and who wants to be considered a Marxist (in philosophy), follows Petzoldt. He asserts that “empirio-criticism is not . . . concerned with materialism, or with spiritualism, or with metaphysics in general,”^[16] that “truth . . . does not lie in the ‘golden mean’ between the conflicting trends [materialism and spiritualism], but lies out side of both".^[17] What appeared to Bogdanov to be truth is, as a matter of fact, confusion, a wavering between materialism and idealism.

Carstanjen, rebutting Wundt, said that he absolutely repudiated this “importation (Unterschiebung) of a materialist element” which is utterly foreign to the critique of pure experience.”.^[18] “Empirio-criticism is scepticism χαι εςοχην (pre-eminently) in relation to the content of the concepts.” There is a grain of truth in this insistent emphasis on the neutrality of Machism; the amendment made by Mach and Avenarius to their original idealism amounts to partial concessions to materialism. Instead of the consistent standpoint of Berkeley—the external world is my sensation—we some times get the Humean standpoint—I exclude the question whether or not there is anything beyond my sensations. And this agnostic standpoint inevitably condemns one to vacillate between materialism and idealism.

The philosophical idealists as comrades-in-arms and successors of empirio-criticism

The recent revolution in natural science and philosophical idealism

Empirio-criticism and historical materialism