Source: Georgi Plekhanov, Selected Philosophical Works, Volume 3 (Progress Publishers, Moscow, 1976), pp.64-83;
Transcribed: for the Marxist Internet Archive by Paul Flewers.
According to the Soviet editors: ‘The second edition of Friedrich Engels’ Ludwig Feuerbach and the End of Classical German Philosophy, translated into Russian by Plekhanov, was issued in Geneva in 1905. The first Russian edition was published in 1892.’
Much water has flowed under the bridges since the first Russian edition of this pamphlet appeared. In the Preface to that edition, I said that the triumphant reactionaries in our country were donning philosophical robes and that for the struggle against this reaction the Russian socialists would inevitably have to study philosophy. My premonition was entirely confirmed by subsequent events. The Russian socialists – and I had and have in mind the Social-Democrats – had indeed to take up philosophy. But as they took it up very late and, to use a popular expression, were not exactly pulling together, the results have not been particularly gratifying. At times one almost regretted that books on philosophy had ever fallen into the hands of our comrades, because they were unable to take a critical attitude to the authors they were studying and finished by themselves falling under the influence of these authors. Since contemporary philosophy, not only in Russia but in the West too, bears the imprint of reaction, its reactionary content found its way into the heads of revolutionaries giving rise to the utmost confusion which sometimes received the bombastic title of criticism of Marx and sometimes bore the more modest name of combination of Marxism with the philosophical views of one or other of the bourgeois ideologists (neo-Kantians, Mach, Avenarius and others). There is not the slightest doubt that Marxism can be combined with anything, even with spiritualism; the whole question is how this may be done. Even the least intelligent person cannot answer this otherwise than by pointing to eclecticism. With the aid of eclecticism one may ‘combine’ anything with everything that comes into one’s head. But eclecticism never produced anything good either in theory or in practice. Fichte said: ‘To philosophise means not to act; to act means not to philosophise’, and this is quite true. However, it is no less true to say that only a consistently thinking person is capable of being consistent in his activity. And for us who claim the honour to represent the most revolutionary class that has at any time appeared on the historical scene, consistency is obligatory under pain of treachery to our cause.
What is behind the desire to combine Marxism now with one, now with another of the bourgeois ideologies?
First of all fashion.
Nekrasov says about one of his heroes:
What the latest book tells him
Lies upmost in his heart.
Such heroes can always be found; they make their way into every camp. Unfortunately, we meet them in ours too.
We had a crop of them in the second half of the nineties, when for many and many of our ‘intellectuals’ the ‘latest book’ lying ‘upmost in the heart’ was Marxism itself. It seemed as though such ‘intellectuals’ had been deliberately created by history in order to promote the ‘combination’ of Marxism with other ‘latest books’.  We have no regrets for them; they were empty-headed people anyway.
But it is a pity that more serious comrades, too, often feel the urge to ‘combine’. The explanation here is not the craze for fashion. Here we have something which, though very harmful and regrettable in itself, reveals the presence of good intentions.
Imagine that a particular comrade feels the need to work out for himself an orderly world-outlook; this comrade has mastered – more or less well – the philosophical-historical aspect of Marx’s teaching, but the strictly philosophical aspect of this teaching is still obscure and inaccessible to him. In the circumstances, he decides that this aspect of Marx’s teaching has still not been ‘worked out’, and he sets about ‘working it out’ himself. When he is engaged on this – not very easy – task, some representative of bourgeois ‘criticism’ turns up and appears to bring at least a little semblance of order where nothing but chaos had hitherto seemed to prevail. Our inquisitive comrade, who is inadequately prepared and insufficiently independent in his search for philosophical truth, easily succumbs to the influence of this bourgeois ‘critic’. And lo, we have a ready-made ‘combiner’. His intentions were good, but they turned out badly.
No, whatever our opponents may say, one thing is indisputable: the efforts to ‘combine’ the theory of Marx with other theories which, to use a German expression, are a slap in the face for that theory, reveal a striving to achieve an orderly world-outlook, but at the same time they expose a weakness of thought, an inability strictly and consistently to adhere to one fundamental principle. In other words, an inability to comprehend Marx.
How can one help this sad state of affairs? I do not see any other way than to disseminate the correct view of the philosophy of Marx and Engels. And in this respect, I think the present pamphlet can do very much.
More than once I myself have heard the question: why cannot historical materialism be combined with the transcendental idealism of Kant, the empirio-criticism of Avenarius, the philosophy of Mach, and so on? I have always replied to this in almost the same terms I shall use now. As regards Kant, my comments (see page 95) show how it is utterly impossible to ‘combine’ the philosophical doctrine of Kant with the theory of development.  The views of Mach and Avenarius, which are the latest variety of Hume’s philosophy, are no more capable of being combined with the theory of development than is Kant’s philosophy. To hold consistently those views is to arrive at solipsism, that is to say, to a denial of the existence of all people apart from oneself. Don’t think we are joking, reader. Although Mach protests energetically against the identification of his philosophy with Berkeley’s  subjective idealism, he thereby demonstrates only his own inconsistency. If bodies or things are only mental symbols of our sensations (more exactly, of groups, complexes of sensations) and if they do not exist outside our consciousness – and such is Mach’s theory – subjective idealism and solipsism can be rejected only by means of a howling inconsistency. It is not for nothing that one of Mach’s pupils, Hans Cornelius, in his book Einleitung in die Philosophie (München, 1903), comes close to solipsism. He states (page 322) that science cannot, either affirmatively or negatively, resolve for man the question: is there any kind of psychical life apart from one’s own? This is incontestable from the point of view of Machism; but if I still have doubts about the existence of psychical life alien to myself, if, as we have seen, bodies generally are only the symbols of sensations, all that remains is to become reconciled to solipsism, which, however, Cornelius does not venture to do.
It should be said that Mach does not consider Cornelius to be a pupil of his, but of Avenarius. This is not surprising, since there is very much in common between the views of Mach on one hand and Avenarius on the other, as Mach himself admits.  The question which Fichte described as the plurality of individuals is the major difficulty both for the philosophy of Avenarius and the philosophy of Mach and one which neither can cope with otherwise than by admitting the truth of materialism or landing in the impasse of solipsism. This must be obvious to every thinking person who takes the trouble to read, for instance, Avenarius’ The Human Concept of the World  of which a Russian translation has been published.
It is self-evident that only a follower of Poprishchin  could ‘combine’ solipsism with any other (not only the materialist) view of history.
The contemporary theory of development, of which our own explanation of history is a part, finds firm ground for itself only in materialism; and it is no wonder, therefore, that the founders of scientific socialism took materialism seriously, as Engels expressed it, applying it consistently in all the branches of knowledge which had hitherto been the strongholds of idealism.
And please note that it is not only scientific socialism which is closely linked with materialism. Utopian socialism, which liked to flirt with idealism and even with religion, must also be recognised as a legitimate offspring of materialism, as is clear from the first appendix to this pamphlet (Karl Marx on French Materialism of the Eighteenth Century): 
Just as Cartesian materialism passes into natural science proper, the other trend of French materialism leads directly to socialism and communism.
There is no need for any great penetration to see from the teaching of materialism on the original goodness and equal intellectual endowment of men, the omnipotence of experience, habit and education, and the influence of environment on man, the great significance of industry, the justification of enjoyment, etc, how necessarily materialism is connected with communism and socialism. If man draws all his knowledge, sensation, etc, from the world of the senses and the experience gained in it, then what has to be done is to arrange the empirical world in such a way that man experiences and becomes accustomed to what is truly human in it and that he becomes aware of himself as man. If correctly understood interest is the principle of all morality, man’s private interest must be made to coincide with the interest of humanity. If man is unfree in the materialistic sense, that is, is free not through the negative power to avoid this or that, but through the positive power to assert his true individuality, crime must not be punished in the individual, but the anti-social sources of crime must be destroyed, and each man must be given social scope for the vital manifestation of his being. If man is shaped by environment, his environment must be made human. If man is social by nature, he will develop his true nature only in society, and the power of his nature must be measured not by the power of the separate individual but by the power of society.
These and similar propositions are to be found almost literally even in the oldest French materialists. 
Marx then goes on to reveal the kinship of the various utopian schools of France and Britain with materialism.
However, those who are endeavouring to ‘combine’ Marxism with this or that variety of more or less consistent idealism pay not the slightest attention to all this. And it is unfortunate, the more so indeed that ‘there is no need for any great penetration’ to grasp the thorough inconsistency of all these attempts at combination.
But how should one understand materialism? Right to the present day people are still arguing a lot about it. Engels says:
Thus the question of the relation of thinking to being – the paramount question of the whole of philosophy – has, no less than all religion, its roots in the narrow-minded and ignorant notions of savagery. But this question could for the first time be put forward in its whole acuteness, could achieve its full significance, only after humanity in Europe had awakened from the long hibernation of the Christian Middle Ages. The question of the position of thinking in relation to being, a question which, by the way, had played a great part also in the scholasticism of the Middle Ages, the question: which is primary, spirit or nature? – that question, in relation to the church, was sharpened into this: Did God create the world or has the world been in existence eternally?
The answers which the philosophers gave to this question split them into two great camps. Those who asserted the primacy of spirit to nature and, therefore, in the last instance, assumed world creation in some form or other – and among the philosophers, Hegel, for example, this creation often becomes still more intricate and impossible than in Christianity – comprised the camp of idealism. The others, who regarded nature as primary, belong to the various schools of materialism.
These two expressions, idealism and materialism, originally signify nothing else but this; and here too they are not used in any other sense. What confusion arises when some other meaning is put into them will be seen below. 
Thus the most important distinguishing feature of materialism is that it does away with the dualism of spirit and matter, god and nature, and deems nature to be the basis of all those phenomena which the primitive hunting tribes could not explain without reference to the activity of souls, spirits. To the opponents of materialism, who for the most part have only the most absurd notions of it, it seems that Engels wrongly defined the essence of materialism and that, in fact, materialism reduces psychic phenomena to material phenomena. This is why they were greatly surprised when, in my dispute with Mr Bernstein, I listed Spinoza among the materialists. But for proof of the correctness of Engels’ definition of materialism, suffice it to quote some extracts from the writings of the eighteenth-century materialists.
Let us not go beyond the confines of nature (demeurons dans la nature) when we wish to apprehend natural phenomena [says the author of the celebrated work Le bon sens puisé dans la nature (Holbach]), and let us ignore causes that are too subtle to act upon our senses;  let us be convinced that by going beyond the confines of nature we shall never solve the problems nature places before us. 
Holbach expresses himself in exactly the same way in another, better known work, Système de la nature, which I shall not quote precisely because it is better known. I shall be content to indicate that the passage dealing with the question we are interested in will be found in Chapter 6 of Volume 2 of this work (page 146 of the London 1781 edition).
Helvétius hold the same point of view:
Man [he said] is the work of nature; he is in nature; he is governed by its laws; he cannot free himself from it; he cannot go outside it even in thought... For a being formed by nature, nothing exists outside the great whole of which he himself is a part... Beings supposed to be above nature and distinct from it are chimeras [and so forth]. 
True, there have been materialists who acknowledged the existence of God and regarded nature as his creation. One of these was Joseph Priestley.  But the celebrated naturalist’s faith was a simple theological appendage to his materialist teaching, the basic principle of which was the conception that man is the creation of nature and that ‘the corporeal and mental faculties inherent in the same substance, grow, ripen, and decay together’.  This substance is matter, as Priestley repeats more than once in this and others of his works. 
Feuerbach justly remarks that the substance which Spinoza refers to theologically as God, on closer examination (bei Lichte besehen), proves to be nature.  This is just as true as another of Feuerbach’s remarks: ‘The secret, the true meaning of Spinoza’s philosophy is Nature.’  This is precisely why Spinoza, in spite of the theological covering to his fundamental philosophical conception, must he considered a materialist. This was appreciated by Diderot who, as may be seen from his article ‘Spinosiste’, in Volume 15 of the Encyclopédie, counted himself and those who held similar views as modern Spinozists (spinosistes modernes). When ‘Marx’s critics’ uttered their unanimous gasp of surprise at the declaration I made in the course of my debate with Mr Bernstein that the materialism of Marx and Engels was a kind of Spinozism (eine Art Spinosismus), they were simply betraying their own amazing ignorance.  To be able to grasp this thought more easily, one should, firstly, remember that Marx and Engels passed through Feuerbach’s philosophy and, secondly, try to elucidate what exactly it is that distinguishes Feuerbach’s philosophy from Spinoza’s. Anyone who can understand the above will soon see that in his basic view on the relation of being to thinking, Feuerbach is Spinoza who has ceased to call nature god and has been through Hegel’s school.
Let us go on. If, as we have seen, Priestley taught that matter is capable of sensation and thought, it is clear from this that materialism in no way tries to reduce all psychical phenomena to the motion of matter, as its adversaries contend.  To the materialist, sensation and thought, consciousness, are the internal state of matter in motion. But none of the materialists who have left their mark on the history of philosophical thought has ever ‘reduced’ consciousness to motion, or explained one by the other. When the materialists maintained that there is no need to devise a special substance – the soul – to explain psychical phenomena, and that matter is capable of ‘sensation and thought’, this property of matter seemed to them just as basic and therefore inexplicable as motion. Thus, for example, La Mettrie, whose teaching is usually described as the most crude variety of materialism, stated categorically that he considered motion to be the same ‘mystery of nature’ as consciousness.  Besides, different materialists had different views of matter’s ability to possess consciousness. Some of them, for example, Priestley and, apparently, Holbach (who did not, however, express himself quite definitely) believed that consciousness arises in moving matter only in those cases where it is organised in a certain fashion. Others – Spinoza, La Mettrie, Diderot – thought that matter always possesses consciousness, although it only reaches a significant degree of intensity when organised in a certain way. The celebrated Haeckel is now known to hold this view. As to the general question of whether matter has the ability to ‘think’, hardly any conscientious naturalist would place himself in difficulty by answering it negatively. The ‘agnostic’ Huxley wrote in his book on Hume: ‘Surely no one who is cognisant of the facts of the case, nowadays, doubts that the roots of psychology lie in the physiology of the nervous system.’  This is exactly what the materialists say and Engels is perfectly correct in this pamphlet when he calls agnosticism simply shamefaced materialism. Contemporary psycho-physiology is thoroughly saturated with the spirit of materialism. True, some psycho-physiologists evade having to draw materialist conclusions by relying on the doctrine of concomitance of psychical and physical phenomena. But in this case, the stating of concomitance is but a means of discovering the causal connection of phenomena, as was expounded already by Alexander Bain. 
Now let us consider another aspect of the matter. The philosophy of Marx and Engels is not just a materialist philosophy. It is dialectical materialism. It is objected to this teaching, firstly, that dialectics will not stand criticism and, secondly, that materialism is incompatible with dialectics. Let us consider these objections.
The reader will no doubt remember that Mr Bernstein attributed what he called the errors of Marx and Engels to the harmful influence of dialectics. There is a formula in common logic: ‘yea – yea and nay – nay’. Dialectics transforms this into its direct opposite: ‘yea – nay and nay – yea’. Mr Bernstein did not like this latter ‘formula’ and declared that it could lead one into the most dangerous logical temptations and errors. And probably the great majority of so-called educated readers agreed with him, since the formula: ‘yea – nay and nay – yea’ evidently contradicts sharply the basic, fixed laws of thought. We shall have to examine this aspect of the matter here.
There are said to be three ‘basic laws of thought’: 1) the law of identity; 2) the law of contradiction; 3) the law of excluded middle.
The law of identity (principium identitatis) runs: A is A (omne subjectum est predicatum sui) or, otherwise, A equals A.
The law of contradiction – A is not non-A – is only the negative form of the first law.
According to the law of excluded middle (principium exclusi tertii) two contradictory propositions excluding one another cannot both be wrong. Indeed, A is either B or non-B; the truth of one of the propositions unerringly signifies the falsity of the other and vice versa. There is not and cannot be a middle here.
Überweg remarks that the law of contradiction and the law of excluded middle can be combined in the following rule of logic: each fully defined question – always understood in the same fully defined sense – of whether a particular predicate belongs to a particular subject must be answered either yea or nay and cannot be answered both yea and nay. 
It is difficult to raise any objection to the truth of this rule. But if it is true, then the formula ‘yea – nay and nay – yea’ seems altogether unsound; we can only ridicule it like Mr Bernstein, and throw up our hands in dismay as to why such undoubtedly profound thinkers as Heraclitus, Hegel and Marx could find it more satisfactory than the formula ‘yea – yea and nay – nay’ which has a firm basis in the above-mentioned basic laws of thought.
This conclusion, a fatal one for dialectics, is apparently irrefutable. But before we accept it, let us consider another aspect of the matter.
The basis of all natural phenomena is matter in motion.  But what is motion? It is an obvious contradiction. If you were asked: is a body in motion in a given place at a given time, even with the best intentions in the world you would not be able to reply according to Überweg’s rule, that is, the formula ‘yea – yea and nay – nay’. A body in motion is in a given place and at the same time is not in it.  It can be judged only by the formula ‘yea – nay and nay – yea.’ It is therefore an irrefutable witness in favour of the ‘logic of contradiction’, and he who refuses to be reconciled to this logic must declare along with the ancient Zeno that motion is no more than an illusion of the senses. This is evidently not understood by our compatriot Mr NG, who is also a very firm opponent of dialectics but, unfortunately, not a very serious one. He says that if a body in motion, with all its parts:
... is in one place, its simultaneous presence in another place is a manifest appearance out of nothing, for whence could it get to another place? From the first place? But the body has still not left the first place.
But, he continues, if we assume that the body with not all its parts is in a given place at a given time, do not the different parts of a body which is at rest also occupy different places in space? 
Very good, though very old. However, what do Mr NG’s arguments prove? They prove that motion is impossible. Splendid; here, too, we shall not argue, but we remind Mr NG of Aristotle’s remark which is daily and invariably justified by natural science, that by negating motion we make all study of nature impossible.  Was that what Mr NG wanted? Was that the wish of the ‘literary monthly’ which printed his profound work? If neither one nor the other wished to negate motion, they should have understood that, by warming up the ‘aporia’ of Zeno they left themselves with no alternative but to recognise that motion is contradiction in action, that is to say, to admit precisely what Mr NG wanted to refute. Well, some ‘critics’!
However, we ask all those who do not deny motion: what should we think of that ‘basic law’ of thought which contradicts the basic fact of being? Should we not approach it... with some circumspection?
It looks as if we are now faced with an unexpected choice: either to acknowledge the ‘basic laws’ of formal logic and negate motion, or, on the contrary, to acknowledge motion and negate those laws. It is a rather unpleasant choice. Is there no way round it?
Matter in motion lies at the basis of all natural phenomena. Motion is contradiction. It must be judged dialectically, that is to say, as Mr Bernstein would put, it, by the formula: ‘yea – nay and nay – yea’. Therefore we must admit that so long as we are speaking about this basis of all phenomena, we are in the domain of ‘the logic of contradiction’. But the molecules of matter in motion, joining one with the other, form certain combinations, things, objects. Such combinations are distinguished by the greater or lesser degree of their stability, exist for a more or less prolonged period, and then pass away, with others taking their place: only the motion of matter is eternal, while matter itself is the indestructible substance. But once a certain temporary combination of matter has taken place as the result of its eternal motion, and as long as that combination has not yet passed away in consequence of this motion, we have to resolve the question of its existence in the affirmative. So that if someone points at the planet Venus and asks if it exists, we shall say without hesitation: yes. And if we are then asked: do witches exist, we should just as resolutely reply: no. What does this mean? It means that when we are speaking about individual objects we are obliged to judge them according to Überweg’s above-mentioned rule and generally be guided by the ‘basic laws’ of thought. This domain is governed by Mr Bernstein’s favourite formula: ‘yea – yea and nay – nay.’ 
Nonetheless, even here the powers of that worthy formula are not unlimited. A definite answer must be given to the question of the existence of an object already in being. But if this object is as yet only coming into being, one might sometimes be justified in hesitating to answer. When half of a man’s hair has fallen out we may say he is bald. But just try to determine exactly at what point falling hair becomes baldness.
Every definite question as to whether a particular property is part of a particular object must be answered either yea or nay. That is indisputable. But how should one reply where the object is changing, when it is already shedding the particular property or is still only acquiring it? Needless to say, a definite answer is demanded here too; but the point is that it will be definite only if it is based on the formula ‘yea – nay and nay – yea’. It is impossible to answer the question according to the Überweg formula: ‘either yea or nay’.
Of course, it may be objected that the property being shed has not yet ceased to exist, and the property being acquired already exists, and therefore it is possible and obligatory to give a definite answer according to the formula ‘either yea or nay’, even when the object is in a state of change. However, this is wrong. The young man on whose chin ‘down’ has appeared is certainly beginning to grow a beard, but this still does not give us the right to call him bearded. Down on the chin is not yet a beard, although it is changing into a beard. To become qualitative a change must reach a certain quantitative limit. Whoever forgets this loses precisely the power to express definite judgements on the properties of objects.
‘Everything is fluid, everything changes’, said the ancient Ephesian thinker. The combinations we call objects are in a state of constant – more or less rapid – change. In so far as the combinations concerned remain particular combinations, we must judge them by the formula ‘yea – yea and nay – nay’. But in so far as they change and cease to exist as such we must turn to the logic of contradiction; we must declare, while risking the disapproval of Messrs Bernstein, NG and others of their metaphysical brethren: ‘Both yea and nay; they exist and they do not exist.’
Just as rest is a particular case of motion, so thought, according to the rules of formal logic (conforming to the ‘basic laws’ of thought) is a particular case of dialectical thought.
It was said of Cratylus, one of Plato’s teachers, that he did not agree even with Heraclitus who had declared: ‘We cannot enter the same stream twice.’ Cratylus asserted that we cannot do so even once; while we enter the stream it is already changing, becoming another stream. In such judgements, it is as though the element of determinate being is being replaced by the element of becoming.  This is a misuse of dialectics, not a correct application of the dialectical method. Hegel remarked: ‘Das Etwas ist die erste Negation der Negation.’ (‘The Something is the first negation of the negation.’) 
Those of our critics who have not completely lost touch with philosophical literature, like to cite Trendelenburg who is supposed to have shattered completely all the arguments in favour of dialectics. But these gentlemen have evidently read Trendelenburg badly, if they have read him at all. They have forgotten – if it was ever known to them, which I strongly doubt – the following trifle. Trendelenburg acknowledges that the principium contradictionis is applicable not to motion but only to those objects that are created by motion.  He is right. But motion does not only create objects. As we have said, it constantly changes them. That is why the logic of motion (‘the logic of contradiction’) never loses its sovereignty over the objects created by motion, so that while paying due tribute to the ‘basic laws’ of formal logic we must remember that their significance is limited to the extent that they do not hinder us from also giving proper recognition to dialectics. This is how the matter actually stood with Trendelenburg, although he did not draw the appropriate logical conclusions from the principle that he himself stated – an extremely important one for the scientific theory of cognition.
In passing, we shall add here that there are very many useful remarks scattered throughout Trendelenburg’s Logische Untersuchungen which speak not against us but in our favour. This may seem strange, but it can be very simply explained by the very simple circumstance that Trendelenburg, strictly speaking, was combating idealist dialectics. For instance, he diagnosed the weakness of dialectics as that it ‘asserts the spontaneous motion of pure thought which is at the same time the self-generation of being’ [’behauptet... eine Selbstbewegung des reinen Gedankens, die zugleich die Selbsterzeugung des Seins ist’]. 
This is indeed a very great mistake. But who can fail to realise that this weakness is peculiar only to idealist dialectics? Who does not know that when Marx wanted to place dialectics ‘the right way up’ he began by correcting this fundamental error which had grown from its old idealist roots? Another example. Trendelenburg says that to Hegel motion is indeed the basis of that logic which apparently does not require any presuppositions to justify it.  This again is perfectly true; but once again it is an argument in favour of materialist dialectics. A third and the most interesting example. According to Trendelenburg, it is wrong to think that to Hegel nature was only applied logic. Just the contrary. Hegel’s logic is by no means the result of pure thought; it was created by preliminary abstraction from nature (eine antizipierte Abstraktion der Natur). In Hegel’s dialectics almost everything is drawn from experience, and if experience could take from dialectics all that dialectics has borrowed from experience, dialectics would indeed be left with a beggar’s staff.  That is so, exactly so! But then that is just what Hegel’s pupils said when they rebelled against his idealism and went over to the camp of materialism.
I could adduce many more similar examples but that would only distract me from my subject. I simply wished to show our critics that it would probably have been better for them not to have cited Trendelenburg at all in their fight with us.
To proceed. I said that motion is contradiction in action and that therefore the ‘basic laws’ of formal logic are inapplicable to it. In order that this proposition should not give rise to misunderstandings, a qualification is needed. When we are confronted with the question of the transition from one type of motion to another – say, from mechanical motion to heat – we also have to reason in accordance with Überweg’s basic rule. This type of motion is either heat or mechanical motion or, etc. That is clear. But if this is so, the basic laws of formal logic are applicable within certain limits also to motion. It follows once more that dialectics does not abrogate formal logic, but simply deprives its laws of the absolute significance attached to them by the metaphysicians.
If the reader has followed attentively what has been said above, he should have no difficulty in understanding how little ‘value’ there is in the now oft-repeated idea that dialectics is irreconcilable with materialism.  On the contrary, the foundation of our dialectics is the materialist conception of nature. Our dialectics is based on materialism and would collapse were materialism to collapse. And vice versa: the materialist theory of cognition would be incomplete, one-sided – more than that, it would be impossible without dialectics.
With Hegel, dialectics coincides with metaphysics; with us dialectics rests upon the study of nature.
With Hegel, the demiurgos of the real world, to use one of Marx’s expressions, is the Absolute Idea. For us, the absolute idea is only an abstraction from motion which gives rise to all combinations and conditions of matter.
With Hegel, thought moves forward as a consequence of the revelation and solution of the contradictions within conceptions. According to our – materialist – teaching, the contradictions within conceptions are only the reflections, translated into the language of thought, of the contradictions within phenomena due to the contradictory nature of their common basis, that is to say, motion.
With Hegel, the course of things is determined by the course of ideas. With us the course of ideas is explained by the course of things, the course of thought by the course of life.
Materialism puts dialectics ‘the right way up’ and thereby removes the mystical veil in which Hegel had it wrapped. By the very fact of this it brings to light the revolutionary character of dialectics.
In its mystified form, dialectic became the fashion in Germany, because it seemed to transfigure and to glorify the existing state of things. In its rational form it is a scandal and abomination to bourgeoisdom and its doctrinaire professors, because it includes in its comprehension and affirmative recognition of the existing state of things, at the same time also, the recognition of the negation of that state, of its inevitable breaking up; because it regards every historically developed [to be exact: which has emerged, become – gewordene – GP] social form as in fluid movement, and therefore takes into account its transient nature not less than its momentary existence; because it lets nothing impose upon it, and is in its essence critical and revolutionary. 
That materialist dialectics is an abomination to the through and through reactionary bourgeoisie is in the nature of things; but that even people who sincerely sympathise with revolutionary socialism sometimes turn their backs on dialectics is both ridiculous and extremely sad; it is the height of nonsense.
After all I have said, it seems to me that I can afford to shrug my shoulders at the astonishing invention of Mr NG who attributes to us the principle of a ‘dual organisation of mind’, a principle which, according to him, is the ‘premise’ which can alone make our ‘dialectical logic the least bit plausible’.  Well, well! Our implausible critic has indeed found a mare’s nest!
Now we must turn our attention to something else. We know already that Überweg was right – and to what extent he was right – in demanding that logically thinking people give definite answers to definite questions as to whether a particular property belongs to a particular object. But suppose we are dealing, not with a simple object, but with a complex one which unites in itself directly opposing phenomena possessing directly opposing properties. Is Überweg’s rule applicable to such an object? No, Überweg himself, who is just as decided an opponent of Hegel’s dialectics as Trendelenburg, finds that this has to be considered in accordance with another rule, namely, the combination of opposites (principium coincidentiae oppositorum). But the vast majority of the phenomena that are the concern of natural science and social science belong to the list of ‘objects’ of exactly this type: the most directly opposed phenomena are combined in the most simple clot of protoplasm, in the life of the most undeveloped society. Consequently, the dialectical method must occupy an important place in natural science and social science. From the moment such a place was allocated to the dialectical method in these sciences they have made enormous advances.
Would you like to know, reader, how dialectics won its spurs in biology? Recall the disputes about what constituted species which were aroused by the appearance of the theory of transformism. Darwin and his supporters were of the opinion that the various species of one and the same genus of animals or plants were none other than the variously developed descendants of one and the same original form. Besides this, in accordance with the theory of development, all genera of one and the same succession also stem from one common form and the same must be said of all successions of one and the same class. Darwin’s opponents, on the other hand, took the contrary view that all animal and vegetable species are completely independent of one another and that only individuals belonging to one and the same species come from a common form. The same conception of species had already been expressed by Linnaeus who said: ‘There are as many species as were originally created by the Supreme Being.’ This is a purely metaphysical view, since metaphysics perceives that things and ideas ‘are isolated, are to be considered one after the other and apart from each other, are objects of investigation fixed, rigid, given once for all’ (Engels). Dialectics, on the other hand, comprehends things and ideas, in Engels’ own words, ‘in their essential connection, concatenation, motion, origin and ending’.  This conception has been an integral part of biology since Darwin’s time and will always remain so no matter what corrections are introduced into the theory of transformism by the further development of science.
To comprehend the great significance of dialectics in sociology, it is sufficient to recall how socialism was transformed from a utopia to a science.
The utopian socialists held the abstract point of view of human nature and judged social phenomena by the formula ‘yea – yea and nay – nay’. Property either conforms or does not conform to human nature; a monogamic family either conforms or does not conform to human nature, and so on and so forth. Since human nature was supposed to be unchangeable, socialists had the right to expect that among all the possible social systems there would be one which corresponded to human nature more than all the others. Hence arose the endeavours to find this best system, that is to say, one that conformed most to human nature. Each founder of a school thought he had discovered such a system; each proposed his own utopia. Marx introduced the dialectical method into socialism and thus converted it into a science, dealing a mortal blow at utopianism. Marx does not appeal to human nature; he knows of no social institutions that either conform or do not conform to human nature. In his Poverty of Philosophy we find the following remarkable and characteristic rebuke to Proudhon: ‘M Proudhon does not know that all history is nothing but a continuous transformation of human nature.’  In Capital, Marx says: ‘By thus acting on the external world and changing it, he [man] at the same time changes his own nature.’  This is the dialectical point of view, shedding quite new light on questions of social life. Take the issue of private property. The Utopians wrote and argued much among themselves and with the economists about whether private property must exist, that is to say, whether it conforms to human nature. Marx put the question on a concrete basis. He stated that the forms of property and property relations are conditioned by the development of the productive forces. To one stage of the development of these forces corresponds one form; to another stage another form – but there is not and cannot be an absolute decision since everything is fluid, everything changes; ‘wisdom becomes madness, bliss – torment’. 
Hegel said: ‘Contradiction leads forward.’ Science finds splendid confirmation of this dialectical view in the class struggle, without consideration of which nothing can be understood of the development of the social and spiritual life of class society.
Why then is the ‘logic of contradiction’ which, as we have seen, is the reflection of the eternal process of motion in the human mind, called dialectics? To avoid a protracted discussion on the matter, I shall quote from Cuno Fischer:
Human life may be compared with dialogue in this respect, that with age and experience our views of people and things are gradually transformed, like the opinions of the disputants in the course of a debate which is fruitful and rich in ideas. It is this spontaneous and necessary transformation of our views of life and the world which actually constitutes experience... That is why Hegel, in comparing the course of development of consciousness with the course of philosophical debate, called it by the name dialectic, or dialectical motion. This expression had already been adopted by Plato, Aristotle and Kant in a sense important and distinctive to each of them, but in no system did it receive such a comprehensive significance as in Hegel’s. 
There are many, too, who do not understand either why views such as those of Linnaeus on animal and vegetable species, for example, are described as metaphysical. Apparently these words – metaphysics, metaphysical – mean something quite different. We shall try to explain this as well.
What is metaphysics? What is its subject?
Its subject is the so-called unconditional (the absolute). And what is the main distinctive feature of the unconditional? Immutability. This is not surprising, since the unconditional is not dependent on changing circumstances (conditions) of time and place, which alter the ultimate objects accessible to us. That is why it does not change. What then is the most distinctive feature of those concepts which have been and are used by the people described in the language of dialectics as metaphysicians? This also is their immutability, as we noted in the example of Linnaeus’ teaching on species. In their own way, these concepts are unconditional, too. So their nature is identical with that of the unconditional, the subject matter of metaphysics. That is why Hegel described as metaphysical all those concepts which are elaborated (to use his own words) by reason, that is to say, which are accepted as immutable and are isolated from one another by an impassable gulf. The late Nikolai Mikhailovsky thought that Engels was the first writer to use the terms ‘metaphysical’ and ‘dialectical’ in the sense we now know. But this is wrong. These terms were originally used by Hegel. 
I shall probably be told that Hegel had his own metaphysics. I do not deny this: he had. But his metaphysics merged with dialectics, and in dialectics there is nothing immutable, everything is in motion, everything changes.
When I sat down to write this preface, I had intended to say something about Mr Berdyaev’s review in the journal Voprosy Zhizni  of Engels’ Anti-Dühring, a Russian translation of which has recently been published. Now I realise I cannot carry out this intention for want of space. I cannot say that I am very sorry about it; Mr Berdyaev’s review will convince only those readers who are already convinced and whom, therefore, there was no need to convince. Mr Berdyaev’s own opinions, however, do not deserve attention. Spinoza said of Bacon that he did not prove his opinions; he only described them. The same might be said of Berdyaev, if his method of presenting his thoughts would not be better described by the word decree. But when such a thinker as Bacon describes, or, for that matter, decrees, his views, much exceptionally valuable material will be found in his descriptions and decrees. And when such a muddle-head as Mr Berdyaev takes to issuing decrees, absolutely nothing instructive will come of them.
But wait... It is clear from Mr Berdyaev’s decrees where, according to his practical reason, the main weakness of Engels’ world-outlook lies. It lies in this, that it impedes the transformation of social democracy into bourgeois democracy. And that is very interesting; so we shall put it on record.
Chexbres sur Vevey
4 July 1905
Notes are by Plekhanov, except those by the Moscow editors of this edition of the work, which are noted ‘Editor’.
1. The reference is to the ‘legal Marxists’ – liberal bourgeois, who in the 1890s came out in the Russian legal press under the banner of Marxism. ‘Legal Marxism’ by its character was akin to Bernsteinianism – Editor.
2. See Georgi Plekhanov, Selected Philosophical Works, Volume 1 (Moscow, 1974), pp.449-61 – Editor.
3. Die Analyse der Empfindungen (fourth edition), pp.282-83.
4. See, in the above-mentioned book, the chapter headed ‘Mein Verhältnis zu R Avenarius und anderen Forschern’, p.38.
5. One German writer remarks that for empirio-criticism experience is only an object of investigation and not a means of knowledge. If this is right, there is no point in opposing empirio-criticism to materialism, and to argue whether it is destined to replace materialism is a sheer waste of time.
6. Poprishchin: a character from Gogol’s story Notes of a Madman – Editor.
7. The supplement mentioned is an excerpt from Marx and Engels’ The Holy Family, Chapter 6, item ‘Critical Battle Against French Materialism’ – Editor.
8. Karl Marx and Frederick Engels, Collected Works, Volume 4 (Moscow, 1975), pp.130-31 – Editor.
9. Karl Marx and Frederick Engels, Selected Works, Volume 3 (Moscow, 1975), p.346 – Editor.
10. Note that Holbach calls everything that acts on our senses matter.
11. I am quoting from the Paris edition of ‘the first year of the Republic’.
12. ‘Le vrai sens du système de la nature’, Chapter 1 of De la Nature.
13. See his Disquisitions Relating to Matter and Spirit, in Volume 1 of the Birmingham edition, 1782. There God is declared to be ‘our Maker’ (p.139), the ‘All in all’ (p.143), and so on.
14. Ibid, p.69.
15. ‘Matter being capable of the property of sensation or thought’ (The History of the Philosophical Doctrine Concerning the Origin of the Soul... in the first volume of the same edition of his Works, p.400).
16. Werke, Volume 4, p.380.
17. Ibid, p.391.
18. I was asked by objection: what does a kind of Spinozism mean. This is easy to answer: in Marx and Engels as well as in Diderot, Spinozism was freed of its theological exterior. That is all.
19. See, for example, Lasswitz, Die Lehre Kant’s von der Idealilät des Raumes und der Zeit (Berlin, 1883), p.9.
20. Oeuvres philosophiques de Monsieur de La-Mettrie, Volume 1 (Amsterdam, 1764), pp.69, 73.
21. See p.181 of the French translation of this book [TH Huxley, Thomas Hume (London, 1879), p.80].
22. Mind and Body, Russian translation of the sixth English edition (Kiev, 1884), pp.24-25.
23. System der Logik (Bonn, 1874), p.219.
24. I am speaking of the objective side of phenomena. ‘Une volition est, pour le cerveau un mouvement d’un certain système de fibres. Dans l’âme c’est ce qu’elle éprouve en conséquence du mouvement des fibres...’ (Robinet, De la Nature, Volume 1, Chapter 23, part 4). [’For the brain, volition is the movement of a certain system of fibres; in the soul it is what it feels as a result of the movement of the fibres.’] Cf Feuerbach’s: ‘Was für mich oder subjectiv ein rein geistiger... Akt, ist an sich oder objectiv ein materieller, sinnlicher.’ (Werke, Volume 2, p.350). [’What for me or subjectively is a purely spiritual act..., is in itself or objectively a material sentient act.’]
25. Even the most decided opponents of the dialectical method were compelled to recognise this. ‘Die Bewegung’, says A Trendelenburg, ‘die vermöge ihres Begriffs an demselben Punkte zugleich ist und nicht ist.’ (Logische Untersuchungen, Volume 1 (Leipzig, 1870), p.189) (‘Motion, which by virtue of its own concept is and is not simultaneously at one and the same point.’] It is almost superfluous to remark here, as Überweg has already done, that Trendelenburg should have said ‘matter in motion’ rather than ‘motion’.
26. ‘Materialism and Dialectical Logic’, Russkoye Bogatstvo, July 1889, pp.94, 96. [Russkoye Bogatstvo (Russian Wealth): a monthly magazine published in St Petersburg from 1876 to 1918. From the early 1890s it became an organ of the liberal Narodniks under the editorship of NK Mikhailovsky. The journal distorted and falsified Marxism and came out against the Social-Democrats and in defence of revisionism – Editor.]
27. Metaphysics, I, VII, 59.
28. Historical judgements of the kind, as indicated by Überweg (in Logik, p.196): was Plato born in the year 429, or 428, or 427 BC must also be answered according to this formula. This reminds me of the amusing reply made by a young Russian revolutionary who arrived in Geneva, if I am not mistaken, in 1882. He had to give the police some information about himself. ‘Where were you born?’, asked the friend who was arranging the matter, the late NI Zhukovsky. ‘In various gubernias’, replied the overcautious ‘conspirator’ evasively. Zhukovsky flared up and exclaimed: ‘Nobody will believe that, my friend!’ And here even the most zealous advocate of the dialectical method would agree with him.
29. I retain here the terms used by N Lossky in his translation of the book on Hegel by Cuno Fischer: Dasein – determinate being; Werden – becoming.
30. Werke, Volume 3, p.114.
31. Logische Untersuchungen, Volume 2 (third edition, Leipzig, 1870), p.175.
32. Logische Untersuchungen, Volume 1 (third edition, Leipzig, 1870), p.36.
33. Ibid, p.42.
34. Ibid, pp.78-79.
35. ‘It seems to us that materialism and dialectical logic are elements which may be considered incompatible philosophically’, said the profound Mr NG (Russkoye Bogatstvo, June 1889, p.59).
36. See Preface to the Second German edition of Capital. [Karl Marx, Capital, Volume 1 (Moscow, 1974), p.29 – Editor.]
37. Russkoye Bogatstvo, June 1889, p.64. Parmenides in his polemic with Heraclitus’ pupils called them two-headed philosophers to whom many things appear in dual form: as existing and as non-existing. Mr NG now advances as a philosophical principle that which for Parmenides was a display of polemical guile. What progress we are making, ‘God help us’, in the ‘first questions’ of philosophy!
38. Frederick Engels, Anti-Dühring (Moscow, 1975), pp.29-30 – Editor.
39. Misère de la Philosophie (new edition, Paris, 1890), p.204. [Karl Marx and Frederick Engels, Collected Works, Volume 6 (Moscow, 1976), p.192 – Editor.]
40. Das Kapital, third edition, pp.155-56. [Karl Marx, Capital, Volume 1 (Moscow, 1974), p.173 – Editor.]
41. Goethe, Faust, Part One, Scene Four – Editor.
42. Hegel: His Life and Works, Half Volume 1 (translated by NO Lossky, St Petersburg), p.308.
43. See p.81 of the First Volume of his Great Encyclopaedia. [Plekhanov is referring here to Hegel’s Encyklopädie der philosophischen Wissenschaften in Grundrisse (Encyclopaedia of Philosophical Sciences) – Editor.]
44. See N Berdyaev, ‘A Diary of a Publicist: Catechism of Marxism’, Voprosy Zhizni [Life’s Problems], no 2, 1915 – Editor.