George Plekhanov

Dialectic and Logic

Source: G. Plekhanov. Marxist Library Volume I. Fundamental Problems of Marxism. Dialectics and Logic;
Translated: by Eden and Cedar Paul, edited by D. Riazanov;
Published: by International Publishers. New York. 1928;
Transcribed: by Marc Lispi.

The philosophy of Marx and Engels is not only a materialist philosophy, it is dialectical materialism. Two objections are, however, raised against this doctrine. We are told, first of all, that dialectic itself is not proof against criticism; and, secondly, that materialism is incompatible with dialectic. Let us examine these objections.

The reader will probably remember how Bernstein explained what he termed the “errors” of Marx and Engels. They were due, he said, to the disastrous influence of dialectic. Customary logic holds fast to the formula: “Yes is yes, and no is no”; whereas dialectic has a formula of a diametrically opposite kind: “Yes is no, and no is yes.” Detesting this latter formula, Bernstein declares that it leads us into temptation and involves us in the most dangerous errors.

Probably most readers who pass by the name of “educated” will agree with Bernstein, seeing that, on the face of it, the formula “Yes is no, and no is yes” is in flagrant contradiction with the fundamental and immutable laws of thought. That is the aspect of the question we have now to examine.

The fundamental laws of logic are three in number:

(I) The law of identity;

(2) The law of contradiction;

(3) The law of the excluded middle.

The law of identity (principium identitatis) declares: A is A (omne subjectum est praedicatum sui), or A=A.

The law of contradiction, A is not not-A, is nothing more than the negative form of the first law.

According to the law of the excluded middle (principium exclusi tertii), two contradictory propositions, mutually exclusive, cannot both of them be true. In fact, either A is B, or else A is not B. If one of these propositions is true, the other is necessarily false; and conversely. There is not, and cannot be, any middle course here.

Ueberweg points out that the law of contradiction and the law of the excluded middle can be unified in the following logical rule: To every definite question, understood in a definite sense, as to whether a given characteristic attaches to a given object, we must reply either yes or no; we cannot answer yes and no.

It is certainly hard to raise any objection to this. But if the statement is true, that implies that the formula “Yes is no, and no is yes” must be erroneous. Nothing will be left for us, then, but to laugh, like Bernstein, and to raise our hands to heaven, when we see that thinkers as profound as Heraclitus, Hegel and Marx have found it more satisfying than the formula “Yes is yes, and no is no,” a formula solidly based upon the three fundamental laws of thought stated above.

This conclusion, fatal to dialectic, seems irrefutable. But, before we accept it, let’s examine the matter more closely.

The movement of matter underlies all the phenomena of nature. But what is movement? It is an obvious contradiction. Should any one ask you whether a body in motion is at a particular spot at a particular time, you will be unable, with the best will in the world, to answer In accordance with Ueberweg’s rule, that is to say in accordance with the formula, “Yes is yes, and no is no.” A body in motion is at a given point, and at the same time it is not there. We can only consider it in accordance with the formula “Yes is no, and no is yes.” This moving body thus presents itself as an irrefutable argument in favor of the “logic of contradiction”; and one who is unwilling to accept this logic will be forced to proclaim, with Zeno, that motion is merely an illusion of the senses.

But of all those who do not deny motion we shall ask: “What are we to think of this fundamental law of thought which conflicts with the fundamental fact of being? Must we not treat it with some circumspection?”

We seem to be between the horns of a dilemma. Either we must accept the fundamental laws of formal logic and deny motion; or else we must admit motion and deny these laws. The dilemma is certainly a disagreeable one. Let us see if there is no way of escaping it.

The movement of matter underlies all the phenomena of nature. But motion is a contradiction. We must consider the question dialectically, that is to say, as Bernstein would phrase it, in accordance with the formula “Yes is no, and no is yes.” Hence, we are compelled to admit that as concerns this basis of all phenomena we are in the domain of the “logic of contradiction.” But the molecules of matter in motion becoming conjoined one with another, form certain combinations; things, objects. Such combinations are distinguished by more or less marked solidity; they exist for a longer or shorter time, and then disappear, to be replaced by others. The only thing which is eternal is the movement of matter, matter itself, indestructible substance. But as soon as a particular temporary combination of matter has come into existence as a result of the eternal movement of matter, and as long as it has not yet disappeared owing to this same movement, the question of its existence must necessarily be solved in a positive sense. That is why, if anyone points out to us the planet of Venus and asks us “Does this planet exist?” we shall answer, unhesitatingly, “Yes.” But if anyone asks us whether witches exist, we shall answer, no less unhesitatingly, “No.” What does this mean? It means that when we are concerned with distinct objects we must, in our judgments about them, follow the above-mentioned rule of Ueberweg; and must, in general, conform to the fundamental laws of thought. In that domain there prevails the formula agreeable to Bernstein, “Yes is yes, and no is no.”

Even there, however, the realm of this respectable formula is not unrestricted. When we are asked a question as to the reality of an object which already exists, we must give a positive answer. But when an object is as yet only in course of becoming, we may often have a good reason for hesitating as to our reply. When we see a man who has lost most of the hair from his cranium, we say that he is bald. But how are we to determine at what precise moment the loss of the hair of the head makes a man bald?

To every definite question as to whether an object has this characteristic or that, we must respond with a yes or a no. As to that there can be no doubt whatever. But how are we to answer when an object is undergoing a change, when it is in the act of losing a given characteristic or is only in course of acquiring it? A definite answer should, of course, be the rule in these cases likewise. But the answer will not be a definite one unless it is couched in accordance with the formula “Yes is no, and no is yes”; for it will be impossible to answer in accordance with the formula “Either yes or no,” as recommended by Ueberweg.

The objection can, of course, be made that the characteristic which the object is in course of losing has not yet ceased to exist and that the one which it is in course of acquiring already exists, so that an answer couched in accordance with the formula “Either yes, or no” is possible, indeed obligatory, even when the object with which we have to do is undergoing change. But such a contention is erroneous. A youth on whose chin down is beginning to sprout is certainly growing a beard, but we cannot for that reason speak of him as bearded. Down on the chin is not a beard, although it gradually changes into a beard. If the change is to become qualitative, it must reach a quantitative limit. One who forgets this is unable to express a definite opinion concerning the qualities of objects.

“Everything is in a flux, everything changes,” said of old, the philosopher of Ephesus. The combinations which we speak of as objects are permanently in a state of more or less rapid change. In proportion as such combinations remain the same combinations, we can judge them in accordance with the formula “Yes is yes, and no is no.” But in proportion as they change to a degree in which they cease to exist as formerly, we must appeal to the logic of contradiction; we must, even at the risk of offending Bernstein and the whole tribe of metaphysicians, say “Yes and no, they exist and they do not exist.”

Just as inertia is a special case of movement, so thought in conformity with the rules of formal logic (in conformity with the fundamental laws of thought) is a special case of dialectical thought. It is recorded of Cratylus, one of Plato’s disciples, that he was not in agreement with Heraclitus, who had said: “We cannot go down the same river twice.” Cratylus insisted that we could not do it even once, seeing that, while we were going down the river, it, was changing, was becoming another river. In the case of such judgments, the factor which constitutes the extant being is, so to say, over-ruled by the factor of becoming. But this is to misuse dialectic and not to make a proper use of it. Hegel remarks: “The something’ is the first negation of negation.”

Those of our critics who are not completely ignorant of philosophical literature are fond of referring to Trendelenburg, who is said to have refuted all the arguments in favor of dialectic. But these gentlemen, obviously, have misread Trendelenburg, if they have read him at all. They have utterly forgotten (if they ever knew, which I doubt) one little matter. Trendelenburg declared that the law of contradiction is applicable, not to motion, but only to the objects created thereby. That is sound. But motion does not merely create objects. As I have already said, it is constantly modifying them. That is why the logic of movement (the “logic of contradiction”) never forfeits its rights over the objects created by motion. That is why, moreover, even while we pay to the fundamental laws of formal logic the homage which is their due, we must remember that these laws are only valid within certain limits, within limits which leave us free to pay homage also to dialectic. It is thus that the law was really formulated by Trendelenburg, although he himself did not draw all the conclusions derivable from the principle he formulated – a principle of outstanding importance to the theory of cognition.

Let me add, in passing, that Trendelenburg’s Logische Untersuchungen contain a number of sound observations which do not tell against my view but in favor of It. This may seem strange, but can be explained very simply by the simple fact that Trendelenburg was really attacking idealist dialectic. Thus he saw the defeat of dialectic in so far as it affirms a movement inherent in and proper to the pure idea, a movement which is an autocreation of being. Certainly such affirmation involves a profound error. But who does not know that the fallacy attaches exclusively to idealist dialectic? Who does not know that when Marx set to work in order to put dialectic “on its feet,” whereas it had been standing on its head, he began by correcting this primary error, which was the outcome of the old idealist foundation? Here is another instance. Trendelenburg says that as an actual fact, in Hegel’s system, motion is the foundation of logic (which, it seems, does not require any premises upon which to base itself). This statement is also correct, but is once more an argument in favour of materialist dialectic. Now for a third example, the most interesting one of them all. Trendelenburg tells us it is wrong to imagine that, according to Hegel, nature is nothing more than applied logic. On the contrary, the logic of Hegel is nowise a creation of the pure idea; it is the outcome of an anticipatory abstraction from nature: In Hegel’s dialectic, almost everything has been derived from experience; and if experience were to deprive dialectic of all that experience has lent, dialectic would be poor indeed. Perfectly true! But this is exactly what was said by those disciples of Hegel who rose in revolt against their master’s idealism and went over to the materialist camp.

I could give plenty more examples, but they would take me away from my subject. All I wanted was to show our critics that, in their campaign against us, they would do well to avoid calling in the aid of Trendelenburg.

To continue: I have said that motion is a contradiction in action; and that, consequently, the fundamental laws of formal logic cannot be applied to it. I must explain this proposition lest it should be misunderstood. When we have to do with the passage from one kind of movement to another (let us say, with the passage from mechanical movement to heat), we must also reason in accordance with Ueberweg’s fundamental rule. We must say: “This kind of motion is either heat, or else mechanical movement, or else...” and so on. That is obvious. But if so, it signifies that the fundamental laws of formal logic are, within certain limits, applicable also to motion. The inference, once more, is that dialectic does not suppress formal logic, but merely deprives the laws of formal logic of the absolute value which metaphysicians have ascribed to them.

If the reader has paid careful attention to what was said above, he will have no difficulty in understanding how worthless is the contention so often put forward that dialectic is incompatible with materialism. On the contrary, our dialectic is based upon the materialist conception of nature. If the materialist conception of nature were to crumble into ruins, our dialectic would crumble with it. Conversely, without dialectic, the materialist theory of cognition is incomplete, one-sided; nay more, it is impossible.

In Hegel’s system, dialectic coincides with metaphysics. For us, dialectic is buttressed upon the doctrine of nature.

In Hegel’s system, the demiurge [creator] of reality (to use Marx’s phrase) is the absolute idea. For us, the absolute idea is only an abstraction from the motion by which all the combinations and all the states of matter are produced.

According to Hegel, thought progresses thanks to the discovery and the solution of contradictions contained in concepts. According to our materialist doctrine, the contradictions contained in concepts are only the reflection, the translation into the language of thought, of contradictions which exist in phenomena owing to the contradictory nature of their common foundation, namely movement.

According to Hegel. the march of things is determined by the march of ideas; according to us, the march of ideas is explained by the march of things, the march of thought by the march of life.

Materialism sets dialectic on its feet and thus strips from it the veil of mystification in which it was wrapped by Hegel. Furthermore, in doing so, it -displays the revolutionary character of dialectic.

“In its mystified form, dialectic became the fashion in Germany because it seemed to elucidate the existing state of affairs. In its rational form, it is a scandal and an abomination to the bourgeoisie and its doctrinaire spokesmen because, while supplying a positive understanding of the existing state of things, it at the same time furnishes an understanding of the negation of that state of things and enables us to recognise that that state of things will inevitably break up; it is an abomination to them because it regards every historically developed social form as in fluid movement, as transient, because it lets nothing overawe it but is in its very nature critical and revolutionary."(From the preface to the second German edition to the first volume of Capital, 1873, new translation, 1928).

It is quite in order that the bourgeoisie, essentially reactionary, should regard materialist dialectic with horror. But that persons who sincerely sympathise with the revolutionary movement should disapprove of materialist doctrine is both ridiculous and sad – it is the climax of absurdity.

One more point has to be considered. We know already that Ueberweg was right, and we know how right he was, in demanding that those who think should think logically, and in demanding definite answers to definite questions as to whether this or that characteristic attaches to this or that object. Now, however, let us suppose that we have to do with an object which is not simple but complex and has diametrically conflicting properties. Can the judgment demanded by Ueberweg be applied to such an object? No, Ueberweg himself. just as strenuously opposed as Trendelenburg to the Hegelian dialectic, considers that in this case we must judge in accordance with another rule, known in logic under the name of “principium coincidentia oppositorum” (the principle of the coincidence of opposites). Well now, the immense majority of the phenomena with which natural science and sociological science have to do come within the category of such objects. The simplest globule of protoplasm, the life of a society in the very earliest phase of evolution – one and the other exhibit diametrically conflicting properties. Manifestly, then, we must reserve for the dialectical method a very large place in natural science and in sociology. Since investigators have begun to do this, these sciences have advanced with rapid strides.

Would the reader like to know how dialectic has secured a recognised position in biology? Let him recall the discussions regarding the nature of species that were aroused by the promulgation of the theory of evolution. Darwin and his adherents declared that the various species of one and the same family of animals or plants are only the differentiated descendants of a single primitive form. Furthermore, according to the theory of evolution, all the genera of one order are likewise derived from a single primordial form; and the same must be said of all the orders belonging to a single class. On the other hand, according to Darwin’s adversaries, all the species of animals and plants are completely independent one of another and only the individuals belonging to a single species can be said to derive from a common form. This latter conception of species had already been formulated by Linnaeus, who said: “There are as many species as the Supreme Being created in the beginning of things.” That is a purely metaphysical conception, for the metaphysician regards things and concepts as “distinct, unchangeable, rigid objects, given once for all, to be examined one after another, each independently of the others.” (Engels) The dialectician, on the contrary, Engels tells us, regards things and concepts “in their connection, their interlacement, their movement, their appearance and disappearance.” This conception has made its way into biology with the spread of the Darwinian theory, and has come to stay, whatever rectifications may be made in the theory of evolution as science advances.

To underline the importance of dialectic for sociology, it will suffice to recall how socialism has developed from utopism to science.

The utopian socialists regarded “human nature” from an abstract point of view and appraised social phenomena in accordance with the formula “Yes is yes, and no is no.” Property either was or was not conformable to human nature; the monogamic family was or was not conformable to human nature; and so on. Regarding human nature as unchangeable, utopian socialists were justified in hoping that, among all possible systems of social organisation, there must be one which was more conformable than any other to that nature. Hence their wish to discover this best of all possible systems, the one most conformable to human nature. Every founder of a school believed that he had discovered it, and that is why he advocated the adoption of his particular utopia. Mars introduced the dialectical method into socialism, thus making of socialism a science and giving the death-blow to utopism. Marx does not appeal to human nature; he does not know of any social institutions which either do or do not conform to human nature. Already in his Misère de la Phi1osophie, we find this significant and characteristic criticism of Proudhon; “Monsieur Proudhon is unaware that history in its entirety is nothing other than a continuous modification of human nature.” (Misère de la Phi1osophie, Paris, 1896, p. 204)

In Capital, Man says that man, by acting on nature outside himself and changing it, changes his own nature. This is a dialectical standpoint from which a new outlook on the problems of social life can be secured. Take, for instance, the question of private property. The utopists had written at great length” arguing with one another and with the economists, as to whether private property ought to exist, that is to say, as to whether private property was conformable to human nature. Marx put the question upon a concrete platform. According to his doctrine, the forms and relations of property are determined by the evolution of the forces of production. To one phase of evolution there corresponds a specific form of property; to another phase, another form; but there is no absolute solution, and cannot be one, for everything is in a flux, everything changes. “Wisdom becomes folly; pleasure, pain.”

Hegel says: “Contradiction leads forward.” In the class struggle, science finds a striking confirmation of this dialectical conception. Unless we take the class struggle into account, it is impossible to understand the evolution of social and mental life in a society divided into classes.

But this “logic of contradiction,” which, as we have seen, is the reflection in the human brain of the eternal process of movement – why should it be called dialectic:? I will not undertake a lengthy consideration of the question, and for answer I shall be content to quote Kuno Fischer:

Human life resembles a dialogue in this sense that, with age and experience, our views concerning persons and things undergo a gradual change, like the opinions of the interlocutors in the course of a lively and fruitful conversation. This involuntary and necessary change in our outlooks on life and the world is the very tissue of experience...That is why Hegel, when comparing the evolution of consciousness with that of a philosophical conversation. has given it the name of dialectic, or the dialectic movement. Plato, Aristotle, Kant, each of them employed this term in an important sense peculiar to himself; but in no philosophical’ system has it been given so comprehensive a meaning as in that of Hegel.”