Landmarks of Scientific Socialism: "Anti-Duehring"

by Friedrich Engels

In other words, the sovereignty of thought is realised in a number of highly unsovereign men capable of thinking, the knowledge which has unlimited pretensions to truth is realised in a number of relative blunders; neither the one nor the other can be fully realised except through an endless eternity of human existence.

We have here again the same contradiction as above between the necessary, as an absolute conceived characteristic of human thought, and its reality in the very limited thinking single individual, a contradiction which can only be solved in the endless progression of the human race, that is endless as far as we are concerned. In this sense human thought is just as sovereign as not—sovereign, and its possibility of knowledge just as unlimited as limited. It is sovereign and unlimited as regards its nature, its significance, its possibilities, its historical end, it is not sovereign and limited with respect to individual expression and its actuality at any particular time.

It is just the same with eternal truths. If mankind only operated with eternal truths and with thought which possessed a sovereign significance and unlimited claims to truth, mankind would have arrived at a point where the eternity of thought becomes realised in actuality and possibility. Thus the famous miracle of the enumerated innumerable would be realised.

But what about those truths which are so well established that to doubt them is to be, as it were, crazy? That twice two is four, that the three angles of a triangle are equal to two right angles, that Paris is in France, that a man will die of hunger if he does not receive food, etc.? Do we not perceive then that there are eternal truths, final truths of last instance? Quite so. We can divide the entire field of knowledge in the old-fashioned way into three great divisions. The first includes all the sciences which are concerned with inanimate nature and which can be treated mathematically, more or less—mathematics, astronomy, mechanics, physics and chemistry. If one like to use big words to express simple things, it may be said that certain results of these sciences are eternal truths, final truths of last instance, whence they are called the exact sciences. But all the results are by no means of this character. With the introduction of variable quantities and the extension of the variability to the infinitely small and the infinitely large, mathematics, otherwise erect, meets with its fall, it has eaten of the apple of knowledge and there has been opened up to it the path of limitless progress as well as that of error. The virgin condition of absolute purity, the undisturbable certainty of all mathematics has vanished forever, a period of controversy has intervened, and we have now arrived at the state of affairs in which most people carry on the operations of multiplication and division not because they really understand what they are engaged in, but from mere belief because the operation has so far always given correct results. Astronomy and mechanics, physics and chemistry are in a still more confused state, and hypotheses crowd one another thick as a swarm of bees. It cannot be otherwise. In physics we investigate the movements of molecules, in chemistry the development of molecules from atoms, and if the theory of light waves should not be correct we have no absolute knowledge that we even see these interesting things. The lapse of time produces a very thin crop of final truths of last instance. In geology we are in a still more embarrassing situation for we are here involved in the study of preceding epochs in which, as a matter of fact, neither we ourselves nor any other human being ever existed. Here there is much labor spent in the harvesting of truths of last instance, and they are a scanty crop withal.

The second division of knowledge is occupied in the investigation of living organisms. In this field the changes and causalities are so complex that not only does the solution of each question bring about the rise of an unlimited number of new questions, but the solution of each of these separate new questions depends upon years, frequently centuries, of investigation, and can then be only partially completed. So that the need of systematic arrangement of the various interrelations continually surrounds the final truths of the last instance with a prolific and spreading growth of hypotheses. Look at the long succession of progressive steps from Galen to Malpighi necessary to establish correctly so simple a thing as the circulation of the blood of mammals, yet how little we know of the origin of blood corpuscles and how many mistakes we make in, for example, rationally connecting the symptoms and cause of a disease. Besides there are frequently discoveries like those of the cell which compel us to entirely revise all hitherto firmly established truth of the last instance in biology, and to lay numbers of such truths aside for good and all. He who would therefore in this science undertake the proclamation of absolute and immutable truths must be content with such platitudes as the following: "All men must die; all female mammals have mammary glands, etc." He will not even be able to say that the greater animals digest their food by means of the stomach and bowels and not with the head because the centralised system of nerves in the head is not adapted to digestion.

But things are worse with regard to final truths of last instance in the third group of sciences—the historical. These are concerned with the conditions of human life, social conditions, forms of law and the state with their idealistic superstructure of philosophy, religion, art, etc., in their historic succession and in their present day manifestations. In organic nature we have at least to do with a succession of regular phenomena which regularly repeat themselves as far as our immediate observation goes, within very wide limits. Organic species have remained on the whole unaltered since the time of Aristotle. In social history, on the other hand, repetitions of conditions are the exception, not the rule, directly we leave behind the prehistoric conditions of humanity, the stone-age, so-called. Where such repetitions do occur, moreover, they never recur under precisely similar conditions, as for example the occurrence of early tribal communism among all peoples anterior to civilisation and the form of its break up. As regards human history, then, as far as science is concerned, we are at a greater disadvantage than in biology. Furthermore, when the intimate relations existing between a social and political phenomenon come to be recognised it is not, as a rule, perceived until the conditions are actually on the way to decay. Knowledge is therefore entirely relative, since it is limited to a given people and a given epoch, and their nature under transitory social and political forms, when it examines relations and forms conclusions. He who therefore is after final truths of last instance, pure and immutable, will only manage to catch flat phrases and the most arrant commonplaces, like these—man cannot, generally speaking, live without working; up to the present men have for the most part been divided into masters and servants; Napoleon died on May 5th, 1821, and things of that sort.

It is worth noting that in this department of knowledge pretended final truths of last instance are met with most frequently. Only the person who wishes to show that there are eternal truth, eternal morality, and eternal justice in human history, and that these are similar in scope and application to those of mathematics, will proclaim that twice two is four and that birds have beaks and the like to be eternal truths. We can also certainly rely upon the same friend of humanity taking the opportunity to explain that all former inventors of eternal truths have been more or less asses or charlatans, that they have been circumscribed by error and have made mistakes. The fact of their error, however, is natural and proves the existence of the truth, and that it can be reached, and the newly arisen prophet has a ready-to-hand stock of final truths of last instance, eternal law and eternal justice. This has happened hundreds, nay, thousands of times, so that it is a wonder that men are still sufficiently credulous to believe it not only of others, but even of themselves. Here we find a prophet clad in the armour of righteousness who proclaims in the old-fashioned way that whoever else may deny there is still one left to declare final truths of last instance. Denial, nay, doubt even, is a weakness, barren confusion, mole-like scepticism, worse than blank nihilism, confusion worse confounded and other little amiabilities of this sort. As with all prophets, there is no scientific investigation, but merely off-hand condemnation.

We might have made mention of the sciences which investigate the laws of human thought, logic and dialectics. Here we are, however, no better off as regards eternal truths. Herr Duehring explains that the dialectic proper is pure nonsense, and the many books which have been and are still being written on logic prove clearly that final truths of last instance are more sparsely distributed than many believe.

Moreover, we are not at all alarmed because the step of science upon which we to-day stand is not a bit more final than any of the preceding steps. Already it includes an immense amount of material for investigation and offers a great chance for specialisation and study to anyone who desires to become expert in any particular branch. Whoever expects to find final and immutable truths in observations which in the very nature of things must remain relative for successive generations, and can only be completed piecemeal, as in cosmogony, geology and human history, which must always be incomplete owing to the complexity of the historical material, shows perverse ignorance even where he does not, as in the present case, set up claims of personal infallibility.

Truth and error, like all such mutually antagonistic concepts, have only an absolute reality under very limited conditions, as we have seen, and as even Herr Duehring should know by a slight acquaintance with the first elements of dialectics, which show the insufficiency of all polar antagonisms. As soon as we bring the antagonism of truth and error out of this limited field it becomes relative and is not serviceable for new scientific statements. If we should seek to establish its reality beyond those limits we are at once confronted by a dilemma, both poles of the antagonism come into conflict with their opposite; truth becomes error and error becomes truth. Let us take, for example, the well-known Boyle's law, according to which, the temperature remaining the same, the volume of the gas varies as the pressure to which it is subjected. Regnault discovered that this law does not apply in certain cases. If he had been a realist-philosopher he would have been obliged to say, "Boyle's law is mutable, therefore it does not possess absolute truth, therefore it is untrue, therefore it is false." He would thus have made a greater error than that which was latent in Boyle's law, his little particle of truth would have been drowned in a flood of error; he would in this way have elaborated his correct result into an error compared with which Boyle's law with its particle of error fastened to it would have appeared as the truth. Regnault, scientist as he was, did not trouble himself with such childish performances. He investigated further and found that Boyle's law is only approximately correct, having no validity in the case of gases which can be made liquid by pressure when the pressure approaches the point where liquefaction sets in. Boyle's law therefore is shown only to be true within specific bounds. But is it absolute, a final truth of last instance within specific bounds? No physicist would say so. He would say that it is correct for certain gases and within certain limits of pressure and temperature, and even then within these somewhat narrow limits he would not exclude the possibility of a still narrower limitation or change in application as the result of further investigation. This is how final truths of last instance stand in physics, for example. Really scientific works as a rule avoid such dogmatic expressions as truth and error, but they are constantly cropping up in works like the Philosophy of Reality, where mere loose talking vaunts itself the supreme result of sovereign thought.