From International Socialism 2:65, Winter 1994.
Copyright © International Socialism.
Copied with thanks from the International Socialism Archive.
Marked up by Einde O’Callaghan for ETOL.
Engels and Marx had a lifelong interest in natural science. Both saw their politics growing from a materialist world view of which science was an integral part. Science, argued Marx, ‘underlies all knowledge’. 
Of the two founders of the Marxist tradition, Engels followed science more closely. He planned a major work setting out his approach to science, its history, place in society and the philosophical arguments surrounding it – but never completed it. Notes survive – some complete chapters, others in very rough form – which have been collected together and published as The Dialectics of Nature.  Engels never managed to fully develop his ideas. He was forced to break off work on The Dialectics of Nature to deal with arguments inside the then growing socialist movement. In Germany a now long forgotten professor, Dühring, had become fashionable among sections of the German workers’ movement. Engels was pressed by Marx, who was working on Capital, to write a polemic against Dühring.
This division of labour between the two men was typical, with Engels usually taking on the job of defending their joint views in public debate. Engels did not approach his task with enthusiasm. He wrote to Marx,
It is all very well for you to talk. You can lie warm in bed and study Russian agrarian conditions in particular and rent in general with nothing to disturb you. But I am to sit on the hard bench, swill the cold wine, suddenly interrupt everything again and tackle the boring Dühring. 
Dühring’s arguments are of little substance and Engels was scornful of what he called Dühring’s ‘bumptious pseudo-science’ in which he ‘speaks of all possible things and some others as well’.  Nevertheless, Engels took the opportunity in his polemic, known as Anti-Dühring, to lay out the basic world view that he shared with Marx. As Dühring had drawn on science to justify some of his arguments, Engels replied by spelling out some of his own ideas on science. Engels intended to resume work on The Dialectics of Nature, but was prevented from doing so by Marx’s death. Engels found most of his energies then tied up in preparing Marx’s unfinished Capital for publication, and also in meeting the growing demands placed on him to defend Marxism within the socialist movement.
Nevertheless, despite the unfinished nature of Engels’ project, it is possible to gather a fairly clear idea of his arguments about science. Ever since, those views have been the subject of fierce controversy, both among Marxists and between Marxists and those hostile to socialism. In the process Engels’ views have been distorted by both enemies and many would be friends.
The usual charges against Engels are twofold. On the one hand, he is accused of a crude and mechanistic form of materialism. On the other hand, he is charged with using notions drawn from the idealist philosopher Hegel which have no place in a materialist world view. Engels’ critics often manage to attack him for both these faults in the same breath, not noticing the contradiction. In fact the whole thrust of Engels’ writings on science is a polemic against both the views with which his critics tax him.  John Rees deals in detail elsewhere in this book with many of these attacks on Engels.  The aim of this chapter is to lay out what Engels said in his writings on natural science. In doing so I quote Engels’ words extensively and occasionally at length since they have too often been attacked on the basis of crude distortions. Engels’ arguments are then examined to see how they stand up against the enormous developments in natural science in the century since his death.
Engels enthusiastically welcomed every advance in a scientific understanding of the world. He located this attitude in the context of the battle between the two basic ways of understanding the world which have run through human history – materialism and idealism. The basic premise of materialism is that there is an objective world which exists independently of and predates human beings, human ideas and consciousness – or those of any supposed god. Most materialists would also hold that the world has definite ways of behaving, laws, which can be discovered and understood. Materialism, in its various forms, has long been opposed by another approach, idealism. This is the notion that the world is dependent on, has no existence apart from, some idea or consciousness. Most often this has meant some form of religion in which a god or non-physical being was a necessary precondition of all existence.
For most of human history idealism, usually in the form of religion, was the dominant approach in seeking to understand and explain the world. The balance, however, was decisively shifted in favour of materialism by the scientific revolution of the 16th and 17th centuries, associated with figures like Copernicus, Galileo, Kepler and Newton. Engels saw this revolution as intimately connected with the development of modern bourgeois society and the defeat of the old feudal society. It was a turning point in human history, a time when ‘the dictatorship of the Church over men’s minds was shattered’, the ‘greatest progressive revolution that mankind had so far experienced’. 
’Natural science’, Engels wrote, ‘developed in the midst of the general revolution and was itself thoroughly revolutionary’.  The first step in the scientific revolution was the theory put forward in 1543 by Copernicus that the Earth went round the sun and not the other way round. In throwing the Earth and man out of their place at the centre of the universe this marked a fundamental challenge to the old religion dominated view. Kepler went further and showed that the planets all moved not on perfect circular orbits, as established authority decreed, but rather on ellipses. Moreover, Kepler put forward the then revolutionary notion that the motions of the planets and motions of bodies on Earth could both be explained on the basis of the same physical principles. 
Galileo, using the telescope, recently developed for military purposes, shattered many other old established notions by showing that the Earth was not unique in having a moon. Jupiter had several. He found that the sun, in the established view a perfect, unblemished body, had dark spots. He also conducted systematic experiments and was the first to formulate an understanding of acceleration – change of velocity – which was a crucial step in explaining the dynamics of moving bodies. Newton went further still. He showed how all motion, from apples falling from trees to the trajectory of cannonballs and tides on Earth, to the motion of the Moon and all the planets, could be explained on the basis of his famous three laws of motion and the law of gravity. He also invented, along with the philosopher Leibniz, the mathematical calculus. This for the first time enabled processes involving continuous change to be precisely handled by scientists – for example velocity and acceleration.
Galileo and Newton were ‘giants’, but they were also products of the society they lived in. The problems they thought about and worked on were those thrown up by a society in which the bourgeoisie was expanding its wealth and power, and so transforming the way human beings interacted with nature.
The bourgeoisie’s drive to expand trade and production meant it had a vital interest in understanding and exploiting the natural world. It was this that lay behind the great scientific breakthroughs. Engels, in several of the sections of The Dialectics of Nature which remain as rough notes and sketches, links the development of science to the development of production. ‘From the very beginning the origin and development of the sciences has been determined by production’.  Engels never had time to spell out his argument, but a flavour of his approach can be gleaned from a few paragraphs:
If, after the dark night of the Middle Ages was over, the sciences suddenly arose anew with undreamt-of force, developing at a miraculous rate, once again we owe this miracle to production. In the first place, following the crusades, industry developed enormously and brought to light a quantity of new mechanical (weaving, clockmaking, milling), chemical (dyeing, metallurgy, alcohol) and physical (spectacles) facts.
This ‘not only gave enormous material for observation, but also itself provided quite other means for experimenting than previously existed, and allowed the construction of new instruments.’ In addition, ‘geographical discoveries – made purely for the sake of gain and, therefore in the last resort, of production – opened up an infinite and hitherto inaccessible amount of material of a meteorological, zoological, botanical and physiological (human) bearing’. 
Engels saw that scientific developments themselves changed society and production. Equally he understood that science also developed through its own internal dynamic – through attempts to make theories internally and mutually consistent. His point was to emphasise what was often forgotten: ‘hitherto, what has been boasted of is what production owes to science, but science owes infinitely more to production’.  As so often in his notes on science, Engels is forced to end with a hope he was never able to fulfil, ‘this to be studied further and in detail and to be developed’. 
Though the scientific revolution was a huge leap forward, it had a peculiar and one sided nature. ‘What especially characterises this period is the elaboration of a peculiar general outlook, the central point of which is the view of the absolute immutability of nature.’  At the core of this ‘Newtonian’ world view was the notion that ‘in whatever way nature itself might have come into being, once present it remained as it was as long as it continued to exist.’
The planets and their satellites, once set in motion by the mysterious first impulse, circled on and on in their predestined ellipses for all eternity. [The Earth] has remained the same without alteration from all eternity, or, alternatively, from the first day of creation. The ‘five continents’ of the present day had always existed, and they had always had the same mountains, valleys and rivers, the same climate, and the same flora and fauna, except in so far as change or transplantation had taken place at the hand of man. The species of plants or animals had been established once and for all when they came into existence. 
In contrast to the history of mankind, ‘which develops in time, there was ascribed to the history of nature only an unfolding in space’.  All change, all development in nature, was denied. And as a result ‘natural science, so revolutionary at the outset, suddenly found itself confronted by an out and out conservative nature, in which even today everything was as it had been from the beginning and in which – to the end of the world or for all eternity – everything would remain as it had been since the beginning’. 
Though science had challenged religion it was ‘still deeply enmeshed in theology’.  This static world view meant it often could give no answer to important questions. ‘How did the innumerable species of plants and animals arise? And how, above all, did man arise, since after all it was certain that he was not present from all eternity?’ To such questions ‘natural science only too frequently answered by making the creator of all things responsible. Copernicus, at the beginning of the period shows theology the door; Newton closes the period with the postulate of a divine first impulse’. 
Scientific developments in the 19th century challenged this static view of nature. These developments were spectacular, almost on a par with those of the years of Galileo and Newton. Too often the impression is given that the basic picture established by Newton underwent little change until the scientific revolution of the early 20th century associated with people like Albert Einstein. Nothing could be further from the truth. Nineteenth century science, growing in the midst of the industrial revolution, transformed our understanding of nature. Above all these developments proved that ‘nature also has its history in time’ , that everything in nature ‘does not just exist, but comes into being and passes away’.  This insight is the cornerstone of the whole of Engels’ approach to natural science.
The first breach in the static view of nature ‘was made not by a natural scientist but by a philosopher’.  The great 18th century German philosopher Immanuel Kant put forward the hypothesis that the Earth and solar system had evolved from a spinning gaseous cloud. Later the French scientist Pierre Laplace developed the scientific details of Kant’s notion. The details of the theory are thought not to be correct today, but it is right in many essential points. What mattered at the time was that, ‘if the Earth was something that had come into being, then its present geological, geographical and climatic state, and its plants and animals likewise, must be something that had come into being; it must have had a history’. 
This argument soon derived support from another quarter. ‘Geology arose and pointed out that not only the terrestrial strata formed one after another and deposited one upon another, but also the shells and skeletons of extinct animals and the trunks, leaves and fruits of no longer existing plants contained in these strata’.  The new geology, developed first by Charles Lyell, indicated that ‘not only the Earth as a whole but also its present surface and the plants and animals living on it possessed a history in time’. 
There remained, however, a contradiction between the new geology, with its view of the changing Earth, and the then assumed constant nature of plants and animals on the Earth. In this context Engels makes the perceptive comment:
Tradition is a power not only in the Catholic Church but also in natural science. For years Lyell himself did not see the contradiction, and his pupils still less. This can only be explained by the division of labour that had meanwhile become dominant in natural science, which more or less restricted each person to his special sphere, there being only a few whom it did not rob of a comprehensive view. 
Meanwhile physics too had undergone enormous developments in the 19th century. New sciences, of heat, electricity and magnetism had grown up alongside the already established understanding of the mechanics and dynamics of material bodies. These advances were intimately connected with the industrial revolution then transforming capitalist society. For instance, thermodynamics, the science of processes involving heat, was developed directly out of attempts to understand the principles behind, and improve the efficiency of, steam engines. 
At first these advances gave rise to a whole series of separate theories with each phenomenon being explained on the basis of a distinct physical, natural force. But in the mid-19th century a series of scientists forged a revolutionary breakthrough. Meyer in Germany and Joule in England first showed that mechanical motion could be transformed into heat and vice versa. Others then showed that both could be transformed into electricity, magnetism and chemical forces. They ‘proved that all so-called physical forces, mechanical forces, heat, light, electricity, magnetism, indeed even so called chemical force, become transformed into one another under definite conditions without any loss of force occurring’. 
The point was not just that science had demonstrated the transformations, but also that these transformations were law governed. Underlying them all was the principle dubbed the ‘conservation of energy’, which remains among the most fundamental principles of science. The total amount of energy remained the same but it could be transferred from one form to another. It was another mighty blow against the static world view. ‘With that,’ Engels wrote, ‘the special physical forces, the as it were immutable “species” of physics, were resolved into variously differentiated forms of the motions of matter, passing into one another according to definite laws.’  Later in the 19th century things were taken further when scientists showed that not only could heat and mechanical motion be transformed into one another, but that heat was in fact nothing more than the greater or lesser mechanical motion of the atoms or molecules of which a body was composed.
Chemistry too had undergone ‘wonderfully rapid development’ and ‘attacked the old ideas about nature’. Until the 19th century there seemed to be an unbridgeable gulf between ‘organic’ chemistry, that of living organisms, and ‘inorganic’. Now ‘the preparation by inorganic means of compounds that hitherto had been produced only in the living organism proved that the laws of chemistry have the same validity for organic as for inorganic bodies, and to a large extent bridged the gulf between inorganic and organic nature’. 
The old world view had come under attack ‘in the sphere of biological research also’. Biology had undergone a revolutionary transformation which had shattered for ever many of the old notions. ‘The more deeply and exactly this research was carried on, the more did the rigid system of an immutably fixed organic nature crumble away at its touch’.  These developments culminated in Darwin’s Origin of Species in 1859, and its theory of evolution by natural selection which put an end to the idea of fixed unchanging species. It showed that all species, including humans, had evolved from common ancestors. Engels enthusiastically wrote to Marx, ‘Darwin, whom I am just reading, is magnificent – there has never been until now so splendid an attempt to prove historical development in nature’. 
In every field Engels pointed out how the old ahistorical, unchanging view of nature had been challenged if not shattered by the results of science in the 19th century. In the new outlook ‘all rigidity was dissolved, all fixity dissipated, all particularity that had been regarded as eternal became transient’.  At the social level Marx and Engels had argued, in The Communist Manifesto, that in capitalist society ‘all fixed fast-frozen relations… are swept away, all new-formed ones become antiquated before they can ossify. All that is solid melts into air’.  In society this was based on capitalism’s ‘constant revolutionising of production, uninterrupted disturbance of all social conditions’.  Now the same process had pushed science to the point where it had undermined the old static view of nature and shown that change, constant transformation, was built into nature.
This view was not entirely new. In fact many of the great philosophers of classical Greece had such a view. After the one sided static world view born of the scientific revolution, modern science had ‘once again returned to the mode of outlook of the great founders of Greek philosophy, the view that the whole of nature, from the smallest element to the greatest, from grains of sand to suns, from Protista [very simple organisms] to man, has its existence in eternal coming into being and passing away, in ceaseless flux, in unresting motion and change’.  But there was an essential difference. ‘What in the case of the Greeks was a brilliant intuition, is in our case the result of strictly scientific research’. 
The recognition that nature has a history, that everything in nature is subject to change, comes into being and passes out of existence, is the starting point of Engels’ approach. But then it is necessary to understand how such change unfolds.
The first step in all real science is to examine separate phenomena, the ‘details’ of which ‘the picture of appearances’ is made up. ‘So long as we do not understand these [details], we have not a clear idea of the whole picture’. 
A necessary starting point was that ‘in order to understand these details we must detach them from their natural or historical connection and examine each one separately, its nature, special causes, effects etc.  Engels emphasises over and again the importance of this breaking up of nature – gathering, examining and seeking to understand facts about separate aspects of nature – as the first step in building up a real understanding:
The analysis of nature into its individual parts, the grouping of the different natural processes and objects in definite classes… these were the fundamental conditions of the gigantic strides in our knowledge of nature that have been made during the last four hundred years. 
The same approach remains the basic method by which most science proceeds, and must proceed, today. Both in Engels’ day and today many scientists would argue that this approach is what science is about, and that they have no need of ‘philosophy’ beyond this. But such an approach, often called empiricism, is not enough to understand the whole picture. It has severe inbuilt limitations.
Engels points to how many scientific ‘empiricists’ of his day had fallen prey to all sorts of claims by mystics, spiritualists and mediums. ‘The shallowest empiricism that spurns all theory and distrusts all thought’, Engels insists, ‘is the most certain path from natural science to mysticism’. 
Natural scientists believe that they free themselves from philosophy by ignoring it or abusing it … [but] they cannot make any headway without thought … [and] hence they are no less in bondage to philosophy, but unfortunately in most cases to the worst philosophy. 
The great danger is of ‘observing natural objects and processes in isolation, apart from their connection with the vast whole; of observing them in repose not in motion; as constants, not as essentially variables; in their death, not in their life’. 
Things and their mental reflexes, ideas, are isolated, are to be considered one after the other and apart from each other, are objects of investigation fixed, rigid, given once and for all… a thing either exists or does not exist; a thing cannot at the same time be itself and something else. Positive and negative absolutely exclude one another; cause and effect stand in a rigid antithesis one to the other. 
’At first sight’, says Engels, ‘this mode of thinking seems to us very luminous because it is that of so called common sense. Only sound common sense, respectable fellow that he is in the homely realm of his own four walls, has very wonderful adventures directly he ventures out into the wide world.’  He warns that breaking apart, considering separately aspects of nature, ‘justifiable and necessary as it is in a number of domains whose extent varies according to the nature of the particular object of investigation, sooner or later reaches a limit, beyond which it becomes one-sided, restricted, abstract, lost in insoluble contradictions. 
Engels gives a series of examples to illustrate the point: ‘For everyday purposes we know and can say, eg whether an animal is alive or not. But upon closer inquiry, we find that this is in many cases, a very complex question… it is just as impossible to determine absolutely the moment of death, for physiology proves that death is not an instantaneous momentary phenomenon, but a very protracted process’. 
Again even the notion of identity – to talk of this plant, that animal or this person – is frequently misleading.
The plant, the animal, every cell is at every moment of its life identical with itself and yet becoming distinct front itself, by absorption and excretion of substances, by respiration, by cell formation and death of cells, by the process of circulation taking place, in short by a sum of incessant molecular changes which make up life and the sum total of whose results is evident to our eyes in the phases of life – embryonic life, youth, sexual maturity, process of reproduction, old age, death.
The young boy, the mature man and the aged man are the same person, yet they are continually changing and different. ‘Abstract identity’, Engels says, ‘suffices for everyday use where small dimensions or brief periods of time are in question; the limits within which it is usable differ in almost every case and are determined by the nature of the object’. 
The point is of more general validity. It is necessary in beginning to detach aspects of nature from the rest, to isolate them from their connections, to focus on their existence, not their coming into being, passing away or transformation. But this can only partially grasp the reality of nature. We construct an understanding based on abstracting from some facets of the totality of nature. This process of abstraction helps us to look beneath surface appearances and see the essence of what is happening. These insights are then reintegrated into the totality from which they have been extracted, the better to explain the original appearance.
One simple example is Newton’s law of gravity. The core notion of this is that all bodies fall at the same rate – they are all accelerated at the same rate by the force of gravity. A consequence of this law is that a feather and a cannonball dropped from a tower will hit the ground at the same time. But we know that in reality a cannonball will hit the ground before a feather. To begin to explain what is really going on is quite difficult. We, like Newton, must abstract from appearances. Put aside the size and shape of the various objects. Put aside the air through which they fall. Imagine – or try to approximately construct – a situation in which we can ignore these factors. Only then can we grasp and formulate the underlying reality of a uniform acceleration due to gravity. And only then can we use that understanding to move back towards and explain the appearances. We can explain the various times at which objects acutally hit the ground by showing how air resistance, the shape of an object and so on produce deviations from what would be expected simply on the basis of the underlying natural law.
Engels argues that a similar process underlies all science. The very notions of ‘matter’ and ‘motion’, for instance, are of precisely this character. He attacks those who fail to see these concepts are abstractions from real experience, and ask about what is ‘matter as such’ or ‘motion as such’. 
Matter as such and motion as such have not yet been seen or experienced by anyone, but only the various, actually existing material things and forms of motion. Matter is nothing but the totality of material things from which this concept is abstracted, and motion as such nothing but the totality of all sensuously perceptible forms of motion; words like matter and motion are nothing but abbreviations in which we comprehend many different sensuously perceptible things according to their common properties. Hence matter and motion can be known in no other way than by investigation of the separate material things and forms of motion.
Engels gives as an analogy, ‘We can eat cherries and plums, but not fruit, because no one has so far eaten fruit as such’. 
Abstraction from appearance to understand the underlying essence is always based on focusing on some facets of nature and ignoring others. As a result, any such understanding always breaks down, is shown to be only partially correct, beyond certain limits. It fails to fit reality where what has previously been ignored can no longer be left out of the picture. We will see later how, for example, the 250 year old Newtonian law of gravity broke down in exactly this fashion in the early 20th century. Again, the centuries old notion of matter as billiard-ball-like lumps or particles broke down at the same time and in a similar manner.
Engels insists therefore that a fully rounded understanding which seeks to overcome these problems must be based on seeing ‘things and their representations, ideas, in their essential connection, concatenation, motion, origin and ending’  He calls for a ‘comprehensive view of the interconnections in nature by means of the facts provided by empirical natural science itself’. 
Engels called the approach he was arguing for ‘dialectical’. (The word derives from the philosophers of ancient Greece and means seeking truth through critical inquiry, disputation and argument.) It is a critique of static, fixed categories usually used in science-categories valid within certain limits, which differ according to the case, but which prove to be inadequate to fully grasp the nature of reality. There was no question for Engels of fitting facts about nature into some preconceived schema. ‘In every field of science, in natural as in historical science, one must proceed from the given facts … the interconnections are not to be built into the facts but to be discovered in them, and when discovered to be verified as far as possible by experiment’. 
Engels goes on to argue that having understood the details of how particular processes develop in nature a number of key general features can often be seen. He calls these ‘laws of the dialectic’. They are not laws in the sense of, say, Newton’s law of gravity, but operate at a quite different level of abstraction. They are ways of seeing the underlying pattern of a process of change after having worked out and understood the concrete details of the process concerned.
The first and most important of these is ‘the transformation of quantity into quality’, which Engels says is ‘rather obvious’.  Indeed it is, but it is nonetheless important for that. Modern science has shown, Engels argued, ‘that in nature, in a manner exactly fixed for each individual case qualitative changes can only occur by the quantitative addition or quantitative subtraction of matter and motion (so called energy)’. 
He gives a series of examples to illustrate the point. For instance, he takes the example of water (which has often been derided, but is a precise and excellent example). On heating water quantitative change, more or less heat, produces no qualitative change between certain limits. However, at certain critical points – the boiling and freezing points – a similar quantitative change then produces a dramatic qualitative transformation. The water freezes and becomes ice, or boils into steam. This is not just a question of human thought. Water does freeze and boil, did so long before human beings existed and, no doubt, will continue to do so long after we cease to exist.
Engels argues that this pattern – of the transformation of quantitative change into qualitative change at critical points – is a fairly general phenomenon in nature. ‘Every metal has its temperature of incandescence and fusion, every liquid its definite freezing and boiling point… every gas has its critical point at which it can be liquefied by pressure and cooling’.  He gives a whole string of other examples from science – which demonstrate that he was remarkably well informed of many of the very latest advances in natural science. Chemistry, he argued, ‘can be termed the science of the qualitative changes of bodies as a result of changed quantitative composition’. 
For instance, ‘the case of oxygen. If three atoms unite into a molecule instead of the usual two we get ozone, a body which is very considerably different from ordinary oxygen in its odour and reactions’.  And Engels points to the discovery of the periodic table of elements by Mendeleyev, in which he showed that certain qualitative properties of elements are periodic functions of their atomic weights, as further demonstration of how in nature quantitative change is at certain points transformed into qualitative leaps.
Engels noted that ‘probably the same gentlemen who up to now have decried the transformation of quantity into quality as mysticism and incomprehensible transcendentalism will now declare that it is indeed something quite self-evident, trivial and commonplace, which they have long employed, and so they have been taught nothing new.’ Well, Engels replied, ‘if these gentlemen have for years caused quantity and quality to be transformed into each other, without knowing what they did, then they will have to console themselves with Molière’s Monsieur Jourdain who has spoken prose all his life without having the slightest inkling of it’. 
Engels goes on to argue that change in nature is also often characterised by ‘the interpenetration of opposites’  or the ‘motion through opposites which asserts itself everywhere in nature’  or development through ‘contradictions’. And he argues that a further characteristic typical of processes of change is ‘the negation of the negation’ – development through a new synthesis emerging which surpasses and transforms the elements of the ‘contradiction’. To see changes in the way Engels describes is for him not a substitute for understanding the ‘particular process’ itself. 
Engels gives a series of examples to illustrate the kind of processes he means. In Anti-Dühring, a polemical work, some of these examples are fairly trite and some are circular processes which do not really demonstrate the qualitative development that Engels claims to be illustrating. But scattered among the notes in The Dialectics of Nature a picture of what he is grappling with can be found. For instance, Engels discusses the question of living organisms, what following the best scientific understanding of his day he calls ‘albuminous bodies’ (today we would talk of bodies based on DNA, RNA and protein molecules). A condition of existence of any living organism is that it ‘absorbs other appropriate substances from its environment and assimilates them’:
Non-living bodies also change, disintegrate and enter into combinations in the natural course of events, but in doing this they cease to be what they were. A weather worn rock is no longer a rock, a metal which oxidises turns into rust. But what with non-living bodies is the cause of destruction, with albumen is the fundamental condition of existence… this uninterrupted metamorphosis [which] essentially consists in the constant self-renewal of the chemical constituents of these bodies.
Life therefore consists primarily in the fact that every moment it is itself and at the same time something else; and this does not take place as the result of a process to which it is subjected from without … on the contrary … [it] is a self-implementing process which is inherent in, native to, its bearer. 
The first point is about how things maintain their unity, their identity, in the face of external impulses, effects and pressures to change. These pressures ‘negate’ the object (quite literally in the example of rust Engels mentions). But some material objects have the capacity to react quite differently to such pressures – in so far as such an object absorbs these pressures, and in the process may change itself while preserving itself, it ‘negates the negation’. Indeed, in the second paragraph quoted above, Engels hints at the possibility of self, or internally generated, change – that is, a self contained totality which evolves under the impact of its own internal ‘contradictions’ (though the particular example he uses does not quite fit). Engels himself never fully developed these ideas, but he is trying to grasp the essence of a pattern, or possibility, of a process of change exhibited by some aspects of the natural world. It is not a formula nor is it a substitute for an investigation and explanation of ‘the particular nature of each individual case’. 
Engels has sometimes been attacked because some of the science he quotes has since been shown to be wrong. For instance, Engels did believe in the ether, a supposed medium filling all space through which light waves propagated. He was also inclined to accept, for example, the doctrine in evolution known as Lamarckism, the notion that, in addition to natural selection, evolution may also be based on the inheritance of acquired characteristics. We should remember, however, that in the first case all scientists of Engels’ day supported the notion of the ether, and in the second case most biologists of Engels’ day, including Darwin, agreed with him on the possible inheritance of acquired characteristics. Both these views have since been shown to be wrong. But it is unfair to attack Engels for sharing views supported by the best scientists of his day. We should also remember that Engels’ writings on science are preliminary thoughts, often rough notes, rather than a fully worked out view. He ends The Dialectics of Nature with, ‘All this has to be thoroughly revised’. 
Engels insisted, however, that his general approach was backed up by the findings of modern science. ‘Nature is the proof of dialectics, and it must be said for modern science that it has furnished the proof with very rich materials, increasing daily’.  How does this claim stand up against the developments in science in the 100 years since Engels’ death?
In the century since Engels’ death almost every area of science has been radically transformed by new breakthroughs in our understanding of nature.
Geology, for instance, has been revolutionised by the theory of plate tectonics, or ‘continental drift’. Instead of seeing the land masses on the Earth’s surface as permanent features we have a scientific understanding of the way they have developed, changed and moved during the Earth’s history. Nor is this a finished process: the continents continue to move today. New land is continually being created and existing continental material destroyed. The new understanding means we can begin to explain the development and change of natural phenomena from mountain ranges to oceans and earthquakes in a way that was impossible before. The understanding of plate tectonics also casts new light on biological evolution.
For a long time many geologists resisted the theory of plate tectonics, despite the growing evidence in its favour. It has only been fully accepted in the last 30 years or so. These scientists would perhaps have been less resistant to the new understanding if they had been accustomed to think in the spirit of Engels’ argument that all of nature changes, that what appears to be static and fixed usually turns out to be otherwise. Of course Engels knew nothing of plate tectonics, but his general attitude did lead him to warn against the idea that ‘the five continents of the present day had always existed’. 
Biology has undergone an even more revolutionary transformation since Engels’ death. First Mendelian genetics, then in more recent decades molecular biology – and a host of other advances – have transformed our understanding of living organisms. But, as so often with powerful new breakthroughs, the very success has bred a distorted one sided view among many biologists. In biology this is often linked to political and ideological questions – as arguments about human biology easily lead to arguments about human nature and society.
The fashionable approach, at least among molecular biologists, is best termed a ‘reductionist determinism’. In this view everything about, say, human biology and behaviour is a mechanically and directly determined consequence of our genes – strings of DNA molecules inside every cell in our bodies. At its most extreme this leads to claims that there are genes for aggression, homosexuality, criminality, homelessness and the like. It leads to sociobiology, in which human behaviour and social development are viewed as a direct consequence of our genes – so war, sexism, racism and so on are seen as a product of our biological evolution. And it leads to a view of human beings as robot like receptacles manipulated by ‘the selfish gene’. Without going this far many biologists argue as though genes are all that really matter, all we need to know to understand our biology and even our behaviour.
Most of this is a mixture of poor science, ideology, and fanciful ‘just so’ stories about evolution. Some of those pushing such arguments are motivated by reactionary politics. Others are influenced, often unconsciously, by the money available for research in these areas – molecular biology and genetics are big business today. Some are simply carried away with the real success of molecular biology and genetics in advancing our understanding into generalising from this to a mistaken overall view, in much the same way as Engels argued happened to many scientists after the 16th and 17th century scientific revolution.
Fortunately, there are a growing number of eminent biologists who forcefully challenge this approach. Two of the most well known who have written popular works expounding their view are Richard Lewontin in the US and Steven Rose in Britain. They argue that a proper understanding of biology, and of the huge advances of recent decades, demands a totally different approach, what they themselves call a ‘dialectical biology’. Moreover, these scientists frankly acknowledge that their general approach is inspired by Engels, as can be seen from the work contained in such books as Not in Our Genes, The Making of Memory, The Doctrine of DNA and The Dialectical Biologist  – none of which demand a formal or technical training in biology.
There are two reasons for dealing in greater detail with the advances in physics since Engels’ death. Firstly, the revolution in physics of the last 100 years has been the most spectacular in any science. It has radically transformed the most basic notions which underpinned all previous science. Secondly, while in biology there are at least some eminent working scientists, even if they are a minority, who argue for a dialectical approach, this is not the case in physics.
The difference can be illustrated from a glance at the 1993 shortlist for the prestigious annual Rhone-Poulenc science book prize. The eventual winner was The Making of Memory by Steven Rose. This is a beautifully written account of how science works by someone who has made major contributions to it. It is also a sharp critique of reductionist and determinist biology and an unashamed defence of what the author has called ‘a dialectical biology’.
Steven Rose’s book was in fact a surprise winner of the award. The pre-award favourite was instead The Mind of God, a book on modern physics by the eminent theoretical physicist Paul Davies. In it he claims the lesson of physics today is that, ‘We have to embrace a different concept of understanding from that of rational explanation. Possibly the mystical path is a way to such an understanding’. 
Davies’s previous work was also a popular best seller on modern physics written with John Gribbin, a respected scientist, an astrophysicist by training and physics consultant for the reputable New Scientist magazine. The title of their book indicates their key argument. It is called The Matter Myth. Their central thesis is that ‘materialism is dead… During this century physics has blown apart the central tenets of materialist doctrine in a sequence of stunning developments’.  They go on to indicate what these developments are: ‘first came the theory of relativity … then came the quantum theory … another development goes further, the theory of chaos’. 
If these authors, and they are fairly typical of much that passes for serious thinking about modern physics, are right it is a serious matter. It is therefore worth looking at the argument in some detail. In fact, far from undermining materialism the very advances cited by these and similar authors are in fact huge advances in a materialist understanding of nature. Moreover, they are also a marvellous confirmation of the general arguments put forward by Engels, weighty evidence for the necessity of a dialectical approach to understanding the natural world. The first two of the scientific advances cited, relativity and quantum theory, were part of the revolution which transformed science in the first few decades of this century, most famously associated with the work of Albert Einstein.
This revolution arose from a profound crisis in science. By the time of Engels’ death there were a series of glaring contradictions between different branches of physics. Theories which successfully explained different physical phenomena contradicted each other in fundamental ways. It was out of the attempt to resolve these contradictions that the new scientific revolution was born. A new, deeper understanding was built which went beyond the previous contradictory elements, and at the same time showed why these had worked within certain limits. This process is a fairly typical one in the history of science. In the historical development of scientific ideas Engels’ arguments about how change takes place are well grounded.
Relativity theory was developed by Einstein between 1905 and 1915. The first step, known as ‘special relativity’, was born of a contradiction between theories of motion, dynamics, on the one hand, and theories of electromagnetism – phenomena such as radio and light waves as well as electric and magnetic forces – on the other. In dynamics, Newton’s laws of motion had stood the test of over two centuries. Then in the 1860s James Clerk Maxwell had put the understanding of electromagnetism on a similar footing by describing all electromagnetic phenomena in terms of a series of simple and beautiful laws. Maxwell’s equations were a huge breakthrough, they enabled the prediction of radio waves and led to a host of other developments, and they remain today a key element of modern science.
The problem, though, was that there was a contradiction between Newton’s laws and Maxwell’s. The crux of the matter is that Newton’s laws appeared to remain the same for any two observers moving at constant velocity relative to each other while Maxwell’s didn’t. This led to all sorts of contradictions. For example, it meant two different physical explanations of the electrical dynamo and motor – one converting electricity to motion, the other the reverse – processes which appeared in fact to be connected. Einstein solved the problems by going beyond both existing theories.
The cornerstones of relativity are two principles about nature first put forward by Einstein in 1905. The first – in view of the contradiction between Newton and Maxwell – was to insist that the laws of physics must be the same for any observer no matter what their velocity. The second principle is that the velocity of light is constant, the maximum velocity possible in nature, and that its velocity is independent of the motion of the source of that light.
It is the last part of this that seems outrageous. Imagine measuring the speed of a ball thrown to you and finding it to be the same whether the ball is thrown by a motionless friend standing nearby or from another friend speeding by in a supersonic aircraft. Since the speed of such balls would not be the same why should it be for light? But when looking at nature we should always bear in mind Engels’ warning about the dangers of ‘sound common sense’. For in fact it does turn out that if you measure the speed of light it is always the same, no matter how fast you yourself or the source of the light may be moving. This is now a well established fact of nature.
A series of consequences follow from Einstein’s arguments which seem to challenge commonsense notions of time and space. These new notions have since been tested and confirmed in countless experiments. The old notions are themselves abstractions, generalisations, from how the world behaves when things are moving at low speeds relative to ourselves. Einstein showed that those notions break down and do not fit the way real material objects behave at speeds which begin to approach the speed of light. This is why Maxwell’s electromagnetic theory, which deals with light waves, did not sit happily with Newton’s laws. A crucial element in the new understanding is that what appear to be simultaneous events to one observer may not appear to be so for another observer moving relative to the first. Another consequence is that moving clocks run slow. An accurate clock flown round the world on a jet will show a different time on return to an exactly similar clock left at home. For most phenomena we have direct experience of, the effect is tiny, but it becomes large and important as speeds approach that of light.
Einstein’s theory was a key step in the defeat of the notion implicit in Newtonian physics of an absolute space and time, and absolute motion. It was a vindication of the idea that all motion was relative. Also, until Einstein, physics had seen matter, mass, as something dead and inert which had to have energy imparted to it. To be sure, energy could be transformed from one form to another but mass itself was something quite distinct. Now Einstein’s relativity, with its famous equation E=mc², showed that mass could be transformed into energy and vice versa.
Einstein later extended his theory to provide a new explanation of gravity, which had not been incorporated into his earlier theory of ‘special relativity’. ‘General relativity’ starts from a simple fact. In Newton’s theory mass appears, but there are two different masses – what are known as the gravitational and inertial masses. One is the mass which is the source of the force of gravity, the other is the measure of a body’s resistance to change of motion. In fact the two, though in Newtonian physics quite distinct aspects of matter, are always found to be the same. Weightlessness in a falling lift is one example. Einstein’s theory is an attempt to explain facts like this. It attempts to incorporate gravity into the new relativistic dynamics.
General relativity is not, as often presented, simply an exotic tool for speculation about the universe – though it can help in that too. Something as straightforward as the orbit of the planet Mercury around the sun was never fully explained by Newton’s laws – despite the best efforts of generations of brilliant physicists, astronomers and mathematicians. General relativity now makes it possible to explain it. Again the theory was spectacularly confirmed in 1919 when its novel prediction that light from stars should bend when it passed close to the sun was shown to be correct.
There certainly are difficult mathematics in general relativity’s description of matter and space. For instance, it insists that the geometry of space containing matter is not Euclidean – the kind we are taught at school – but rather what is called ‘curved’. A way to try and picture the difference is to compare the kind of geometry possible on the surface of a balloon to that on a flat surface. On the flat surface the three angles of a triangle always add up to 180 degrees. On a balloon this is not true. On a flat surface a line never joins itself no matter how far extended, on a balloon this is again not true. In general relativity, however, the ‘curved’ geometry is in the three dimensions of space (or, strictly speaking, the four dimensions of space – time) not just on a two dimensional surface, whether flat or balloon like. Despite the difficulties however, the final form of the theory is the most beautiful and elegant in modern physics. And the key notion in the theory is not so difficult. It is simply that the old notion of matter which exists in a passive, unaffected background of space will not do. Rather matter and the space it exists in are connected and influence each other in fundamental ways. The geometry of space and the distribution of matter mutually determine each other.
Neither special nor general relativity are in any way a challenge to materialism. By the turn of the century existing scientific theories simply could not explain a growing number of observed facts of nature and, moreover, the theories that explained different facets of nature contradicted each other. The new theories resolved those contradictions, explained the unexplained, and showed both why the old theories had worked within limits and why they broke down beyond those limits.
Engels certainly had no inkling of relativity theory, or that the 200 year old Newtonian laws of motion and gravity were to be overturned within years of his death. But the development of relativity and its core notions illustrate many of Engels’ key arguments. He had insisted that all motion was relative. ‘Motion of a single body does not exist, it can be spoken of only in a relative sense’.  More importantly, the whole thrust of relativity theory is a precise illustration of Engels’ argument that abstractions which fit aspects of nature within certain limits then break down when pushed beyond those limits, and thus require a new understanding. Again the new understanding that matter was not something separate from motion and energy but that each was capable of being transformed into one another in a definite law governed manner is exactly the kind of process Engels pointed to as a unity of opposites, a characteristic revelation of a deeper understanding of nature. Someone who had argued that the science of his day pointed to the fact that motion and transformation were ‘the mode of existence, the inherent attribute, of matter’ would have been less surprised than many by relativity theory.
Finally, the key notion in general relativity, that space and matter were not mutually opposed aspects of nature, with matter existing against a passive backcloth of space, but that the two were intimately connected and mutually determining, is, again, about as sharp an example as you could find of the interpenetration of opposites, the kind of ‘dialectical’ understanding Engels argued for and which he insisted scientific advances increasingly demanded.
The second revolution in the early part of the century came with quantum theory. This too came out of glaring contradictions between existing theories and observed facts – especially in the behaviour of small objects like atoms.
Atoms, for instance, simply should not exist on the basis of the old understanding. If Newton and Maxwell were right – even when reconciled by relativity – then every atom should collapse in a burst of radiation in a very short time. This, fairly obviously, is not true. It was out of such problems – and a host of others ranging from the behaviour of metals when ultraviolet light was shone on them to how bodies absorbed and emitted radiation – that quantum mechanics developed.
At first this was done on a fairly ad hoc basis – simply adding in bits to old theories even if these bits flatly contradicted other parts of the theory. But in the 1920s and 1930s a radically new theory was developed. Three aspects of this ‘quantum mechanics’ are important. Firstly it argues all objects can behave as both waves, like radio waves, and bulletlike particles. So light, usually thought of as a radio-like wave, can behave as a particle, while an electron, a particle, can also behave like a wave. What had previously, and still now to common sense, seemed two mutually exclusive and opposed notions were revealed to be intimately connected, to be two sides of the same coin.
Secondly, quantum mechanics also says there is an intrinsic uncertainty in nature. For instance, an electron can have a well defined and precise position or velocity, but not both at the same time. Thirdly, the theory says some phenomena in nature are inherently probabilistic, governed by chance. So it is impossible to predict in advance, say, which of the various possible energies an electron around an atom will be in or exactly when a radioactive particle will emit radiation.
It suggests this randomness is not the same as that, for example, of rolling a die or tossing a coin, but fundamental. In coin tossing the randomness is a result of our ignorance. If we measured the initial motion of the coin as it left our hands then we could predict which way it would land. The randomness in quantum mechanics is not of this kind, not simply a result of our ignorance. Rather it suggests that, for example, it is not possible even in principle to predict exactly which energy is possessed by an electron around an atom. Instead it suggests that all we can do is predict the probability of it having each of the range of possible energies.
One point should be emphasised. Quantum theory does not throw determinism out of the window and leave us with a picture of a world completely governed by chance, random events. It is rather a picture of a world of subtle interplay between chance and necessity. Quantum theory deals with predicting the probability of events, such as an electron around an atom having a particular energy, and how those probabilities evolve in time in a strictly deterministic fashion. Quantum theory deals mostly with very small atomic scales and, as it has to, agrees with older theories on how large, macroscopic, objects behave. Moreover it seeks to explain how uncertainty at the small scale results in the quite predictable and deterministic behaviour characteristic of the larger, macroscopic, scale of which we have direct experience.
Many features of quantum theory seem bizarre and run counter to many common sense assumptions. Yet it makes sense of real facts about nature which on the old understanding could not be explained. It has been spectacularly confirmed in countless experiments. Your TV or pocket calculator wouldn’t work if its predictions weren’t accurate. It is a step forward in a materialist understanding of the world, not a retreat.
Nevertheless there are severe problems in interpreting quantum theory, despite its predictive success. Quantum theory describes matter in terms of something known as a ‘wave function’ – which sums up the fact that all matter has both wave-like and particle-like attributes. There is deep and unresolved controversy among scientists about what this ‘wave function’ means. Most scientists think of it as a kind of description of all the possible states open to the matter under consideration at any time and a measure of the relative probability of that matter, say an electron around an atom, being in any of those states. When the matter under consideration interacts with something else, most obviously when it is measured, it is found to be in one definite state. This is called the ‘collapse of the wave function’. There is again huge and unresolved controversy among scientists about this process. No one knows the answers.
Many physicists simply get on with using the theory, which has been among the most successful in the history of science. They push the problems to one side. The long time ‘orthodox’ interpretation of quantum mechanics, usually called the Copenhagen interpretation, is little more than a gentlemen’s agreement not to ask awkward questions.
A lot of good things have been written on the problems thrown up by both quantum mechanics and its relation to our understanding of other aspects of nature. As yet, though, they remain unresolved questions. Those who think science is a closed world free of contradiction and with definite answers to all questions are very mistaken. 
It is also true that quite a lot of nonsense has been written by quite reputable and otherwise quite sane scientists. Some, for instance, argue that a conscious observer is necessary for the collapse of the wave function. Seeing as the world – and the collapsing wave functions – certainly existed long before human beings, this is simply another way of describing god. Another notion that is quite fashionable is what is sometimes called the ‘many worlds’ interpretation of quantum mechanics. This argues that every ‘measurement’ results in the universe splitting into parallel worlds all of which really exist.  It avoids the real problems associated with the ‘collapse of a wave function’ by saying it doesn’t really happen, but instead all the possibilities summed up in the wave function really turn out to be true, each in one of a myriad of parallel universes. This may be the stuff of interesting science fiction, but as serious science it leaves a lot to be desired.
Amid all the unresolved problems we should remember that the contradictions and problems with the newer theories are not essentially worse than those with older theories – it is just that we are used to ignoring the earlier problems. For instance, in Newton’s theory of gravity, force is supposed to act instantaneously at any distance. A little thought will reveal that this really is a bizarre notion, which didn’t stop people using the theory for hundreds of years and continuing to use it within certain limits today. The great 19th century scientist Michael Faraday was one of the few who, long before Einstein, pointed out the difficulty of the ‘spooky action at a distance’ at the heart of Newton’s theory.
Whatever the correct interpretation of quantum mechanics turns out to be, there is no doubting that it is not a challenge to materialism, but a step forward in a materialist understanding. Once again the problems it gives rise to should be set against the fact that the old theories simply could not explain elementary facts about nature while quantum mechanics does, and in addition has led to enormous advances across a whole range of science and technology.
However, given the deep and unresolved problems within it, quantum theory is unlikely to be the last word on how matter behaves at a subatomic level. At some point a new understanding will be developed which will resolve some of the problems. No doubt, it will in turn throw up fresh contradictions and problems. John Bell, a leading figure in quantum theory, said:
The new way of seeing things will involve an imaginative leap that will astonish us. In any case, it seems that the quantum mechanical description will be superseded. In this it is like all theories.
And he concluded in a phrase that echoes Engels’ whole approach to science: ‘To an unusual extent its [quantum mechanics’] fate is apparent in its internal structure. It carries in itself the seeds of its own destruction’. 
Engels would have been as shocked and surprised as anyone at the picture of the subatomic world thrown up by the development of quantum mechanics. But many of quantum theory’s key notions illustrate Engels’ arguments about nature. It shows how chance and necessity are not mutually exclusive opposed notions, how in fact chance at one level of nature can give rise to deterministic behaviour at another level. It shows that old notions, of wave-like behaviour and particle-like behaviour, which fit most aspects of nature of which we have direct experience, break down when pushed past certain limits and instead require a new understanding to be developed.
The leading British scientist John Haldane (typically, though, a biologist!) writing in 1940, after discussing Engels and the various points on which he was wrong, commented, ‘When all such criticisms have been made, it is astonishing how Engels anticipated the progress of science in the 60 years which have elapsed since he wrote … Had Engels’ methods of thinking been more familiar, the transformation of our ideas on physics which have occurred during the last 30 years would have been smoother’.  Quantum theory and relativity, though now well established and accepted, were controversial for many years after they were born. Looking back at the controversy after reading Engels, Haldane concluded, ‘Had these books been known to my contemporaries, it was clear that we should have found it easier to accept relativity and quantum theory’. 
In the decades since the development of quantum theory our understanding of the basic structure of matter has been further revolutionised. Whereas 60 years ago it was thought all matter was made up of protons, neutrons and electrons which were acted upon by eletromagnetic and other forces, now a much richer picture has been uncovered. Protons and neutrons have been shown to be complex systems made up of more ‘elementary’ objects called quarks. New forces have been discovered and explained, such as the ‘colour’ force (which, in fact, has nothing do with colour) thought to be responsible for the interaction between quarks. Every few years some scientists think they have found the ‘ultimate building blocks’ of matter or a ‘theory of everything’. But it has always turned out that, once probed beyond certain limits, the ultimate turns out to nothing of the kind, and that matter and its behaviour are an inexhaustible fount of surprises.
Even the notion of the vacuum, empty space, has now been shown to be mistaken on closer investigation. Rather the vacuum seems to be a bubbling sea in which particles, packets of matter and energy, continually froth in and out of existence. This is not just speculation. This process plays a key role, for example, in the spontaneous emission of light by some atoms. The general picture emerging from modern physics is that change, continual process, interaction and transformation are a fundamental property of matter, and of the space which can no longer be seen as separate from it.
The most striking thing about the picture of matter in physics today is how well it sits with Engels’ arguments about all of nature having a history, how seemingly separate facets of nature are connected, and how the essence of matter is precisely its continual transformation and change.
For instance, it is now thought that all the known forces and particles of nature are connected (all forces are now thought to be carried by particles of matter, or energy – the two are equivalent). The emerging view is that all the fundamental forces of nature are in fact different aspects of a single unified force. Moreover, in this new understanding nature has a history in a sense far more fundamental than even Engels thought possible, though very much in the spirit of his arguments.
It seems that at the very high energies typical early in the history of the universe all the forces were unified. As the universe has expanded and cooled, and so the typical energies of processes have fallen, this symmetry, this unity, has repeatedly been broken until today, at the energies we can now usually have access to, the various forces and their associated particles appear as separate and distinct.
Moreover, all the known ‘particles’ and ‘forces’ of matter are simply different and transient manifestations of the same underlying essence (which most scientists would today call energy). They are all capable of being transformed into another. So, for instance, a proton and an anti-proton (two particles which are identical except the ‘anti’ particle has the opposite electrical charge) mutually annihilate each other if they meet. The released energy, or more accurately transformed matter, can then go through further transformations and so give rise to a host of other different ‘particles’ of matter.
Again the generally accepted explanation for the development of the universe – known as the ‘standard cosmological model’ or more popularly the ‘big bang’ – is one in which matter has undergone repeated qualitative transformations when quantitative change has reached critical points. That development has proceeded through a dynamic internal to matter. Differentiated facets of the totality of matter, which has an underlying unity, have been progressively transformed as they mutually interact. We have an evolution from quarks, to protons and neutrons, to neutral atoms, to gas clouds, stars and galaxies, the formation of heavier elements like carbon, the formation of planets and through a series of further transformations to the emergence of organic life and conscious human beings. 
At each stage qualitatively novel behaviour of matter emerges. So quarks having existed freely were, when the temperature of the universe fell below a critical point, permanently confined inside particles like protons and a qualitatively new kind of physics emerges (at the energies existing in the universe today free quarks cannot exist). Later, below another critical point, protons and neutrons could capture electrons and the whole possibility of the rich new arena of atomic and molecular processes emerges for the first time. It needed the first such molecules to be further transformed in the very special conditions of stellar interiors, and then those stars themselves to explode in cataclysmic events called supernovae, before the elements crucial to the formation of planets like Earth were even possible. And a further long series of transformations of matter have, billions of years later, resulted in the qualitatively new phenomena of human beings, consciousness and society.
Even a cursory acquaintance with what 20th century physics has uncovered about nature and its various aspects and historical development shows that Engels’ general approach is more relevant than ever.
The final development cited as challenging materialism is chaos theory. This has only fully developed in the last 30 years. Many of the problems and issues it deals with were raised by scientists long ago, above all Henri Poincaré at the turn of the century. But the investigation of the problems only became possible with the development of the modern fast computer.
Chaos theory basically says that some physical systems, though governed by laws which predict exactly what something will do, can nevertheless behave unpredictably. The weather is the example most often cited, usually in the picturesque example of the ‘butterfly effect’ – in which it is said the flapping of a butterfly’s wings on one side of the world can ultimately result in changes which accumulate in such a way as to lead to a hurricane on the opposite side of the globe.  In fact very simple physical systems also behave in this ‘chaotic’ way. Three bodies orbiting each other under the influence of gravity, or a simple pendulum swinging over a magnet are two examples. Such physical systems are unpredictable in that their evolution is so sensitive to tiny changes in the initial conditions from which that evolution starts that the only way to see what happens is to wait and see.
This theory has been seized on to argue that any attempt to explain the world, to consciously act to change it in a certain way, is doomed to failure. All we are left with is unpredictability and chaos. Attempts at social or economic planning won’t work, the chaos of the market is all that’s possible, runs the argument. This is to miss the whole point of the theory. It deals mainly with phenomena which previously were not understood at all. Now where ignorance reigned something can be explained, even if some old notions have to be rethought to do so. In fact chaos theory shows there is a pattern, a structure – albeit often a very complicated one – underlying many phenomena previously not understood at all. The dynamics of heart attacks, or fluid turbulence, to take just two examples, have never been really understood. Now chaos theory has provided the first steps of an explanation. 
Chaos is a property of what mathematicians call non-linear systems. Until the last few decades almost all physics for the last 300 years dealt with what mathematicians call linear systems. Linear systems are much easier to deal with mathematically. The basic difference is that in a linear system the whole is equal to the sum of the parts, while in a non-linear system the whole is not simply the sum of the parts – an idea that has been fundamental to a dialectical understanding at least since Hegel.
Great strides forward can be and have been made by studying those parts of nature which can be approximately taken as linear. But all real physical situations are non-linear. Sometimes the non-linear effects can be ignored, but very often they cannot. Because non-linear mathematics is far more difficult to deal with than linear, most science shied away from non-linear problems until the advent of fast computers and chaos theory.
Two key aspects of chaos theory are interesting. Firstly, it shows that at various points small quantitative changes produce large qualitative changes in behaviour. Chaos theory is saying, and explaining why, this – as Engels argued – is a fairly universal feature of the natural world.
Secondly chaos theory shows that in the natural world determinism and unpredictability, seemingly two opposed and mutually exclusive notions, are in fact intimately linked. A process can in a very real and important sense be both at the same time.  In quantum theory unpredictability at one level can give rise to deterministic behaviour at another level of nature. Chaos theory shows the opposite is also true. A system can be governed by strictly deterministic laws yet give rise to unpredictable behaviour.
Again this is not a result of ignorance. When specifying the initial conditions of any system there is always a margin of error, summed up in the notion of something being ‘correct to within one part in, say, 100 million’. In a ‘chaotic’ system, no matter how small this margin of error is, it can be shown that a difference still smaller than this will lead to wildly and unpredictably different outcomes in the future evolution of the system. If you say, well, let’s make the specification of initial conditions more precise to overcome this divergence the same phenomenon can then be shown for a still smaller difference in initial conditions and so on (this whole notion can be made mathematically precise).
Chaos theory is one of the components which have provided the basis for more recent new developments which are some of the most exciting in science for many years. These have been dubbed ‘the science of complexity’.
These developments also draw on new developments in thermodynamics, the science of processes involving heat. Thermodynamics has long sat uneasily alongside other areas of physics. It originated in the work of scientists like Sadi Carnot in the early years of the 19th century and grew directly out of attempts to understand what were the scientific principles underlying the steam engines that were playing a key role in the industrial revolution. Thermodynamics soon began to pose problems as it seemed quite different to the understanding developed in most of the rest of physics. For instance, whereas, say, Newtonian science was deterministic, the laws of thermodynamics were probabilistic.
Secondly, Newtonian science was strictly time reversible. This means that there is nothing in, say, Newton’s laws of motion to distinguish changes running forwards or backwards in time. Put crudely a movie of a strictly Newtonian world would not look wrong if it were run backwards. The obvious problem is of course that most real processes in the world are not reversible – try unbreaking an egg or unstirring the milk from your coffee. Thermodynamics deals with such irreversible changes, heat flows from hot to cold, never the other way around. Time, and development in a definite direction in time, plays a key role in thermodynamics, in a way that is not true of most of the rest of the laws of physics.
In short, thermodynamics was not easily reconciled with the laws thought to govern the particles or molecules of which something was composed. This was not helped much even with the scientific revolution of relativity and quantum mechanics – both are still time reversible in the sense described above. In addition most thermodynamic theory was developed around understanding processes involving heat which were near a stable equilibrium – mainly because this was mathematically easier. 
In recent years however scientists like the Belgian Nobel Prize winner Ilya Prigogine have started to study thermodynamics when processes are far from equilibrium – which is much more typical of the real world. Other scientists have built on this kind of work and elements of chaos theory to try and look at the connections between different aspects of nature, and in particular to seek to understand the dynamics, the processes of change, which underlie complex physical systems in general, to try and understand the common patterns. It is an attempt, though most of the scientists involved would not use such language, to develop a ‘dialectics of nature’.
One of the key notions these scientists have developed is that of emergent properties in complex systems. They point to, and seek to explain, how matter itself at certain levels of complexity develops new behaviour which grows out of the underlying laws, but cannot be simply reduced to these underlying laws. It requires an understanding on that new level.
A picture of nature is beginning to emerge in which at certain points physical systems not only can undergo a transition from regular ordered behaviour to chaotic unpredictable behaviour, but of how matter, once it reaches a certain level of complexity of organisation, can spontaneously generate new higher forms of ordered behaviour. It is a picture of potential development in nature whose essence is exactly that which Engels was grappling with in his discussion of the ‘negation of the negation’. Some physical systems can be pushed from a stable ordered state into a chaotic state by some pressure, change or impulse (it is ‘negated’). But under certain conditions some of these systems can then develop in such a way as to give rise to new higher forms of ordered behaviour, often with novel properties (the ‘negation is negated’).
This kind of pattern seems to be typical of many complex systems in nature and scientists are now beginning to seek to understand it. There is some evidence, though it is not established, that complex organisations of matter with genuinely novel and ‘creative’ properties are those ‘on the edge of chaos’, systems balanced in a dynamic tension between the tendency towards a dead, stable, repetitive order on the one hand and an unpredictable, disordered, chaotic state on the other. 
Where these developments will lead no one yet knows, though one can be certain there will be as much abuse of them as there has been of almost every new scientific development from Darwin to chaos theory. Phil Anderson, who won a Nobel Prize for his work on what is called condensed matter physics, is one of those involved in developing some of this work. He points to the potential of the new science which is beginning to show how ‘at each level of complexity entirely new properties appear. And at each stage entirely new laws, concepts and generalisations are necessary. Psychology is not applied biology, nor is biology, chemistry’. 
Anderson gives a simple but illustrative example of the point from everyday experience – water. A water molecule is not very complicated: one big oxygen atom with two smaller hydrogen atoms stuck to it. Its behaviour is governed by well understood laws and precise equations of atomic physics. But if a few billion of these molecules are put together they collectively acquire a new property that none of them possesses alone, liquidity. Nothing in the underlying laws governing the behaviour of the individual atoms tells you about this new property. The liquidity is ‘emergent’. In turn, argues Anderson, this ‘emergent property’ produces ‘emergent behaviour’. The liquidity can, through cooling, suddenly be transformed into the solid, crystalline structure of ice. Again this behaviour simply has no meaning for an individual water molecule alone.
Further simple examples, by way of illustration, occur with the onset of convection when heating a fluid such as water. At first the heat rises through the fluid by conduction. At a certain critical point, however, and under certain conditions, an abrupt qualitative change in behaviour occurs. Suddenly millions of molecules switch into large scale – by molecular standards – coherent motion in hexagonal convection cells, known as Bénard cells. Again certain chemical reactions exhibit this kind of spontaneous emergence of structure or order. In these ‘chemical clocks’ millions of molecules undergo rhythmic and structured transformations on a vast scale – again relative to the molecular scale at which the underlying reactions take place. These are examples of what is possible in relatively simple physical systems. The possibilities in more complex systems are correspondingly richer.
The kind of understanding Anderson and similar scientists are beginning to develop is exactly what Engels meant by a dialectical understanding of the change of quantity into quality. It is an understanding which shows how matter itself, through interactions among different facets of the same totality (all have evolved historically from the seemingly undifferentiated and homogenous early universe), is qualitatively transformed and develops through history.
It remains true that modern science continues to throw up as many questions as it answers, but just because new questions are posed should not lead us to ignore the many and important answers found over the last century. No doubt some of the various hypotheses put forward today to explain aspects of nature will, as Engels put it ‘be weeded out by experience’. Some severe weeding will surely be necessary since, as always in the history of science, theories which explain various parts of nature are riddled with problems and are often mutually incompatible. Quantum mechanics and general relativity, for instance, seem to be incompatible at a fundamental level. Again non-linear processes are increasingly seen as vital in an understanding of nature, but while general relativity and chaos theory are radically non-linear, quantum theory is not. All three are time reversible, in the sense explained earlier, yet the new thermodynamics, not to mention the real world, points to the fundamental importance of irreversible processes in nature. 
Which aspects of existing and any new theories are correct, which only of limited value, and which figments of the imagination will become clear when we find a way to tease the answers out of the only ultimate arbiter – matter, in all its many aspects and changes. Lenin, the leader of the 1917 Russian Revolution, in commenting on the scientific revolution of his day put the argument well:
Our knowledge is penetrating deeper, properties of matter are disappearing which formerly seemed absolute, and which are now revealed to be relative and characteristic only of certain states of matter. The sole property of matter with whose recognition philosophical materialism is bound up is the property of being an objective reality, of existing outside our mind. 
I have already pointed to the way some leading biologists consciously draw on the tradition founded by Engels. Today some physicists and scientists in other fields are also beginning to recognise the connection between the way they are pushed to think and the approach advocated by Engels. Ilya Prigogine, who has played a key role in the new thermodynamics, for instance says, ‘To a certain extent there is an analogy’ between the problems he is grappling with and ‘dialectical materialism’.
And he says the key understanding emerging from modern scientific developments is that ‘nature might be called historical, that is, capable of development and innovation.’ And he goes on to comment:
The idea of a history of nature as an integral part of materialism was asserted by Marx and in greater detail by Engels. Contemporary developments in physics have thus raised within the natural sciences a question that has long been asked by materialists. 
Richard Levins and Richard Lewontin dedicated their 1985 book The Dialectical Biologist, ‘To Frederick Engels, who got it wrong a lot of the time but who got it right where it counted’. 
Many scientists will say they have no need of philosophy to make sense of nature, that they are simply discovering how nature works. So be it. The science will ultimately stand or fall on its truth, its success in practice, whatever the thoughts in the heads of the scientists or anyone else.
But it is worth noting the dangers many modern physicists, or at least those who think about the meaning of the science they produce, fall into when they reject an attempt to have a consistent materialist, dialectical approach. I quoted earlier physicist Paul Davies’s book The Mind of God and its talk of possibly needing to embrace ‘the mystical path’. He is certainly not alone in such thoughts. Physicist Stephen Hawking concludes his otherwise excellent best seller, A Brief History of Time, by talking of ‘the ultimate triumph of human reason’ as ‘to know the Mind of God’.  Even Ilya Prigogine ends a generally marvellous book with stuff like ‘time is a construction and therefore carries an ethical responsibility’ and references to the ‘God of Genesis’.  It is worth recalling Engels’ warning against the illusion that science can do without philosophy and the dangers into which ‘sober headed empiricists’ can fall. 
It should be clear that Engels’ general approach to and arguments about science were correct and stand up well against the scientific developments in the 100 years since his death. In fact those developments are a powerful argument for the necessity of a dialectical understanding of nature.
What are the key elements in such an understanding? The first is that nature is historical at every level. No aspect of nature simply exists: it has a history, it comes into being, changes and develops, is transformed, and, finally, ceases to exist. Aspects of nature may appear to be fixed, stable, in a state of equilibrium for a shorter or longer time, but none is permanently so. This is the inescapable conclusion of modern science. Instead of expecting constancy or equilibrium as the normal condition a dialectical approach means expecting change but accepting apparent constancy within certain limits.
The second key element on which Engels was right is the need to see the interconnections of different aspects of nature. Of course it is necessary to break nature up, isolate this or that aspect, in order to understand and explain. But this is only part of the story, and unless complemented by seeing whatever parts have been isolated for study in their interconnections and relationships leads to a one sided, limited understanding. Parts only have full meaning in relation to the whole. This is not any kind of argument for a mystical ‘holism’. The real relationships between different aspects of nature must be established and worked out scientifically. It is simply an insistence that such investigation is necessary for a full understanding to be established.
As in most questions there is a connection between the way nature is viewed and the dominant ideology in society. The fact that a way of thinking about nature in which equilibrium is the norm and in which the focus is on isolated parts, ‘atoms’, is typical is no accident in modern capitalist society. Though originally revolutionary, the capitalist class now has to believe – and tell us to believe – that its way of organising society is best. It has to suggest, whatever the daily accumulating evidence to the contrary, that stability and equilibrium are the normal conditions. It has to suggest that there is no reason why the current way of running society need change radically. Its vision of society is precisely one of atomised individual units. The family, the individual, are paramount. ‘There is no such thing as society,’ as Margaret Thatcher argued. When this is the dominant ideology in society it is no surprise that it often influences the way scientists think about nature.
What of the general patterns, ‘laws’, which Engels argued characterise processes of change and development in nature? I would argue that there is no question that Engels’ arguments about quantitative change giving rise at certain points to qualitative transformations are generally correct. In every field of science, every aspect of nature, one cannot but be struck by precisely this process. Any attempt to understand the natural world which does not expect this to be a typical feature of change and development cannot be reconciled with the developments of modern science. Of course to expect such patterns of change does not tell you anything at all about the specific nature of real processes. The natural world has to be investigated and its behaviour established and explained scientifically.
A consequence of this view, however, is the understanding, more and more supported by modern science, that a radically anti-reductionist view of nature is necessary. As quantitative change gives rise to qualitative transformation, new organisations of matter arise. These have genuinely novel ways of behaving which, while compatible with the laws governing the underlying components, are not simply reducible to them. Biology is not simply applied physics and chemistry. Nor are human behaviour and consciousness simply applied molecular biology. Still less are politics, economics and history applied biology. An understanding is necessary which sees the connections between all these different levels of the organisation of matter, for they are all the result of nothing more than the greater or lesser complexity of organisation of matter – there are no mystical or vital principles at work. But an understanding of nature is also necessary which sees that each level has its own laws, ways of behaving, which cannot be read off from the laws governing a different level.
Throughout nature it seems that things which appear to have any persistence, any stability, for a greater or shorter time, are the result of a temporary dynamic balance between opposing or contradictory tendencies. This is as true of simple physical objects like atoms as of living organisms. When that balance is broken – as it always is at some point – change can result which leads to a new development, a transformation to a new situation which is not simply a disintegration or a circular recreation of what was there before. But this is a potential, a possibility, rather than a general feature. Furthermore the way changes take place, and the kinds of possibilities, tendencies or patterns that can occur are different at different levels of the organisation of matter.
This is especially true of the kinds of processes which Engels talks of as examples of ‘negation of the negation’. It seems to have little validity when talking of change in simple physical objects. It becomes important when talking of more complex persistent systems which have the capacity when absorbing impulses to preserve, and possibly transform, themselves. So it fits much better when looking at biological organisms, whose condition of existence is precisely the continual absorption and transformation of external matter. It is even more apparent in the subclass of living bodies who have reached the further stage of development of consciousness and then self consciousness. These are constantly under the influence of external causation (they are being negated) but by becoming aware of this have the possibility of incorporating it under their own control (above all at the collective, social level) and in the process transforming themselves, and their relations with the external world. Living organisms open up kinds of development, processes of change, which are not there in the same form in the non-living world. Even more so is it the case that with the emergence of human consciousness and society new patterns of development and change become possible.
In addition, though, the concept is also important when looking at the evolution of the totality of matter itself. All these various levels of the organisation of matter are different facets of the same material totality, which though differentiated has an underlying unity. This totality has developed to give rise to the different patterns of change exhibited at different levels of the organisation, and stages of the history, of the natural world. The levels and the patterns of change open at each are different, but they are connected aspects of the underlying unity.
A genuine dialectical view of nature would require the investigation of all these issues, a study of processes of change and development at every level of nature, their similarities and their differences. To construct such an understanding, based firmly on the real results of a developing scientific understanding of nature, would be the best tribute to Engels’ pioneering work which still remains by far the best starting point for the philosophy of science. Engels’ arguments on science have for too long been ignored, dismissed or distorted – by socialists sometimes as much as by others. One hundred years after his death it is time that changed. But in learning from Engels and seeking to build on his insights we should do so in the spirit in which he himself worked: ‘How young the whole of human history is, and how ridiculous it would be to attempt to ascribe any absolute validity to our present views’. 
1. Quoted in preface to Engels, The Dialectics of Nature (Moscow 1982), p. 6.
2. The notes which form The Dialectics of Nature were not published until 1927, many years after Engels’ death.
3. H. Sheehan, Marxism and the Philosophy of Science (New Jersey 1993), p. 29. This book is a useful guide to the arguments within the Marxist tradition on science.
4. Ibid., p. 30.
5. For instance, far from the rigid, mechanical deterministic view Engels is often attacked for, he time and again attacks such an approach. Indeed this is so much the case that one is often forced to wonder if these critics have ever actually read Engels! Rigid determinism in natural science in the 19th century was best summed up by the French scientist Pierre Laplace. He claimed that the result of modern science was an all embracing determinism in which the past, present and future down to the smallest detail were all equally and completely determined.
Such ‘Determinism’, Engels argued, ‘tries to dispose of chance by denying it altogether. According to this conception only simple, direct necessity prevails in nature.’ He mocks this view:
‘That a particular pea-pod contains five peas and not four or six, that a particular dog’s tail is five inches long and not a whit longer or shorter, that this year a particular clover flower was fertilised by a bee and another not, and indeed by precisely one particular bee and at a particular time, that a particular windblown dandelion seed has sprouted and another not, that last night I was bitten by a flea at four o’clock in the morning, and not at three or five o’clock, and on the right shoulder and not on the left calf – these are all facts which have been produced by an irrevocable concatenation of cause and effect, by an unshatterable necessity of such a nature indeed that the gaseous sphere, from which the solar system was derived, was already so constituted that these events had to happen this and not otherwise. With this kind of necessity we likewise do not get away from the theological conception of nature. Whether with Augustine and Calvin we call it the eternal decree of God, or Kismet as the Turks do, or whether we call it necessity, is all pretty much the same’ (The Dialectics of Nature, p. 499).
6. H. Sheehan, op. cit., also defends Engels well from some of the attacks he has suffered.
7. F. Engels, The Dialectics of Nature in Marx, Engels, Collected Works (MECW), Vol. 25 (London 1987), p. 319.
8. Ibid., p. 320.
9. His explanation, which drew on work on magnetism by Gilbert, was wrong, but the attempt was important. Until then a central belief in all explanations of nature was the sharp distinction between the Moon and the Earth and the rest of the heavens, the ‘sublunary’ and ‘superlunary’ spheres in the language of the day. This distinction was based on the authority of Aristotle, who had been adopted by the Catholic Church, the key ideological authority in feudal society, for its own purposes. In the superlunary sphere, the world of the planets and stars, everything was perfect, unblemished and unchanging, everything was supposed to move endlessly in perfect circles. Change, decay, transformation were the preserve of the ‘corrupt’ sublunary sphere, i.e. Earth and its immediate environment. Kepler’s arguments were therefore a challenge to this central doctrine of the old world view. Galileo’s findings with the telescope must also be seen in this context to appreciate their revolutionary nature.
10. Engels, The Dialectics of Nature, MECW, op. cit., p. 465.
11. Ibid., p. 466.
12. Ibid., p. 466.
13. Ibid., p. 466. For one period of history Boris Hessen fulfilled Engels’ hope. Hessen’s account of the relationship between the development of Newton’s science and social and production developments is a masterpiece. See The Social and Economic Roots of Newton’s Principia in Science at the Crossroads: Papers presented to the International Congress of the History of Science and Technology, held in London from 29 June to 3 July 1931, by the delegates of the USSR (London 1971). Hessen disappeared in the Stalinist purges in the USSR in the 1930s.
14. Ibid., p. 321.
15. Ibid., pp. 321–322.
16. Ibid., p. 322.
17. Ibid., p. 322.
18. Ibid., p. 322.
19. Ibid., p. 322. Newton’s theory explained the motion of the planets once they were moving, he required a ‘first impulse’ (i.e. god) to set the whole mechanism in motion.
20. Engels, Anti-Dühring, MECW, Vol. 25, op. cit., p. 25.
21. Engels, The Dialectics of Nature, MECW, op. cit., p. 324.
22. Ibid., p. 323.
23. Ibid., p. 324.
24. Ibid., p. 324.
25. Ibid., p. 324.
26. Ibid., p. 325.
27. See a description of this process by one of the key founders of thermodynamics in Reflexions on the Motive Power of Fire by Sadi Carnot, translated and edited (with excellent and fascinating notes) by R. Fox (Manchester University Press 1986).
28. Engels, The Dialectics of Nature, MECW, op. cit.. p. 325.
29. Ibid., p. 325.
30. Ibid., p. 326.
31. Ibid., p. 326.
32. Quoted in H. Sheehan, op. cit., p. 38.
33. Engels, The Dialectics of Nature, MECW, op. cit., p. 327.
34. K. Marx and F. Engels, Communist Manifesto, Marx Engels Selected Works, Vol. I (Moscow 1977), p. 111.
36. Engels, The Dialectics of Nature, MECW, op. cit., p. 327.
37. Ibid., p. 327.
38. Engels, Anti-Dühring, MECW, op. cit., p. 21.
39. Ibid., p. 22.
40. Ibid., p. 22.
41. Engels, The Dialectics of Nature, MECW, op. cit., p. 353.
42. Ibid., p. 491.
43. Engels, Anti-Dühring, MECW, op. cit., p. 22.
44. Ibid., p. 22.
45. Ibid., p. 22.
46. Ibid., pp. 22–23.
47. Ibid., p. 23.
48. Engels, The Dialectics of Nature, MECW, op. cit., p. 495.
49. Ibid., p. 515.
50. Ibid., pp. 515–516.
51. Engels, Anti-Dühring, MECW, op. cit., p. 23.
52. Engels, The Dialectics of Nature, MECW, op. cit., p. 356.
53. Ibid., pp. 342–343. Engels tackles many arguments about what is ‘scientific method’. In doing so he challenges many of the then fashionable arguments in a way that was decades in advance of his time. This is especially relevant given that at the time of writing Karl Popper, the famous philosopher of science, has recently died. Popper, especially through his Logic of Scientific Discovery, had been one of the most influential philosophers of science of the last few decades, and there is much in his arguments that is important.
Few of those who study or follow Popper have probably ever bothered to read Engels. Popper himself was a bitter – if shallow – opponent of Marxism. It is therefore amusing that many of Popper’s most original insights about science were precisely those to which Engels had pointed. Popper attacked the traditional empiricist view of science as the gradual accumulation of secure facts, with theories then being developed by induction from these facts and verified through experiment. Instead Popper argued that even the most straightforward observation of nature contains irreducible elements of theory – all observation is ‘theory laden’. Engels makes precisely this point in a sharp attack on empiricism: ‘However great one’s contempt for all theoretical thought, nevertheless one cannot bring two natural facts into relation with each other, or understand the connection existing between them, without theoretical thought’ (The Dialectics of Nature, p. 354).
Again Popper attacked the notion that scientific theories are constructed by induction from empirical facts. Rather he argued that science develops through the formation of bold conjectures, or hypotheses, which may not be based on facts but which can be tested experimentally. Moreover, far from verifying theory, the point of these tests was to falsify wrong theories. Scientific theories had to be open to falsification; hypotheses were to be refuted by experience. Much of this approach can be found in outline in Engels’ work. He called induction ‘a swindle’. ‘According to the inductionists, induction is an infallible method. It is so little so that its apparently surest results are every day overthrown by new discoveries’ (Engels, The Dialectics of Nature, p. 508). And he gives example after example of how theories had been refuted by new facts. Engels also pointed out the logical problem with induction, in precisely an example found in Popper, that ‘it does not follow from the continual rising of the sun in the morning that it will rise again tomorrow’ (Engels, The Dialectics of Nature, p. 510). And Engels draws the conclusion, ‘The form of development of natural science, in so far as it thinks, is the hypothesis’, and that science develops as ‘observational material weeds out these hypotheses’ (The Dialectics of Nature, p. 529, emphasis in Engels’ original).
Critics of Engels often argue that dialectics denies the validity of formal logic. This is simply not true. Dialectics is rather a critique of the limits of formal logic. Such logic is invaluable, but is not capable of fully grasping a dynamic, changing world. (It is interesting to note in this context that some logicians today are seeking to develop new kinds of logic based upon the quantum mechanical nature of reality – which does not easily fit the categories of traditional logic.)
In later years Engels’ ideas on dialectics were distorted out of all recognition by official Stalinist philosophers of states like the USSR, China and the old regimes in Eastern Europe. This has sometime led many genuine Marxists who opposed these regimes to be suspicious of talk of ‘dialectics’. This, however understandable its motives, is mistaken. These regimes turned every aspect of genuine Marxism on its head in a grotesque parody aimed at legitimising their own rule and exploitation of workers. Genuine Marxists have always had to rescue the real meaning of Marxism from such distortions and insist on its continued relevance. The same approach should be adopted with Engels’ arguments on dialectics.
54. Engels, The Dialectics of Nature, MECW, op. cit., p. 356.
55. Ibid., p. 357.
56. Ibid., p. 359.
57. Ibid., p. 359.
58. Ibid., p. 359.
59. Ibid., p. 361.
60. Ibid., p. 357.
61. Ibid., p. 492.
62. Engels, Anti-Dühring, MECW, op. cit., p. 130.
63. Ibid., pp. 76–77.
64. Ibid., p. 130.
65. Engels, The Dialectics of Nature, in MECW, op. cit., p. 587.
66. Engels, Anti-Dühring, MECW, op. cit., p. 24.
67. Engels, The Dialectics of Nature, MECW, op. cit., p. 321.
68. S. Rose, R. Lewontin and L. Kamin, Not In Our Genes (Penguin 1984); S. Rose, The Making of Memory (London 1992); R. Lewontin, The Doctrine of DNA (London 1993); R. Levins and R. Lewontin, The Dialectical Biologist (Harvard University Press 1985). Why biologists are more inclined to a dialectical approach than most other scientists is an interesting question. I suspect it is a result of a combination of factors. One is that the scientific material itself more clearly pushes biologists towards a dialectical understanding. Secondly, political and philosophical argument is forced upon biologists in a far sharper way than in many sciences, given, for example, arguments about human nature etc. Thirdly, the fact that a number of the individual biologists concerned have at various points been connected to Marxist political traditions, and more so than in, say, physics, must play a part.
69. P. Davies, The Mind of God (London 1992), pp. 231–232. To be fair to Davies he is one of the few writers on modern physics who asks the right questions. Most of his attack on materialism is in fact a well justified refutation of mechanical materialism. The thrust of much of this is little different from Engels’ own arguments. I do not know if Davies has ever read Engels. Unfortunately, whether through ignorance of this tradition or otherwise, Davies’s correct rejection of mechanical materialism leads him to mistakenly reject genuine materialism.
70. P. Davies and J. Gribbin, The Matter Myth (London, 1991), p. 7.
71. Ibid., p. 8.
72. Engels, The Dialectics of Nature, MECW, op. cit., p. 527.
73. Good discussions of the problems and interesting suggestions of possible solutions, written in a fairly non-technical fashion, can be found, for example, in P. Coveney and R. Highfield, The Arrow of Time (London 1991), and M. Gell-Mann, The Quark and the Jaguar (Little Brown 1994). Some of the problems are beginning to be resolved in the most convincing way by a new generation of fascinating experiments, many centred in France under scientists like Serge Haroche. They are beginning to demonstrate how the transition from the strangeness of the quantum mechanical behaviour of atomic objects to the more familiar behaviour of larger scale objects takes place. (Lecture by Serge Haroche, Royal Society, London, October 1994.)
74. This was the theme of a major article in the March 1994 edition of the reputable Scientific American magazine, for instance.
75. Quoted in The Arrow of Time, op. cit..
76. H. Sheehan, op. cit., p. 31.
77. Ibid., p. 319.
78. The whole of the October 1994 issue of the excellent Scientific American magazine is devoted to an overview of this whole process through its various stages. On reading through this after reading Engels one cannot help feeling that it should have been dedicated to his memory. In passing it is worth saying that the ‘big bang’ model has its own limitations. It is only valid up to a point. The laws of physics in their present form break down at the very high energies and densities as we try and track evolution back towards the ‘bang’. No one can yet trace that development back beyond a certain point as a result. On the same theme even the fundamental principle of the conservation of energy is only strictly valid within certain limits. It is now established that it can be violated provided the time scale involved in the violation is small enough – as a consequence of the uncertainty principle of quantum mechanics.
79. It is misleading, as is often suggested, to say the butterfly alone ‘causes’ the hurricane. The real point is that a tiny change in the totality of causes can result in radically different outcomes.
80. One interesting aspect of chaos theory is that the old notions about dimensions have had to be radically changed. Usually one thinks of something having one (a line), two (a surface) or three (a solid) dimensions. In chaos theory this understanding is shown to be limited and insufficient to grasp reality. Objects can have fractional dimensions (e.g. 1.57). The beautiful pictures often seen in books on chaos are of such ‘fractals’.
81. For a fuller discussion of chaos theory see my Order out of Chaos, International Socialism 48, 1990. Also see, for instance, I. Stewart, Does God Play Dice? (Basil Blackwell 1989); J. Gleick, Chaos: Making a New Science (Sphere 1988).
82. Thermodynamics and classical dynamics can be reconciled (via statistical mechanics) for systems at, or near, equilibrium. But this reconciliation breaks down for systems far from thermodynamic equilibrium. Engels’ discussion of mathematics, of which he had a good knowledge and keen interest, is another important aspect of his work. His attitude is refreshing compared to much modern philosophical discussion on mathematics. All too often such discussion sees mathematical concepts as either simply the free creation of the human mind, completely divorced from the real world, or as existing independently of the material world or human thought in some ‘timeless, etherial sense’. This is the view of the leading mathematician Roger Penrose (see R. Penrose, The Emperor’s New Mind, London 1990). In this view, known as Platonism, as the notion has much in common with arguments advanced by the ancient Greek philosopher, these eternal concepts exist ‘out there’ as much as ‘Mount Everest’ (Penrose, p. xv) and are ‘discovered’ when mathematicians succeed in breaking through to this ‘Platonic’ world by an act of insight or when they ‘have stumbled across the “works of God”.’ (Penrose, p. 126)
In contrast to such approaches, Engels insists that mathematical concepts are rooted in the material world. ‘The concepts of number and figure have not been derived from any source other than the world of reality’ (Anti-Dühring, op. cit., p. 36). For instance, ‘Counting requires not only objects that can be counted, but also the ability to exclude all properties of the objects considered except their number – and this ability is the product of a long historical development based on experience. Like the idea of number, so the idea of figure is borrowed exclusively from the external world and does not arise in the mind out of pure thought. There must have been things which had shape and whose shapes were compared before anyone could arrive at the idea of figure.
‘Pure mathematics deals with the space forms and quantity relations of the real world – that is with material which is very real indeed. The fact that this material appears in an extremely abstract form can only superficially conceal its origin from the external world.’ (Anti-Dühring, op. cit., pp. 36–37)
Though Engels insists mathematics is in this way rooted in the real world, it is not simply a reflection of it but rather an abstraction from it: ‘In order to make it possible to investigate these forms and relations in their pure state, it is necessary to separate them entirely from their content, to put the content aside as irrelevant, thus we get points without dimensions, lines without breadth and thickness, a and b, x and y, constants and variables; and only at the very end do we reach the free creations and imaginations of the mind itself, that is to say imaginary magnitudes.’ Engels was certainly not arguing that mathematical concepts did not soar far away from their material origins as they were developed. He attacked, for instance, those who were unhappy with the idea of what mathematicians call imaginary numbers – like ι, the square root of −1.
Engels went on to comment on the problem of why it is that ‘pure’ mathematics can be ‘applied’ to the real world – a problem which has long exercised philosophers of mathematics.
‘Like all other sciences, mathematics arose out of the needs of men … but, as in every department of thought, at a certain stage of development the laws, which were abstracted from the real world, become divorced from the real world, and are set up against it as something independent, as laws coming from the outside, to which the world has to conform.
‘In this way … pure mathematics was subsequently applied to the world, although it is borrowed from this same world and represents only one part of its forms of interconnection – and it is only just because of this that it can be applied at all.’ (Anti-Dühring, op. cit., p. 37)
Engels’ comments are certainly a long way short of a fully worked out philosophy of mathematics but they contain much that provides a useful starting point in any serious attempt to construct such an understanding.
83. See for a discussion of all these points, for example: The Arrow of Time, op. cit., M. Mitchell Waldrop, Complexity (Viking 1993), and I. Prigogine and I. Stengers, Order out of Chaos (Flamingo 1985).
84. Quoted in M. Mitchell Waldrop, op. cit., p. 82. Anderson won his Nobel Prize in 1977 for his detailed explanation of a marvellously dialectical process in nature. Metals are either conductors or insulators of electricity. But it was then found that certain metals could undergo a transition from being a conductor into an insulator. Anderson explained how this startling transformation happened.
85. In fundamental particle physics many of the theories put forward today to overcome some of the difficulties with existing explanations combine two elements. On the one hand they often seem to contain genuine insights which will one day have to be incorporated into any new understanding. But on the other they are often riddled with fanciful notions and wild flights of speculation which are far removed from any meaningful contact with any aspect of the world open to us at present – and very often even the advocates of these theories are not sure what they are really talking about.
A good example is the latest attempt to reconcile quantum theory with gravity-string theory. This seems to have genuine insight. All previous attempts have been plagued by infinite quantities which occur in the mathematical descriptions and which make a nonsense of them. The easiest way to picture why these arise is to recall that in, for example, gravity the force changes in inverse proportion to the square of the distance – 1/r². In established explanations particles like, for instance, electrons are pictured as being point-like, having no extension. Think what happens to an expression like 1/r² when r becomes zero. In a more complicated but analogous manner many of the fundamental problems in modern science are rooted in the very notion of point-like particles which dominates physics. String theory gets rid of these infinities and for the first time seems to point to a genuine reconciliation of quantum theory and gravity. The key element is that it sees particles not as point-like objects but rather as two dimensional ‘strings’, with energies and masses of different particles being analogous to various ‘harmonics’ on a guitar string. The problem, however, is that the whole theory only makes sense in a ‘space’ of ten dimensions which somehow is structured in such a way that we only see the three dimensions of everyday experience. The theory seems to be saying the essence of reality is a ten dimensional space, but the appearance is three dimensions of everyday experience. There are severe problems with this notion. One, for instance, is that some key mathematical structures vital to explaining the world are only valid in a space of three dimensions. In consequence no one, including its inventors, is sure what string theory means, or how real the extra dimensions are supposed to be. And as yet no one has found a way to extract from it testable consequences. Is it the starting point of a new understanding or a flight of speculation that will turn out to have no connection with the way the world really is? (For a discussion of string theory see F. David Pleat, Superstrings, Cardinal 1988).
86. V.I. Lenin, Materialism and Empirio-Criticism (Peking 1972), p. 311.
87. I. Prigogine and I. Stengers, Order out of Chaos (London 1988), p. 252.
88. R. Levins and R. Lewontin, The Dialectical Biologist (Harvard University Press 1985).
89. S. Hawking, A Brief History of Time (Bantam 1989), p. 175.
90. I. Prigogine and I. Stengers, op. cit., p. 313.
91. For a more detailed discussion of the ideas of modern science covered in this section the following references are a good starting point. One of the best is undoubtedly P. Coveney and R. Highfield, The Arrow of Time, which covers almost all the ground discussed here. Also useful are M. Mitchell Waldrop, Complexity, I. Prigogine and I. Stengers, Order out of Chaos, and M. Gell-Mann, The Quark and the Jaguar. Those interested can find further references in these works. All require effort but none require a formal mathematical or scientific training to understand. Anyone wanting to go into the arguments in a more detailed fashion could try the fairly comprehensive collection of essays, P. Davies (ed.), The New Physics (Cambridge University Press 1989) – many, but not all, of these require a fairly good knowledge of mathematics.
92. Engels, Anti-Dühring, MECW, op. cit., p. 106.
Last updated on 19.3.2012