The starting point
I first started work on The History of Philosophy some twenty-seven years ago, when writing Reason in Revolt, a book that dealt with the relationship between Marxist philosophy and modern science. The book was a big success, but it turned out to be much longer than I had originally anticipated. Due to considerations of length, I was reluctantly obliged to omit the first part, which dealt with the history of philosophy, leading up to Marx’s great revolution, the theory of dialectical materialism.
The intention had been to publish The History of Philosophy as a separate work sometime in the future. But for different reasons, that decision was delayed to make way for more pressing tasks. For more than two decades, the manuscript was put to one side, left to the gnawing criticism of the mice, as Marx once said, referring to the unpublished text of the German Ideology. It was eventually published on our website, and was favourably received, but the original intention of publishing it as a book remained unfulfilled until now.
I owe it to the pressure of a number of comrades with a special interest in philosophy that I have been spurred into action to publish this work. It represents a contribution to the ongoing campaign of the International Marxist Tendency to combat bourgeois ideology and to defend and propagate the ideas of Marxism. This was a timely and necessary decision. At a time when the capitalist system finds itself in a terminal crisis, the bankruptcy of the existing order inevitably finds its expression in an evident decline of every aspect of intellectual life.
This is particularly glaring in the field of philosophy, where bourgeois thought expresses its decay in a most scandalous manner. The struggle for socialism is not confined to politics and economics. It must be carried on at all levels, starting with the level of ideas. If the present work helps to arm the workers and youth in this necessary struggle, my aim will have been achieved.
Those who have read the original manuscript will see that, in all essential points, it has been maintained. But I have revised the text thoroughly with the assistance of comrades, and have added new sections, notably in the chapter on the Middle Ages, and also added a final chapter, which explains why philosophy – at least in the old sense of the word – comes to an end with Marxism.
You may also have noticed that the additional chapter on Indian philosophy that was included as an appendix has been omitted from the present edition, while the chapter on Islamic philosophy has been reduced, dealing mainly with the role it played in the Middle ages. This was neither accidental nor due to any lack of interest on my part. Quite the opposite, in fact. As you will appreciate, the presentation of two-and-a-half millennia of philosophy is a very daunting task, and for reasons of space I was compelled to omit many important aspects of the subject, which had to be stripped of all but the most basic essentials.
The evolution of Oriental philosophy (which would have to encompass Chinese philosophy – a vast topic in itself) proceeded on quite different lines to that of philosophy in the West, which reached its peak in Hegel and culminated in the philosophical revolution brought about by Marx and Engels. To do justice to that subject would have required not merely a huge (and quite unwarranted) expansion of the present book, but would have demanded one or more additional volumes. Therefore, rather than publish an unsatisfactory résumé of quite a complicated subject, which would please nobody, least of all myself, I decided to set this subject to one side, with the intention of perhaps returning to it when the pressure of time and work allows.
What is philosophy?
Marxism began as a philosophy, and the philosophical method of Marxism is of fundamental importance in understanding the ideas of Marx and Engels. But what is philosophy?
Philosophy is a way of thinking, different from the kind of thinking we are used to in ordinary life. It does not confine itself to the immediate questions of daily life but attempts to grapple with the big questions of life and death, the universe, the nature of ideas and matter, and what is good and what is bad. These are issues that ultimately are of great importance to every one of us. Yet they do not normally occupy a central place in the thoughts of most people.
For the whole of history, at least up to the present time, the minds of most men and women have been mainly absorbed by the daily struggle for existence. They are fully occupied with such mundane questions as: will I have a job next week? Will I have enough money to last until the end of the month? Will I have a roof over my head, a school for my children, and so on and so forth.
Yet human thought is capable of far greater things. The history of thought includes the history of art, beginning with the wonderful cave paintings of Lascaux and Altamira; the history of science, which has enabled us to conquer nature and reach out our hands to the stars; and also the history of philosophy, with its many astonishing insights.
Philosophy emerges as soon as men and women begin to try to explain the world without the intervention of supernatural agencies: gods and goddesses and all the rest of the superstitious paraphernalia of religion that have been carried over from the most primitive times. It marks the beginning of a scientific understanding of nature and of ourselves.
A revolutionary world outlook
Marxism is first and foremost a world outlook, or philosophy if you prefer. It has a vast scope. It is a theory of history and of economics, and also a guide to revolutionary action. But where did Marx get his ideas from? They did not drop from the clouds. Marx himself explained that there were three main sources to his ideas: there was English classical bourgeois economics (Adam Smith and David Ricardo), then there were the bold pioneers of utopian socialism: the Frenchmen Saint-Simon and Fourier, and my fellow Welshman Robert Owen.
But the first and most important element in the formative stages of the ideas of Marx and Engels was without doubt German classical philosophy, particularly Hegel. And this, in turn, was the product of a lengthy period of the development of many different schools of philosophical thought. Now, it would be very easy to dismiss, for example, the ideas of the utopian socialists (as Dühring did). But surely it is more appropriate to pay tribute to their remarkable contribution to the history of socialism and to recognise the part their ideas played in the formative stage of Marxism?
I recently re-read parts of Robert Owen and I can tell you that some of his ideas are still quite revolutionary today. Does that mean that, in paying tribute to Owen, we advocate going back to the ideas of utopian socialism? Of course not! But it is impossible to deny that these ideas played an important role in the development of scientific socialism. This is a simple fact.
I have occasionally come across a rather childish prejudice that imagines that everything that came before Marx and Engels can be discarded as conservative and reactionary. It is quite true that not only Hegel but also Adam Smith and Ricardo were ‘upper class thinkers’. Some foolish people imagine that this fact alone would be sufficient to disqualify them as great revolutionary thinkers. It is also true that some of them (though by no means all) held political views that tended towards conservatism, or even reaction. Hegel himself was conservative in his political views, although in his younger years he sympathised with the French Revolution. But that does not alter the fact that his dialectical method contained a very revolutionary element – a fact that was recognised by the reactionary Prussian authorities, who regarded Hegel with suspicion, and even suspected him of atheism and subversive views.
Marx explained long ago that the ruling ideas of every epoch are the ideas of the ruling class. These men represented the most advanced thought of their day and Marx based himself on these ideas. The law of value that was discovered by Adam Smith and developed by Ricardo led directly to Marx’s theory of surplus value, and the idealist dialectic of Hegel led to dialectical materialism. The idea that Marxists can ignore the ideas of the past is as stupid as the prejudice held by some extreme anarchists that, in order to build a new classless society, it is necessary to destroy everything that has gone before and build it anew. This is the distilled essence of utopianism and, if we were to accept it, we would rule out the possibility of carrying out a socialist revolution in practice.
A socialist revolution would not destroy the existing achievements of capitalism but, on the contrary, would build on them, filling them with an entirely different social and class content. The achievements of science and technology would no longer serve the interests of a tiny parasitic ruling class, but would be planned harmoniously in the interests of the whole of society. We will build the new society, using the bricks left over by the old, for the simple reason that no other ready-made bricks exist for the purpose.
In the same way that we would make use of the existing productive forces – the land, the factories, science and technology – inherited from the old society, so we should base ourselves on the most advanced ideas developed in the past. Marxism negated Hegel’s idealism, while simultaneously preserving all that was progressive and revolutionary in his dialectical method. The founders of scientific socialism rescued the dialectic, which in the hands of Hegel was presented in a distorted, idealist guise, and placed it for the first time on a sound materialist foundation. In doing so, they created a powerful weapon for changing society along revolutionary lines.
Why study the history of philosophy?
All the writings of Marx and Engels are based on a definite philosophical method and cannot be understood without it, the method of dialectical materialism. The same is true of the works of Lenin and Trotsky, the most outstanding representatives of Marxist thought in the twentieth century. Dialectics was already known to the ancient Greeks and was later developed by Hegel. The basic ideas of dialectical materialism are not so difficult to grasp. Like all great ideas, they are essentially simple, and they are beautiful in their simplicity.
But all too many who regard themselves as Marxists are content to repeat a few basic ideas without giving any thought to the deeper meaning of what they are saying. Such ‘Marxists’ resemble a young child who has learned to recite the multiplication tables by rote, or rather, a parrot that has learned by imitating human speech to repeat certain sentences, without having the vaguest understanding of their meaning. In order to arrive at a full understanding of dialectical materialism, a great deal of careful study will be necessary. At the moment, I am working on a further comprehensive work on Marxist philosophy, which I hope will help to clarify the more complicated questions involved.
But there is a difficulty involved in the study of philosophy in general, and Marxist philosophy in particular, and one that lies at the heart of the present work. When Marx and Engels wrote about dialectical materialism, they could presuppose a basic knowledge of the history of philosophy on the part of at least the educated reading public of the day. Nowadays, it is impossible to make such an assumption.
Hegel’s ‘History of Philosophy’
I first began reading Hegel’s monumental, three-volume History of Philosophy when I was seventeen years old and still in school. I got through the whole of the first volume and half of the second before going to university. I found it absolutely riveting. Here, before my very eyes was two-and-a-half-thousand years of the most profound human thought, set forth in a compellingly clear and comprehensive dialectical manner.
I still possess several school notebooks full of the notes I made at the time on the History of Philosophy, the Philosophy of History and the Phenomenology of Spirit. I even had a notebook in which I had copied out extensive sections of Hegel’s Shorter Logic from The Encyclopaedia of Philosophical Science. I had searched in vain for a copy of that remarkable work, but when I finally obtained one from a reference library, it turned out to be in the original German! But I was not to be put off by such a detail. At the time, my knowledge of the German language was pretty good, so I set about reading it and taking notes. Unfortunately, that particular notebook got lost in the course of my travels.
That enthusiasm for Hegel has remained with me ever since. What struck me about the History of Philosophy was the highly original way in which Hegel approached the subject. It is presented not as a series of accidental developments, but as an organic whole – a process that evolved through a series of contradictions, in which one set of ideas apparently negates a previous one, leading to an endless spiral of development of human thought.
Of course, one may find fault with Hegel’s idealist approach to the history of philosophy. But the most important thing to see is the dialectical method that characterises all of his works. Where others only saw a mass of unconnected ideas, accidents and individual geniuses, Hegel was the first to see an organic process with a law and an inner logic of its own.
In the development of philosophy through a series of contradictions, Hegel saw not merely a negative process, whereby one set of ideas annihilated another. He understood that this process of negation also implied the preservation of all that was valid and true in previous stages. This idea of negation that at the same time preserves is what he called sublation, and it is expressed in the most sublime language in his introduction to the Phenomenology of Spirit:
The bud disappears when the blossom bursts forth, and one could say that the bud is refuted by the blossom; similarly, when the fruit appears, the blossom is declared to be a false Being-there [form] of the plant, and the fruit replaces the blossom as the truth of the plant. These forms are not only different, they also supplant one another as mutually incompatible. Yet at the same time their ﬂuid nature makes them moments of the organic unity, in which they not only do not conﬂict, but each is as necessary as the other; and this shared necessity alone constitutes the life of the whole.
Engels, commenting on Hegel’s Philosophy of History, said this method represented a colossal step forward:
He was the first to try to demonstrate that there is development, an intrinsic coherence in history, and however strange some things in his philosophy of history may seem to us now, the grandeur of the basic conception is still admirable today, compared both with his predecessors or those who following him ventured to advance general observations on history.
For all its faults, the grandeur of Hegel’s History of Philosophy – its majestic sweep and profound insights – is still a source of wonder and admiration to me to this very day. As for the postmodern critics of Hegel, I will repeat what Lenin once wrote about Rosa Luxemburg, quoting the words of an old Russian proverb: “Eagles may at times fly lower than hens, but hens can never rise to the height of eagles.”
The Marxist view of the history of philosophy
In the present work, I have attempted to make use of Hegel’s innovation, but from a consistently materialist point of view. This is not a history of philosophy in the empirical notion of the word. Neither is it a compendium of all that everyone ever said on philosophy. Whoever seeks to find in this work, for example, a detailed study of Plato’s Republic, will be sadly disappointed. Such a person I must direct to the nearest serious public reference library, where I trust they may find a sufficient number of erudite works that will satisfy their curiosity. This is a history of philosophy in its essence. That is, I have tried to follow the overarching line in the development of thought, which has its own immanent laws.
On the other hand, I fear that my book will not satisfy those mechanical ‘Marxists’ who imagine that it is possible to reduce everything under the sun to the development of the productive forces and/or the class struggle. Of course, in the final analysis, these are the fundamental motor forces of human history and determine the fate of countries, states and empires. But to try to find the explanation of, for example, works of art and music, or the fantastic twists and turns of philosophy and religion by imposing a direct link with this substratum would be a foolish waste of time.
However, insofar as philosophers (like everybody else) can be affected by the general state of society – the rise and fall of the productive forces and the resulting social and political tensions – a relationship can be discernible at certain stages, albeit an indirect one, as my work will point out.
As Engels wrote in a letter to the German economist Conrad Schmidt:
As to the realms of ideology which soar still higher in the air, religion, philosophy, etc., these have a prehistoric stock, found already in existence and taken over in the historic period, of what we should to-day call bunk. These various false conceptions of nature, of man’s own being, of spirits, magic forces, etc., have for the most part only a negative economic basis; but the low economic development of the prehistoric period is supplemented and also partially conditioned and even caused by the false conceptions of nature.
And even though economic necessity was the main driving force of the progressive knowledge of nature and becomes ever more so, it would surely be pedantic to try and find economic causes for all this primitive nonsense. The history of science is the history of the gradual clearing away of this nonsense or of its replacement by fresh but already less absurd nonsense.
The people who deal with this belong in their turn to special spheres in the division of labour and appear to themselves to be working in an independent field. And in so far as they form an independent group within the social division of labour, in so far do their productions, including their errors, react back as an influence upon the whole development of society, even on its economic development.
But all the same they themselves remain under the dominating influence of economic development. In philosophy, for instance, this can be most readily proved in the bourgeois period. Hobbes was the first modern materialist (in the eighteenth-century sense) but he was an absolutist in a period when absolute monarchy was at its height throughout the whole of Europe and when the fight of absolute monarchy versus the people was beginning in England. Locke, both in religion and politics, was the child of the class compromise of 1688. The English deists and their more consistent successors, the French materialists, were the true philosophers of the bourgeoisie, the French even of the bourgeois revolution. The German petty bourgeois runs through German philosophy from Kant to Hegel, sometimes positively and sometimes negatively. But the philosophy of every epoch, since it is a definite sphere in the division of labour, has as its presupposition certain definite intellectual material handed down to it by its predecessors, from which it takes its start.
And that is why economically backward countries can still play first fiddle in philosophy: France in the eighteenth century compared with England, on whose philosophy the French based themselves, and later Germany in comparison with both. But the philosophy both of France and Germany and the general blossoming of literature at that time were also the result of a rising economic development.
I consider the ultimate supremacy of economic development established in these spheres too, but it comes to pass within conditions imposed by the particular sphere itself: in philosophy, for instance, through the operation of economic influences (which again generally only act under political, etc., disguises) upon the existing philosophic material handed down by predecessors.
Here economy creates nothing absolutely new (a novo), but it determines the way in which the existing material of thought is altered and further developed, and that too for the most part indirectly, for it is the political, legal and moral reflexes which exercise the greatest direct influence upon philosophy…
What these gentlemen all lack is dialectic. They never see anything but here cause and there effect. That this is a hollow abstraction, that such metaphysical polar opposites only exist in the real world during crises, while the whole vast process proceeds in the form of interaction (though of very unequal forces, the economic movement being by far the strongest, most elemental and most decisive) and that here everything is relative and nothing is absolute – this they never begin to see. Hegel has never existed for them.
What I have attempted to do here is to draw out the essential and general course of the process of the advancement of knowledge, the full development of which in each epoch of history lays the ground for human thought to move on to the next stage.
The task of Marxists is not to assert and merely dissect every school of thought that ever existed. Rather, it is to draw out from the myriad of conflicting trends and ideas, the essential, rational principles, which have propelled humanity to the stage we are at now. This process has contributed mightily to the enormous advances in science and technology, which in turn lay the basis for humanity’s progression to a qualitatively higher stage of development, under socialism.
The postmodern attitude to the past: Where ignorance is bliss, ’tis folly to be wise
Dialectics has a very long history, beginning with the Greeks, the pre-Socratic philosophers and particularly Heraclitus. It reaches its highest expression in the works of Hegel. But the dominant trend in modern bourgeois philosophy treats all past philosophy with contempt. Not only Marxism but all the great ideas of the past are frivolously dismissed, labelled as ‘metanarratives’ and consigned without a second thought to the dustbin of history.
In the past, when the bourgeoisie was still capable of playing a progressive role, it had a revolutionary ideology. It produced great and original thinkers: Locke and Hobbes, Rousseau and Diderot, and the other revolutionary thinkers of the French Enlightenment: Kant and Hegel, Adam Smith and David Ricardo, Newton and Darwin. But the intellectual production of the bourgeoisie in the period of decline displays all the evidence of advanced senile decay.
There are periods in history that are characterised by moods of pessimism, doubt and despair. In such periods, having lost faith in the existing society and its ideology, people have only two alternatives. One is to challenge the existing order and take the revolutionary road. The other is to turn inwards in a futile attempt to ignore the contradictions in society, seeking personal salvation, either in religion or in extreme philosophical subjectivism.
The old society is dying on its feet, but it refuses stubbornly to accept its fate. Powerful material interests continue to exert a determined effort to prop it up, and they command formidable resources and exert an irresistible influence on every aspect of social and intellectual life. Today, the ideology of the bourgeoisie is in the process of disintegration, not only in the fields of economics and politics but also in that of philosophy. It produces nothing of value. No longer commanding positive support, respect or authority, it emanates negative moods, as a corpse emits a bad odour. These moods inevitably find their expression in the prevailing philosophy. It is impossible to read the barren products of the university philosophy departments without a feeling of tedium and irritation in equal measure. Needless to say, this general retrogression finds its reflection in attitudes towards the history of philosophy.
The bright-eyed young students who enter the philosophy departments with high hopes of enlightenment are either swiftly disenchanted or else dragged into the poisonous cesspool of postmodern gibberish from whence no escape is possible. In either case, they will emerge without ever learning anything of value from the great thinkers of the past. Not content with filling the minds of young people with postmodernist rubbish, the philosophy departments have the audacity to introduce the same garbage into the study of the past. Evidently, the postmodern academic gang do not like to be reminded of the fact that there was once a time when philosophers actually had something profound and important to say about the real world.
The distortion of philosophical history
It was recently pointed out to me that a new (and highly praised) translation of Hegel contains a gross mistranslation from the German, which places the postmodernist terminology in the mouth of that great dialectical thinker. The prestigious new Cambridge University English translation of Hegel’s Science of Logic, which is becoming canonised in universities across the world, consistently translates the German words Denken and Denkend (which in English plainly mean “thought” and “thinking”) as “discourse” and “discursive”.
This is a blatant falsification of Hegel’s ideas and a transgression of all the ethical norms of translation. It is a criminal act of trying to sneak postmodernist subjectivism into Hegel. In defending this choice, the translator George di Giovanni casually asserts without any proof that: “The subject matter of the Logic is not the ‘thing-in-itself’ or its phenomenal manifestations, whether one conceives its ‘in-itself’ as a substance or as freedom, but is discourse itself.”
This is nothing short of a scandal. Yet it has passed unnoticed by the ‘critics’, who are all delighted by the new ‘narrative’. It is an act of vandalism, more or less the equivalent of painting a moustache on the face of the Mona Lisa. This little detail should already put us on our guard.
A false objectivity
I have not the slightest doubt that the cleverdicks of the universities will lose no time in accusing me of presenting a one-sided version of the history of philosophy. To this accusation, I plead guilty. As a committed Marxist, I have every intention of defending a particular philosophical standpoint – that of dialectical materialism.
The university philosophy departments are not ivory towers of knowledge and culture, but merely trenches in the war between the classes. These trenches are carefully disguised with an artfully constructed camouflage of pseudo-scientific false objectivity. But behind this tangled web of lies one always finds material interests, class prejudice, and a cynical defence of the status quo.
The whole history of philosophy has been a constant struggle between two hostile and mutually exclusive viewpoints: philosophical materialism and philosophical idealism. That is to say, the scientific approach and the attempt to drag human consciousness backwards to the world of religious mysticism. Since the field of philosophy has always been divided into a whole series of ‘one-sided versions’, it is utterly impossible to avoid taking the side of one or other of these world views. The only difference between the present author and his critics is that I have been honest enough to declare my interest from the very outset, whereas my critics always hide behind a hypocritical and entirely spurious ‘objectivity’, which merely serves to disguise their partisan views and class standpoint.
To this day, philosophy remains a battle with no holds barred between materialism and idealism, where the enemies of materialism are numerous and have many advantages. But does the fact that one takes up a definite philosophical and political standpoint rule out objectivity? That is an assumption which is contradicted by the facts. That great Marxist Leon Trotsky answered these objections as follows:
In the eyes of a philistine a revolutionary point of view is virtually equivalent to an absence of scientific objectivity. We think just the opposite: only a revolutionist – provided, of course, that he is equipped with the scientific method – is capable of laying bare the objective dynamics of the revolution. Apprehending thought in general is not contemplative, but active. The element of will is indispensable for penetrating the secrets of nature and society. Just as a surgeon, on whose scalpel a human life depends, distinguishes with extreme care between the various tissues of an organism, so a revolutionist, if he has a serious attitude toward his task, is obliged with strict conscientiousness to analyse the structure of society, its functions and reflexes.
A word on my critics
Ever since Marxism emerged as a significant force challenging the existing order, the establishment has been in a perpetual state of war against every aspect of Marxist ideology, starting with dialectical materialism. The very mention of Marxism is guaranteed to provoke a knee-jerk reaction in such circles. ‘Out of date’, ‘unscientific’, ‘disproved long ago’, ‘metaphysics’, and all the rest of the threadbare and tiresome litany of reaction.
I have no doubt that the present work will be greeted by a similar chorus of disapproval. This does not bother me in the slightest. I have listened to the same tedious torrent of abuse for the last six decades, and the arguments of the critics of Marx do not gain any greater strength from being so frequently and monotonously repeated. I understand that my opponents will be offended by this. They will try to disprove my arguments by burrowing through old texts to try to prove that, after all, black is white and white is black. This is quite a natural reaction, since they themselves defend a particular philosophical standpoint, which is totally incompatible with my own. By that I mean the standpoint of philosophical idealism – either the objective or the subjective kind.
I naturally have no objection to this. They have every right to defend whatever mystical and irrational ideas appeal to them. But let them not try to conceal their partiality behind a façade of false objectivity, or attempt to distort the ideas of great thinkers of the past to fit in with their own narrow and reactionary outlook.
Philosophy as a revolutionary weapon
In spite of its aura of lofty superiority and contempt for the class struggle, official philosophy is only one more weapon in the hands of the ruling class, and it is used deliberately in order to confuse and disorient the youth, and divert them from the path of revolution. In the words of old Joseph Dietzgen, philosophy is not a science, but the safeguard against socialism.
In former times, philosophers were rebels, dangerous heretics bent on subverting the existing moral and social order. Socrates was forced to drink hemlock; Spinoza was accused of atheism, excommunicated and reviled; Giordano Bruno was burnt at the stake by the Inquisition; the French philosophes of the eighteenth century prepared the way for the storming of the Bastille. In our own times, however, most people regard philosophy and philosophers with either indifference or contempt, which is richly deserved. But it is a matter of the deepest regret that in turning aside from the present-day philosophical desert, people neglect the great thinkers of the past who, in contrast to the modern pygmies, were giants of human thought.
The old idealist philosophy stubbornly maintained its imaginary independence from social life. To this day, the philosophers of academia claim detachment from the grubby world of real human beings, social life and politics. But this is an illusion. In reality, they merely represent a reflection of that same world, albeit in a mystified form. In the last analysis, whether they are conscious of it or not, the ideas they defend are a thinly disguised defence of the existing society and, at bottom, the most sordid and cynical personal interest.
For my part, I have no intention of dancing a complicated minuet with academics who are guided only by a blind hatred of Marxism and a fervent desire to maintain the status quo. Only by clearing the decks of this ideological garbage can we clear the ground for the successful pursuit of the class struggle. Marxism has a duty to provide a comprehensive alternative to the old and discredited ideas. But we have no right to turn our backs on the great thinkers of the past: the Greeks, Spinoza, the French materialists of the Enlightenment and, above all, Hegel. These were heroic pioneers, who prepared the way for the brilliant achievements of Marxist philosophy, and can rightly be considered as an important part of our revolutionary heritage.
We have a duty to rescue all that was valuable in the history of philosophy, while discarding all that was false, outmoded and useless. Just as the October Revolution, the Paris Commune and the storming of the Bastille pointed the way to the future socialist revolution that will transform the entire world, so the great philosophical battles of the past laid the basis for dialectical materialism – the philosophy of the future. And just as we pay careful attention to the lessons afforded by the class struggles of the past, so we have a duty to study the great battle of ideas that constitutes the essential meaning of the history of philosophy.