The Origins of Modern Science

The progress of civilisation is not wholly a uniform drift towards better things. It may perhaps wear this aspect if we map it on a scale which is large enough. But such broad views obscure the details on which rest our whole understanding of the process. New epochs emerge with comparative suddenness, if we have regard to the scores of thousands of years throughout which the complete history extends. Secluded races suddenly take their places in the main stream of events: technological discoveries transform the mechanism of human life: a primitive art quickly flowers into full satisfaction of some aesthetic craving: great religions in their crusading youth spread through the nations the peace of Heaven and the sword of the Lord.

The progress of civilization is not a steady movement toward better things. It may perhaps look that way if we view it on a large enough scale. But such broad views hide the details on which our whole understanding of the process depends. New eras emerge relatively suddenly, considering the tens of thousands of years covered by the whole of history. Isolated peoples suddenly enter the mainstream of events. Technological discoveries transform the way human life works. A primitive art quickly develops until it fully satisfies an aesthetic longing. Great religions, in their crusading youth, spread the peace of Heaven and the sword of the Lord among nations.

The sixteenth century of our era saw the disruption of Western Christianity and the rise of modern science. It was an age of ferment. Nothing was settled, though much was opened—new worlds and new ideas. In science, Copernicus and Vesalius may be chosen as representative figures: they typify the new cosmology and the scientific emphasis on direct observation. Giordano Bruno was the martyr; but the cause for which he suffered was not that of science, but that of free imaginative speculation. His death in the year 1600 ushered in the first century of modern science in the strict sense of the term. In his execution there was an unconscious symbolism: for the subsequent tone of scientific thought has contained distrust of his type of general speculativeness. The Reformation, for all its importance, may be considered as a domestic affair of the European races. Even the Christianity of the East viewed it with profound disengagement. Furthermore, such disruptions are no new phenomena in the history of Christianity or of other religions. When we project this great revolution upon the whole history of the Christian Church, we cannot look upon it as introducing a new principle into human life. For good or for evil, it was a great transformation of religion; but it was not the coming of religion. It did not itself claim to be so. Reformers maintained that they were only restoring what had been forgotten.

The sixteenth century saw the division of Western Christianity and the rise of modern science. It was an age of upheaval. Nothing was settled, though much was opened up, including new worlds and new ideas. In science, Copernicus and Vesalius may be chosen as representative figures. They stand for the new understanding of the universe and the scientific emphasis on direct observation. Giordano Bruno was the martyr. But the cause for which he suffered was not science, but free imaginative speculation. His death in 1600 marked the beginning of the first century of modern science in the strict sense. His execution had an unintended symbolic meaning. Later scientific thought came to distrust his kind of broad speculation. For all its importance, the Reformation may be considered an internal affair of the European peoples. Even Eastern Christianity viewed it with profound detachment. Moreover, such divisions are not new in the history of Christianity or other religions. When we consider this great revolution in the context of the entire history of the Christian Church, we cannot see it as introducing a new principle into human life. For good or ill, it was a great transformation of religion, but it was not the arrival of religion. The Reformation did not claim to be that. Reformers maintained that they were only restoring what had been forgotten.

It is quite otherwise with the rise of modern science. In every way it contrasts with the contemporary religious movement. The Reformation was a popular uprising, and for a century and a half drenched Europe in blood. The beginnings of the scientific movement were confined to a minority among the intellectual élite. In a generation which saw the Thirty Years’ War and remembered Alva in the Netherlands, the worst that happened to men of science was that Galileo suffered an honourable detention and a mild reproof, before dying peacefully in his bed. The way in which the persecution of Galileo has been remembered is a tribute to the quiet commencement of the most intimate change in outlook which the human race had yet encountered. Since a babe was born in a manger, it may be doubted whether so great a thing has happened with so little stir.

The rise of modern science was quite different. In every way, it contrasted with the religious movement of the same period. The Reformation was a popular uprising that drenched Europe in blood for a century and a half. The scientific movement began among a small minority of the intellectual elite. That generation saw the Thirty Years’ War and remembered Alva in the Netherlands. Yet the worst that happened to men of science was that Galileo was held in honorable detention and mildly rebuked. He then died peacefully in his bed. The way Galileo’s persecution has been remembered shows how quietly a profound change in outlook began. It was the most profound change the human race had yet experienced. Since a baby was born in a manger, it is doubtful whether anything so great has happened with so little commotion.

The thesis which these lectures will illustrate is that this quiet growth of science has practically recoloured our mentality so that modes of thought which in former times were exceptional, are now broadly spread through the educated world. This new colouring of ways of thought had been proceeding slowly for many ages in the European peoples. At last it issued in the rapid development of science; and has thereby strengthened itself by its most obvious application. The new mentality is more important even than the new science and the new technology. It has altered the metaphysical presuppositions and the imaginative contents of our minds; so that now the old stimuli provoke a new response. Perhaps my metaphor of a new colour is too strong. What I mean is just that slightest change of tone which yet makes all the difference. This is exactly illustrated by a sentence from a published letter of that adorable genius, William James. When he was finishing his great treatise on the Principles of Psychology, he wrote to his brother Henry James, ‘I have to forge every sentence in the teeth of irreducible and stubborn facts.’

These lectures will illustrate a central claim. The quiet growth of science has effectively changed the color of our thinking. Ways of thinking that were once exceptional are now widespread among educated people. This change in thought had been taking place slowly among European peoples for many ages. At last, it led to the rapid development of science. Science, the most obvious application of this new way of thinking, then strengthened it. The new mentality is even more important than the new science and technology. It has changed our assumptions about reality and the images in our minds. As a result, the same old stimuli now provoke a new response. Perhaps my metaphor of a new color is too strong. I mean only the slightest change of tone, one that nevertheless makes all the difference. A sentence from a published letter by that adorable genius, William James, illustrates this exactly. As he was finishing his great treatise on the Principles of Psychology, he wrote to his brother Henry James, ‘I have to forge every sentence in the teeth of irreducible and stubborn facts.’

This new tinge to modern minds is a vehement and passionate interest in the relation of general principles to irreducible and stubborn facts. All the world over and at all times there have been practical men, absorbed in ‘irreducible and stubborn facts’: all the world over and at all times there have been men of philosophic temperament who have been absorbed in the weaving of general principles. It is this union of passionate interest in the detailed facts with equal devotion to abstract generalisation which forms the novelty in our present society. Previously it had appeared sporadically and as if by chance. This balance of mind has now become part of the tradition which infects cultivated thought. It is the salt which keeps life sweet. The main business of universities is to transmit this tradition as a widespread inheritance from generation to generation.

What is new in modern minds is a fierce and passionate interest in how general principles relate to irreducible and stubborn facts. Everywhere and at all times, practical people have been absorbed in ‘irreducible and stubborn facts’. Everywhere and at all times, people with a philosophical temperament have been absorbed in weaving general principles. What is new in our society is the union of these interests. We have a passionate interest in detailed facts and an equal devotion to abstract generalization. Before now, this combination appeared only occasionally and as if by chance. This balance of mind has now become part of the tradition that permeates educated thought. It is the salt that keeps life sweet. The main task of universities is to pass this tradition on as a shared inheritance from generation to generation.

Another contrast which singles out science from among the European movements of the sixteenth and seventeenth centuries, is its universality. Modern science was born in Europe, but its home is the whole world. In the last two centuries there has been a long and confused impact of Western modes upon the civilisation of Asia. The wise men of the East have been puzzling, and are puzzling, as to what may be the regulative secret of life which can be passed from West to East without the wanton destruction of their own inheritance which they so rightly prize. More and more it is becoming evident that what the West can most readily give to the East is its science and its scientific outlook. This is transferable from country to country, and from race to race, wherever there is a rational society.

Another feature that sets science apart from other European movements of the sixteenth and seventeenth centuries is its universality. Modern science was born in Europe, but its home is the whole world. Over the last two centuries, Western ways have had a long and confusing impact on Asian civilization. Wise people in the East have struggled, and still struggle, to understand what guiding principle of life the West could pass to the East. They seek a principle that would not needlessly destroy their own heritage, which they rightly value so highly. More and more, it is becoming clear that science and the scientific outlook are what the West can most readily give to the East. Science and the scientific outlook can be passed from country to country and from race to race, wherever there is a rational society.

In this course of lectures I shall not discuss the details of scientific discovery. My theme is the energising of a state of mind in the modern world, its broad generalisations, and its impact upon other spiritual forces. There are two ways of reading history, forwards and backwards. In the history of thought, we require both methods. A climate of opinion—to use the happy phrase of a seventeenth century writer—requires for its understanding the consideration of its antecedents and its issues. Accordingly in this lecture I shall consider some of the antecedents of our modern approach to the investigation of nature.

In this series of lectures, I will not discuss the details of scientific discovery. My theme is the growing energy of a modern way of thinking, its broad generalizations, and its impact on other spiritual forces. There are two ways to read history: forwards and backwards. In the history of thought, we need both methods. To understand a climate of opinion, we must consider both what came before it and what followed from it. The phrase “climate of opinion” comes from a seventeenth-century writer. In this lecture, then, I will consider some of the earlier influences on our modern approach to investigating nature.

In the first place, there can be no living science unless there is a widespread instinctive conviction in the existence of an Order of Things, and, in particular, of an Order of Nature. I have used the word instinctive advisedly. It does not matter what men say in words, so long as their activities are controlled by settled instincts. The words may ultimately destroy the instincts. But until this has occurred, words do not count. This remark is important in respect to the history of scientific thought. For we shall find that since the time of Hume, the fashionable scientific philosophy has been such as to deny the rationality of science. This conclusion lies upon the surface of Hume’s philosophy. Take, for example, the following passage from Section IV of his Inquiry Concerning Human Understanding:

First, science cannot thrive unless people widely and instinctively believe in an Order of Things, especially an Order of Nature. I have chosen the word instinctively deliberately. What people say does not matter, as long as settled instincts govern their actions. Words may eventually destroy those instincts. But until that happens, words do not count. This point is important to the history of scientific thought. Since Hume’s time, the fashionable philosophy of science has denied that science is rational. This conclusion is evident in Hume’s philosophy. Take, for example, the following passage from Section IV of his Inquiry Concerning Human Understanding:

If the cause in itself discloses no information as to the effect, so that the first invention of it must be entirely arbitrary, it follows at once that science is impossible, except in the sense of establishing entirely arbitrary connections which are not warranted by anything intrinsic to the natures either of causes or effects. Some variant of Hume’s philosophy has generally prevailed among men of science. But scientific faith has risen to the occasion, and has tacitly removed the philosophic mountain.

If a cause itself reveals nothing about its effect, then the first idea of that effect must be entirely arbitrary. It follows at once that science is impossible, except as a way of establishing entirely arbitrary connections. Nothing in the nature of either causes or effects justifies these connections. Some version of Hume’s philosophy has generally prevailed among scientists. But scientific faith has risen to the occasion and quietly removed the philosophical mountain.

In view of this strange contradiction in scientific thought, it is of the first importance to consider the antecedents of a faith which is impervious to the demand for a consistent rationality. We have therefore to trace the rise of the instinctive faith that there is an Order of Nature which can be traced in every detailed occurrence.

This strange contradiction in scientific thought makes it essential to consider the origins of a faith that resists demands for logical consistency. We must therefore trace the rise of the instinctive faith that there is an Order of Nature. This order can be found in every event, down to its smallest details.

Of course we all share in this faith, and we therefore believe that the reason for the faith is our apprehension of its truth. But the formation of a general idea—such as the idea of the Order of Nature—, and the grasp of its importance, and the observation of its exemplification in a variety of occasions are by no means the necessary consequences of the truth of the idea in question. Familiar things happen, and mankind does not bother about them. It requires a very unusual mind to undertake the analysis of the obvious. Accordingly I wish to consider the stages in which this analysis became explicit, and finally became unalterably impressed upon the educated minds of Western Europe.

Of course, we all share this faith, so we believe it rests on our recognition of its truth. But the truth of an idea does not necessarily lead us to form it as a general idea. Nor does it necessarily lead us to grasp its importance or notice examples of it in various situations. The idea of the Order of Nature is one such idea. Familiar things happen, and people do not pay attention to them. It takes a very unusual mind to analyze what seems obvious. So I want to consider the stages through which this analysis became explicit. I also want to consider how it finally became permanently fixed in the minds of educated people in Western Europe.

Obviously, the main recurrences of life are too insistent to escape the notice of the least rational of humans; and even before the dawn of rationality, they have impressed themselves upon the instincts of animals. It is unnecessary to labour the point, that in broad outline certain general states of nature recur, and that our very natures have adapted themselves to such repetitions.

Clearly, the recurring patterns of life are too persistent to escape even the least rational human's notice. Even before rational thought emerged, these patterns shaped the instincts of animals. There is no need to dwell on the point. Certain general conditions in nature recur in broad outline, and our very natures have adapted to these repetitions.

But there is a complementary fact which is equally true and equally obvious:—nothing ever really recurs in exact detail. No two days are identical, no two winters. What has gone, has gone forever. Accordingly the practical philosophy of mankind has been to expect the broad recurrences, and to accept the details as emanating from the inscrutable womb of things, beyond the ken of rationality. Men expected the sun to rise, but the wind bloweth where it listeth.

But there is a complementary fact that is equally true and equally obvious: nothing ever repeats in exact detail. No two days are identical, and no two winters are identical. What has gone is gone forever. So people have generally expected broad patterns to repeat. They have accepted the details as coming from the mysterious womb of things, beyond the reach of reason. People expected the sun to rise, but the wind blows where it pleases.

Certainly from the classical Greek civilisation onwards there have been men, and indeed groups of men, who have placed themselves beyond this acceptance of an ultimate irrationality. Such men have endeavoured to explain all phenomena as the outcome of an order of things which extends to every detail. Geniuses such as Aristotle, or Archimedes, or Roger Bacon, must have been endowed with the full scientific mentality, which instinctively holds that all things great and small are conceivable as exemplifications of general principles which reign throughout the natural order.

Certainly, since classical Greek civilization, some men and groups of men have rejected the idea of an ultimate irrationality. They have tried to explain all phenomena as the result of an order that extends to every detail. Geniuses such as Aristotle, Archimedes, and Roger Bacon must have possessed the full scientific mindset. This mindset instinctively holds that all things, great and small, can be understood as examples of general principles governing the natural order.

But until the close of the Middle Ages the general educated public did not feel that intimate conviction, and that detailed interest, in such an idea, so as to lead to an unceasing supply of men, with ability and opportunity adequate to maintain a coordinated search for the discovery of these hypothetical principles. Either people were doubtful about the existence of such principles, or were doubtful about any success in finding them, or took no interest in thinking about them, or were oblivious to their practical importance when found. For whatever reason, search was languid, if we have regard to the opportunities of a high civilisation and the length of time concerned. Why did the pace suddenly quicken in the sixteenth and seventeenth centuries? At the close of the Middle Ages a new mentality discloses itself. Invention stimulated thought, thought quickened physical speculation, Greek manuscripts disclosed what the ancients had discovered. Finally although in the year 1500 Europe knew less than Archimedes who died in the year 212 B. C., yet in the year 1700, Newton’s Principia had been written and the world was well started on the modern epoch.

But until the end of the Middle Ages, educated people generally lacked a firm conviction in this idea. They also lacked enough detailed interest in it. As a result, there was no steady supply of people with the ability and opportunity to sustain a coordinated search for these hypothetical principles. Some people doubted that such principles existed. Others doubted that they could be found, had no interest in thinking about them, or overlooked their practical importance if discovered. Whatever the reason, the search was slow, considering the opportunities offered by a highly developed civilization and the length of time involved. Why did the pace suddenly quicken in the sixteenth and seventeenth centuries? At the end of the Middle Ages, a new way of thinking appeared. Invention stimulated thought, thought encouraged speculation about the physical world, and Greek manuscripts revealed what the ancients had discovered. Finally, although Europe knew less in 1500 than Archimedes, who died in 212 B. C., by 1700 Newton’s Principia had been written. The world was well on its way into the modern age.

There have been great civilisations in which the peculiar balance of mind required for science has only fitfully appeared and has produced the feeblest result. For example, the more we know of Chinese art, of Chinese literature, and of the Chinese philosophy of life, the more we admire the heights to which that civilization attained. For thousands of years, there have been in China acute and learned men patiently devoting their lives to study. Having regard to the span of time, and to the population concerned, China forms the largest volume of civilisation which the world has seen. There is no reason to doubt the intrinsic capacity of individual Chinamen for the pursuit of science. And yet Chinese science is practically negligible. There is no reason to believe that China if left to itself would have ever produced any progress in science. The same may be said of India. Furthermore, if the Persians had enslaved the Greeks, there is no definite ground for belief that science would have flourished in Europe. The Romans showed no particular originality in that line. Even as it was, the Greeks, though they founded the movement, did not sustain it with the concentrated interest which modern Europe has shown. I am not alluding to the last few generations of the European peoples on both sides of the ocean; I mean the smaller Europe of the Reformation period, distracted as it was with wars and religious disputes. Consider the world of the eastern Mediterranean, from Sicily to western Asia, during the period of about 1400 years from the death of Archimedes [in 212 B. C.] to the irruption of the Tartars. There were wars and revolutions and large changes of religion: but nothing much worse than the wars of the sixteenth and seventeenth centuries throughout Europe. There was a great and wealthy civilisation, Pagan, Christian, Mahometan. In that period a great deal was added to science. But on the whole the progress was slow and wavering; and, except in mathematics, the men of the Renaissance practically started from the position which Archimedes had reached. There had been some progress in medicine and some progress in astronomy. But the total advance was very little compared to the marvellous success of the seventeenth century. For example, compare the progress of scientific knowledge from the year 1560, just before the births of Galileo and of Kepler, up to the year 1700, when Newton was in the height of his fame, with the progress in the ancient period, already mentioned, exactly ten times as long.

There have been great civilizations where the particular balance of mind needed for science appeared only occasionally. In those civilizations, it produced very little. For example, the more we learn about Chinese art, literature, and philosophy of life, the more we admire what that civilization achieved. For thousands of years, China has had sharp and learned people who patiently devoted their lives to study. Given its long history and large population, China represents the largest civilization the world has seen. There is no reason to doubt the natural ability of individual Chinese people to pursue science. Yet Chinese science is practically negligible. There is no reason to believe that China, left to itself, would ever have made progress in science. The same may be said of India. Moreover, if the Persians had enslaved the Greeks, there is no definite reason to believe science would have flourished in Europe. The Romans showed no particular originality in science. Even as things were, the Greeks founded the scientific movement but did not sustain it with the concentrated interest that modern Europe has shown. I do not mean the European peoples on both sides of the ocean in the last few generations. I mean the smaller Europe of the Reformation period, despite its wars and religious disputes. Consider the eastern Mediterranean world, from Sicily to western Asia. Consider the roughly 1,400 years from the death of Archimedes [in 212 B. C.] to the invasion of the Tartars. There were wars, revolutions, and major religious changes. But these were not much worse than the wars throughout Europe in the sixteenth and seventeenth centuries. There was a great and wealthy civilization, Pagan, Christian, and Muslim. During that period, a great deal was added to science. But overall, progress was slow and uneven. Except in mathematics, the people of the Renaissance practically started from where Archimedes had left off. There had been some progress in medicine and some in astronomy. But the total advance was very small compared with the marvelous success of the seventeenth century. For example, compare two periods of progress in scientific knowledge. One runs from 1560, just before the births of Galileo and Kepler, to 1700, when Newton was at the height of his fame. The other is the ancient period already mentioned, exactly ten times as long.

Nevertheless, Greece was the mother of Europe; and it is to Greece that we must look in order to find the origin of our modern ideas. We all know that on the eastern shores of the Mediterranean there was a very flourishing school of Ionian philosophers, deeply interested in theories concerning nature. Their ideas have been transmitted to us, enriched by the genius of Plato and Aristotle. But, with the exception of Aristotle, and it is a large exception, this school of thought had not attained to the complete scientific mentality. In some ways, it was better. The Greek genius was philosophical, lucid and logical. The men of this group were primarily asking philosophical questions. What is the substratum of nature? Is it fire, or earth, or water, or some combination of any two, or of all three? Or is it a mere flux, not reducible to some static material? Mathematics interested them mightily. They invented its generality, analysed its premises, and made notable discoveries of theorems by a rigid adherence to deductive reasoning. Their minds were infected with an eager generality. They demanded clear, bold ideas, and strict reasoning from them. All this was excellent; it was genius; it was ideal preparatory work. But it was not science as we understand it. The patience of minute observation was not nearly so prominent. Their genius was not so apt for the state of imaginative muddled suspense which precedes successful inductive generalisation. They were lucid thinkers and bold reasoners.

Nevertheless, Greece was the mother of Europe. We must look to Greece to find the origin of our modern ideas. We all know that a thriving school of Ionian philosophers existed on the eastern shores of the Mediterranean. These philosophers were deeply interested in theories about nature. Their ideas have reached us, enriched by the genius of Plato and Aristotle. But this school of thought had not developed a fully scientific mentality, with the important exception of Aristotle. In some ways, the school was better. Greek genius was philosophical, clear, and logical. These thinkers were primarily asking philosophical questions. What underlies nature? Is it fire, earth, water, or a combination of any two or all three? Or is nature merely a constant flow that cannot be reduced to any fixed material? Mathematics interested them enormously. They developed its general principles, examined its premises, and made notable discoveries of theorems through strict deductive reasoning. Their minds were filled with an eagerness for general ideas. They demanded clear, bold ideas and strict reasoning from those ideas. All this was excellent. It was genius, and it was ideal preparatory work. But it was not science as we understand it. Patient, detailed observation was much less prominent. Their genius was less suited to the state of imaginative uncertainty and confusion that comes before successful inductive generalization. They were clear thinkers and bold reasoners.

Of course there were exceptions, and at the very top: for example, Aristotle and Archimedes. Also for patient observation, there were the astronomers. There was a mathematical lucidity about the stars, and a fascination about the small numerable band of run-a-way planets.

Of course, there were exceptions among the very greatest, such as Aristotle and Archimedes. There were also astronomers, who observed patiently. The stars had a clear mathematical order, and the small, countable group of wandering planets held a fascination.

Every philosophy is tinged with the colouring of some secret imaginative background, which never emerges explicitly into its trains of reasoning. The Greek view of nature, at least that cosmology transmitted from them to later ages, was essentially dramatic. It is not necessarily wrong for this reason: but it was overwhelmingly dramatic. It thus conceived nature as articulated in the way of a work of dramatic art, for the exemplification of general ideas converging to an end. Nature was differentiated so as to provide its proper end for each thing. There was the centre of the universe as the end of motion for those things which are heavy, and the celestial spheres as the end of motion for those things whose natures lead them upwards. The celestial spheres were for things which are impassible and ingenerable, the lower regions for things impassible and generable. Nature was a drama in which each thing played its part.

Every philosophy is colored by some hidden imaginative background that never appears explicitly in its reasoning. The Greek view of nature, at least the cosmology passed down from them to later ages, was essentially dramatic. That does not necessarily make it wrong, but it was overwhelmingly dramatic. It pictured nature as structured like a dramatic work of art, illustrating general ideas that come together toward an end. Nature was arranged so that each thing had its proper end. The center of the universe was the destination of heavy things. The celestial spheres were the destination of things whose natures led them upward. The celestial spheres were for things that could not be affected or generated. The lower regions were for things that could not be affected but could be generated. Nature was a drama in which each thing played its part.

I do not say that this is a view to which Aristotle would have subscribed without severe reservations, in fact without the sort of reservations which we ourselves would make. But it was the view which subsequent Greek thought extracted from Aristotle and passed on to the Middle Ages. The effect of such an imaginative setting for nature was to damp down the historical spirit. For it was the end which seemed illuminating, so why bother about the beginning? The Reformation and the scientific movement were two aspects of the historical revolt which was the dominant intellectual movement of the later Renaissance. The appeal to the origins of Christianity, and Francis Bacon’s appeal to efficient causes as against final causes, were two sides of one movement of thought. Also for this reason Galileo and his adversaries were at hopeless cross purposes, as can be seen from his Dialogues on the Two Systems of the World.

I do not claim that Aristotle would have accepted this view without serious reservations. In fact, he would have had the same kind of reservations we ourselves would have. But this was the view that later Greek thinkers drew from Aristotle and passed on to the Middle Ages. This imaginative view of nature weakened interest in history. The end seemed to explain everything, so why bother about the beginning? The Reformation and the scientific movement were two aspects of the historical revolt. This revolt was the dominant intellectual movement of the later Renaissance. The appeal to the origins of Christianity and Francis Bacon’s appeal to efficient causes rather than final causes were two sides of the same movement of thought. For this reason, too, Galileo and his opponents were hopelessly at cross purposes. This can be seen in his Dialogues on the Two Systems of the World.

Galileo keeps harping on how things happen, whereas his adversaries had a complete theory as to why things happen. Unfortunately the two theories did not bring out the same results. Galileo insists upon ‘irreducible and stubborn facts,’ and Simplicius, his opponent, brings forward reasons, completely satisfactory, at least to himself. It is a great mistake to conceive this historical revolt as an appeal to reason. On the contrary, it was through and through an anti-intellectualist movement. It was the return to the contemplation of brute fact; and it was based on a recoil from the inflexible rationality of medieval thought. In making this statement I am merely summarising what at the time the adherents of the old régime themselves asserted. For example, in the fourth book of Father Paul Sarpi’s History of the Council of Trent, you will find that in the year 1551 the Papal Legates who presided over the Council ordered: ‘That the Divines ought to confirm their opinions with the holy Scripture, Traditions of the Apostles, sacred and approved Councils, and by the Constitutions and Authorities of the holy Fathers; that they ought to use brevity, and avoid superfluous and unprofitable questions, and perverse contentions.... This order did not please the Italian Divines; who said it was a novity, and a condemning of School-Divinity, which, in all difficulties, useth reason, and because it was not lawful [i.e., by this decree] to treat as St. Thomas [Aquinas], St. Bonaventure, and other famous men did.’

Galileo keeps returning to the question of how things happen. His opponents, on the other hand, had a complete theory of why things happen. Unfortunately, the two theories did not produce the same results. Galileo insists on ‘irreducible and stubborn facts,’ while his opponent Simplicius offers reasons that are completely satisfactory, at least to himself. It is a great mistake to think of this historical revolt as an appeal to reason. On the contrary, it was an anti-intellectualist movement through and through. It was a return to looking at brute facts, driven by a recoil from the rigid rationality of medieval thought. In saying this, I am only summarizing what supporters of the old regime themselves said at the time. For example, Father Paul Sarpi’s History of the Council of Trent describes an order from 1551. In the fourth book, Sarpi says that the Papal Legates who presided over the Council ordered: ‘The theologians should support their opinions with holy Scripture, the Traditions of the Apostles, sacred and approved Councils, and the Constitutions and Authorities of the holy Fathers. They should be brief and avoid unnecessary and unprofitable questions and perverse disputes.... This order did not please the Italian theologians. They said it was an innovation and a condemnation of Scholastic theology, which uses reason in all difficulties. They also objected because it was not permitted [i.e., by this decree] to treat questions as St. Thomas [Aquinas], St. Bonaventure, and other famous men did.’

It is impossible not to feel sympathy with these Italian divines, maintaining the lost cause of unbridled rationalism. They were deserted on all hands. The Protestants were in full revolt against them. The Papacy failed to support them, and the Bishops of the Council could not even understand them. For a few sentences below the foregoing quotation, we read: ‘Though many complained here-of [i.e., of the Decree], yet it prevailed but little, because generally the Fathers [i.e., the Bishops] desired to hear men speak with intelligible terms, not abstrusely, as in the matter of Justification, and others already handled.’

It is impossible not to sympathize with these Italian theologians, who defended the lost cause of unrestrained rationalism. They were abandoned by everyone. The Protestants were in full revolt against them. The Papacy did not support them, and the Bishops of the Council could not even understand them. A few sentences after the passage quoted above, we read: ‘Though many complained about it [i.e., the Decree], their complaints had little effect. That was because the Fathers [i.e., the Bishops] generally wanted to hear people speak clearly. They did not want obscure language like that used in discussing Justification and other matters already dealt with.’

Poor belated medievalists! When they used reason they were not even intelligible to the ruling powers of their epoch. It will take centuries before stubborn facts are reducible by reason, and meanwhile the pendulum swings slowly and heavily to the extreme of the historical method.

Poor medieval thinkers, so out of step with their times! When they used reason, the ruling powers of their age could not even understand them. It will take centuries for reason to make sense of stubborn facts. Meanwhile, the pendulum swings slowly and heavily toward the opposite extreme, the historical method.

Forty-three years after the Italian divines had written this memorial, Richard Hooker in his famous Laws of Ecclesiastical Polity makes exactly the same complaint of his Puritan adversaries.¹ Hooker’s balanced thought—from which the appellation ‘The Judicious Hooker’ is derived—, and his diffuse style, which is the vehicle of such thought, make his writings singularly unfit for the process of summarising by a short, pointed quotation. But, in the section referred to, he reproaches his opponents with Their Disparagement of Reason; and in support of his own position definitely refers to ‘The greatest amongst the school-divines,’ by which designation I presume that he refers to St. Thomas Aquinas.

Forty-three years after the Italian theologians wrote this memorial, Richard Hooker made exactly the same complaint about his Puritan opponents in his famous Laws of Ecclesiastical Polity.¹ Hooker’s balanced thinking earned him the name ‘The Judicious Hooker’. His style was wordy, as suited that kind of thinking. Together, these qualities make his writings especially difficult to sum up in a short, pointed quotation. But in the section mentioned, he criticizes his opponents for Their Disparagement of Reason. To support his own position, he specifically refers to ‘The greatest amongst the school-divines’. I assume that he means St. Thomas Aquinas.

Hooker’s Ecclesiastical Polity was published just before Sarpi’s Council of Trent. Accordingly there was complete independence between the two works. But both the Italian divines of 1551, and Hooker at the end of that century testify to the anti-rationalist trend of thought at that epoch, and in this respect contrast their own age with the epoch of scholasticism.

Hooker’s Ecclesiastical Polity was published just before Sarpi’s Council of Trent. The two works were therefore completely independent of each other. But both the Italian theologians of 1551 and Hooker at the end of that century testify to their age’s anti-rationalist trend. In this respect, they contrast their own age with the age of scholasticism.

This reaction was undoubtedly a very necessary corrective to the unguarded rationalism of the Middle Ages. But reactions run to extremes. Accordingly, although one outcome of this reaction was the birth of modern science, yet we must remember that science thereby inherited the bias of thought to which it owes its origin.

This reaction was undoubtedly a necessary corrective to the uncritical rationalism of the Middle Ages. But reactions can go to extremes. Although modern science was born from this reaction, we must remember that it inherited the bias of thought that gave rise to it.

The effect of Greek dramatic literature was many-sided so far as concerns the various ways in which it indirectly affected medieval thought. The pilgrim fathers of the scientific imagination as it exists today, are the great tragedians of ancient Athens, Aeschylus, Sophocles, Euripides. Their vision of fate, remorseless and indifferent, urging a tragic incident to its inevitable issue, is the vision possessed by science. Fate in Greek Tragedy becomes the order of nature in modern thought. The absorbing interest in the particular heroic incidents, as an example and a verification of the workings of fate, reappears in our epoch as concentration of interest on the crucial experiments. It was my good fortune to be present at the meeting of the Royal Society in London when the Astronomer Royal for England announced that the photographic plates of the famous eclipse, as measured by his colleagues in Greenwich Observatory, had verified the prediction of Einstein that rays of light are bent as they pass in the neighbourhood of the sun. The whole atmosphere of tense interest was exactly that of the Greek drama: we were the chorus commenting on the decree of destiny as disclosed in the development of a supreme incident. There was dramatic quality in the very staging:—the traditional ceremonial, and in the background the picture of Newton to remind us that the greatest of scientific generalisations was now, after more than two centuries, to receive its first modification. Nor was the personal interest wanting: a great adventure in thought had at length come safe to shore.

Greek dramatic literature indirectly influenced medieval thought in many ways. The founders of the scientific imagination as we know it today were the great tragedians of ancient Athens: Aeschylus, Sophocles, Euripides. Science shares their vision of fate, relentless and indifferent, driving a tragic event toward its inevitable outcome. Fate in Greek tragedy becomes the order of nature in modern thought. Greek dramatists focused their intense interest on particular heroic events as examples and evidence of fate at work. In our own time, that interest reappears in our focus on crucial experiments. I was fortunate to attend a meeting of the Royal Society in London when the Astronomer Royal for England made an announcement. His colleagues at Greenwich Observatory had measured the photographic plates of the famous eclipse. Their measurements had confirmed Einstein's prediction that rays of light bend as they pass near the sun. The atmosphere of tense interest was exactly like that of Greek drama. We were the chorus, commenting on the decree of destiny as a momentous event revealed it. Even the staging had dramatic quality. There was the traditional ceremony and, in the background, the picture of Newton. The picture reminded us that the greatest of scientific generalizations was now, after more than two centuries, to undergo its first revision. Nor was personal interest absent: a great adventure in thought had at last reached safe harbor.

Let me here remind you that the essence of dramatic tragedy is not unhappiness. It resides in the solemnity of the remorseless working of things. This inevitableness of destiny can only be illustrated in terms of human life by incidents which in fact involve unhappiness. For it is only by them that the futility of escape can be made evident in the drama. This remorseless inevitableness is what pervades scientific thought. The laws of physics are the decrees of fate.

Let me remind you that the essence of dramatic tragedy is not unhappiness. It lies in the solemn, relentless working of events. In human life, the inevitability of fate can only be illustrated through events that involve unhappiness. Only such events can show, in a drama, that escape is futile. This relentless inevitability runs through scientific thought. The laws of physics are the decrees of fate.

The conception of the moral order in the Greek plays was certainly not a discovery of the dramatists. It must have passed into the literary tradition from the general serious opinion of the times. But in finding this magnificent expression, it thereby deepened the stream of thought from which it arose. The spectacle of a moral order was impressed upon the imagination of classical civilisation.

The idea of a moral order in Greek plays was certainly not the dramatists' discovery. It must have entered the literary tradition from the serious views generally held at the time. But by finding such magnificent expression, the idea deepened the current of thought from which it arose. The vision of a moral order left a lasting impression on the imagination of classical civilization.

The time came when that great society decayed, and Europe passed into the Middle Ages. The direct influence of Greek literature vanished. But the concept of the moral order and of the order of nature had enshrined itself in the Stoic philosophy. For example, Lecky in his History of European Morals tells us ‘Seneca maintains that the Divinity has determined all things by an inexorable law of destiny, which He has decreed, but which He Himself obeys.’ But the most effective way in which the Stoics influenced the mentality of the Middle Ages was by the diffused sense of order which arose from Roman law. Again to quote Lecky, ‘The Roman legislation was in a two-fold manner the child of philosophy. It was in the first place formed upon the philosophical model, for, instead of being a mere empirical system adjusted to the existing requirements of society, it laid down abstract principles of right to which it endeavoured to conform; and, in the next place, these principles were borrowed directly from Stoicism.’ In spite of the actual anarchy throughout large regions in Europe after the collapse of the Empire, the sense of legal order always haunted the racial memories of the Imperial populations. Also the Western Church was always there as a living embodiment of the traditions of Imperial rule.

Eventually, that great society declined, and Europe entered the Middle Ages. Greek literature no longer had a direct influence. But the ideas of moral order and the order of nature had become central to Stoic philosophy. For example, Lecky tells us in his History of European Morals: ‘Seneca maintains that God has determined all things by a law of destiny that cannot be changed. God has decreed this law, but he himself obeys it.’ The Stoics most effectively shaped medieval thinking through the widespread sense of order that came from Roman law. Again, to quote Lecky: ‘Roman law was the child of philosophy in two ways. First, it was shaped on a philosophical model. It was not merely a practical system adjusted to society’s existing needs. Instead, it set out abstract principles of right and tried to follow them. Second, these principles were borrowed directly from Stoicism.’ After the Empire collapsed, much of Europe fell into anarchy. Despite this, a sense of legal order always lingered in the inherited memories of the Empire’s peoples. The Western Church was also always there, a living embodiment of the traditions of Imperial rule.

It is important to notice that this legal impress upon medieval civilisation was not in the form of a few wise precepts which should permeate conduct. It was the conception of a definite articulated system which defines the legality of the detailed structure of social organism, and of the detailed way in which it should function. There was nothing vague. It was not a question of admirable maxims, but of definite procedure to put things right and to keep them there. The Middle Ages formed one long training of the intellect of Western Europe in the sense of order. There may have been some deficiency in respect to practice. But the idea never for a moment lost its grip. It was preëminently an epoch of orderly thought, rationalist through and through. The very anarchy quickened the sense for coherent system; just as the modern anarchy of Europe has stimulated the intellectual vision of a League of Nations.

It is important to notice that law influenced medieval civilization in more than a few wise rules meant to guide conduct. Instead, law offered a definite, organized system. This system defined what was lawful in the detailed structure of society and in how society should function. There was nothing vague about it. The issue was not admirable maxims, but definite procedures for putting things right and keeping them that way. Throughout the Middle Ages, the minds of Western Europeans were trained to recognize order. Practice may have fallen somewhat short. But the idea of order never lost its hold for a moment. Above all, the Middle Ages were an era of orderly thought, rationalist through and through. The very anarchy of the time sharpened the desire for a coherent system, just as modern Europe's anarchy has inspired the intellectual vision of a League of Nations.

But for science something more is wanted than a general sense of the order in things. It needs but a sentence to point out how the habit of definite exact thought was implanted in the European mind by the long dominance of scholastic logic and scholastic divinity. The habit remained after the philosophy had been repudiated, the priceless habit of looking for an exact point and of sticking to it when found. Galileo owes more to Aristotle than appears on the surface of his Dialogues: he owes to him his clear head and his analytic mind.

But science needs more than a general sense that things have an order. Scholastic logic and theology dominated European thought for a long time, instilling a habit of clear, precise thinking. The philosophy was later rejected, but the habit remained. It was the priceless habit of looking for a precise point and sticking to it once found. Galileo owes more to Aristotle than is apparent in his Dialogues. He owes Aristotle his clear head and analytical mind.

I do not think, however, that I have even yet brought out the greatest contribution of medievalism to the formation of the scientific movement. I mean the inexpugnable belief that every detailed occurrence can be correlated with its antecedents in a perfectly definite manner, exemplifying general principles. Without this belief the incredible labours of scientists would be without hope. It is this instinctive conviction, vividly poised before the imagination, which is the motive power of research:—that there is a secret, a secret which can be unveiled. How has this conviction been so vividly implanted on the European mind?

However, I do not think I have yet explained medievalism’s greatest contribution to the development of science. I mean the unshakable belief that every event can be linked to what came before it in a perfectly definite way, showing general principles at work. Without this belief, scientists’ extraordinary labors would have no hope of success. The driving force of research is an instinctive conviction, vivid in the imagination, that there is a secret that can be uncovered. How did this conviction become so deeply rooted in the European mind?

When we compare this tone of thought in Europe with the attitude of other civilisations when left to themselves, there seems but one source for its origin. It must come from the medieval insistence on the rationality of God, conceived as with the personal energy of Jehovah and with the rationality of a Greek philosopher. Every detail was supervised and ordered: the search into nature could only result in the vindication of the faith in rationality. Remember that I am not talking of the explicit beliefs of a few individuals. What I mean is the impress on the European mind arising from the unquestioned faith of centuries. By this I mean the instinctive tone of thought and not a mere creed of words.

When we compare this way of thinking in Europe with the outlook of other civilizations left to themselves, it seems to have only one source. It must come from the medieval belief that God is rational. God was understood to have the personal energy of Jehovah and the rationality of a Greek philosopher. Every detail was supervised and ordered. So investigating nature could only confirm faith in rationality. Remember that I am not talking about the explicit beliefs of a few individuals. I mean the effect on the European mind of centuries of unquestioned faith. I mean an instinctive way of thinking, not just a creed expressed in words.

In Asia, the conceptions of God were of a being who was either too arbitrary or too impersonal for such ideas to have much effect on instinctive habits of mind. Any definite occurrence might be due to the fiat of an irrational despot, or might issue from some impersonal, inscrutable origin of things. There was not the same confidence as in the intelligible rationality of a personal being. I am not arguing that the European trust in the scrutability of nature was logically justified even by its own theology. My only point is to understand how it arose. My explanation is that the faith in the possibility of science, generated antecedently to the development of modern scientific theory, is an unconscious derivative from medieval theology.

In Asia, people imagined God as a being who was either too arbitrary or too impersonal. As a result, such ideas had little effect on their instinctive habits of mind. Any particular event might result from the command of an irrational despot. Or it might come from some impersonal, mysterious source of all things. There was less confidence in the understandable rationality of a personal being. I am not arguing that European theology logically justified Europeans’ trust that nature could be understood. My only aim is to understand how that trust arose. My explanation is that faith in the possibility of science came unconsciously from medieval theology. This faith arose before modern scientific theory developed.

But science is not merely the outcome of instinctive faith. It also requires an active interest in the simple occurrences of life for their own sake.

But science is not just the result of instinctive faith. It also requires an active interest in everyday events for their own sake.

This qualification ‘for their own sake’ is important. The first phase of the Middle Ages was an age of symbolism. It was an age of vast ideas, and of primitive technique. There was little to be done with nature, except to coin a hard living from it. But there were realms of thought to be explored, realms of philosophy and realms of theology. Primitive art could symbolise those ideas which filled all thoughtful minds. The first phase of medieval art has a haunting charm beyond compare: its own intrinsic quality is enhanced by the fact that its message, which stretched beyond art’s own self-justification of aesthetic achievement, was the symbolism of things lying behind nature itself. In this symbolic phase, medieval art energised in nature as its medium, but pointed to another world.

The phrase ‘for their own sake’ is important. The first phase of the Middle Ages was an age of symbolism. It was an age of vast ideas and primitive techniques. People could do little with nature except make a hard living from it. But there were realms of thought to explore, in philosophy and theology. Primitive art could symbolize the ideas that filled all thoughtful minds. Art from the first phase of the Middle Ages has a haunting charm beyond compare. Its own beauty is enhanced by its message, which went beyond art’s own justification as an aesthetic achievement. That message symbolized things lying behind nature itself. In this symbolic phase, medieval art worked through nature as its medium, but pointed to another world.

In order to understand the contrast between these early Middle Ages and the atmosphere required by the scientific mentality, we should compare the sixth century in Italy with the sixteenth century. In both centuries the Italian genius was laying the foundations of a new epoch. The history of the three centuries preceding the earlier period, despite the promise for the future introduced by the rise of Christianity, is overwhelmingly infected by the sense of the decline of civilisation. In each generation something has been lost. As we read the records, we are haunted by the shadow of the coming barbarism. There are great men, with fine achievements in action or in thought. But their total effect is merely for some short time to arrest the general decline. In the sixth century we are, so far as Italy is concerned, at the lowest point of the curve. But in that century every action is laying the foundation for the tremendous rise of the new European civilisation. In the background the Byzantine Empire, under Justinian, in three ways determined the character of the early Middle Ages in Western Europe. In the first place, its armies, under Belisarius and Narses, cleared Italy from the Gothic domination. In this way, the stage was freed for the exercise of the old Italian genius for creating organisations which shall be protective of ideals of cultural activity. It is impossible not to sympathise with the Goths: yet there can be no doubt but that a thousand years of the Papacy were infinitely more valuable for Europe than any effects derivable from a well-established Gothic kingdom of Italy.

To understand how these early Middle Ages differed from the atmosphere needed for scientific thinking, we should compare sixth-century Italy with sixteenth-century Italy. In both centuries, Italian genius was laying the foundations of a new era. Christianity had risen during the three centuries before the earlier period, bringing promise for the future. Yet the history of those centuries is overwhelmingly marked by a sense of civilizational decline. Each generation lost something. As we read the records, the shadow of the coming barbarism haunts us. There were great men who achieved fine things in action or thought. But together, they did no more than briefly halt the general decline. In the sixth century, Italy had reached the lowest point of the curve. Yet every action in that century was laying the foundation for the tremendous rise of the new European civilization. In the background, the Byzantine Empire under Justinian shaped the character of the early Middle Ages in Western Europe in three ways. First, its armies, led by Belisarius and Narses, freed Italy from Gothic rule. This cleared the way for the old Italian genius for creating institutions to protect ideals of cultural activity. It is impossible not to sympathize with the Goths. Yet there can be no doubt that a thousand years of the Papacy were infinitely more valuable for Europe than any effects a firmly established Gothic kingdom in Italy could have produced.

In the second place, the codification of the Roman law established the ideal of legality which dominated the sociological thought of Europe in the succeeding centuries. Law is both an engine for government, and a condition restraining government. The canon law of the Church, and the civil law of the State, owe to Justinian’s lawyers their influence on the development of Europe. They established in the Western mind the ideal that an authority should be at once lawful, and law-enforcing, and should in itself exhibit a rationally adjusted system of organisation. The sixth century in Italy gave the initial exhibition of the way in which the impress of these ideas was fostered by contact with the Byzantine Empire.

Second, the codification of Roman law established an ideal of legality. This ideal dominated European thinking about society in the centuries that followed. Law is both a tool for government and a constraint on it. The Church’s canon law and the State’s civil law owe their influence on Europe’s development to Justinian’s lawyers. Those lawyers established an ideal in the Western mind: an authority should be lawful, enforce the law, and have a rationally ordered structure. Sixth-century Italy provided the first example of how contact with the Byzantine Empire helped these ideas take root.

Thirdly, in the non-political spheres of art and learning Constantinople exhibited a standard of realised achievement which, partly by the impulse to direct imitation, and partly by the indirect inspiration arising from the mere knowledge that such things existed, acted as a perpetual spur to Western culture. The wisdom of the Byzantines, as it stood in the imagination of the first phase of medieval mentality, and the wisdom of the Egyptians as it stood in the imagination of the early Greeks, played analogous rôles. Probably the actual knowledge of these respective wisdoms was, in either case, about as much as was good for the recipients. They knew enough to know the sort of standards which are attainable, and not enough to be fettered by static and traditional ways of thought. Accordingly, in both cases men went ahead on their own and did better. No account of the rise of the European scientific mentality can omit some notice of this influence of the Byzantine civilisation in the background. In the sixth century there is a crisis in the history of the relations between the Byzantines and the West; and this crisis is to be contrasted with the influence of Greek literature on European thought in the fifteenth and sixteenth centuries. The two outstanding men, who in the Italy of the sixth century laid the foundations of the future, were St. Benedict and Gregory the Great. By reference to them, we can at once see how absolutely in ruins was the approach to the scientific mentality which had been attained by the Greeks. We are at the zero point of scientific temperature. But the life-work of Gregory and of Benedict contributed elements to the reconstruction of Europe which secured that this reconstruction, when it arrived, should include a more effective scientific mentality than that of the ancient world. The Greeks were over-theoretical. For them science was an offshoot of philosophy. Gregory and Benedict were practical men, with an eye for the importance of ordinary things; and they combined this practical temperament with their religious and cultural activities. In particular, we owe it to St. Benedict that the monasteries were the homes of practical agriculturalists, as well as of saints and of artists and of men of learning. The alliance of science with technology, by which learning is kept in contact with irreducible and stubborn facts, owes much to the practical bent of the early Benedictines. Modern science derives from Rome as well as from Greece, and this Roman strain explains its gain in an energy of thought kept closely in contact with the world of facts.

Thirdly, in the non-political fields of art and learning, Constantinople had achieved a high standard. This achievement gave Western culture a constant incentive. It encouraged direct imitation, but also inspired people indirectly through the mere knowledge that such achievements existed. The Byzantines’ wisdom in the minds of people in the early Middle Ages played a role similar to Egyptian wisdom in the minds of the early Greeks. In both cases, the recipients probably had about as much actual knowledge of that wisdom as was good for them. They knew enough to recognize the kinds of standards that could be reached. But they did not know enough to be held back by fixed and traditional ways of thinking. As a result, in both cases, they went ahead on their own and did better. No account of the rise of the European scientific mentality can leave out some mention of the influence of Byzantine civilization in the background. In the sixth century, relations between the Byzantines and the West reached a crisis. This crisis contrasts with the influence of Greek literature on European thought in the fifteenth and sixteenth centuries. The two outstanding men who laid the foundations of the future in sixth-century Italy were St. Benedict and Gregory the Great. They show us at once how completely the Greek approach to a scientific mentality had fallen into ruin. We are at the zero point of scientific temperature. But the life’s work of Gregory and Benedict contributed elements to the reconstruction of Europe. These ensured that the reconstruction, when it came, would include a more effective scientific mentality than that of the ancient world. The Greeks were too theoretical. For them, science was an offshoot of philosophy. Gregory and Benedict were practical men who recognized the importance of ordinary things. They combined this practical temperament with their religious and cultural activities. In particular, we owe it to St. Benedict that monasteries were homes to practical farmers, as well as saints, artists, and men of learning. The alliance between science and technology keeps learning in contact with irreducible and stubborn facts. That alliance owes much to the practical bent of the early Benedictines. Modern science comes from Rome as well as Greece. This Roman influence explains its gain in energy of thought, kept in close contact with the world of facts.

But the influence of this contact between the monasteries and the facts of nature showed itself first in art. The rise of Naturalism in the later Middle Ages was the entry into the European mind of the final ingredient necessary for the rise of science. It was the rise of interest in natural objects, and in natural occurrences, for their own sakes. The natural foliage of a district was sculptured in out-of-the-way spots of the later buildings, merely as exhibiting delight in those familiar objects. The whole atmosphere of every art exhibited a direct joy in the apprehension of the things which lie around us. The craftsmen who executed the late medieval decorative sculpture, Giotto, Chaucer, Wordsworth, Walt Whitman, and, at the present day, the New England poet Robert Frost, are all akin to each other in this respect. The simple immediate facts are the topics of interest, and these reappear in the thought of science as the ‘irreducible stubborn facts.’

But the influence of contact between the monasteries and the natural world first appeared in art. The rise of Naturalism in the later Middle Ages brought the final ingredient needed for science into European thought. People became interested in natural objects and events for their own sake. Local plants were carved in out-of-the-way places on later buildings, simply to express delight in these familiar things. Every art reflected a direct joy in observing the things around us. In this respect, the craftsmen who made late medieval decorative sculptures are all akin to Giotto, Chaucer, Wordsworth, Walt Whitman, and, today, the New England poet Robert Frost. All take an interest in simple, immediate facts. These facts reappear in scientific thought as the ‘irreducible stubborn facts.’

The mind of Europe was now prepared for its new venture of thought. It is unnecessary to tell in detail the various incidents which marked the rise of science: the growth of wealth and leisure; the expansion of universities; the invention of printing; the taking of Constantinople; Copernicus; Vasco da Gama; Columbus; the telescope. The soil, the climate, the seeds, were there, and the forest grew. Science has never shaken off the impress of its origin in the historical revolt of the later Renaissance. It has remained predominantly an anti-rationalistic movement, based upon a naïve faith. What reasoning it has wanted, has been borrowed from mathematics which is a surviving relic of Greek rationalism, following the deductive method. Science repudiates philosophy. In other words, it has never cared to justify its faith or to explain its meanings; and has remained blandly indifferent to its refutation by Hume.

European thought was now ready for a new venture. There is no need to recount in detail the events that marked the rise of science: the growth of wealth and leisure, the expansion of universities, the invention of printing, the capture of Constantinople, Copernicus, Vasco da Gama, Columbus, and the telescope. The soil, the climate, and the seeds were there, and the forest grew. Science has never shaken off the stamp of its origins in the historical revolt of the later Renaissance. It has remained largely a movement against rationalism, based on a naïve faith. When science has needed reasoning, it has borrowed it from mathematics. Mathematics is a surviving relic of Greek rationalism and follows the deductive method. Science rejects philosophy. In other words, science has never cared to justify its faith or explain what it means. It has remained calmly indifferent to Hume’s refutation of it.

Of course the historical revolt was fully justified. It was wanted. It was more than wanted: it was an absolute necessity for healthy progress. The world required centuries of contemplation of irreducible and stubborn facts. It is difficult for men to do more than one thing at a time, and that was the sort of thing they had to do after the rationalistic orgy of the Middle Ages. It was a very sensible reaction; but it was not a protest on behalf of reason.

Of course, the historical revolt was fully justified. It was needed. More than needed, it was absolutely necessary for healthy progress. The world needed centuries to study stubborn facts that could not be reduced to simpler terms. People find it difficult to do more than one thing at a time. And studying facts was what they had to do after the excessive rationalism of the Middle Ages. It was a very sensible reaction, but it was not a protest in defense of reason.

There is, however, a Nemesis which waits upon those who deliberately avoid avenues of knowledge. Oliver Cromwell’s cry echoes down the ages, ‘My brethren, by the bowels of Christ I beseech you, bethink you that you may be mistaken.’

But those who deliberately avoid opportunities to learn will face consequences. Oliver Cromwell’s cry still echoes through the ages: ‘My brothers, for Christ’s sake, I beg you to consider that you may be mistaken.’

The progress of science has now reached a turning point. The stable foundations of physics have broken up: also for the first time physiology is asserting itself as an effective body of knowledge, as distinct from a scrap-heap. The old foundations of scientific thought are becoming unintelligible. Time, space, matter, material, ether, electricity, mechanism, organism, configuration, structure, pattern, function, all require reinterpretation. What is the sense of talking about a mechanical explanation when you do not know what you mean by mechanics?

Science has now reached a turning point. The once stable foundations of physics have broken apart. At the same time, physiology is establishing itself as a useful body of knowledge for the first time, rather than a heap of scraps. The old foundations of scientific thought are becoming impossible to understand. Time, space, matter, material, ether, electricity, mechanism, organism, configuration, structure, pattern, and function all need to be reinterpreted. What sense is there in talking about a mechanical explanation when you do not know what you mean by mechanics?

The truth is that science started its modern career by taking over ideas derived from the weakest side of the philosophies of Aristotle’s successors. In some respects it was a happy choice. It enabled the knowledge of the seventeenth century to be formularised so far as physics and chemistry were concerned, with a completeness which has lasted to the present time. But the progress of biology and psychology has probably been checked by the uncritical assumption of half-truths. If science is not to degenerate into a medley of ad hoc hypotheses, it must become philosophical and must enter upon a thorough criticism of its own foundations.

The truth is that modern science began by adopting ideas from the weakest side of the philosophies of Aristotle’s successors. In some respects, this was a fortunate choice. It made it possible to express seventeenth-century knowledge of physics and chemistry in a complete, systematic form. That achievement has lasted to the present day. But the progress of biology and psychology has probably been held back by the uncritical acceptance of half-truths. If science is not to become a jumble of ad hoc hypotheses, it must become philosophical. It must thoroughly examine its own foundations.

In the succeeding lectures of this course, I shall trace the successes and the failures of the particular conceptions of cosmology with which the European intellect has clothed itself in the last three centuries. General climates of opinion persist for periods of about two to three generations, that is to say, for periods of sixty to a hundred years. There are also shorter waves of thought, which play on the surface of the tidal movement. We shall find, therefore, transformations in the European outlook, slowly modifying the successive centuries. There persists, however, throughout the whole period the fixed scientific cosmology which presupposes the ultimate fact of an irreducible brute matter, or material, spread throughout space in a flux of configurations. In itself such a material is senseless, valueless, purposeless. It just does what it does do, following a fixed routine imposed by external relations which do not spring from the nature of its being. It is this assumption that I call ‘scientific materialism.’ Also it is an assumption which I shall challenge as being entirely unsuited to the scientific situation at which we have now arrived. It is not wrong, if properly construed. If we confine ourselves to certain types of facts, abstracted from the complete circumstances in which they occur, the materialistic assumption expresses these facts to perfection. But when we pass beyond the abstraction, either by more subtle employment of our senses, or by the request for meanings and for coherence of thoughts, the scheme breaks down at once. The narrow efficiency of the scheme was the very cause of its supreme methodological success. For it directed attention to just those groups of facts which, in the state of knowledge then existing, required investigation.

In the remaining lectures of this course, I will trace the successes and failures of particular views of cosmology. These are the views European thinkers have adopted over the last three centuries. General climates of opinion last for about two or three generations, or sixty to a hundred years. Shorter waves of thought also play on the surface of this tidal movement. We will therefore find changes in the European outlook that slowly reshape each successive century. Yet throughout this period, one scientific view of the universe remains fixed. It assumes that the ultimate fact is an irreducible, brute matter, or material, spread throughout space in constantly changing arrangements. In itself, this material is without sensation, value, or purpose. It simply does what it does, following a fixed routine imposed by external relations. These relations do not arise from the nature of the material itself. I call this assumption ‘scientific materialism.’ I will also challenge it as entirely unsuited to the scientific situation we have now reached. The assumption is not wrong if it is properly understood. Suppose we limit ourselves to certain kinds of facts, separated from the full circumstances in which they occur. The materialist assumption expresses these facts perfectly. But the scheme breaks down as soon as we go beyond this abstraction. It breaks down whether we use our senses more subtly or seek meaning and coherence in our thoughts. The scheme’s narrow effectiveness was the very reason for its great success as a method. It directed attention to precisely those groups of facts that needed investigation, given the knowledge available at the time.

The success of the scheme has adversely affected the various currents of European thought. The historical revolt was anti-rationalistic, because the rationalism of the scholastics required a sharp correction by contact with brute fact. But the revival of philosophy in the hands of Descartes and his successors was entirely coloured in its development by the acceptance of the scientific cosmology at its face value. The success of their ultimate ideas confirmed scientists in their refusal to modify them as the result of an enquiry into their rationality. Every philosophy was bound in some way or other to swallow them whole. Also the example of science affected other regions of thought. The historical revolt has thus been exaggerated into the exclusion of philosophy from its proper rôle of harmonising the various abstractions of methodological thought. Thought is abstract; and the intolerant use of abstractions is the major vice of the intellect. This vice is not wholly corrected by the recurrence to concrete experience. For after all, you need only attend to those aspects of your concrete experience which lie within some limited scheme. There are two methods for the purification of ideas. One of them is dispassionate observation by means of the bodily senses. But observation is selection. Accordingly, it is difficult to transcend a scheme of abstraction whose success is sufficiently wide. The other method is by comparing the various schemes of abstraction which are well founded in our various types of experience. This comparison takes the form of satisfying the demands of the Italian scholastic divines whom Paul Sarpi mentioned. They asked that reason should be used. Faith in reason is the trust that the ultimate natures of things lie together in a harmony which excludes mere arbitrariness. It is the faith that at the base of things we shall not find mere arbitrary mystery. The faith in the order of nature which has made possible the growth of science is a particular example of a deeper faith. This faith cannot be justified by any inductive generalisation. It springs from direct inspection of the nature of things as disclosed in our own immediate present experience. There is no parting from your own shadow. To experience this faith is to know that in being ourselves we are more than ourselves: to know that our experience, dim and fragmentary as it is, yet sounds the utmost depths of reality: to know that detached details merely in order to be themselves demand that they should find themselves in a system of things: to know that this system includes the harmony of logical rationality, and the harmony of aesthetic achievement: to know that, while the harmony of logic lies upon the universe as an iron necessity, the aesthetic harmony stands before it as a living ideal moulding the general flux in its broken progress towards finer, subtler issues.

The success of the scheme has harmed the various currents of European thought. The historical revolt was against rationalism because the rationalism of the scholastics needed a sharp correction through contact with brute fact. But Descartes and his successors accepted scientific cosmology at face value, and this shaped the entire development of the philosophical revival. The success of scientists' fundamental ideas confirmed their refusal to modify them after examining whether they were rational. Every philosophy had to swallow those ideas whole in one way or another. Science also set an example that affected other areas of thought. The historical revolt has thus gone too far, excluding philosophy from its proper role of bringing the various abstractions of methodical thought into harmony. Thought is abstract, and the greatest fault of the intellect is its intolerant use of abstractions. Returning to concrete experience does not entirely correct this fault. After all, you can attend only to those aspects of your concrete experience that fit within some limited scheme. There are two ways to purify ideas. One is through impartial observation with the bodily senses. But observation is selective. So it is difficult to move beyond a scheme of abstraction that has been successful over a wide enough range. The other method is to compare the various schemes of abstraction that are well founded in our different kinds of experience. This comparison meets the demands of the Italian scholastic theologians whom Paul Sarpi mentioned. They asked that reason should be used. Faith in reason is trust that the fundamental natures of things fit together in a harmony that leaves no room for mere arbitrariness. It is the faith that we will not find mere arbitrary mystery at the base of things. Faith in the order of nature has made the growth of science possible. It is one example of a deeper faith. This deeper faith cannot be justified by any generalization drawn from observed cases. It comes from directly examining the nature of things as revealed in our own immediate, present experience. You cannot part from your own shadow. To experience this faith is to know that, in being ourselves, we are more than ourselves. It is to know that our experience, dim and fragmentary as it is, still reaches the utmost depths of reality. It is to know that separate details must belong to a system of things simply to be themselves. It is to know that this system includes the harmony of logical rationality and the harmony of aesthetic achievement. It is to know that logical harmony rests on the universe as an iron necessity. Aesthetic harmony, by contrast, stands before the universe as a living ideal. It shapes the general flow of things as it progresses, by fits and starts, toward finer, subtler outcomes.