In the foregoing pages we have given a representative selection from the scientific writings of the Alexandrian and Graeco-Roman periods.... With astonishment we find ourselves on the threshold of modern science. Nor should it be supposed that by some trick of translation the extracts have been given a delusive air of modernity. Far from it. The vocabulary of these writings and their style are the source from which our own vocabulary and style have been derived. There is no illusion here. With the science of Alexandria and of Rome we are in very truth on the threshold of the modern world. When modern science began in the sixteenth century it took up where the Greeks left off. Copernicus, Vesalius, and Galileo are the continuators of Ptolemy, Galen, and Archimedes.

But, if our first impression is favourable, it is quickly succeeded by a strange doubt. The Greeks and Romans stood on the threshold of the modern world. Why did they not push open the door? The situation is paradoxical in the extreme. We have here surveyed a period of some five hundred years, from the death of Aristotle in 322 the death of Galen in A.D.199. But long before the end of this period the essential work had been done. Before the end of the third century B.C.Theophrastus, Strato, Herophilus and Erasistratus, Ctesibius and Archimedes had done their work. In the Lyceum and the Museum the prosecution of research had reached a high degree of efficiency. The capacity to organize knowledge logically was great. The range of positive information was impressive, the rate of its acquisition more impressive still. The theory of experiment had been grasped. Applications of science to various ingenious mechanisms were not lacking. It was not, then, only with Ptolemy and Galen that the ancients stood on the threshold of the modern world. By that late date they had already been loitering on the threshold for four hundred years. They had indeed demonstrated conclusively their inability to cross it.

Here, then, we have evidence of a real paralysis of science. During four hundred years there had been, as we have seen, many extensions of knowledge, much reorganization of the body of knowledge, fresh acquisitions of skill in exposition. But there was no great forward drive, no general application of science to life. Science had ceased to be, or had failed to become, a real force in the life of society. Instead there had arisen a conception of science as a cycle of liberal studies for a privileged minority. Science had become a relaxation, an adornment, a subject of contemplation. It had ceased to be a means of transforming the conditions of life. Even such established arts as were adapted to keeping society in repair - professions like those of the architect and the medical doctor - were on the edge of respectability. They approached it only to the extent to which the practitioner could be regarded as the possessor of purely theoretical knowledge by which he directed the labour of others.

When we look for the causes of this paralysis it is obvious that it is not due to any failure of the individual. The endeavour to explain great social movements by the psychology of individuals is one of the crippling errors of our time. No, while science as a whole became a prey to creeping paralysis, there was no lack of individual talent, no lack of individual genius, as these pages abundantly show. The failure was a social one and the remedy lay in public policies that were beyond the grasp of the age. The ancients rigorously organized the logical aspects of science, lifted them out of the body of technical activity in which they had grown or in which they should have found their application, and set them apart from the world of practice and above it. This mischievous separation of the logic from the practice of science was the result of the universal cleavage of society into freeman and slave. This was not good either for practice or for theory. As Francis Bacon put it, surveying according to the knowledge of his day the same facts that we have here surveyed, if you make a vestal virgin of science you must not expect her to bear fruit. The fruits of a general improvement in the material conditions of life and of a general emancipation of society from  superstition were not such as could be produced by such a reverend maid as ancient science became in its decline.

With us to-day the concept of science carries with it the idea of a transforming power over the conditions of life. While we properly defend the ideal of science as involving a disinterested devotion to truth - indeed this ideal is itself a product of social history and has never shone more brightly than among those of our contemporaries who recognize and acknowledge the social responsibilities of scientific power - we recognize at the same time that from the well-head of pure science flow fertilizing streams which serve industry. We are nearly all Baconian enough to regard science as not only knowledge of nature but as power over nature. The complementary truth, that industry promotes science as much as science promotes industry, is also part of our usual view. The mutual action of science upon life and life upon science is a basic element in our consciousness. It was not so when antiquity was in its decline. Science was for the study and the few. Power over nature was increased, so long as this proved possible, by increasing the number of slaves.




The failure of ancient science was in the use that was made of it. It failed in its social function. Even when the acquisition of slaves became more and more difficult the ancients still did not turn to a systematic application of science to production. It is not claimed that such applications never occurred…. But the general truth remains that ancient society had set in a mould which precluded the possibility of an effective search for power other than the muscles of slaves. The dependence of society on the slave is everywhere reflected in the consciousness of the age. For Plato and Aristotle in the fourth century B.C.i t was axiomatic that civilization could not exist without slaves. …

… (Medieval) civilization, arising out of the grave of slave society, soon flowered in a series of new inventions which transformed the economic basis of life.

IX century - The modern harness of the saddle-horse, with saddle, stirrups, bit, and nailed iron shoes.

X century - The modern harness of the draft-animal, with shoulder-collar, shafts, disposition in file and nailed shoes.

XII century - Watermill, windmill, mechanical saw, forge with tilt-hammer, bellows with stiff boards and valve, window-glass and glazed windows, the domestic chimney, candle and taper, paved roads, the wheel-barrow.

XIII century - Spectacles, wheeled-plough with mould-board, rudder.

XIV century - Lock-gates on canals, gunpowder, grandfatherclock, plane.

XV century - Printing.

… The chief glory of the later Middle Ages was not its cathedrals or its epics or its scholasticism: it was the building for the first time in history of a complex civilization which rested not on the backs of sweating slaves or coolies but primarily on non-human power.'

It has been naively taught, and is still sometimes naively believed, that the science of the Renaissance arose because Greek books from Constantinople arrived in western Europe. If this were the whole truth of the matter, we might well ask why the modern world was not born in Alexandria, or in Rome, or in Constantinople, where the old books survived. There is another aspect of the truth to be considered. Graeco-Roman science was good seed, but it could not grow on the stony ground of ancient slave society. The technical revolution of the Middle Ages was necessary to prepare the soil of western Europe to receive the seed, and the technical device of printing was necessary to multiply and broadcast the seed before the ancient wisdom could raise a wholesome crop.

… The peoples of western Europe had the advantage of living in a region where three of the important natural resources for the simpler forms of power were more abundant than in the lands of the older civilizations. The climate gave them more continuous vegetation, and thus allowed them to have more work-animals; it also gave them wind enough at all seasons to drive the ships on their seas and simple windmills on land; and the abundance of rain, combined with the absence of a dry season, enabled them to have widespread small-scale water-power on their streams. Thus, when they had learned how to make use of these resources, they built up a society in which humans were freed from a large part of the necessary drudgery. These technical advances led to social changes; for the chattel slave and the galley slave were no longer needed, and those crude forms of compulsory labour slowly disappeared. They were replaced partly by serfdom and  partly by the organizations of craftsmen; both of which merged later into the wage system of modern capitalistic democracy.




The creators of modern science in the sixteenth century, working again in an age of technical advance in which ancient social abuses were being swept away, recapture the humanitarian as well as the scientific zeal of old Ionia. Reading their pages we seem to breathe a purer and freer air.

… Perhaps the most decisive defeat of the scientific spirit in antiquity had been the loss of the sense of history. History is the most fundamental science, for there is no human knowledge which cannot lose its scientific character when men forget the conditions under which it originated, the questions which it answered, and the function it was created to serve. A great part of the mysticism and superstition of educated men consists of knowledge which has broken loose from its historical moorings. It is for this reason that we have stressed the sketches of civilization given by Democritus and Lucretius and characterized them as the most important achievement of ancient science.

The process by which the knowledge of one generation can be transformed into the superstition of the next can conveniently be studied by passing from the De Rerum Natura of Lucretius to the Aeneid of Virgil, though Virgil's motive in stringing oracles, omens, portents, and miracles so thick on his epic thread is no doubt a complicated one …. It can also be studied in what the learning of Alexandria made of the Hebrew scriptures when they were translated into Greek. It might have been expected that the addition to Greek literature of the historical record of a strange people would deepen their historical sense. In fact the historical interpretation of the Hebrew scriptures is a product of recent times. The classical world had turned its own history into myth before it acquired a knowledge of the Old Testament and it treated it unhistorically from the first. It would hardly be possible to be more learned than Origen (A.D.186-254), who applied all the resources of Alexandrian scholarship to the work of biblical criticism. But in the absence of any historical sense it is admitted that his interpretations are entirely arbitrary. What history lost theology gained, and human history dwindled to the proportions of a small act in a cosmic drama….

The greatest achievement of modern science has been the rebirth of the historical sense. This is a subject on which we cannot enter here, but a brief allusion to it will form the appropriate conclusion to our book. We have mentioned the names of some of the great founders of modern science,- Copernicus, Vesalius, Galileo, Stevin, and others. The man who gave supreme expression to the spirit of this age was the Englishman, Francis Bacon (1561-1626). He turned on the whole question of the revival of science an acute historical sense, remarkable for his day and little understood by his successors.The body of the Baconian writings constitutes one great comment on human history, the sense of which is that the real history of humanity can only be written in terms of man's conquest over his environment. His subject was, in his own words, The Interpretation of Nature and Man's Dominion over it. He penetrated behind the veil of politics to the economic reality and judged man's past achievement and future prospects in terms of his mastery over nature, not denying other aspects of his culture but relating them to this basic fact.

The sense of the reality of time, the reality of historical change, and the influence exercised by man over his own destiny, were contributions to the profound philosophy of Vico (1668-1744), who, in the light of his intuition that Man makes his own History, was justified in his claim to have made of history The New Science. Bacon glimpsed the truth that man makes his mental history in the process of conquering his world. Vico saw more clearly than Bacon that this is not an achievement of individual man but of society. In the fundamental institutions of human society he saw the instruments whereby man, who began as a brute, has transformed himself into a civilized being.



In one sense Greek science may be considered a failure. The conditions needed to insure the continuous growth of science did not exist, and were never created, in the ancient world. There were certainly doctors, architects and engineers who recognized the practical importance of some aspects of their theoretical inquiries. Yet their efforts were uncoordinated, and no systematic attempt to explore the practical applications of science was made. Of the possible raisons d'etre of science, the idea that it could be of practical use, while not totally absent, took second place to the idea that the study of nature contributed to knowledge and understanding-which are valuable for their own sakes. A large part of ancient natural science never fully emancipated itself from philosophy: but to put it that way is to speak from a modern, not an ancient, standpoint. To the ancients, philosophy generally included physics or the inquiry concerning nature as one of its three main branches, and the chief motive for that inquiry was the philosophical one in the literal sense of the 'love of wisdom'. So we find some of the doctors and architects assimilating their studies to philosophy, and if this was in part because of the superior social position and prestige of philosophy, it also reflects the belief that their principal goal was knowledge. Science was less a means to an end, than an end in itself. The life devoted to study or 'contemplation' is the supremely happy life. Knowledge is its own reward and correspondingly less attention was paid to the idea of the benefits that might accrue from its application to practical purposes, The tendency to value material below moral and intellectual goods is common in the writings of ancient moral philosophers, and although one may doubt how far their opinions were typical of ancient society as a whole, the lack of any sustained attempt to justify scientific inquiry in terms of the increased material prosperity to which it might lead is one of the most striking differences between the ancient view and that of the nineteenth and twentieth centuries. But it is not merely the case that ancient science reflects ancient values. Science itself was, in at least three ways, not morally neutral. First Plato's idea (Timaeus 47 bc), that contemplation of the orderly movements of the heavenly bodies helps us to regularize the disorderly movements of our own soul, is repeated in a rather simpler form by later writers. Ptolemy, for instance, believed that astronomy improves men's characters. Secondly, there were writers who, without necessarily claiming that science makes men better, maintained that nature is orderly, beautiful and good (whether or not they also postulated an intelligent and benevolent deity responsible for its design). Thirdly, even among those who rejected in the strongest possible terms the idea that the world is the product of design, there were some who justified the study of nature on what are, broadly speaking, ethical grounds. Thus the Epicureans shared the view of their opponents, the Stoics, that some knowledge of natural phenomena is necessary to insure the peace of mind without which a man cannot be truly happy.

But if the study of nature is often linked to, or even part of, moral philosophy, this generalization, like so many others, needs qualification…. Physics, mathematics and biology were often conceived as parts of a comprehensive philosophy, Yet they could be, and often were, studied as independent disciplines with no commitment on the part of the researcher to any overall cosmological or ethical theses….

Moreover there were those who deliberately dissociated themselves from the philosophers, though not on ethical grounds, so much as on epistemological or methodological ones. Already in the period before Aristotle there had been doctors who rejected the philosophers' methods of inquiry as mere speculation and later medical theorists, particularly among the Empiricists, sometimes did the same. Criticism of the philosophers for placing too much reliance on abstract argument is part of the continuing debate on the roles of reason and sensation, argument and experience, which runs through the work of many ancient scientists….

The social and intellectual framework within which ancient scientists worked differed in certain fundamental respects from that of their modern counterparts. There was no acknowledged place in ancient thought, or in ancient society, for science, or for the scientist, as such. The investigators performed different social roles as doctors or architects or teachers. Disagreements concerning the 'inquiry about nature' were not merely a matter of the differing motives and philosophical allegiances of the individuals concerned, but directly concerned the types of question to be investigated. For some nature was everywhere purposeful, but others questioned teleology and final causes or rejected them outright, while still seeking order and regularities expressible as general laws.

But despite many important differences, the relevance of the work of the ancients to what we mean by science remains. This is true in one obvious way in that in such fields as optics, statics, astronomy and anatomy, the ancients achieved certain positive results (admittedly in the elementary parts of those disciplines) which provided a basis on which later scientists could build directly. But even more important was the creation, elaboration and exemplification of models of the inquiry concerning nature itself. Two key methodological principles, the application of mathematics to the investigation of natural phenomena, and the notion of deliberate empirical research, go back to the earlier period that culminates in Aristotle. What the later period we have considered in this study provides is, above all, examples of the application of these principles in practice. Euclid's Elements was the chief model of an axiomatic, deductive system. Archimedes in statics and hydrostatics, and Apollonius and Ptolemy in astronomy, represent the most successful attempts to bring mathematical methods to bear on the discussion of physical problems. As for the idea of research, we find a powerful statement of this in Erasistratus, and among others such as Theophrastus, Strato, Herophilus and Hipparchus, who might be mentioned, Ptolemy and Galen provide excellent examples of the practice of historia. Both men not only carried out extensive programmes of observation, but also conducted deliberate tests, Ptolemy in optics, and Galen in his investigations of the nervous system and other vital functions.

The criticism is often made that the fatal shortcoming of Greek science was the failure to appreciate the importance of experimentation. But that is an oversimplification. It is true that the use of the experimental method is confined to certain problems and to certain individuals, but the same may also be said of the idea of the mathematization of physics. Here too the principle was known, and it is not hard to identify, with the benefit of hindsight, the opportunities for its application that were missed. In neither case is there a fundamental difference in kind, however great the differences in degree, between the methods of ancient and modern science. But both these shortcomings in ancient science reflect, and were aggravated by, the more basic organizational weakness to which I have alluded, the fact that the conditions needed to insure the continuous growth of science never existed in the ancient world. The relative isolation of those who engaged in scientific investigation acted as an obstacle to the systematic application of methodological ideas and was a constant threat to the continuity of inquiry in most fields of science. Thus we know of no significant contribution to the study of dynamics between Hipparchus, in the second century B.C., and Philoponus and Simplicius in the sixth century A.D.-although both these later writers generally provide full information concerning the work of their predecessors. Optics, botany and embryology too suffered from long periods of stagnation (in several cases the work done in the fourth or third century B.C. was never surpassed) and the same can be said of most other branches of investigation with the exception of elementary mathematics, astronomy and medicine. Moreover, even within the same generation the lack of communication between men who were interested in different aspects of the inquiry concerning nature can be illustrated by comparing the statements that Epicurus made on problems in astronomy with the theories of some of his own contemporaries. Given the conditions under which scientists worked, it is hardly surprising that some of the most important theories, discoveries and methods of ancient science were sometimes ignored or not followed up with any vigour. Yet the neglect that some of the most important ideas produced by the ancients suffered from in antiquity does not diminish the value of those ideas in themselves. The weakness of the social and ideological basis of ancient science, becomes more obvious in the decline we have outlined in this chapter. But when scientific investigation was revived in the West, it was a genuine rebirth, not merely in that the work of the great ancient scientists was rediscovered, but also and more particularly in that there was a return to the spirit of inquiry of ancient science and to the models of method that it provided.