ultimate criterion of any proposition, however learned.^t As to the continuity, what he could absorb through intellectual osmosis at the Ecole should seem even more telling. He could hardly be unfamiliar with the often-quoted passage in Eustel’s famed analysis of Greco-Roman social history:

Even more important should seem for the formation of Duhem the historian the chief message of Fustel’s classic. Its author argued that the three great social revolutions of classical times the dethroning of theocratic kings, the breaking up of the gens as a family, and the entering of the plebs into the political life —were but vehicles of a continuity: the gradual extension of the idea of mutual responsibility which found its fulfillment in the advent of Christianity. Much the same was argued with respect to modern history by Gabriel Monod, also a professor of history at the Ecole. In launching in 1876 the Revue historique, an organ more secular than the older Revue des questions historiques, Monod exhorted its future contributors to see the logical connection which secures continuity even across such chasms as the French Revolution, the Protestant Reformation, and the Renaissance. As to contemporary interest in history, Monod merely had to register it:

‘Our century is the century of history.’³

The thrust of the phrase was evolution through time. Duhem’s fondness for the evolutionary perspective was certainly evidenced in his high esteem for the famed study of modern French history by H. Tame,⁴ a protagonist of Darwinism in political as well as intellectual history. Not that the common sense of Duhem would have subscribed to evolution in terms of blind chance. He emphatically rejected the portrayal of human history as seen through the inexorable struggle of the survival of the fittest which leaves no room for purpose. As a professor, who had to preside over examinations for licence, which included even for students of physics the topic of evolution, he was wont to deliver a scathing expos6

l.La science allemande, 1915 (2), p. 90. Fustel attached even greater importance to the impartiality with which the historian was to read the documents. See his inaugural lecture of his course on medieval history at the Sorbonne, the text of which was immediately printed in Revue politique etlittdraire 8 (Feb. 8, t879):745-51 ;especially p.746.

2. Quoted from the English translation, The Ancient City: A Study on the Religion, Laws, and Institutions of Ancient Greece and Rome, by W. Small (4th ed.; Boston: Lee & Shepard, 1882, p. 13) of Fustel’s classic, La citd antique, first published in 1864; it had already gone through a dozen editions by the time Duhem completed his studies at the Ecole.

3. G. Monod, ‘Du progr~s des etudes historiques en France depuis le XVIe si~cle,’ Revue historique 1 (1876):5-38;see p. 27.

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In Duhem’s case the crucible was the superhuman effort he expended over a dozen years to track down and set forth that record in its overwhelming and wholly unsuspected richness, In that sense too he was a very special historian. However, he would not have become a historian of physics in any special sense had his interest in physics not been very special. The special perspective of Duhem the historian was set by his theory of physical science according to which physics, having commonsense data and truths as its basis, was to remain, for its own good, free of hypotheses about the internal nature of matter. Duhem believed, and this is what made him a historian, that the historical survey of any major topic of physics would support the correctness of that perspective anchored in common sense. Tellingly, his Thaite~ d’Energ~tique, the great synthesis of his work in physics, began with a reference to his historical researches. In speaking of the final justification of the criteria which in his view had to guide the choice of physicist among various methods, he declared:

The essays which Duhem published between 1893 and 1897 on the history of atomic dotation, of gravitational theories, of mechanical models, and on the evolution of science since the 17th century, have therefore an interest of their own. Written as they were in the same years when Duhem advanced a philosophically articulated view of what he was supposed to do as a physicist, who satisfied the dictates of logic and common sense, those essays also mark the making of Duhem the historian of physics in that specific sense. Apart from showing the specifically interpretative interest of their author in the history of his subject matter, physics, those essays also show his bent on rigor, another aspect of his interest in physics. Rigor in matters historical means above all a reliance on original sources. Such a reliance is an immediate antidote against being trapped in the perennial disease of repeating clich6s, let alone of making up history. Those essays earned for Duhem the reputation of being an expert on the history of physics so effectively that soundings were made from high levels about his availability for the chair of the history of science at the Collage de France.⁸ In reading those essays one meets

6. Translated from Duhem’s review of the first volume of Dufourcq’s L ‘avenir du christianisme. Introduction. La vie et la pensde chrdtienne dans le passe’ (Paris: Blood et Cie, 1904,

x + 7⁹⁹pp) in RQSc 55 (1904):252-54.

7.1911(1), 1:5.

8. See Jordan, ‘Duhem,’ p. 162, and Ch. 4.

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right direction. The kind of histories of physics which Duhem was to write on such a basis was well exemplified in the first half of his Evolution de la m&anique. There in fourteen chapters he gave a carefully documented account of a progress stretching from Aristotle to Hertz’s mechanics and Kelvin’s vortex atom. Well over three-fourths of that first half were devoted to the last hundred years, starting with the place of the idea of virtual velocities in Lagrange’s statics. Duhem was a physicist’s historian not an antiquarian. For him remote stages in the history of exact science could not rival phases of its recent development. The importance which he assigned to the role of virtual velocities was a dictate of interpretation, a dictate imposed from the standpoint of theoretical physics. Not history but theoretical insight made Duhem perceive the striking similarity between the thermodynamic potential and the principle of virtual velocities, That the latter was the germ out of which Lagrangian mechanics arose was also a point which took more a theoretician than a historian to perceive.

In respect to clarity of insight, richness of historical data, and grasp of the essential those fourteen chapters surpassed anything available at that time as an overview of the history of mechanics, restricted as was the perspective.¹² Those familiar with Duhem’s essay from 1896 on the evolution of physics from the 17th century on were not surprised by his portrayal of the principal features of that development, which Duhem described above all as a genuine growth, an evolution. Being such a growth, it was to be open-ended. Then, as well as years later, Duhem was far from thinking that his thermodynamics or energetics was the last word in physics. He spoke of himself as he cautioned: ‘It would be quite presumptuous to imagine that the system for whose achievement the physicist works will escape the fate common to the systems that have preceded it and will merit lasting longer than they.’ 13 But precisely because that evolution was a genuine growth, the theoretician, mindful of the necessary imperfection of his product, did not have to despair: ‘each of the stages of this evolution is the natural corollary of the stages that have preceded it; it is the chief part of the stages which will follow it. Meditation upon this law has to be the theoretician’s solace.’¹⁴

Thus, although the faint echoing by the latest in mechanics, or energetics, of

some peripatetic notions could appear as a counterrevolution, especially to latter-

day Cartesians, it did not have to be viewed as something disruptive. While often

12. That historical part of Duhem’s Evolution de la mdcanique presented, with its emphasis on 19th-century developments, a startling contrast even to Mach’s Die Mechanik in ihrer Entwicklung (1883), a work in its 4th edition by 1901. Duhem may have first learned about the main points and general trend of Mach’s book through a review of it in BScM 10 (1886):

97-99, In that review, written by H. (Hermite?), pointed reference was made to virtual velocity as the basis of all questions concerning equilibria according to Lagrange’s Me’ canique analytique (see note 26 below), a work on which Mach heavily relied. Duhem confined his criticism of Mach’s work to a few factual details in the long review he wrote in 1903 of its French translation, 1903 (30). The half dozen letters, all brief and curteous, exchanged between Mach and Duhem, contain only generalities.

14. Ibid., p. 188.

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words for an age steeped in theology.²⁰ The histories of physics published in 1880s by J. C. Poggendorff,²¹ F. Rosenberger,²² and A. Heller²³ were hardly an improvement on the little which Duhem could find in the much earlier work of J. E. Montucla²⁴ with respect to the 14th and 15th centuries. Different was the case as he pursued G. Libri’s work, already in print for over sixty years, when he first quoted it in 1903. There he found a reference to Leonardo’s notion of virtual velocity, a matter, as he immediately noted, of ‘utmost importance.’²⁵ This meant the extension of the history of mechanics a hundred years farther back than Galileo, who was the start of that science in the historical introduction which Lagrange prefixed to his Mecanique analytique,²⁶ a work familiar to Duhem for some time. Beyond Leonardo there was in all appearance nothing to look for. The heavy lines which separated the section on the Greeks and the one on Leonardo

20. A subtle evidence of Mach’s contempt for the inedievals was his refusal to refer to them as such after he had to acknowledge Duhem’s findings on the medieval origins of statics and

on the medieval forerunners of Leonardo.

21. Poggendorff’s Geschichte der Physik, the text of his lectures at the University of Berlin (Leipzig: J. A. Barth, 1879), was available in French since 1883.

22. The three volumes of Rosenberger’s Die Geschichte der Physik (Braunschweig: F. Vieweg) were published between 1882 and 1890.

23. Heller’s Geschichte der Physik von Aristoteles his auf die neueste Zeit (1882) was reprinted in 1965 (Wiesbaden: M. S~ndig). Compared with these works, only superficial popularization of the subject could be found in the two-volume Histoire de Ia physique et de la chimie depuis les temps les plus reculds iusqu’iz nor jours (Paris: Firmin Didot Fr’eres, 1866-69) by Jean-Chr6tien-Ferdinand Hofer, a German-born French polygraph. His histoires of astronomy, botany, and mathematics were on the same level. The twelve volumes, comprising almost 3000 pages, of the Histoire des sciences marhdmariques et physiqoes, which Maximiien Marie, r6p~titeur at the Ecole Polyrechnique, published between 1883 and 1887 (Paris:

Gauthier-Villars), had their sumptuous printing as their only commendable feature. Scientific history for Marie existed in listing scientists in chronological order.

24. Jean-Etienne Montucla’s Histoire des mathe’matiques, first published in two volumes in

1758, saw a second edition in four volumes in 1799 (the increase relating mostly to 18th-

century developments), and a reprinting in 1968 (Paris: Blanchard).

25. See 1903 (16), p.475 and 1905 (11), p. 13. The reference was to Libri’s four-volume Histoire des sciences mathe’matiques en Italie depuis Ia Renaissance des lettresjusqu’4 Ia fin du xviie si~cle (Paris: J. Renouard, 1838-41). Duhem then quickly found out that Libri’s statement (3:27) was a summary of the less than one page on the topic in the Essai sur Icr ouvrages physico-mathe’matiques de Le’onard de Vinci, avec des fragments tirds de ses manoscrits, apportds de l’Italie (Paris: chez Duprat, An V 117971) of J. B. Venturi, professor of physics in the lyceum of Modena, who read sections of it before the Acad6mie des Sciences (Institut National des Sciences et Arts) as part of a general reporting on the artistic, scientific, and literary riches seized by French troops in Italy. The entire second half of the 56-page essay was on Leonardo’s life and painting (pp. 33-57). Concerning Leonardo’s physical science Venturi spoke ‘of a few nuggets in a heap of useless sand’ (p.5). Among these were Leonardo’s dicta on statics and on descent on an inclined plane, which Venturi summed up in two short chapters (pp. 17-2 1) with some references to the entries in the manuscripts. There was no hint whatever in Venturi’s essay about the possible indebtedness of Leonardo to some earlier writers.

26. J. L. Lagrange, Me’ canique analytique (new enlarged edition; Paris: Mine Ve Courcier,

1811), 1:221. Concerning the science of statics, Lagrange moved directly from Archimedes to

Stevin (ibid., p. 2).

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assault of schoolmen on the fortress of truth as a breakthrough which made them fall ‘to the bottom of a dark ditch where three centuries of work could not enrich the human mind with a single notion.’³³ While Duhem could easily see through such claims as far as philosophy, the arts, and social development were concerned, he could hardly guess that the claim was utterly hollow with respect to the sciences.

Nothing was therefore more natural for Duhem than to move directly from Archimedean statics to Leonardo and state: ‘The commentaries of the scholastics on the ‘mechanical problems’ of Aristotle do not add anything essential to the ideas of the Stagerite. In order to see these ideas issue in new offshoots and bear new fruit we must wait for the beginning of the 16th century,’ that is, Leonardo da Vinci. So began the second chapter in that 60-page-long first instalment on the origins of statics which Duhem wrote in the late spring and early summer of 1903 and which saw print in the October issue of the Revue des questions scientifiques. 34 Concerning the scholastics he did not refer to any commentary. Possibly he saw one or two in the printed works of the great scholastics, and satisfied himself that no scholastic, great or minor, offered on the question pages worth studying. As far as the sciences were concerned he saw no reason to challenge the shibboleth about the darkness of the Middle Ages. Certainly no such challenge was intimated in Libri’s history of the mathematical sciences in Italy³⁵ which Duhem took for a first guide. Again, there was no hint to scholastic predecessors of Leonardo in the introduction which Charles L. Ravaisson-Mollien wrote to his edition of Leonardo’s manuscripts in the Biblioth~que Nationale,³⁶ an edition on which Duhem heavily relied.

Duhem did not have to discover Cardan as a main link between Leonardo and Galileo, nor did he have to study manuscripts in order to form himself a fair idea of Cardan’s contributions. Long as that first instalment was and expressive of the two thousand years stretching from Aristotle to Cardan, it could be written

33. H. Tame, Histoire de la litte’rature anglaise (2d rev, enlarged ed.; Paris: Hachette, 1866-

78), 1:223. How far and wide Tame’s dictum was carried can easily be gathered from the fact that this five-volume work went through ten printings before the end of the 19th century. Effectively as such statements could be rebutted at that time by Catholic scholars with respect to philosophy and the arts, they hardly sounded convincing as they took up the sciences, mathematical and empirical. Good illustrations, of this ineffectiveness are the chapters ‘Les sciences math~matiques’ (pp. 3 13-28) and ‘Les sciences physiques et naturelles’ (pp. 32944) in Le treizi~me si~cle litte’raire et scientifique (Bruges: Soci6t~ de Saint Augustin, 1894) by Albert Lecoy de la Marche, one of the better works of that type.

34.Lesoriginesdelastatique, 1905(11), 1:13.

35. According to Libri, even mathematics, the only scientific field worth mentioning about the Middle Ages, was in ‘a deplorable state’ with the exception of some efforts made in Italy

(2:156-64).

36. Ravaisson-Mollien was concerned mainly with the origin and history of the material he edited in the long preface to the first of the six folio volumes of Les manuscrits de Le’onard de

Vinci (Paris: A. Quantin, 1881-91).

to Euclid, and added that those reflections refuted the view of Montucla (whose more than a hundred-year-old history of mathematical sciences in four volumes was still authoritative) according to whom the contents of that treatise were but the ‘stutterings of a nascent physics.’⁴⁰ On the contrary, Duhem remarked, the treatise was seminal in producing in medieval times reflections very crucial for the future of physics. Although Jordanus de Nemore was repeatedly mentioned in the April installment, readers of the Revue could hardly have expected to be told by Duhem in the July installment that they would now be treated to some ‘ingenious efforts whose fruitfulness has not yet been exhausted . . . We shall now see the Western mind get hold of debris [transmitted by the Arabsj . . . We shall assist at a work of transformation and organization, prodigiously intense and powerful, which will produce modern statics.’^4t After discussing Jordanus de Nemore over twenty pages Duhem declared:

In the October issue, which carried the story beyond Jordanus de Nemore to Leonardo da Vinci, Duhem began with the declaration: ‘Science does not know of spontaneous generation. Not even the most unforeseen discoveries have ever been made in all detail in the mind which generated them.’⁴³ Ominous words, especially if part of a story inching closer to that Galileo whose inclined plane had by then become the secular equivalent of Jacob’s ladder. Its mystique made itself felt in most varied contexts, such as, to speak only of those years, in Bergson’s Evolution cr~atrice, where it was spoken of as the very vehicle on which science descended upon the earth.⁴⁴ In the January 1905 issue Duhem threw down the gauntlet:

‘In the very entourage of Galileo, there was familiarity with that old writing [of Jordanus] whose statics on certain points surpasses all that was given on that subject by the Florentine geometer.’⁴⁵ Everything was now ready for calling a spade a spade, which Duhem did in the April issue. In pointing his finger at Descartes’s ‘prodigious arrogance, which saw only errors in the past,’ Duhem also evoked the guilt of modern times born in the spirit of Descartes who ‘in his bril

44. See Creative Evolution, authorized translation by A. Mitchell (New York: Modern Library, 1944), p. 364. The remark was all the more startling because Bergson was aware of Duhem as attested by his reference in the same work (p. 264) to Duhem’s Evolution de la me’canique, which Bergson quoted with approval on the question of qualities.

45. Les origines de Ia statique, 1:262.

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singled out rigid Averroism, so averse to science, as a distinctive feature of the 16th century. Long hallowed clich6s were unmasked as Duhem concluded the second installment which brought the history of statics up to Torricelli’s principle:

Looking in such a way at past developments was central to Duhem’s philosophy of science in which the last word belonged to the witness of history. Duhem obviously was elated that a hitherto unexplored terrain, the science of four centuries before Galileo, was providing massive evidence on behalf of his theory of physics. Herein lies a principal explanation of the all-consuming zeal with which, from the late Fall of 1903 on, he delved deeper and deeper into historical research. A case in point is the paragraph which brought to a close his analysis of Torricelli’s principle on the pressure of the air. In its unobjectionable form given to it by Torncelli, Duhem saw a classic illustration of the typical development of physics leading to pure formalism:

The last two installments published in April and July 1906 need not detain us. They dealt, with undeniable freshness though, with a phase of the story, stretching from Mersenne to Varignon in the early 18th century, a phase already explored in its essential features. But the grand conclusion of all five installments is worth recalling. It was introduced with Duhem’s graphic description of Vis, a river in the C~vennes, one of his favorite hiking grounds, which suddenly disappears in underground cavities, breaks to the surface again miles downstream, forms a stretch of a narrow gorge strewn with dry stones, before, at long last, it turns into a steady onrush of water.⁵¹ Such was in Duhem’s eyes the perfect image of the view according to which if there was any connection between Greek and Renaissance science, it was merely a long arid stretch: ‘Senseless history,’ Duhem cried out:

49. Ibid., p. 150.

51. For that passage in English translation see p. 148 above.

56. Les origines de la statique, 2:290.

57. Etudes sur Ldonard de Vinci, 1:1.

mechanics a magnitude of a connecting force is determined by an exact method.’ His vast perspective as a historian made Duhem look beyond the fact, however important in itself: ‘How much more this passage will command our attention when we shall have greeted the discoveries which it will suggest to Leonardo!’⁶⁵

The second additional chapter, and the last in the first volume of the Leonardo studies, was devoted to a survey of the writings of Albert of Saxony. ‘The list,’ Duhem concluded, ‘is very likely incomplete. It suffices however to give an idea of the intellectual activity of this great philosopher to register the popularity which he enjoyed at the start of the Renaissance, and finally to combat the unexplainable oblivion where he is left by those who are interested in the progress of human thought in the course of the Middle Ages.’⁶⁶ Duhem’s work challenged admirers of the Middle Ages no less than the devotees of the Renaissance. The challenge was above all a challenge to posterity, In the preface which Duhem wrote on July 27, 1906, to the first volume of his Leonardo studies, there is a paragraph which should strike today with its modernity (and With its moderation!) all those who take the notion of biological struggle. for survival for an (let alone for the) explanatory device of the history of scientific ideas and pride themselves on originality. ‘The mind of Leonardo,’ Duhem wrote,

The placing of Leonardo at mid-point of a sequence of authors ‘whom he has read and who have read him,’ to recall Duhem’s priceless phrase, was the move of a convinced evolutionist, though of the kind of evolutionist mindful of the supreme challenge posed by evolution. That challenge is the securing of what endures in the process of change. Thus for Duhem evolution did not stand for a series of haphazard saltations but for the cement which turns mere succession into solid coherence: ‘Between those whom he has read and who have read him, Leonardo stands in his true place. Connected with the past, the learning of which he gathered and on which he meditated, he remains no less attached to the future as one whose ideas fertilized science.’⁶⁸

In the first additional chapter there appeared, in a brief note, the name of

65. Etudes sur Le’onard de Vinci, 1:300. Here too Duhem, the historian, seemed to be a disciple of Fustel de Coulanges, according to whom the science of history did not reside in the documents but in the intellect reading them,and who also held that the historian must consider long epochs, lest his narration should degenerate into mere stories (see J. Herrick, The Historical Thought of Fustel de Coulanges lWashington: The Catholic University of America

Press, 19541 ,pp. 79-82).

66.EtudessurLe’onardde Vinci, 1:338.

67. Ibid., p. vi.

68. Ibid., p. vii.

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to the condemnation on March 8, 1277, by Etienne Tempier, Bishop of Paris, of 216 propositions, among them the one denying the possibility of the plurality of worlds. Duhem felt that ‘if we were to specify the birthdate of modern science, we would undoubtedly choose that year, 1277.’73 Such was the debut of a phrase, which he was to repeat emphatically in evidence of the importance he attributed not so much to a mere date but to the question of live birth, the fundamental precondition of all continuity, including the continuity of growth, be it biological or intellectual.

These three phrases anticipated the gist of the third volume of the Leonardo studies, possibly the most dramatic volume ever published on the history of science. Its more than 600 pages were reserved for the birth and transmission of two pivotal notions of physics, the law of the conservation of momentum and the law of free fall. The former saw birth under the name of impetus in the commentaries of Buridan to various works of Aristotle, a chief advocate of the eternity of the world and its motions. Aristotle was also the originator of that concept of motion in which the mover had to be in continuous contact with the thing moved. Hence, in the Aristotelian discourse the Prime Mover (not unambiguously distinct from the world) had to remain in contact, however intellectualized, with the outermost of the heavenly orbs in order to secure the motion of all celestial bodies and through them all motion below the moon’s orb. To part with such an explanation of motion demanded the recognition of the absurdity of the claim that, say, the flight of a projectile was due to the push of the air which closed in behind it almost as if somebody was to lift himself by his own bootstraps. No less needed was a shift in broader cosmological outlook concerning the very source of motion. The Christian view of creation provided that shift and also provided Buridan with his favorite account of the start of all physical motion. Buridan was fully aware that the view very much moulded his reflections. It was also a view which withstood any rational objection that reason could think of:

The crucial importance of this new cosmic outlook was not lost on Duhem. He wanted the reader of the third volume of his Etudes to be ready for a drama as soon as he started reading the Introduction to it: ‘If one wanted to separate with a

73. Ibid., p. 412. The statement forms part of Note F. In the previously unpublished essay, ‘Leonard de Vinci et la pluraliai des mondes,’ which forms ch. 2 of the volume, Duhem discusses (pp. 75-82) in detail the various propositions condemned by Tempier without,however, attributing to his decree an epoch-making significance.

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January-March issue of the Bulletin Italien, he had been engaged for six years in a heroic pioneering study of the history of science in medieval and Renaissance centuries. He had six more years of work allotted to him, as he would have certainly put it, by Providence. His balanced view of Galileo’s genius was, contrary to a rather slanted claim, not the product of his final and mature view, a sort of retraction.⁷⁹ As a historian, no less than as a philosopher, Duhem showed a surprisingly high degree of ‘maturity’ at a relatively early stage of his investigations —physical, philosophical, and historical. Nor was maturity ever lacking in his appraisal of the role of Christian creed and dogma in the rise of modern science. Of course, against the dark background produced, propagated, and imposed as a dogma since Francis Bacon and Condorcet agreed — for distinctly different reasons

— that Catholicism in particular and Christianity in general were sworn enemies of learning and science,⁸⁰ any rejoicing over the medieval contribution to the rise of science could but appear in established circles an immoderate overreach, nay a sheer sacrilege, not to be tolerated.

Silence, as will be seen, has been one favorite weapon in this respect. Another has been the labeling of Duhem’s interest in history as a thinly disguised apologetics to which scholarship is subordinate. There is no trace in Duhem’s writings of such motivation whatsoever. His overriding interest was the completeness of the image of physical science. Nothing was, of course, more natural for him than to realize the broader significance of the emergence of science during the Middle Ages in virtue of Christian thought. Such a truth struck at the root of scientism, the unofficial ideology of the Third Republic, In the opening decade of this century, no less than today, the gullible public, including its academic sector, readily swallowed any claim, however unrelated to science and however unfounded, if offered in scientific wrapping. Dismissal of Christianity as an enemy of science and reason is still a chief strategy of her opponents, violent and polite. Only in this light will appear the true physiognomy of the resentment which in certain circles is still provoked by the rejoicing of Duhem, the historian of science, who neither mixed his Catholicism into his historical research, nor was ever ashamed of it. At any rate, unlike many modern historians who try to hide their agnosticism, if not their militantly anti-christian outlook, under the cloak of ‘scholarly objectivity’ free of metaphysical presuppositions, Duhem was here too sincerity itself. Indeed, a Christian sincerity was needed that the fight of the Sorbonne during the 14th century on

79. A claim of E. Rosen, ‘Renaissance Science as Seen by Burckhardt and His Successors, in T. Helton (ed.), The Renaissance: A Reconsideration of the Theories and Interpretations of the Age (Madison: University of Wisconsin Press, 1961), p. 96, based on two rather transparent tactics. One is Rosen’s keeping his readers in the dark about the fact that at most three years separate the publication of the third volume of the Leonardo studies from Duhem’s writing of what became the tenth volume of the Sysr~nme du monde. The second is Rosen’s implicit suggestion that Duhem, who died at the age of 55, was not mature yet as a historian at the age of 52, after ten years of monumental and pioneering researches. More on the motivations of such tactics later; see also note 87 below.

80. For details, see ny The Origin of Science and the Science of its Origin, pp. 7-12 (on Bacon) and pp. 36-39 (on Condorcet).

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The proposition may have appeared daring to many though not to Duhem whose ‘sole concern’ in the matter was ‘to see the Kingdom of God re-established among us’ and who held that he dealt with an ‘objective on behalf of which there was no daring which would not only be permissible but very much in order.’

Nothing would be more misleading about Duhem than this letter if read either with the sanguine eyes of a facile Christian apologist or with the resentful mind of someone bent on keeping science harnessed in the service of unscientific aims. None of Duhem’s writings comes even remotely close to apologetical (or counterapologetical) writings, a genre very much in vogue at that time. At College Stanislas, at the Ecole Normale, and in Lille, Duhem, as was already noted, stood apart from such involvements. He worked out a philosophy of physics to satisfy himself as a physicist. That such a philosophy could be useful for countering the claims of scientism was not something that motivated his work. For years he accepted with no discomfort the standard view of the history of science according to which there was nothing between the Greeks and Descartes. Not in the slightest did he espouse, as he wrote his Evolution of mechanics and the first installments of his Origines de la statique, anything of inept apologetic efforts which in the second half of the nineteenth century tried to rehabilitate scientifically the Middle Ages.⁸⁶ Only rank prejudice would see in Duhem’s celebrated series of essays, To Save the Phenomena, a work motivated by the desire to undercut once and for all the anti-Catholic exploitation of the Galileo case. Duhem’s interest in the motto, ‘to save the phenomena,’ was born out of his wrestling, while in Lille, with the nature of physical theory as an explanation. It was most natural for him to become interested in the whole history of that motto after it had become very clear to him, following his encounter with the writings of Jordanus Nemorarius and with the complex history of Leonardo the scientist, that large segments of scientific history were missing in the standard accounts.

To restore the completeness of the record was enough of a motivation for Duhem to write that famous essay. Historical completeness was a test of the truth of his theory of physics. Since it was the essence of physical science to be mathematical, the truth of physical theory, Duhem noted,⁸⁷ could not be illustrated from medieval physics which for all its insights remained essentially qualitative, even its science of weights, the discovery of which enthralled him so much. Quite different was the case with astronomy. It was the only part of physical science which already in the hands of the Greeks achieved a mature degree of exact, that is, quantitative treatment. In this special status of astronomy Duhem saw a major proof of his

86. The schoolman most often seized upon in that respect was Albert the Great, who was turned into the initiator of the experimental method by F. A. Pouchet, professor of zoology at Rouen, in his Histoire des sciences naturelles au Moyen Age ou Albert le Grand et son e’poque considdre’s comme point de de’part de l’dcole expe’rimentale (Paris: J. B. BailWere, 1853).

87. To Save the Phenomena, 1969 (1), p. 3. This remark of Duhem should suffice to lay bare the hollowness of Rosen’s claim discussed in note 79 above.

402

insight and articulation should seem all the more impressive and daring. Duhem did not wish to win particular battles. His strategy aimed at the entire dispute between formalists and realists and therefore had to cover the field as completely as possible. Canvassing the story from Plato to Copernicus issued in the ten volumes of the Syst~’me du monde and seems to have called for superhuman forces as its almost six thousand pages, bursting with material of astonishing richness, were written in a mere eight years that were not exclusively set apart for the undertaking. Aiming at completeness implied attention to all facets of the process under investigation, and therefore to its slowness, a principal facet if the growth was genuine, that is, organic. Thus Duhem took for the motto of the whole work a dictum of Roger Bacon: ‘Never was any science invented at any particular time, but from the beginning of the world knowledge has grown slowly and is still not complete at this very age.’⁹⁰

Since Duhem’s interest in the history of physical science was a function of his philosophy of physics, it should not be surprising that the Syst~me du monde was from its first volume on a mine of information on the philosophies of those who discoursed on scientific matters from the time of Plato. The first two volumes of the Syst~me dealing with the evolution of cosmology in classical antiquity from Plato to Philoponus would have done credit to a historian of Greek philosophy. The same volumes are still among the best accounts, and in a specific sense the very best account, of cosmological science in Hellenic and Hellenistic antiquity. Duhem’s treatment of the subject was steeped in the belief that all science was a function of a world view. This is why Duhem devoied so much space to the question of tides as discussed by ancient Greek authors.⁹¹ For it was there that came most conspicuously to the fore within a scientific context the intellectually hopeless entanglement of the ancient Greek world view in astrological lore. There the specific sense in which the ancient Greeks attributed unity to the world of things, also came fully to the fore. While the attribution of unity is at least an implicit requirement of any meaningful scientific work, the sense in which such an attribution is made is of decisive importance for the true quality of that work. The unity of all was for the Greeks the unity of a living organism. For them the world was an all-encompassing living entity, a view codified by Plato and Aristotle. Such a world view, in which everything was connected with everything as so many members of one living body, invited Aristotle’s definition of motion that the mover and the moved had to be in continuous contact with one another during the whole duration of motion. Astrological discourse was part and parcel of that organismic view of the world which made the formulation of a correct science of dynamics impossible. Astrological preoccupations, so many threats to human freedom, including the freedom of inquiry, infiltrated and corrupted all scientific discourse

90. Duhem’s admiration for Roger Bacon sharply contrasted with his strictures of Francis Bacon as one who did not understand a thing about the experimental method while singing its

praises (Syst~me du monde, 3:440).

91. Ibid., 2 :266-390.

lost sight of the basic issue. It related to the presence, beneath scientific particulars, of cosmologies which, as he put it, were so many theologies.⁹⁵ The Fathers did not have to be experts on science to oppose and reject those cosmologies and theologies. Yet, by doing so they cleared the ground for a better science and also provided the spark for it. Duhem was not the purist historian afraid of giving a foretaste of the grand conclusion:

Within that perspective it was no rhetoric to lament the demise of classical wisdom in the very lands which saw its birth and development and to recall the coming of new young nations eager to seize the last and almost dry seeds of that wisdom. Much more was at issue than to bring fresh forces to lands peopled by decadent nations where the power of invention was growing feeble. The soil itself, Duhem warned, had to be reworked to let a new vegetation arise.⁹⁷

Apart from this view in depth the Syst~me du monde may appear useful only as a storehouse of data to satisfy the precepts of logical positivism according to which everything meaningful must be ‘on the surface.’⁹⁸ Of course, the Syst~me was bursting with such data. In addition to the long section on tides, its first two volumes are still a first-rate source on each and every discourse of the Greeks of old on homocentric spheres, on heliocentrism, on eccentrics and epicycles, and on the dimensions of the world. The subsequent volumes are bursting no less with ‘positive’ information. The third volume is a still unsurpassed documentation on such a ‘positive’ topic as the medieval reflections on Heraclides of Pontus’ system of the world, a transition between geocentrism and heliocentrism. Duhem did not exaggerate in introducing that third volume with the remark: ‘The desire to learn was intense among the young nations which invaded the Roman Empire.’⁹⁹

98. As stated in the Manifesto of the Vienna Circle. See Wissenschaftliche Weltauffassung:

Der Wiener Kreis (Vienna: Verein Ernst Mach 1929), p. 15.

99.Syst~me du monde, 3:3.

406

to the primacy of common sense notwithstanding. This is well attested by the fifth volume of the Syst~me, which completes Duhem’s treatment of the growing tide of Aristotelianism during the 14th century. He brings it to a close with Siger of Brabant’s espousal of Aristotle. In Duhem’s rendering, Siger’s stance was an unintended warning that Peripatetic doctrine and Christian faith were irreconcilable. Duhem took the 1277 decision as a heeding of that warning. Christendom had to choose, and Duhem was obviously rejoicing over the choice made on behalf of faith against an unreconstructed Aristotelianism. That these were the real alternatives seemed to Duhem exemplified in Siger of Brabant’s insistence that Aristotelianism demanded from Scholastic Christianity, unwilling to reject Catholic orthodoxy, the admission that two contradictory doctrines could both be true:

‘One because the Church taught it, the other because it was rationally demonstrated by the philosophers.’ But Duhem himself cast the alternative also in a form which he hardly thought over: ‘Christianity was expected to sacrifice either its faith or its common sense. The side was quickly taken by Christianity which sacrificed pagan philosophy.’¹⁰² Duhem, a professed apostle of common sense and a convinced Catholic, can hardly be pictured as one relinquishing common sense to a philosophy which he held, in its fully rigorous form, to be an intrinsically pagan philosophy. But his apparent identification of common sense and pagan philosophy lays bare once more the pitfalls of his neglect to articulate the very foundations of his philosophy, a philosophy steeped in the validity of common sense and the metaphysics it invites. Not only the understanding of Duhem’s philosophy was compromised by that neglect but also Duhem’s understanding of medieval science and also his readers’ understanding of what he said. This is however to anticipate.

Reaction to Duhem’s major publications in the history of science was not at all commensurate with the vastness of new material he submitted and to the revolutionary character of his interpretation of it. Curiously, the Origines de la statique was not reviewed in the Revue des questions scientifiques where it first appeared in installments. This was all the more surprising because Paul Mansion, professor of mathematics at the University of Ghent and a first-rate historian of mathematics, was a chief power behind the Revue and had acknowledged in a letter of June 10, 1910, to Duhem, that those installments greatly enhanced the reputation of the Revue abroad. Certainly more was in order if Duhem’s treatment there of Leonardo prompted Charles Ravaisson-Mollien, the foremost Leonardo scholar in France, to send Duhem the following letter on November 27, 1905:

‘I have not read anything more instructive, more interesting, and more original on the character of Leonardo da Vinci and on the proper part which must be attributed to him in that science [of mechanics] - . . This is what you have shown, Monsieur, in a superior manner, in a spirit of perfect equity and this is for me a

108. L. Liard L ‘Universite’ de Paris (Paris: Librairie Renouard — H. Laurens, Editeur: 1909),

410

120. Ibid ., p. 530.

122. Ibid., 17 (1915):463-64.

412

that of our keen grief, would be superfluous.’¹²⁴

124. A. Favaro, ‘L6onard de Vinci a-t-il excerc~ one influence sur Galil6e et son 6cole?’

Italian tradition, a defense n~ less suspect of that chauvinism of which Duhem was charged

time and again, was echoed by other Italian scholars, such as Marcolongo (see his obituary of

Duhem quoted in Ch. 8). They invariably referred to the works of Caverni and of G. Valiati

(1863-1909). Duhem was one of the sponsors of the edition of Valiati’s collected papers,

126. Ibid ., p. 27.

127. Ibid ., p. 28

128. Ibid.

414

Some puzzlement may be in order when one considers surveys of medieval history which earned considerable repute and whose authors had the expertise of historians. Neither science nor Duhem can be found in the medieval volume, published in 1926, of the famed ‘Legacy’ series.¹³⁵ Science fared very poorly and

with no mention of Duhem in the first volume of H. A. L. Fisher’s History of Europe (1935) dealing with ancient and medieval times.¹³⁶ Vituperation was the tone of the ten pages devoted to science in the portrayal of medieval English panorama by G. C. Coulton.¹³⁷ While the two decades which by then had elapsed since Duhem’s death were more than enough to let his findings trickle down to the niveau of high level popularization, they were obviously more than enough to provide scholarly veneer to silence about those findings. Such a silence would not have found much challenge even if historians in basic sympathy with Duhem’s findings had done their best to keep them in focus. Christopher Dawson, with his short though emphatic references to the importance of Duhem’s work,^t38 was one of these historians. Another was H. Butterfield, who, however, was rather off the mark in claiming in 1949 that ‘the work of Duhem . . . has been an important factor in the great change which has taken place in the attitude of historians of science to the Middle Ages.’ 139

135. G. C. Crump & E. F. Jacob (eds.), The Legacy of the MiddleAges (Oxford;Clarendon Press, 1926, and many subsequent reprints). The omission of a chapter on science should seem all the more glaring, because such a chapter was a part of other volumes in the series dealing with the legacy of India, Egypt, Greece, China, and even of the Roman Empire.

Eyre & Spottiswoode, 1935); see especially chs. xx and xxiv on intellectual and monastic

movements and the Catholic mind.

137. Not even Grosseteste is mentioned in the section on science (pp. 43343) in Coulton’s Medieval Panorama: The English Scene from Conquest to Reformation (Cambridge: University Press, 1938). A full generation later only two pages were allotted to science in J. Dahmus’ The Middle Ages: a Popular History (London: Victor Gollaner 1969). Buridan, Oresme, and Duhem are not to be found in The Penguin Book of the Middle Ages (1971), nor in its longer form, The Horizon Book of the Middle Ages (New York: American Heritage Company, 1968). The same is true of The Rise of Christian Europe (New York: Harcourt, Brace & World, 1965), a widely used textbook by H. Trevor-Roper, who deplores the lack of continuation of the I 2th-century scientific renaissance in Chartres! Lack of attention to the intellectual side of the century of Buridan and Oresme is almost total in A Distant Mirror: The Calamitous 14th Century (New York: Alfred A. Knopf, 1971) by Barbara A. Tuchman. Christianity has nothing to do with science in P. Johnson’s much publicized A History of Christianity (1976; Pelican Books, 1980). Many other examples could be quoted.

138. See his Progress and Religion (London: Sheed and Ward, 1929), p. 143; Religion and Other Essay (New York: Sheed and Ward, 1934), pp. 91-92;Religion and the Rise of Western

Culture (London: Sheed and Ward, 1950), p. 16.

139. H. Butterfield, The Origins of Modern Science 1300-1800 (1949; new ed.; London G. Bell & Sons, 1957), p. 15. In making that optimistic generalization Butterfield must have ignored, say, a Charles Singer, in whose A Short History of Science to the Nineteenth Century (Oxford: Clarendon Press, 1941) the Middle Ages, to say nothing of Buridan and Oresme, did not exist at all. A mere look in that book at p. 161 should make one wonder as to what could pass for unquestionable scholarship in the subject with a prestigious academic publishing house.

420

ger’s doctoral thesis)⁶² The author of that article, B. Ginzburg, was also a graduate student at Columbia University and the tone of his article anticipated the air of superiority which set the tone of Lowinger’s thesis, a tone which is usually tolerated by mentors and editors who are driven by that ‘deep-seated apologetical bias’ of which Ginzburg charged Duhem at the very outset of his article. What Ginzburg did not spell out at the outset, although it could easily be guessed, was that enormously far-reaching revisions were in order if ‘the evidence adduced by Duhem [on behalf of the medieval origin of modern science] really stands up,’ because ‘then indeed we must revise our customary ideas on the history and development of modern science.’ 163 Those ideas were indeed more than customary. They were the chief support of Condorcet’s vision of intellectual history and of all the Weltanschauung it implied. Adepts of that vision have for some time taken to the custom of not mentioning it, perhaps because it has already become a tacit foundation of established intellectual discourse, allegedly steeped in sheer objectivity.

Enforcing at least a style, which was not a patent violation of at least a semblance of objectivity, would have of course been the duty of the editor of Isis on reading a graduate student’s manuscript which not only charged a towering scholar like Duhem with ‘deep-seated apologetic bias’ but in which, at the very outset, a wholesale doubt was cast on Duhem the historian: ‘all his findings must be scrutinized with the same suspicion as a lawyer’s brief for a client.’ 164 Ginzburg’s condescending and caustic style should have been bluepenciled by Sarton even if Ginzburg had demonstrated his specific claim that Duhem read into the writings of Jordanus Nemorarius crucial notions which were not there and that ‘any scientifically informed person’ could easily notice Duhem’s confusion about the meaning of Torricelli’s principle. To imply that Duhem was not ‘scientifically informed,’ was already a suggestion unworthy of any scholarly journal, to say nothing of other remarks of Ginzburg: ‘It is easy to show,’ Ginzburg claimed, that ‘much of the evidence Duhem adduces in support of his thesis is palpably false and far-fetched.’¹⁶⁵ Ginzburg spoke of the ‘abstruse nature of Duhem’s theories,’ and of Duhem’s association of Albert of Saxony with the scientific development of statics as ‘completely forced~’ 166 According to Ginzburg there was ‘an element of comedy’ 167 in Duhem’s speaking first of Jordanus Nemorarius alone, then later of him and of his hypothetical disciple. Duhem, according to Ginzburg, was so little a scholar as to cavort in rank arbitrariness: ‘In short, he makes the rule of relative weight operate when he wants it to operate and not operate when he does not want it to operate.’¹⁶⁸ Duhem was also ridiculously

162. Discussed in the preceding Chapter.

163. B. Ginzburg, ‘Duhem and Jordanus Nemorarius,’ Isis 25 (1936) :341 62.

165. Ibid. Ginzburg’s secondary claim was that since there was no second Jordanus, Duhem’s theory of continuity lacked foundation.

167. Ibid., p. 344. ‘Scarcely reasonable’ was in Ginzburg’s view Duhem’s vision of a succession of medievals well versed in what was available on the science of mechanics (p. 351).

168. Ibid., p.350.

173. The Renaissance in Historical Thought: Four Centuries of Interpretation (Cambridge,

last few decades of that half a millennium seemed to have produced a real challenge to the hallowed idea of the Renaissance as the rise of human genius from the shackles of Christianity. It is difficult not to sense that in Ferguson’s view challenges based on philosophy, ethics, sociology, arts, and letters could be coped with. He indeed felt so secure as to write in connection with the Neo-Thomist thesis on the Middle Ages as articulated by Maritain and Gilson, that ‘full acceptance [of them] is difficult if not impossible for non-Catholics.’ 174 Its converse, or the impossibility of the acceptance by Catholics of the ‘established’ thesis, carried no weight in Ferguson’s eyes. Such brazen lack of impartiality, apparently acceptable in reference to philosophy, was obviously inappropriate when it came to science, namely, to the challenge to the Renaissance by historians of medieval science, above all Duhem, ‘the great pioneer.’ The only thing Ferguson could do with that ‘impressive monument’ of scholarship, the five volumes of the Syst~me du monde, was to undermine its significance with the remark ‘that there is a distinct note of patriotic as well as sectarian pride in Duhem’s account.’ 175 Ferguson did not explain why a Haskins and a Thorndike, neither French nor Catholic, to whom after Duhem medieval studies of science owed most prior to 1940, agreed in substance with Duhem’s findings and even with his vision.

Ferguson might have found support in an article published by J. H. Randall Jr. on ‘The Development of Scientific Method in the School of Padua,’¹⁷⁶ in which much was made of the ‘freethinking and anticlerical’ 15th-century Paduan scholars in whom Randall found a pivotal link in the pre-Galilean history of science. The link was a proof of continuity and Randall chastised Galileo, Descartes, and others for not having seen ‘the countless bonds’ which tied them to the medievals

‘in materials, methods and even achievements.’ 177 Yet, the nature of the link, freethinking and anticlericalism, was such as to save the Renaissance as a vision even if it was true that Galileo’s science was ‘the culmination of the cooperative efforts of ten generations of scientists’ that preceded him.¹⁷⁸ Ferguson would have been helped even by D. B. Durand’s ‘Nicole Oresme and the Medieval Origins of Modern Science,’ published in 1941 · t79 Durand, who grudgingly acknowledged Duhem’s pioneering greatness, tried to find a middle road between those who like Duhem saw precursors and his debunkers who would not see any of them. Durand’s was an instructive try inasmuch as it forecast the failure of future efforts to resolve the problem of ‘continuity issuing in novelty’ in the absence of a genuine middle road between conceptual classification (Ideengeschichte) and sociological moulds, both of which Durand rejected. Yet, his solution was only a variation on conceptual classification. He urged that side by side with the notion of genius, at

178. Ibid., p. 177.

179.Speculum 16 (1941):167-85;see especially pp. 172 and 184.

424

Such a message could hardly be welcome for many from a scholar whose expertise in medieval science has often been equated with that of Duhem and who, unlike Duhem, could not be charged with ‘the animus of a Catholic.’ The best one could do with that message was to ignore it. Thorndike’s work, hardly less massive than Duhem’s, was never dignified to any appreciable comment by Koyr~ whose thinking allowed no resolution to the problem noted by Durand. This was made all too clear to the readers of the Journal, most of them still unfamiliar in 1943 with the Etudes, in the last issue of the Journal for the same year:

Those familiar with the capital importance attached by Duhem to common sense

were not at all surprised then to hear Koyr~ continue:

The supreme illusion was, however, the hope of historians of science stepping in Koyr~’s footsteps that it was possible to profit from their field’s ‘exciting interest’ opened up by the master¹⁸⁵ and remain reticent about the nature of truly human cognition and the metaphysics it involves. Their reticence trapped them time and again in the confusion and contradiction unwittingly spelled out in the Etudes. For the author of the Etudes, an advocate of a most unnatural idea of human cognition, which tries to understand man in terms in which some men try to understand animals,¹⁸⁶ could not deny his own human nature calling for common sense. On the surface Duhem, the historian, was the chief target of the Etudes. This would have become crystal clear from the outset had the Etudes appeared with a name index, where Duhem would have figured with over forty entries, far more than any modern scholar mentioned by Koyr~. This would have alerted at least the more perspicacious readers of the Etudes that its real aim was the discrediting of Duhem’s vision. Hardly commendable was Koyr&s tactic which gave only four mentions of Duhem in the text, although no one else stated so forcefully and extensively the thesis of continuity which Koyr~ fiercely opposed

185. C. C. Gillespie, ‘Koyr~, Alexandre,’ Dictionary of Scientific Biography, 7:486.

186. In Koyr6’s Etudes galildennes (1939; Paris: Hermann, 1966) a biological (Darwinian) view of knowledge was, of course, merely hinted, though tellingly, at the very start, through the borrowing of Bachelard’s view of scientific history as a sequence of intellectual mutations. On the unfolding by Koyr6’s disciples of the inner logic of such a start, see ch. 14 ‘Paradigms or Paradigm,’ in my Gifford Lectures, The Road of Science and the Ways to God (Chicago:

University of Chicago i~ress, 1978).

by disregard for logic. It asserted itself in the measure in which a historiography of science steeped in mutations and revolutions, with meanings stretched beyond recognition, gained further converts. As their number grew, not only was there a drop in references to Duhem but also such an increase in the number of revolutions and mutations as to leave hardly a place for normalcy and permanence. Duhem’s memory was not, of course, entirely exorcized either by Koyr~ or by those who did their best to restore credibility to the hallowed sleight-of-hand which starts everything with Galileo. Unlike Duhem, they hardly ever declared their vision or Weltanschauung, although they revealed enough of its driving force. Their prolific discourse obviated the precept according to which silence is the only way to avoid appearing a metaphysician. More ‘positively,’ early euphoria about Koyr~ made no room for suspicion about the nature of logic which forced Koyr~ to dispute any real role for a real inclined plane in Galileo’s mental development. To lay bare the hollowness of that logic required in the end only a graduate student’s resolve to construct a plane along the specifications of Calileo, and let balls roll down on it.¹⁹³ Others could easily watch Koyr~’s brand of Platonism go up in smoke with all its revolutions and mutations.

Duhem fared far better with those students of medieval science who carried on with their work free of prejudices about the question of the origin of modern science, although not unaware of its importance. Theirs was essentially an appreciation of the vast domains opened up by Duhem for study. In the 1920s the most significant of such studies came from the pen of K. Michalski, of the University of Cracow, who reported on the contents of a large number of 14th-century manuscripts in Cracow, Oxford, and the Vatican, manuscripts unavailable to Duhem, In the fourth and last of his major communications, which dealt with the physics of the century of Buridan, Oresme, and Albert of Saxony, Michalski reported a finding which added to Duhem’s conclusions the kind of major corrective that only enhanced his pioneering genius and the solidity of his major message. The finding showed that Buridan, whatever his Ockhamist inspiration, was preceded in the advocacy of impetus theory by the realist school of which Francesco de Marchia was in 1320 a late representative.¹⁹⁴ The intrinsic significance of this finding relates to the scientific potentiality of the realist or Thomist strain of medieval philosophy. Its extrinsic significance emerges in relation to the researches of Anneliese Maier whose work, already begun in the early 1930s, made its impact only after the War and who is often spoken of as the discoverer of Francesco de Marchia as a spokesman of the impetus theory. The revisions Maier felt necessary to add to Duhem’s main conclusions were not essential. ‘Duhem

193. T. B. Settle, ‘An Experiment in the History of Science,’ Science 133 (1961):19-23.

194. K. Michalski, ‘La physique nouvelle et les diff~rents courants phiosophiques au XIVe si’ecle,’ Bulletin international de l’Academie polonaise des sciences et des lettres. Classe d’histoire et de philosophie et de philologie. Annde 1927, pp. ⁹³-t64;on Francesco da Marchia, see p. 158.

publication in a decade,¹⁹⁹ the other forced him to admit that there were several legitimate ways of presenting pre-Galilean science.²⁰⁰ Duhem the historian would not have asked more from his foremost antagonist in the form of a surrender.

Meanwhile the manuscripts of the last five volumes of Duhem’s Syst~me du monde began to be typeset at long last. With the sixth volume published in 1954, his magnum opus entered its fourth part, a portrayal of the impact of the condemnation of 216 theses on March 7, 1277, a date which, as Duhem asserted, was the birth of modern science. ‘One of the major aims of this work,’ he added, was to substantiate this assertion.’²⁰¹ The date was a watershed. Before it the tide of Aristotelianism was coming in, beyond it a reflux became increasingly noticeable. Pursuing the development through the philosophical and theological writings of Henri of Ghent, the German Dominicans, Duns Scotus, Raymundus Lullus, Jean Jandun, Ockham, and Buridan, Duhem felt entitled to conclude after some 700 pages bursting with data and texts:

The seventh volume dealt with the Syst~me’s fifth part or the Parisian physics. Far from being a quick work, the new physics, Duhem warned, was a slow development and yet issued in a novelty which those who worked on it did not foresee. Duhem handled the problem of continuity and novelty with graphic force:

199. See A. Koyal, Etudes d’histoire de Ia pensde scientifique (Pads: Presses Universitaires de France, 1966), p. 49, in reference to Crombie’s Robert Grosseteste and the Origins of Experimental Science 1100-1 700 (Oxford: Clarendon Press, 1953), in which it is argued that the method practiced by Galileo and Newton was fully articulated, at least in its qualitative aspect, in the 13th century (pp. 1 and 9).

200. See Koyr~, ibid., p. 72, in connection with Crombie’s Augustine to Galileo (London:

Falcon Press, 1952), a book which is better known in its second revised edition under the title, Medieval and Early Modern Science (Garden City,NY: Doubleday, 1959). Crumble, who ignores Duhem’s assertions of ontological order, turns him into a conventionalist.

202. Ibid., p. 729.

430

who discoursed about the rotation of the earth. The latter was the culminating point of Volume IX, much of which is taken up by the 14th-century discussions of the tides. The significance which Duhem accorded to those discussions shows him once more the very opposite to that ‘overenthusiastic’ medievalist with farfetched views he is often made out to be:

The issue about which Duhem is most often mentioned, disputed, and maligned is, of course, the rotation of the earth as discussed by Oresme. Duhem, as is now well known, had access only to a rather faulty and incomplete text of Oresme ‘s commentary to Aristotle’s On the Heavens. When Duhem first published in 1909 the famed section from Oresme’s commentary, his comments to it did not go beyond the suggestion that Copernicus may very well have been influenced by Oresme’s detailed consideration of the earth’s rotation as a hypothesis.²⁰⁹ In reinserting the same section in full in Volume IX, Duhem analyzed its meaning at length and he did so in a sense which would have needed no correction had he had access to a better manuscript containing Oresme’s declaration: ‘However, everyone maintains, and I think myself, that the heavens do move and not the earth.’²¹⁰ For, as Duhem noted, Oresme and others were faced with the utility of the hypothesis of the earth’s rotation. Not knowing Archimedes’ Sand Reckoner, in which an account given of Aristarchus of Samos postulating an orbital motion too for the earth, they had to find the earth’s rotation wanting in usefulness. While it could cope with the apparent daily rotation of the sphere of stars, it helped not a whit with respect to the principal problem of astronomy, the irregular motion of planets. Last but not least it created enormous problems for dynamics:

210. For that phrase and the description of six manuscripts of Oresme’s commentary, see Nicole Oresme. Le livre du ciel et du monde, edited by A. D. Menut and A. I. Denomy, translated with an intro Suction by A. D. Menut (Madison: University of Wisconsin Press, 1968), pp. 32-36 and 537.

211. Sysalme du monde, 9:539.

212. Ibid., 10:45.

Not that Duhem ever longed to be spoken of as a genius. As a historian who traced so many meanderings and hesitations of scientific advance, he was all too aware of the vast amount of improvement that can be added to any work, however perfect. Mindful of the sharp criticism in store for anyone joining the intellectual arena with novel facts and interpretations, Duhem would not have been upset by remarks which charge him with ‘overenthusiasm,’ ‘extravagant claims,’ and with ‘Duhemisms,’ when such remarks are balanced with references to his ‘gigantic’ work, to the ‘extraordinary freshness’ of his approach, and to the ‘inestimable debt’ which all students of the history of medieval science owe to the great pioneer.²¹⁵ Quite different would have been Duhem’s reaction to reviews in which the

213.RGScPA 30 (1919):321-22.

214. C. Truesdell in his review (Speculum 36 [19611:121) of M. Clagett’s The Science of Mechanics in the Middle Ages (Madison: University of Wiconsin Press, 1961).

215. See M. Clagett’s reviews of Volumes VI-IX of theSyst~medu monde in Isis 49(1958):

359.62 and 53 (1962):251-52. Duhem would be wholly in his right to request that Ciagett’s charge, according to which he had kept quoting out of context and quoted texts only in part, should either be fully documented or not made at all.

than the Middle Ages.’²¹⁸ It was in that age that the view of existence, cosmic and human, as something created, has become a cultural matrix which cannot be exorcised from historical consciousness. No reflection on history can escape that view which represents the most radical contrast to the modern disregard for the createdness of existence and for its inherent purpose.

Unintended depths are therefore lurking beneath pleas such as the one by Fustel de Coulanges, a plea now more than a hundred years old, ‘for a knowledge of the Middle Ages which is accurate and scientific, sincere and non-partisan, as something of primary importance for our society because such knowledge is the best means of putting an end to the senseless yearnings of some, to the hollow utopias of others, and to the hatred of many.’²¹⁹ Such a plea is for scholars respectful of all facts regardless of their provenance and perspective. Concerning the Middle Ages no fact is so towering as the impact exercised by that Christian faith which stands or falls with its very first tenet, the one professing belief in the Father Almighty, Maker of Heaven and Earth, of all things visible and invisible. While the pagan Greeks of old could, in their few references to the idea of a creation ex nihilo, dismiss it with facile scorn,²²⁰ their modern counterparts have no such liberty as long as they want to be scholars as well. Unless this is recognized, debates about the question whether modern science owed its birth to the Middle Ages or to the Renaissance will run out in sheer evasions or in rank acrimony. To face up to the Christian past of the modern world as a past even potentially useful for the rise of that science, which was raised to the status of divinity in the modern post-Christian world, is therefore a task which, more than any other intellectual task, must breed uneasiness.

218. N. D. Fusrel de Coulanges, ‘Dc l’analyse des textes historiques,’ Revue des questions historiques 42 (Jan. 1887):35. This warning should seem particularly relevant when one pages through The Cultural Context of Medieval Learning. Proceedings of the First International Colloquium on Philosophy, Science and Theology in the Middle Ages — September 1973, edited with an introduction by J. E. Murdoch and E. D. S. Murdoch (Dordrecht: D. Reidel, 1975). There it is claimed that the success of properly grasping medieval science ‘demands much more than the constant dipping into theological and ostensibly philosophical sources -

something that Duhem himself had aiready done with considerable expertise’ (p. 16) and that as a Catholic Duhem ‘might be suspected of bias in favor of medieval Churchmen’ (p. 376). One wonders whether the long-standing neglect, nay contempt, of medieval learning on the

part of professedly agnostic historians of science should not make one far more suspicious of a virulent bias at work. More importantly, one need not be a Catholic, as correctly argued in the foregoing context (p. 376), in order to agree with the Thdorie physique. But when one becomes concerned with its foundation, the realism of common sense, is one not driven precisely toward a metaphysical view, the cultivation of which (as Duhem himself pointed out in his famed reply to A. Rey about the physics of a believer) has been largely confined to Catholics and which, in addition, inescapably implies the acceptance of the tenet of creation as again understood mainly by Catholics?

219. N. D. Fustel de Coulanges, ‘L’organisation de la justice dans l’antiquitd et les temps modernes. III. La justice royale au moyen~ge,’RDM94 (1871):538.

220. For details and documentation, see my Cosmos and Creator (Edinburgh: Scottish Academic Press;Chicago: Regnery-Gateway 1980), pp. 73-74.

436

Uncannily Duhemian in its ring, this passage has for its co-author none other than Einstein, a most reluctant discoverer in modern times of the realism of common sense²²³ and of the perspectives — scientific, philosophical, and historical — which it imposes in final analysis. Duhem served those perspectives with insights and efforts worthy of the genius whose inventiveness, to recall a phrase of Goethe, owes much less to unusual talents than to unremitting labor. Not surprisingly, while all too often Duhem’s insights are dismissed as far-fetched, willful, and even fanatical, the magnitude of his work invariably makes such critics uneasy. Yet, rugged positivists or secularist historians as they may be, they can hardly conceal their satisfaction whenever they can appeal to Pierre Duhem’s immense work, undoubtedly the mark of a genius.

222. A. Einstein and L. Infeld, The Evolution of Physics (New York: Simon and Schuster, l⁹³8),p. 152.

223. See ch. 12 on Einstein in my Gifford Lectures, The Road of Science and the Ways to God (Chicago: University of Chicago Press, 1978).