(b. Taganrog, Russia, 29 Au. gust 1892; d. Paris, France, 28 April 1964)
history of science, of philosophy, and of ideas.
Koyré’s work was threefold. First, he exercised a formative influence upon an entire generation of historians of science, and especially in the United States. In France, secondly, where his circle was mainly philosophical, he also initiated the revival of Hegelian studies in the 1930’s and published important studies of other pure philosophers, most notably Spinoza . Thirdly, his essays on Russian thought and philosophical sensibility were important contri. butions to the intellectual history of his native country [4, 11]. A strong vein of philosophical idealism inspired all his writings, which proceeded from the assumption that the object of philosophical reasoning is reality, even when the subject is religious. A remark in the preface to his study of Jacob Boehme might equally well be applied to any of his books:“We believe … that the system of a great philosopher is inexhaustible, like the very reality of which it is an expression, like the master intuition that dominates it.”1
For Koyré was ever a Platonist. Indeed, the best introduction to the unity of view and value inspiring the whole body of his work is his beautiful essay Discovering Plato , published in 1945 in French and English editions in New York, and originally composed in the form of lectures given in Beirut after the fall of France in 1940. Koyré never despaired of European civilization, however Hellenic its appar. ent disintegration. It was always his inner belief that mind might yet prevail. The contemplative tone disarms resistance to the hortatory discourse, which, mingling jest with seriousness in true Platonic style, opens to the reader the implications of philosophy for personality and of personality for politics, those being the themes that invest the dialogues with dramatic tension.
Koyré said little here of Platonism in the develop. ment of science, but the relation of intellect to charac. ter and of personal excellence to civic responsibility that this essay brings out explains his sympathy for the Platonic inspiration that he detected (and in other writings perhaps exaggerated) in the motivations of the founders of modern science, particularly Galileo.
Koyré began his secondary education at Tiflis and completed it at the age of sixteen at Rostov-on-Don. His father, Vladimir, was a prosperous importer of colonial products and successful investor in the Baku oil fields. Husserl was the idol of Koyré’s schooldays, and in 1908 he went to Göttingen, where, besides the master of phenomenology he had come to follow, he also met Hilbert and attended his lectures in higher mathematics, in 1911 he moved on to Paris and the Sorbonne, where he listened to Bergson, Victor Delbos, André Lalande, and Léon Brunschvicg. Although he did not become as familiar with any of his teachers in Paris as he had with Husserl and his family (Frau Husserl had mothered him a bit), he felt at case in the cooler climate of French civilization.
Before the war he had already begun work on a thesis on Saint Anselm under the direction of François Picavet, then teaching at the École Pratique des Hautcs Eludes, in 1914 Koyré, though not yet a citizen, enlisted in the French army and fought in France for two years. Then he transferred his service to a Russian regiment when a call came for volunteers and went back to Russia, where he continued to fight on the southwestern front until the collapse in October 1917. During the civil war that followed, Koyré found himself among opposition groups which can be best compared to resistance forces, fighting against both Reds and Whiles. After a time, he decided to disengage himself from the melee, and, the war being over, he made his way back to Paris. There he was married with great happiness to Dora Rèyber. mann, daughter of an Odessa family. Her sister also married his elder brother. In Paris he resumed a life of scholarship and philosophy, finding to his astonish. ment that the proprietor of the hotel where he had lodged in his student days had faithfully preserved the manuscript of his thesis on Anselm throughout the war.
Always a philosopher in his own sense of pro. fessional identity, Koyré began his career in the study of religious thought, though it was in the history of science that he later did his deepest work. His first books were theological: Essai sur I’idée de Dieu el les preuves de son existence chez Descartes (1922), L’dée de Dieu dans la philosophie de St. Anselme (1923), and La philosophie de Jacob Boehme (1929). Completion of the first qualified him for the diploma of the École Pratique and won him election as chargé de conférences, or lecturer, in that institution, with which he remained associated throughout his life. The work on Anselm, completed earlier, was published later and satisfied the Sor. bonne’s requirements for the university doctorate, a degree elevated into the doctorat d’État by virtue of the Boehme thesis.
Students of Koyré’s later writings on the history of science will recognize characteristic motifs and methods in the analysis he gave these early subjects. The theological tradition that appealed to him was that most highly intellectualized of apologetic strate. gies, the ontological argument for the existence of God. In the versions given both by its originator, Anselm, and by Descartes, mind rather than religious experience made the connection between personal existence apprehended subjectively and external reality, of which the important aspect in this context was God—though it could as easily be nature when Koyré turned his interest to the natural philos. ophers. His central proposition in regard to Descartes was that the philosopher of modernity owed much to medieval predecessors. It is one that would no longer need to be argued. Neither would his more interesting, supporting assertion of the philosophic value of scholastic reasoning, “subtleties” being a word that Koyré never thought pejorative.
To historians of science the most interesting feature of the discussion is the use that Koyré found Descartes making of the concepts of perfection and infinity. In handling the latter, he showed how the mathematician in Descartes had fortified the philopher and invested the ontological argument with a sophistication unattainable by the reasoning of Anselm. Occasional asides presaged the direction in which Koyiré’s own interests would afterwards develop: for example, “we consider that the most notable achievement of Descartes the mathematician was to recognize the continuity of number. In assimilating discrete number to lines and extended magnitudes, he introduced continuity and the infinite into the domain of finite number.”2 In this book, however, Koyré had his attention on the Meditations and on Descartes the theologian and metaphysicist. Only later, in the beautiful and lucid Entretiens sur Descartes , did Koyré handle instead the Discourse on Method, emphasizing that it was the preface to Descartes’s treatises of geometry, optics, and meteorology. Koyré would then no longer have agreed with his own youthful statement to the effect that, although Descartés altered the whole course of philosophy, the history of science would have been little different if he had never lived.3
Indeed, Koyré’s own natural predilections emerge from the contrast in tone between his two major writings on Descartes. The Entretiens is an enthusiastic book, sympathetic and almost affectionate in its treatment of Descartes. Not so the thesis, a little stilted in its quality, wherein the author does not seem quite at ease with his subject. The constraint comes out overtly in passages concerning Dcscartes’s want of candor, but the reader is left with a more general feeling of artificiality about the very enterprise of treating Descartes theologically. Koyré’s having been a candidate in the division of the École Pratique concerned with “sciences réligieuses,” the V e Section, may quite naturally have affected his choice of a subject. What is surprising, however, is that Koyré remained associated with that section throughout a life devoted largely to the history of science, there being no appropriate provision for the latter subject in the academic structures of Paris. It was a circumstance bespeaking both the rigidity of institutions in the French capital and the flexibility of their administra. tors, despite whose generosity Koyré felt some difficulty over his commitments in his later years.
No ambiguities beclouded the simplicity and serenity of Anselm’s. commitments, and though Koyré’s monograph on the founder of the ontological proof of God’s being is less suggestive of his later interests in its thematics than the thesis on Descartes, it is more so in its treatment, specifically on the score of sympathy and penetration of the man through the texts.
Perhaps Koyré’s most characteristic gift as a scholar (it was the manifestation in scholarship of his personal quality) was his ability to enter into the world of his subject and evoke for the reader the way in which things were then seen: in this case, the spiritual and intellectual reality in which Anselm perceived both beatifically and logically the necessity of God’s being; in other instances, Aristotle’s world of physical objects apprehended by common sense and ranged into an orderly philosophy: Jacob Boehme’s tissue of signatures and correspondences between man and nature: the Copernican globes spinning and revolving for the simple and sufficient reason that they are round; Kepler’s vision of numeri. cal form and Pythagorean solidity; Galileo’s abstract reality of quantifiable bodies kinematically related in geometrical space; and finally Newton’s open universe, with consciousness situated in infinite space instead of in the cosmos of ancient Greek philosophy.
It was through meticulous analysis of essential texts, however, and not through general summary or para. phrase that Koyré thus opened spacious implications out of the intellectual constructions of his subjects. He liked to print extensive passages from the text to accompany his analysis in order that the reader might see what he was about. Indeed, his writing adapted the French instructional technique of explication de texte to the highest purposes of scholarship. Most of his later works derived from courses, often from individual lectures, given in the many institutions in France, Egypt, and the United Slates, where he taught regularly or was a guest. In later years his knowledge sometimes made him seem severe to younger scholars unsure of their own. The effect was altogether unintended. Fundamentally his was a deeply humane intellectual temperament, critical in the analytical and never in the denigrating or destruc. tive sense. He wished to bring out the value in the subjects that he studied, not to expose what might be found of hollowness or falsity in them. Easy targets never tempted him. His own self-assurance was thus compatible with the most serious humility, for he subordinated his gifts to enhancing the merits of those who by mind, daring, imagination, and taste. had contributed to civilizing our culture, and who had thereby aroused his admiration.
Such qualities of empathy animated the important studies he made of Hegelian philosophy and of the intellectual culture of nineteenth-century Russia. Neither of those concerns bore directly on the history of science, but perhaps a word may be said. His knowledge of Hegel derived from youthful immersion in Husserl’s phenomenology. In the early 1930’s he thought to convey the interest it held to his circle of philosophical friends in Paris—formed for the most part in the École Normale Supédrieure—to whom it was largely alien, not to say terra incognita. These papers were well received,4and readers whose case is similar may find particularly illuminating his “Note sur la langue et la terminologie hégéliennes.”5 Similarly, the papers in his two volumes on Russian intellectual history developed for a French learned public a subject for which Koyré had special com. petence: the dilemma of Russian writers torn between the necessity for assimilating European culture if their country were to become civilized, and resisting it if Russia were to establish its own national identity [4, 11]. Admirers of Koyré’s writings in the history of science would do well to read the most considerable of those studies, a monograph on Tchaadaev.”6 Although it has nothing to do with their subject, it is one of the finest, most sympathetic and revealing pieces that he wrote.
By contrast, Koyré’s work on the German mystics did have an important if somewhat enigmatic bearing on his historiography of science, for although he was never more earnest than in mediating between this inaccessible tradition and his modern reader’s sensi. bility, his own reaction to it was to turn from theologi. cal subjects back to the scientific interests of his student days at Göttingen. His major doctoral thesis remains the most considerable and reliable study of Boehme, a lucid book on an obscure writer. Koyré also gath. ered into a little book four short pieces on Schwenk. feld, Sebastian Franck, Paracelsus, and Valentin Weigel, Boehme’s most important sources . Its reissue in 1971 coincided with a revival of the occult that the author would have deplored. True, it might be held that Boehme took an interest in the natural world even as did Galileo, Descartes, and Kepler, his contemporaries. Any resemblance is only apparent, however, for Boehme’s sense of nature was altogether symbolic, the reality of phenomena residing for him in the signatures they bear of the divine. It is true that Koyré’s awareness of how the world had impinged on consciousness before modern science destroyed these symbolic meanings sensitized his later writings on the scientific revolution. But he came to feel a certain futility in the enterprise of exploring the experiences of mystics, which by definition could be known only by him to whom they happened, Boehme was consistent in always seeking to read the corre. spondence between man and the world out of what he often called the book of himself, whereas the Koyré of Études galiléennes observed in the opening lines that only the history of science invests the idea of progress with meaning since it records the conquests won by the human mind at grips with reality.7
However that may be, the leitmotif of Koyré’s work in history of science was the problem of motion; and he first identified it in a philosophical essay,“Bemerkungen zu den Zenonischen Paradoxen,”. published in 1922, prior to these theological writings.8 In this, his first substantial publication,9 Koyré argued that understanding Zeno’s puzzles required analysis not merely of motion but of the manner in which its conceptualization in parameters of time and space involved ideas of infinity and continuity. After reviewing the Zenonian contributions of Brochard, Noël, Evelyn, and Bergson, Koyré (no doubt thinking back to his studies with Hilbert) invoked the findings of Bolzano and Cantor on the infinite and the nature of limits, and distinguished between motion as a process involving bodies in their nature and motion as a relation to which they are indifferent in them. selves. A footnote anticipated Koyré’s lifework in a single sentence: “All the disagreement between ancient and modern physics may be reduced to this: whereas for Aristotle, motion is necessarily an action, or more precisely an actualization (actus entis in potentia in quantum est in potentia), it became for Galileo as for Descartes a state.”10 Towards the end of his life, Koyré was sometimes asked how he happened to turn from theology to science, and once said, “I returned to my first love.”11
His own career was full of movement. He had prepared his materials on Russian intellectual history in the first instance for a course at the Institut d’Études Slaves of the University of Paris. In 1929, the year Jacob Boehme appeared, he was appointed to a post in the Faculty of Letters at Montpellier and taught there from September 1930 until December 1931, enjoying the climate and quality of life in the Midi while regretting the inaccessibility of libraries. In January 1932 he was elected a directeur d’études at the École Pratique and returned to Paris, where his course treated of science and faith in the sixteenth century. Having read Copernicus for that purpose, and found how little was really known of his epochal accomplishment, Koyré prepared a translation of book 1 of De revolutionibus, its theoretical and cosmological part, together with a historical and interpretative introduction . It was his initial contribution to history of science proper. In it Copernicus stands forth a thinker about the universe and no mere manipulator of epicycles, a thinker at once archaic and revolutionary. He was archaic in his addiction to the Platonic aesthetic of circularity, making it into a cosmic kinematics. He was revolu. tionary in his conviction that geometric form must comport with physical reality, and that no hypothesis joining the two was too daring to adopt, let the consequences be what they might for tradition and common sense. By implication, form itself became geometric, instead of substantial, and down that road lay modern science.
When Koyré published his Copernicus edition in 1934, he was teaching on a visiting basis at the University of Cairo. Finding his colleagues and students most congenial, he returned there in I936-1937 and again in 1937-1938. For that audience he prepared lectures later developed into the Entretiens stir Descartes. Having turned from Copernicus to Galileo, it was also in Cairo that he settled down with the great Favaro edition of the lalter’s works, a set of which he had brought to Egypt, and there composed his masterpiece, Études galiléennes.12 The title page gives 1939 for the date of publication. Actually it appeared in Paris in April 1940, just prior to the German invasion. Koyré and his wife were once again in Cairo. He wished to serve amid the disasters, and they hurried back to France, reaching Paris just as the city was surrendered. Thereupon they turned about, making their way first to Montpellier, and then by way of Beirut back to Cairo. Koyré had already determined to rally to the Free French and offered his services to De Gaulle when the General came to Cairo. Since Koyré held an American visa, De Gaulle felt that the Free French cause might benefit from the presence in the United States of a man of intellectual prominence able to express the Gaullist point of view in a country where government policy was favorable to Pétain. Somehow, the Koyrés found transportation by way of India, the Pacific crossing, and San Francisco to New York. There he joined a group of French and Belgian scientist, and scholars in creating the École Libre des Hautes Études, and he taught there as well as in the New School for Social Research throughout the war, making one trip to London in 1942 to report to Do Gaulle, in New York he developed the familiar. ity with American life that made it natural for him to spend in his later years something like half of his professional life in the United States.
It was in the United States in the immediate post. war years that Études galiléennes, not much noticed amid the distraction of scholarship by war, found its widest and most enthusiastic public, a case of the right book becoming known at the right time. A new generation of historians of science, the first to conceive of the subject in a fully professional way, was just then finding an opportunity in the expanding Ameri. can university system, which more than made up in flexibility and enthusiasm for science whatever it may have lacked in scholarly sophistication and philo. sophical depth. Casting about through the literature in search of materials, they came upon Études galiléennes as upon a revelation of what exciting intellec. tual interest their newly found subject might hold, a book which was no arid tally of discoveries and obsolete technicalities, nor a sentimental glorification of the wonders of the scientific spirit, nor yet (despite the author’s Platonism) a stalking horse for some philosophical system, whether referring to science like the positivist outlook or to history like the Marxist.
Instead, they found a patient, analytical, and still a tremendously exciting history of the battle of ideas waged by the great protagonists, Galileo and Descartes, in their struggle to win through to the most fundamental concepts of classical physics, formula. tions that later seemed so simple that schoolchildren could learn them with ease and without thought. It was a struggle waged not against religion, nor super. stition, nor ignorance, as the received folklore of science would have it, but against habit, against common sense, against the capacity of the greatest of minds to commit error amid the press of their own commitments. Koyré sometimes observed, indeed, that the history of error is as instructive as that of correct theory, and in some ways more so, for although nothing to be celebrated—he was no irrationalist—it does exhibit the force and nature of the constraints amid which intellect needs must strive in order to create knowledge. (The more strictly philosophical problem of the false was one that he developed intensively in its classical context in a charmingly ironic essay, Epiménide le menteur .)
Koyré’s technique was to study problems both intensively and broadly, intensively for themselves and broadly in the awareness of their widest signifi. cance. Études galiléennes consists of three essays published in separate fascicles. The first is entitled À I’aube de hi science classique, the latter phrase meaning classical physics. The theme that unites all three is the emergence of that science (without which the rest of modern science is unthinkable) from the effort to formulate the law of falling bodies and the law of inertia, the subjects respectively of the second and third fascicles. The subtitle of the first fascicle,“La jeunesse de Galilée,” implies that Galileo’s early education and first researches recapitulated the main stages in the history of physics from its origins in antiquity, Koyré’s sympathetic summary of Aristote. lian physics emphasizes the anomaly of the cause attributed to motion in projectiles and explicates the reasoning of Benedetti and Bonamico, from whom Galileo learned physics and who developed the fourteenth-century impetus theory into a scheme for explaining the flight of missiles and fall of heavy bodies. Only when Galileo abandoned the idea of causal impetus, however, did he begin to lead the way from a physics of quality to a physics of quantity. He first attempted that step in the analysis in his youthful De motu, left in manuscript. There he substituted Archimedean for Aristotelian methods and formulated the relation between a body and its surrounding medium in terms of relative density.
In Koyré’s view, geometrization of physical quan. tity in the Archimedean sense was the crux of the scientific revolution. The intellectual drama, becoming at times a comedy of errors in Études galiléennes, is made to consist of a counterpoint between Galileo and Descartes striving to disengage the law of falling bodies and the law of inertia, respectively the earliest and the most general laws of modern dynamics, from concealment by the gross behavior of ordinary bodies throughout the everyday world. In the end Galileo achieved the law of fall and Descartes the concept of inertia. Galileo began in 1604 in private correspon. dence with a correct statement of the former law—that the distance traversed in free fall from rest is propor. tional to the square of the elapsed time—and simul. taneously attributed it to an erroneous principle—that the velocity acquired at any point is proportional to the distance fallen.
In fact, velocity is proportional to time in constant acceleration, and the irony that reveals the depth of the mistake is that Descartes independently repeated these same confusions fifteen years later in his corre. spondence with Beeckman. The specific trouble lay in the mutual unfamiliarity of mathematics and dynamics. However clearly Galileo saw the need for formulating the latter in terms of the former, his only tools for mathematicizing motion were arithmetic and geometry. Analytical though his mind was, proportion had to do the work of functional inter. dependence, and it was not intuitively clear to him at the outset that lapse of time could naturally be expressed in geometric magnitudes. His instinct having been eminently that of a physicist, Galileo eventually worked through to a resolution of his error. The Discorsi incorporates a fully mathematical deriva. tion of the law from the principle of uniform accelera. tion, followed by the famous experimental verification on the inclined plane (which Koyré in his own excessive skepticism about the experimental compo. nent of early physics dismissed as a thought experiment).
Less fortunate with this problem was Descartes. Committed to identifying physics with geometry, he never did perceive that his formulation of fall was inconsistent with the physical description of the phenomenon. But if this tendency to “géometrisation à outrance” concealed the elements of the physical problem from Descartes, it was on the other hand just such mathematical radicalism that led him to the law of inertia, unconcerned to say where motion would stop and what could hold the world together if bodies tended to move in straight lines to infinity. Before this physical problem, Galileo finally drew back into the traditional conception that on the cosmic scale motion endures in circles, and left it to Descartes to enunciate the more general, the universal law of motion. Attributing the law of inertia to Descartes was certainly one of the most original and surprising of Koyré’s findings in Études galiléennes, and it is central to the argument. In consequence of that principle, the ancient notion of a finite cosmos centered around man and ordered conformably to his purposes disappeared into the comfortless expanse of infinite space. In Koyré’s view, the scientific revolu. tion entailed a more decisive mutation in man’s sense of himself in the world than any intellectual event since the beginnings of civilization in ancient Greece, and it came about because of the change that solving the basic problems of motion required in conceiving their widest boundaries and parameters.
In the postwar years Koyré resumed his post in Paris while lecturing from time to time at Harvard. Yale, Johns Hopkins, Chicago, and the University of Wisconsin. Western Reserve University awarded him its honorary doctorate of L.H.D. in 1964, In 1955 he came to the Institute for Advanced Study in Princeton, where he was appointed to permanent membership in the following year. From then until his health began failing in 1962, he spent six months of the year in Princeton, returning to Paris each spring to give his annual course at the École Pratique. The tranquillity of the Institute, and specifically its Rosenwald collection of first editions in the history of science, were essential to the completion of his further works. He was greatly stimulated and encour. aged in their composition by his association with Harold Cherniss and Erwin Panofsky, and also by the acumen and criticism of Robert Oppenheimer, then the director of the Institute, in whose bracing company Koyré was one of the very few people with the intellectual self-possession to feel at ease.
Those works carry further the main themes that Koyré discerned in the scientific revolution, its history and philosophical aspects. La révolution astronomique was the last book he left in finished form, and consists of a very substantial treatise on Kepler’s transforma. tion of astronomy, preceded by a resume of Koyré’s earlier discussion of Copernicus and followed by an essay on the celestial mechanics of Borelli. This last was one of his most original contributions to the literature, for although Borelli has been well known to scholars for his mechanistic physiology, the intricate rationalities of his world machine had been very little studied in modern times. As for the main part of the book, Kepler was always one of Koyré’s favorite figures, appreciated for his boldness, for his imagina. tion, for his Platonism, finally for his accuracy. Koyré distinguished his touch from that of Copernicus by making him out an astrophysicist needing a physical explanation of the planetary motions, in search of which he came upon his mathematical laws. In no way did Koyré underplay the fantastic and Pythagorean aspects of Kepler’s thought. Indeed, it might be said that Koyré’s earlier interest in German mysticism met his later commitment to science in his study of Kepler. Ultimately, however, we have Kepler making his mark through the fertility of an imagination controlled by fidelity to physical fact.
The themes that interested Koyré reached their dénouement in the Newtonian synthesis, and his essay on its significance is one of the most lucid, serene, and comprehensive of his writings. It opens the volume of Newtonian Studies published after his death. Perhaps it is a pity that he did not see fit to include“A Documentary History of the Problem of Fall From Kepler to Newton”  for that meticulous mono. graph exhibits at his scholarly best his gift for treating the ramifications of a single problem in detail and in generality as they appeared to the succession of analytical minds that handled it. For the rest, Koyré was not given the time to establish the same degree of coherence among his several studies of Newton that he did in Études guliléennes. In the last years of his life, he was collaborating with I. Bernard Cohen on the preparation of a variorum edition of the Principia, currently in press. The essay in Newtonian Studies on “Hypothesis and Experiment in Newton”. translates the famous “hypotheses non fingo” to mean “feign” not “frame,” and takes issue with the attribution of a positivistic philosophy to Newton himself. The most substantial essay in the volume contrasts Newtonian with Cartesian doctrines of space, and carefully explores the theological implica. tions of the difference, a theme worked out more fully in Koyré’s From the Closed World to the Infinite Universe.
Completed earlier than Newtonian Studies, this important work follows the metaphysical course of the transition epitomized in the title, beginning with the cosmology of Nicolas of Cusa and culminating in the Newtonian assertion of the absoluteness of infinite space and the omnipotence of a personal God distinct from nature. Theologically, the critical issue throughout was the relation of God to the world, for it appeared, and most subtly so to Henry More, that Cartesian science escaped atheism only by falling into pantheism. In regard to these issues Koyré’s discus. sion may seem a little bodiless to readers whose sensibilities are less finely attuned to the metaphysical and theological implications of the old ontologies. The problems will come alive, however, if they are transposed from a metaphysical into a psychological key. It is the sort of reading that would be consonant with his own admiration for the writings of Émile Meyerson, to whose memory he dedicated Études galiléennes,13 and that would place From the Closed World alongside that work as its more philosophical complement or companion, concerned with what Koyré now calls “world-feelings”14 in contrast to world views.
The central theme is that of alienation, the alienation of consciousness from nature by its own creation of science. Put in those terms the metaphysical anxieties about God and the world will take on reality in modern eyes, and that is precisely what the destruction of the Greek cosmos entailed:
The substitution for the conception of the world as a finite and well-ordered whole, in which the spatial structure embodied a hierarchy of perfection and value, that of an indefinite and even infinite universe no longer united by natural subordination, but unified only by the identity of its ultimate and basic components and laws. and the replacement of the Aristotelian conception of space—a differentiated set of innerworldly places—by that of Euclidean geometry—an essentially infinite and homogeneous extension—from now on considered as identical with the real space of the world.15
Yet if this emphasis in Koyré might give aid to the current fashion for deploring science as something set against humanity, his treatment gives protagonists of antiscientism no comfort. It is significant that of all the great minds of the seventeenth century, the only one apart from Bacon with whom Koyré felt little sympathy was Pascal [18 q]. For he always held the creations of intelligence to be triumphs in the long battle between mind and disorder, not burdens to be lamented.
1.La philosophie de Jacob Boehme, p. viii.
2.L’idée de Dieu et les preuves de son existence chez Descartes, p. 128..
3.La philosophie de Jacob Boehme, p. vi.
4.Jean Wahl, “Le rôle de A. Koyré dans le developpement deséludes hégéliennes en France,” in Archives, de philosophie, 28 (July-Sept. 1965), 323-336.
5.Études d’histoire tie la pensée philosophique; originally published in Revue philosophique, 112 (1931), 409-439.
6.Études sur l’histoire des idées philosophique, pp. 19-102.
7.Études galiléennes, p. 6.
8.Jahrbuch für Philosophie und phänomenologische Forschung, 5 (1922), 603-628; published in French in [17 a].
10.Éludes d’histoire de la pensée philosophique, p. 30, n. 1.
11.Koyré left among his papers a curriculum vitae of 1951 which sets out his own sense of the interconnectedness of the work that he had accomplished and that he then pro. jected; see Éludes d’histoire de la pensée scientifique, pp, 1-5.
12.Two articles containing parts of the work had already appeared: “Galilée et l’expérience de Pise,” in Annales de l’Université de Paris, 12 (1937), 441-453; “Galilée et Descartes,” in Travaux du IXe Congrés international de Philosophie, 2 (1937), 41-47.
13.f. Koyré’s “Die Philosophic Émile Meyersons,” in Deutsch-Französische Rundschau, 4 (1931), 197-217, and his “Les essais d’Émile Meyerson,” in Journal de psycho. logie normale et pathologique (1946), 124-128.
14.From the Closed World to the Infinite Universe, p. 43.
15.ibid., p. viii.
A Festschrift entitled Mélanges Alexandre Kayré, 2 vols. (Paris, 1964), was organized on the occasion of Koyré’s seventieth birthday. The second volume opens with the list of his principal publications, comprising some seventy-five titles. We limit the present article to identifying his books, together with the more important of his articles, those mentioned in the footnotes above and under items , , and  below, P is a testimonial to the continuing interest in Koyré’s specialized studies that in his later years and after his death, associates and publishers thought it important to collect and reissue these writings in book form. Readers may find it helpful to know the contents of those collections.
 L’idée de Dieu et les preuves de son existence chez Descartes (Paris, 1922; German trans., Bonn, 1923).
 L’idée de Dieu dans la philosophie de S. Anselme (Paris, 1923).
 La philosophie de Jacob Boehme; Étude sur les ari. gines de la métaphysique allemande (Paris, 1929).
 La philosophie et le mouuement national en Russie an début du XIXe siécle (Paris, 1929).
 N. Copernic: Des Revolutions des orbes célestes, liv. 1, introduction, traduction et notes (Paris, 1934; repub.1970).
 Spinoza: De Intellectus Emendatiane, introduction, texte, traduction, notes (Paris, 1936).
 Études galiléennes (Paris, 1939): I, À l’aube de la science classique; II, La loi de la chute des corps, Descartes el Galilée; III, Galilée et la loi d’inertie..
 Entretiens sur Descartes (New York, 1944); repub. with ‘9’ (Paris, 1962).
 Introduction à la lecture de Platon (New York, 1945);English trans.. Discovering Plato (New York, 1945);Spanish trans. (Mexico City, 1946); Italian trans, (Florence, 1956); repub. in combination with ‘8’ (Paris, 1962).
 Epiménide le menteur (Paris, 1947).
 Études sur I’histoire des idées philosophiques en Russie (Paris, 1950).
 Mystiques, spirituels, alchimistes du XVIe siécle allemand: Schwenkfeld, Seb. Franck, Weigel, Paracelse (Paris, 1955; repub. 1971).
 A Documentary History of the Problem of Fall From Kepler to Newton: De motu gravium naturaliterca. dentium in hypothesi terrae motae,” in Transactions of the American Philosophical Society, 45 , pt. 4 (1955), 329-395.A French translation is in press (Vrin) under the title Chute des corps et moivement de la terre dc Kepler à Newton: Histoire et documents du problémes.
 From the Closed World to the Infinite Universe (Baltimore, 1957; repub. New York, 1958); French trans.(Paris, 1961).
 La révolution astronomique: Copernic, Kepler, Borelli (Paris, 1961).
 Newtonian Studies (Cambridge, Mass., 1965);French trans. (Paris, 1966).
 Études d’histoire de la pensée philosophique (Paris, 1961).
(a)“Remarques sur les paradoxes de Z énon” (1922).
(b) “Le vide et l’espace infini au XIVe siècle” (1949).
(c)“Le chien, constellation céleste, et le chien, animal aboyant” (1950).
(e)“Louis de Bonald” (1946).
(f)“Hegel à lena”(l934).
(g)“Note sur la langue et la terminologie hégéliennes” (1934).
(h)“Rapport sur l’état des études hégéliennes en France” (1930).
(i)“De l’influence des conceptions scientifiques sur I’évolution des théories scientifiques” (1955).
(j)“L’évolution philosophique de Martin Heidegger” (1946).
(k)“Les philosophers et la machine” (1948).
(l)“Du monde de l”à-peu-près’ à l’univers de préci. sion “(1948).
 Études d’histoire de la pensée scientifique (Paris, 1966).
(a)“La pensée moderne” (1930).
(b)“Aristotélisme et platonisme dans la philosophic du Moyen Age” (1944).
(c)“L’apport scientifique de la Renaissance” (1951).
(d)“Les origines de la science moderne” (1956).
(e)“Les étapes de la cosmologie scientifique” (1952).
(f)“Léonard de Vinci 500 ans aprés” (1953).
(g)“La dynamique de Nicolo Tartaglia” (I960).
(h)“Jean-Baptiste Benedetti, critique d’Aristote” (1959).
(i)“Galilée et Plalon” (1943).*.
(j)“Galilée et la révolulion scientifique du XVIIe siècle” (1955).*
(k)“Galilée et l’experience de Pise: à propos d’une legende”(l937).
(l)“Le ’De motu gravium’ de Galilée: de l’expérience imaginaire et de son abus” (1960).**
(m) “Traduttore-truditore,’ à propos de Copernic et de Galilée” (1943).
(n)“Une expérience de mesure” (1953).*
(o)“Gassendi et la science de son temps” (1957).**
(p)“Bonaventura Cavalieri et la géométric des continus”(1954).
(q)“Pascal savant” (1956).**
(r)“Perspectives sur l’histoirc des sciences” (1963).
* English original republished in .
** English translation published in .
 Metaphysics and Measurement (London. 1968). English versions of  i, j, l, n, o, and q.
II. Secondary Literature. Accounts of Koyré and his work have appeared as follows: Yvon Belaval, Critique, nos. 207-208 (1964), 675-704; Pierre Costabel and Charles C. Gillispie, Archives Internationales d’histoire des sciences, no. 67 (1964), 149-156; Suzanne Delorme, Paul Vignaux, René Taton, and Pierre Costabel in Revne d’histoire des sciences, 18 (1965), 129-159; T. S. Kuhn, “Alexander Koyré and the History of Science,” in Encounter, 34 (1970), 67-69; René Taton, Revue de synthése, 88 (1967), 7-20.
Charles C. Gillispie
Alexandre Koyré (1892–1964), historian of science, was born in Taganrog, Russia. His family was well-to-do—his father, an industrialist, had interests in the Baku oil fields—and there was no need for Koyre to worry about a career after he had completed his secondary studies in Tiflis and Rostov-on-Don. In 1908 he went to Göttingen, where he remained for three years, taking courses with Husserl and Hilbert; he then went to Paris for another three years of study, especially under Bergson, Picavet, and Léon Brunschvicg. In 1914 he enlisted in the French army. The Russian Revolution destroyed his financial resources, and at the end of the war he had to find a profession. At the école Pratique des Hautes Études, where he had been appointed as instructor, he obtained a diploma, with a thesis entitled Essai sur I’idée de Dieu et les preuves de son existence chez Descartes (1922). He was married in that same year. Later he received a doctoral degree from the University of Paris with a thesis on the philosophy of Jacob Boehme (1929).
After a year as maître de conférence at Montpellier, from 1929 to 1930, Koyré returned to Paris as instructor at the École Pratique des Hautes Études, where he taught until his retirement. In the 1930s he was on several occasions visiting professor in Cairo. During World War II he taught at the New School for Social Research in New York, and after the war at the University of Chicago, Johns Hopkins University, and the University of Wisconsin. In 1956 he was appointed a member of the Institute for Advanced Study at Princeton. He served as director of the Centre de Recherches d’Histoire des Sciences et des Techniques, connected with the École Pratique des Hautes Études, and as permanent secretary of the Académic Internationale d’Histoire des Sciences. He was honored by the Académic des Sciences, the Academic des Sciences Morales et Politiques, the History of Science Society, and the Centre Nationale de la Recherche Scientifique.
From 1933 on, when his first studies in philosophy and religion convinced him of the unity of human thought, Koyré made this conception of unity the guiding principle in his research into scientific thought. It was as a philosopher and scholar that he studied sixteenth-century and seventeenth-century astronomy, mechanics, and mathematics: from Tartaglia to More, from Copernicus to Newton. The date of the appearance of his Etudes galiléennes, 1939, is a crucial one for the history of science.
The following precepts characterize Koyré’s method:
(1) It is important to go back to original texts, as far as possible in their original languages, without converting their terms or their methods into a modern idiom.
(2) Scientific works should be related to their intellectual context, which means (a) a comprehensive scrutiny of the relevant literature, rather than the more or less arbitrary selection of extracts; (b) investigation of the works of minor and unknown writers, as well as of those of the great authors; (c) finding out what the scientists themselves made of their own discoveries and what opinions, however false, their contemporaries had of the value of these discoveries; (d) an appreciation of the originality of a thinker’s contribution, rather than its reduction to an outgrowth of the work of his precursors.
(3) The shifts in an author’s point of view should be followed attentively.
(4) Errors and failures should be studied as carefully as successes, so that the development of thought may be grasped “dans le mouvement meme de son activite creatrice”—in the very process of its creative growth.
(5) Within the basic unity of human thought, scientific thought has a special character, and this should be revealed by focusing study on scientific works, rather than straying into psychological, economic, or other explanations of how they came about.
These theoretical and methodological precepts reflect Koyré’s conception of the history of science, which may be summed up as follows:
(1) The realm of ideas is fundamentally one, and it has priority over other areas of human activity. Experience is secondary, although the positivists have never understood this. Koyré was a Platonist and liked to consider Galileo’s work, for example, as an experimental verification of Platonism.
(2) In Koyré’s Platonic conception of science, and contrary to the Aristotelian view, there is a progressive mathematization of the physical world, “from the world of the approximate to the universe of the exact.”
(3) The progress of thought is orderly, which means both that the world of ideas is timeless and that the creative potential of thought is realized in time.
(4) Thought progresses from confusion to clarity by virtue of errors that are overcome. As Kepler had admonished: “Know then that it is errors that show us the road to truth.”
Koyré’s influence was delayed but has been in-creasing. In France, scholars at the Centre de Recherche d’Histoire des Sciences et des Techniques—Pierre Costabel, René Taton, F. Russo— have been carrying on his work; in the United States, the generation of historians of science whose careers began just before or during World War II—Marshall Clagett, I. Bernard Cohen, Charles C. Gillispie, Henry Guerlac, John Murdoch —owes a debt to Koyré.
1922 Essai sur Vidée de Dieu et les preuves de son existence chez Descartes. Paris: Leroux.
1929 La philosophic de Jacob Boehme. Paris: Vrin.
1938 Trois lecons sur Descartes. Cairo, Université Égyptienne, Faculté des Lettres, Publications, No. 20. Cairo: Imprimerie Nationale.
1939 Études galileennes. Actualités scientifiques et industrielles, Nos. 852, 853, and 854. 3 vols. in 1. Paris: Hermann. → Volume 1: A l’aube de la science classique. Volume 2:La loi de la chute des corps: Descartes et Galilée. Volume 3: Galilée et la loi d’inertie.
1953 An Experiment in Measurement. American Philosophical Society, Philadelphia, Proceedings 97:222–237.
1955 A Documentary History of the Problem of Fall From Kepler to Newton: De Motu Gravium Naturaliter Cadentium in Hypothesi Terrae Motae. American Philosophical Society, Transactions, N.S. Volume 45, part 4. Philadelphia: The Society.
1957 From the Closed World to the Infinite Universe. Baltimore: Johns Hopkins Press.
1961 La révolution astronomique: Copernic, Kepler, Borelli. Paris: Hermann.
1962 Études d’histoire de la pensée philosophique. Paris: Colin.
Newtonian Studies. Cambridge, Mass.: Harvard Univ. Press, 1965—.
Belaval, Yvon 1964 Les recherches philosophiques d’Alexandre Koyré. Critique 20:675–704.
Cohen, I. Bernard; and Taton, Rene 1964 Hommage á Alexandre Koyré. Preface in Mélanges Alexandre Koyré publiés a I’occasion de son 70e anniversaire. Volume 1: L’aventure de la science. Paris: Hermann.
Costabel, Pierre; and Gillispie, Charles C. 1964 In Memoriam: Alexandre Koyré (1892–1964). Archives internationales d’histoire des sciences 17, no. 67:149–156.
Herivel, J. 1965 Alexandre Koyré [Obituary]. British Journal for the History of Science 2:257–259.
Mélanges Alexandre Koyré publiés á l’occasion de son 70e anniversaire. 2 vols. 1964 Paris: Hermann.
Russo, F. 1965 Alexandre Koyré et 1’histoire de la pensée scientifique. Archives de philosophie 23, no. 3:337–361.