Discours de la Methode pour bien conduire sa Raison, & chercher la Verité dans les Sciences. Plus la Dioptrique, les Meteores, et la Geometrie. Qui sont des essais de cete Methode.
Leiden: Jan Maire, 1637. First edition of Descartes’s first and most famous work, published anonymously by Jan Maire at Leiden on 8 June 1637 — the Lessing J. Rosenwald–Richard Green copy. The volume contains four texts: the Discours de la méthode pour bien conduire sa raison, et chercher la verité dans les sciences, now celebrated as one of the foundational works of Western philosophy; and three Essais offered as demonstrations of the method — La Dioptrique, Les Météores, and La Géométrie. The third of the Essais, La Géométrie, contains the invention of analytic or coordinate geometry: the identification of algebraic equations with geometric curves that made the later achievements of seventeenth-century mathematical physics — the calculus of Leibniz and Newton, the celestial mechanics of the Principia, the analysis of Euler — technically possible. John Stuart Mill called it the greatest single step ever made in the progress of the exact sciences. The circumstances of the book’s composition and publication are inseparable from its content. In October 1629 Descartes had begun work on a comprehensive natural philosophy, Le Monde, which incorporated the theories of light, perception, and meteorology that would later become the first two Essais, together with a cosmogony in which the formation of the earth and the planets was explained mechanistically and without recourse to Scripture. By 1633 the book was nearly finished. Then, in November of that year, Descartes learned that Galileo had been condemned by the Roman Inquisition for defending heliocentrism in the Dialogo. Le Monde contained the same doctrine — a moving earth in a vortex of subtle matter orbiting the sun. Descartes suppressed the work immediately. He wrote to Mersenne that he would rather suppress his physics entirely than publish it mutilated, and that he hoped the Roman decision would be reversed in time for him to release the book intact. It was not. Le Monde was not published until 1664, fourteen years after Descartes’s death, and then only in fragmentary form. For the next four years he considered how to release to the public those portions of his physics that were not theologically dangerous. The solution was the volume of 1637: three scientific essays whose conclusions derived from the suppressed foundations, introduced by a prefatory Discours that outlined the method by which the conclusions had been reached without stating the metaphysical and physical premises on which they rested. The Discours de la méthode, in other words, is a preface to a book from which the foundations have been deliberately withheld — an act of philosophical engineering whose structure is determined by the Galileo affair as directly as any scientific text of the century. Descartes wrote in French, not Latin. The decision was deliberate and provocative. Latin was the universal language of European scholarship and the medium in which every serious philosophical work since the Middle Ages had been composed; by writing in the vernacular Descartes was dissociating his work from the scholastic Aristotelianism it attacked and directing it toward an audience of educated readers — explicitly including women — who had not been formed by university training. The relative openness of women to new ideas, uncorrupted by the schoolroom authority Descartes was dismantling, later became a central argument in the Cartesian case for women’s education. Publication was anonymous: the French privilege, obtained only after protracted negotiation through Mersenne and Constantijn Huygens, named neither author nor title, and the printer Jan Maire set the last folio without identifying the writer. The Discours itself — seventy-eight pages in the original printing — summarises in six parts a philosophy that Descartes was not yet prepared to present in full. Part I is an intellectual autobiography: Descartes describes his education at La Flèche, his disenchantment with received learning, and his decision to seek knowledge not in books but in the world and in the operations of his own reason. Part II sets out the four rules of the method — to accept nothing as true that is not clearly and distinctly known to be so; to divide difficulties into as many parts as possible; to proceed from the simplest objects to the most complex; and to make enumerations so complete that nothing is omitted. Part III offers a provisional morality for the period during which the old philosophy is being demolished and the new one not yet built. Part IV arrives at the proposition on which everything else will rest: je pense, donc je suis — I think, therefore I am — the one certainty that survives the radical doubt of all received knowledge, and the foundation from which Descartes reconstructs the existence of God, the reliability of clear and distinct ideas, and the dualism of mind and body that will dominate European philosophy for the next three centuries. The cogito is not merely an argument; it is the prototype of a new kind of philosophical procedure in which the thinker begins by stripping away every belief that can possibly be doubted and rebuilds knowledge from whatever remains standing. Descartes would develop this procedure at full length in the Meditationes de prima philosophia of 1641; the Discours is the first public statement of it, compressed into eight pages that have been read more closely and more often than any other passage of seventeenth-century prose. Parts V and VI discuss the physics of Le Monde (including a detailed account of the circulation of the blood, drawn from Harvey’s De motu cordis of 1628 — the first discussion of Harvey’s discovery by a prominent foreign scholar) and the reasons for publishing the present book while withholding the larger work. La Dioptrique, the first of the three Essais, is ostensibly a treatise on the improvement of lenses and telescopes. In substance it is much more. Its second discourse derives the sine law of refraction — the relationship between the angles of incidence and refraction when light passes from one medium to another — independently of and earlier than the Dutch physicist Willebrord Snell, whose unpublished manuscript on the same law dates from the early 1620s but did not appear in print until Huygens published it posthumously in 1703. The law is fundamental: it governs the design of every optical instrument from Descartes’s day to the present. The fourth through sixth discourses develop a theory of vision and perception that rejects the scholastic doctrine of transmitted forms in favour of a mechanical account: the mind does not receive images resembling external objects but rather constructs perceptions from the motions that the optic nerve transmits to the brain. This is the first articulation of the representational theory of perception in its modern form — the thesis that the mind has access not to objects but to its own representations of them, a position that will structure the epistemology of Locke, Berkeley, Hume, and Kant. Les Météores is an eclectic collection of explanations of atmospheric phenomena — clouds, rain, snow, storms, coronae, parhelia — whose centrepiece is the explanation of the rainbow that is the most celebrated scientific result in the book. Descartes shows that the primary rainbow is produced by sunlight entering a raindrop, being refracted on entry, reflected once from the back of the drop, and refracted again on exit; the secondary bow results from a second internal reflection, which accounts for its greater height, reversed colour order, and reduced intensity. The analysis applies the sine law of refraction derived in La Dioptrique to the spherical geometry of the raindrop and calculates the angular radius of the bow to within half a degree of the observed value — one of the first successful applications of mathematical physics to a meteorological phenomenon. Throughout the Météores Descartes insists on demystification: phenomena that had been interpreted as omens or divine messages are to be understood as consequences of the mechanical properties of matter. He draws repeatedly on his own observations — snowflakes examined in Amsterdam in the winter of 1635, avalanches witnessed crossing the Alps in May 1625, coronae seen on the Zuiderzee — and distinguishes carefully between first-hand evidence and report. La Géométrie, the third and last of the Essais, is the mathematical masterpiece. Descartes warned readers at the outset that only those already trained in geometry would understand it, and that he had written it in haste while the Météores was on the press, inventing part of the content at that time. The warning was justified. Book I introduces the revolutionary step: the geometrical interpretation of the five algebraic operations (addition, subtraction, multiplication, division, and root extraction), the use of the new exponential notation (x³ for xxx) in place of the traditional cossic symbols, and the method of representing a geometric problem as an equation by naming unknown lines with letters and writing down the relations between them. The demonstration is the solution of the Pappus problem on four lines, a classical problem that had defeated the ancient geometers and that Descartes solves by the new algebraic method in a few pages. Book II introduces the classification of curves into “geometric” (those expressible by algebraic equations with integer exponents) and “mechanical” (all others), replacing the ancient Greek classification by ruler-and-compass constructibility with a classification by algebraic degree — the taxonomy that Newton would later extend to fractional exponents and Leibniz to transcendental curves. Book III treats the theory of equations: the rule of signs (the maximum number of positive roots of a polynomial is equal to the number of sign changes among its coefficients), the construction of roots by intersecting curves, and a systematic treatment of cubic and quartic equations using a circle and a parabola. The abundance and clarity of these results — some drawn from earlier work by Cardano, Harriot, and Girard, but here expressed for the first time in modern notation — would be taken up and extended by Newton in the Arithmetica universalis of 1707 and by every subsequent worker in the algebraic tradition. The Géométrie was, however, difficult — deliberately so, Descartes later admitted, to ensure that only competent mathematicians would claim to have understood it. Its European reception depended largely on the Latin translation and commentary published by Frans van Schooten the younger as the Geometria (Leiden, Maire, 1649), with the explanatory notes of Florimond de Beaune. The expanded second Latin edition of 1659–1661, which added commentaries by Hudde and de Witt, was the edition through which Newton, Leibniz, and the generation that created the calculus absorbed Descartes’s mathematics. The line of transmission is direct: Newton’s own annotated copy of the 1659–61 Geometria survives at Cambridge, and the Principia’s geometric demonstrations, for all their deliberate classicism, rest on the algebraic geometry Descartes had introduced here. The publication process was protracted. Descartes had come to Leiden in the spring of 1636 to find a publisher. Elzevier raised difficulties and offered poor terms; Descartes went instead to Jan Maire, a smaller Leiden printer who proved more accommodating. The woodcuts for the mathematical and scientific diagrams were made by Frans van Schooten the younger, son of the Leiden professor of mathematics, whom Maire lodged in his own house to speed the work and to prevent him from leaving. The Dioptrics was printed by October 1636; the Météores and Géométrie engravings caused delays. The Dutch privilege was granted on 20 December 1636 without difficulty, but the French privilege — necessary because the book was written in French — required the intervention of Mersenne and Constantijn Huygens and was not granted until 4 May 1637. Maire set the last folio on 8 June. Van Schooten later produced the Latin translation of La Géométrie as the Geometria (Leiden, Maire, 1649), with his own commentary and the explanatory notes of Florimond de Beaune — the edition through which Descartes’s mathematics reached the wider European audience that did not read French. The influence of the book is coextensive with the history of modern thought. Through the Discours and the Meditations of 1641 Descartes established the framework of mind-body dualism, the method of radical doubt, and the criterion of clear and distinct perception that would dominate European philosophy for three centuries — Locke, Leibniz, Spinoza, Malebranche, Hume, and Kant are all, in different ways, responses to the Cartesian programme. Through La Géométrie he created the mathematical language in which the physics of the succeeding century would be written: the calculus of Leibniz (1684) and Newton (1687) is algebraic analysis applied to geometric curves, and the technique that made that application possible is the identification of curves with equations that Descartes introduced here. Through La Dioptrique and Les Météores he demonstrated that mathematical physics could explain phenomena — the refraction of light, the geometry of the rainbow — that had previously been the province of qualitative natural philosophy. The title is accurate: this is a discourse on method, and the method worked. Provenance: Lessing J. Rosenwald (1891–1979), American businessman, collector of rare books and art, and philanthropist (small morocco monogram bookplate); given to the Library of Congress (bookplate and duplicate stamp) — Richard Green, physician and bibliophile (his sale, Christie’s New York, 17 June 2008, lot 87, $116,500). Dibner, Heralds of Science 81; Evans 5; Grolier/Horblit 24; Guibert, Bibliographie des œuvres de Descartes 1; Norman 621; Printing and the Mind of Man 129; Sparrow 54.
4to (203 x 152mm), pp. 78 [Discours]; [2], 413 [Essais], [1, Avertissement]; [34, tables, errata and French and Dutch privileges], woodcut printer's device on title, woodcut initials, numerous woodcut text illustrations and diagrams (some light spotting and browning, tiny associated hole on b4). Contemporary calf, red sprinkled edges (spine ends and corners restored, lightly rubbed, small split at head of upper joint); morocco pull-off case.
Item #6067
Price: $150,000.00
