Some unpublished fragments on Descartes’s life and works

ABSTRACT In this article I present some unpublished fragments concerning the life and works of René Descartes (1596–1650), gathered from the academic commentaries of Johannes de Raey (1620/1622–1702) on his treatises. The fragments, of different degrees of reliability, are important as (1) they reveal how the image of Descartes was shaped among his first followers and biographers; (2) they offer insights on his now lost manuscripts, to which De Raey had access after his death. They concern, amongst others, Descartes’s days at La Fléche, the original title of his Principia philosophiae, his inventum mirabile, a fragment of a conversation with him, and passages from an irretrievable French version of his Principia.


Introduction
Johannes de Raey (1620Raey ( /1622Raey ( -1702 can be labelled as the first who taught the ideas of René Descartes (1596Descartes ( -1650 in a systematic manner. He was first a student of Henricus Regius  at Utrecht in 1641, and later of Adriaan Heereboord (1613-1661 at Leiden, where De Raey enrolled in 1643 and graduated in arts and medicine in July 1647, becoming in the same year a private lector philosophiae. 2 As exemplified by the opening epigraph, he accepted Cartesianism without reservations, whereas Regius came to an open clash with Descartes in 1645, and Heereboord assumed a more syncretic approach, purportedly teaching some of Descartes's ideas along with Scholastic ones. 3 Still a private teacher, indeed, De Raey was so famous as a Cartesian that, at the suggestion of Tobias Andreae , in 1648-1649 Johannes Clauberg (1622Clauberg ( -1665 came to Leiden in order to perfect his understanding of Descartes's ideas under him. 4 Moreover, De Raey was praised by Descartes himself as being an excellent teacher of his philosophy, and was present, in March 1650, at the opening of the trunk of papers left by the latter at Leiden before moving to Sweden. 5 One year later, he was authorized by the University Curators to give public lectures and preside over disputations on pseudo-Aristotle's Problemata (in fact, a way to allow him to teach Descartes's physics), before becoming extra-ordinary (1653) and ordinary (1661) professor of philosophy, and leaving for the Amsterdam Athenaeum Illustre in late 1668, where he taught until his death. 6 De Raey is certainly an interesting figure for the exploration of Descartes's legacy, from the perspectives both of the reception of his scientific and philosophical ideas, and of the circulation of information and materials on his life and works. In this paper, I will offer new evidence on such issues by presenting and discussing some previously unpublished Cartesiana which are extant in De Raey's dictated lectures (dictata), namely in his commentaries on Descartes's treatises. After having presented in more detail the ways he could have access to information on Descartes's life and works (Section 2), I will provide an overview of his academic dictata (Section 3), and I will present the evidence gathered from these, concerning Descartes's life (Section 4.1) and texts (Section 4.2), discussing their reliability as genuine sources on Descartes, and advancing some hypotheses on their uses and significance.

De Raey's access to Cartesiana
As far as De Raey's contacts with Descartes are concerned, Descartes came to know about him first as a respondens in Regius's disputations at Utrecht in 1641, 7 before acknowledging his qualities as a teacher of his philosophy -as testified to by Clauberg,8 an acknowledgment which Clauberg could have heard during the only ascertained personal meeting between Descartes and De Raey, which took place at The Hague, together with Clauberg himself, probably in summer 1649. 9 Nonetheless, it is likely that De Raey and Descartes met more than once, as in the same year De Raey was asked by Roderich Dotzen (1618Dotzen ( -1670 to give Descartes his regards if they should meet at Leiden. 10 Moreover, De Raey was in contact with all the foremost Dutch Cartesians, and possessors of Cartesian manuscripts, such as the above-mentioned (1) Regius, who met Descartes more than once since 1639, 11 and was in possession of Cartesiana such as a copy a manuscript copy of Descartes's Traité de l'homme (like De Raey himself). 12 (2) Heereboord, labelled by De Raey as amicus (friend), who met Descartes in October 1642 and who was later in possession of a manuscript copy of his Traité de l'homme. 13 (3) Andreae, correspondent of Descartes (whom he met at least once), 14 whose father-in-law Louis de Geer was host of Descartes at Amsterdam. 15 In particular, Andreae was to provide Claude Clerselier (1614-1684) with letters belonging to Descartes's correspondence during or after 1654, and maybe with a copy of his L'homme. 16 (4) Cornelis van Hogelande (ca. 1590Hogelande (ca. -1662, probably the closest associate of Descartes at Leiden and holder of his trunk of papers. 17 (5) Frans van Schooten jr. , colleague of De Raey at Leiden, who took care of the preparation of the figures and woodcuts of Descartes's Essais and Principia, and was in possession of other Cartesian manuscripts. 18 To sum up, besides having met Descartes in person, De Raey was so well inserted in the circle of Dutch Cartesians that he could easily have access to information on Descartes's life and works.
Moreover, as mentioned above, on 4 March 1650 De Raey was present at the opening of a trunk that Descartes left to Van Hogelande at Leiden, as reported by Adrien Baillet (1649Baillet ( -1706 in his Vie de Monsieur Descartes (1691). The trunk contained, according to Baillet, "a packet of papers and letters", with which De Raey was acquainted, or "among various books and papers, some writings, and some letters from Mr. Descartes collected in a packet". 19 Its inventory is now missing, 20 and it was certainly unknown to Baillet, who around March 1690 asked De Raey (through Philipp van Limborch, 1633-1712, and Jean Le Clerc, 1657-1736 for information about such a packet. De Raey replied to him that the papers found in the 3. The academic dictata on Descartes's works Not surprisingly, indeed, we do find such kinds of information in De Raey's academic dictata, namely in those commentaries on Descartes's works that De Raey (like Clauberg, Christoph Wittich, Arnold Geulincx, Burchard de Volder, and others) [-quarta]. Amsterdam, University Library, ms. X B 7, ca. 1669-1702 Henceforth De methodo-Principia.
In particular, most of the Cartesiana can be found in additions to the main commentary on Descartes's texts, namely in marginal notes and parts of text which are in a clearly smaller size, or constitute paragraphs other than those of the commentary itself (which is structured as a series of commented lemmas). So it might be that De Raey did not include them in his main dictatum, but nevertheless communicated them to students: indeed, the additions to each commentary are by the same hand as the commentary itself. This is consistent with his recalcitrant approach in providing information on Descartes.

De Raey's Cartesiana
The Cartesiana extant in De Raey's dictata can be distinguished into three kinds: (1) information on Descartes's life, (2) information and extracts from Descartes's unpublished texts, (3) reports from conversations or oral statements by Descartes. Of course, the problem is that while (1) the fragments from Descartes's texts can be deemed as probably authentic (to the extent that De Raey had likely access to Descartes's manuscripts), the (2) information on Descartes's life at De Raey's disposal have more relevance for the study of what De Raey thought was Descartes's life, as they were most probably all at second hand, and (as I show below) mostly hagiographical. In turn, (3) the reports from conversations with Descartes have some sort of a status of reliability between these two kinds of evidence. The issue of the reliability of the biographical information conveyed by De Raey's lectures is in fact the same concerning the two early biographies Of these pieces of information, the first two (concerning optics and the theory of the Earth) are not mentioned by any source. The earliest known evidence on Descartes's optics trace to a fragment on refraction dating to ca. 1620 (when Descartes was 24 years old) and extant in Descartes's Cogitationes privatae. 41 According to John Schuster, the fragment "shows that Descartes was studying Kepler's optical masterpiece, the Ad Vitellionem paralipomena (1604) and that Descartes' text is a physico-mathematical 'reading' of a set of texts and figures in Kepler's work". In turn, Abdelhamid I. Sabra has argued that such a fragment contains the premises for the deduction of the sine law of refraction, presented in Descartes's Dioptrique (1637). A claim discarded by Schuster, who as convincingly argued that Descartes discovered the law of refraction only in 1626/ 1627. 42 Accordingly, De Raey's statement seems to be hagiographical, and can be useful -like many other biographical details conveyed by De Raey -for a study of the biographical literary tradition in the early modern age. 43 In any case, it can well date Descartes's earliest interests in optics back to 1611, nines year before the optical fragment, when Kepler's book had in fact already been published.
As for the letter to Galileo on the Earth's shells, there are no traces of it in the Favaro edition. It should have dated from 1616 at the earliest. Notably, at that time Galileo had published his Istoria e dimostrazioni intorno alle macchie solari e loro accidenti (1613): in turn, Descartes was to develop a theory of the formation of planets conceiving them as "dead stars", namely as stars completely enveloped by solar spots, which constitute the layers of the Earth itself. Such a theory was presented by Descartes in the fourth part of his Principia philosophiae, while in his Le monde (written in 1629-1633 -a text labelled by De Raey as an unpublishable sketch of his later Principia), 44 he does not offer a geological account of Earth, and does not touch upon the topic of sunspots (nonetheless discussed by him with Isaac Beeckman, 1588-1637, in 1629). 45 Accordingly, by proposing this (dubious) information De Raey aimed at stressing (like Borel) that Descartes can be considered as a peer of Galileo: a move whose purpose was to propose and use Descartes's Principia as an academic textbook.
With regard to the other information, Lipstorp reports the anecdote of Descartes's devising a method based on algebra, by which he could solve problems posed by a teacher of his at La Flèche. Moreover, he details that this teacher suggested that Descartes should read the writings of François Viète (1540-1603, whose manuscripts had been published by Van Schooten in 1646), but does not mention that Descartes was 15 years old at that time. 46 Accordingly, Lipstorp might have relied both on De Raey's and Van Schooten's accounts (as De Raey does not provide all the information given by Lipstorp, and at the same time he adds something not mentioned by him). In any case, as shown by David Rabouin, as late as in 1628 Descartes still showed robust "mathematical weaknesses" in proposing to Beeckman an algebraic method of solving problems in geometry, 47 so that, once again, such a story seems to be anecdotal, and designed for the attempt to propose Cartesianism as a philosophical alternative, probably shared also by Van Schooten. Lastly, the mention that Descartes read books just as stories echoes the judgment of school-books given in his Discours de la méthode. 48 (2) In his Analysis (ca. 1664-1668), concerning Descartes's Discours, we do find a similar anecdote, regarding Descartes's renowned first meeting with Beeckman:  [it]. From which fame spread that a French knight could solve geometrical problems, which even the most learned men had failed to do. So he found this key for all solutions, to such an extent that even a servant of his was very skilled in this.] Also in this case, we do find something not mentioned by Lipstorp, namely Descartes's increasing fame, and the fact that thanks to his method even a servant of his became skilled in mathematics. Again, Lipstorp relates Descartes to Viète, i.e., he compares this episode to Viète's solving, in three hours, a problem publicly posed by Adriaan van Roomen. Accordingly, Van Schooten was probably also a source of the story provided by Lipstorp (who reports also a further, similar anecdote, involving the Ulm mathematician Johann Faulhaber, not mentioned by De Raey). 50 Also in this case the anecdote has a remarked philosophical significance, as it echoes Plato's Meno, where a slave is brought by Socrates to solve a geometrical problem -both figures being indeed compared in this passage to Descartes, who is moreover treated as a nobleman (as Borel did). 51 Still, the anecdote is absolutely reliable, as the famulus was none other than Jean Gillot (1613/1614-1657), who had been in Descartes's service until 1632-1633, and himself became a private instructor in mathematics from the same year, being praised by Descartes in 1638 as "almost the only one in the world who knows the most about my method". 52 He was known to Van Schootenbut he was also a personal acquaintance of De Raey, who acted as intermediary between him and Dotzen in 1649. 53 (3) Also, in recalling a later episode in Descartes's life in his Annotata, commenting on Principia IV.72, De Raey mentions that Descartes instructed Johann Elichmann (1600-1639), teaching him how to conduct, in accordance with his philosophy, those experiments he had already made in several places at his own expense: Elichmann, an orientalist and physician practising at Amsterdam, met Descartes around 1629 and introduced him to Vopiscus Plempius. He died in 1639, being in that year recalled by Descartes among other acquaintances of his. 55 Actually, the earliest source on Descartes's experimental activities in chemistry is a letter of his to Mersenne of 15 April 1630, according to which he was conducting researches both in anatomy and chemistry, finding out new discoveries, and aiming such activities to the study of diseases and medicaments. 56 Accordingly, we can suppose that Descartes had started his activities in chemistry -viz. those reported by De Raey -around the late 1620s, and that from 1629 he could impart some teaching to Elichmann. In fact, little information is available on their relations. As detailed by Robin Buning, in 1631Henricus Reneri (1593-1639 planned to be instructed in chemistry by Elichmann, hoping that this teaching "could complete or at least greatly elucidate that general philosophy of Mr. Descartes". 57 [and] in which he wittily asserted, with many reasons, that he preferred Holland over Italy. However, his enemies not tolerating this prominent light, which is worth noting, [following] the example of Christ (no impiety intended), he wandered hither and thither for a long time, and eventually, desiring quiet, he withdrew to Egmond, in the remotest depths of Holland. The insults to our author have been so many (as it is to be seen in the Epistola ad Voetium) that the King of France complained about these, by letter, to the Orders of these Provinces, and Prince Frederick Henry interceded, with his authority, in these struggles.] In fact, between March 1629 and April 1635 Descartes lived for long periods at Amsterdam, where he wrote the above-mentioned letter to Jean-Louis Guez de Balzac (5 May 1631). 60 After other moves, he resided at Egmond aan den Hoef and Egmond-Binnen from May 1643 to September 1649 (with some visits abroad in the meantime). 61 De Raey's account is incompatible with Lipstorp's, 62 even if for De Raey it was just trivial, given his acquaintance with Descartes and his associates. The last episode recalls that of the mediation of the Stadtholder Frederick Henry with the magistrates of Utrecht during the querelle of 1643, when Descartes, accused of libelling against Voetius, was summoned by the Utrecht city council. The Stadtholder had been asked to intervene by the French Ambassador at The Hague (Gaspar de Coignet de La Thuillerie), and thanks to him the trial was suspended. In 1644, again, the Ambassador, upon Descartes's request, wrote to the States of Groningen complaining against Martin Schoock (the other protagonist, on Voetius's side, of the querelle). 63 However, no evidence of the intervention of the King of France to what appears to be the States of Holland and Westfriesland, if not the States General, is extant: whilst somehow correct -as the Ambassador was in fact representing the King of France -this was certainly an exaggeration by De Raey.

Extracts from Descartes's texts and conversations
Other information provided by De Raey concerns his texts and conversations, and can be considered as generally more reliable than De Raey's accounts of episodes of Descartes's life, as De Raey had most probably direct access to Cartesian manuscripts (as seen in Section 2). As follows:

A title for the Principia philosophiae
An interesting piece of information, reported by De Raey both in his Annotata and Analysis in commenting the title of the first part of Descartes's Principia philosophiae, is a previous title of such a treatise: namely Elementa philosophiae, which according to De Raey was reported on manuscripts of such a treatise, and was inspired by Euclid's treatise: In fact, we do find a textual trace corroborating Descartes's consideration of such a title in Principia II.64, in which Descartes compares his own principia to the elementa of geometry. 69 Moreover, such information allows us to shed some light on a long debated question, namely the supposed characterization, by Descartes, of his Principia as following a synthetic order of exposition, in contrast to his Meditationes, in which he purportedly followed an analytic order.
In his Responsiones secundae, Descartes differentiated between an analytical and synthetic way of demonstrating (ratio demonstrandi) in these terms: "analysis shows the true way by means of which the thing in question was discovered methodically", while synthesis "employs a directly opposite method [. . .]. It demonstrates the conclusion clearly and employs a long series of definitions, postulates, axioms". 70 As recently put by Lex Newman, "the analysis/ synthesis distinction turns on the handling of first principles. Analysis incorporates efforts to discover them; synthesis simply clarifies them. Successful analysis produces knowledge from its very foundations; successful synthesis merely helps to explain what we already know". 71 According to Descartes, moreover, "analysis [. . .] is the best and truest method of instruction, and it was this method alone which I employed in my Meditations. As for synthesis, which is undoubtedly what you are asking me to use here, it is a method which it may be very suitable to deploy in geometry as a follow-up to analysis". 72 In fact, Descartes was to use such a method of synthesis in his geometrical rendering of his Meditationes, at the end of his Responsiones secundae -exactly as Spinoza was to do in his Renati Des Cartes Principiorum philosophiae pars I et II more geometrico demonstratae (1663).
In turn, according to the so-called Entretien avec Burman (which took place between Frans Burman (1628-1679) at Egmond on 16 April 1648 and which is extant to us thanks to the report (or transcription of a report) that Clauberg made of it four days later at Amsterdam), in discussing his presentation of the proofs of the existence of God Descartes characterized his Principia as following a synthetic method, namely the order of exposition only. On the other hand, in his Meditationes he presented them by following the very order in which he discovered them: At this point the author is speaking of the sort of argument that can take some effect of God as a premiss from which the existence of a supreme cause, namely God, can subsequently be inferred. [. . .] By contrast, the other argument in the Fifth Meditation proceeds a priori and does not start from some effect. [. . .] In the Meditations that argument comes later than the one here; the fact that it comes later, while the proof in this Meditation comes first, is the result of the order in which the author discovered the two proofs. In the Principles, however, he reverses the order; for the method and order of discovery is one thing, and that of exposition another. In the Principles his purpose is exposition [docet], and his procedure is synthetic. 73 Historians have struggled in make sense of such an affirmation. 74 Edwin Curley, assuming the geometrical rendering of the Meditationes given in the Responsiones secundae as benchmark of what it means to be "synthetic", suggests that this indicates (1) the use of "formal definitions of important concepts", and the (2) "prompt and explicit recognition of eternal truths". 75 This in fact fits the differentiation between the two texts, as "in the Meditations [. . .] we find whole chains of reasoning, including false starts, heuristic arguments meant to motivate particular premises", while "in the Principles and in the Geometrical Appendix [. . .] there are no false starts or dead ends, and little heuristic argument. The proof and its premises are presented unadorned and bare". 76 As put by Garber, "following Curley's line of thought, one might point out that the Meditations are written in the first person, while the Principles and the Geometrical Appendix are both written impersonally", and this is exactly what Wittich remarked in his commentary on Descartes's Principia. 77 However, for him while Curley shows us how the concepts of analysis and synthesis can be made to fit the Meditations and the Principles, neither [. . .] has established with sufficient evidence [. . .] the claim that Descartes really saw the distinction between analysis and synthesis as being relevant to the differences between the Meditations and the Principles. [. . .] The direct evidence that Descartes wrote the metaphysical part of the Principles synthetically is very weak. The only textual evidence for this claim comes from the Conversation with Burman. But, it must be remembered, these words are not from Descartes' own hand. They are filtered through Burman and almost certainly through Clauberg. 78 Obviously, also the pieces of information provided by De Raey and Wittich were filtered. But such pieces corroborate the claim, given in the Entretien, that the Principia follow a synthetic order in the meaning clarified by Curley. Indeed, they reveal that the first model of exposition about which Descartes thought in conceiving his Principia was that of the geometrical exposition of Euclid.
But when did Descartes adopt such a title? After having used for the first time the phrase "principles of my Philosophy" (principes de ma Philosophie) in a letter to Mersenne of April 1634, 79 the first mentions of his publication project trace to 1640. On 12 May 1640, indeed, Jean Chapelain wrote to Balzac that, thanks to Kenelm Digby, Descartes was going to move to England to print his Physique. 80 At least Chapelain's claim about the publication project had some foundation, as on 30 September Descartes asked Mersenne to provide him with some bibliographical information on Scholastic treatises: in particular, to recommend to him an abregé of them, by which he could refresh his memory on Scholastic theories. 81 Later (11 November), he communicated to Mersenne his appreciation of the Summa philosophica quadripartita (1609) by Eustache de Saint-Paul (1573-1640), and his intention to put on paper the "principles of my Philosophy" (principes de ma Philosophie) within one year. In particular, Descartes  Eventually, on 31 December Descartes pointed out that [. . .] this year, which I have resolved to employ in writing my Philosophy [Philosophie] in such order that it can easily be taught. And the first part, which I am doing now, contains almost the same things as the Meditations that you have, except that it is entirely in another style, and that what is put in one at length, is more abbreviated to the other, and vice versa. 83 Thus far, Descartes clearly presented his Philosophie as following an order aimed at teaching and different from that of his Meditationes. As he mentioned the use of drawing theses as conclusions in his previous letters, it is clear that he had in mind the synthetic order as characterized in his Meditationes.
Later, during 1641 Descartes labelled his treatise as Physique, Summa philosophiae, Sommaire de toute la Philosophie, 84 while in January 1642 he declared he had chosen the Latin title of Summa philosophiae -as he had to make his book read by the Scholastics. 85 Such a title was in any case soon abandoned, as from March 1642 up to February 1644 Descartes refers to his treatise just as his Philosophia, Philosophie, Physique, 86 and -as reported by Baillet in his paraphrase of a letter of Descartes to Claude Picot of 2 February 1643 -Principes de Physique. At that point, the use of Principia seems to have been chosen by Descartes, although Baillet might just have used the final title in order to clarify what was the treatise dealt with in the letter, in which it is also referred to as Physique. 87 Some months later, according to a letter of Samuel Sorbière to Thomas Martel of 15 June 1643, a part of Descartes's Meditationes physicae (sic) was to appear soon, as the treatise itself was in course of printing at Amsterdam. 88 If this information is true -but we can doubt it, as I show in a moment -, such a part was certainly the first one (which included the very title of the treatise, Principia), as the second one contains figures which were not started to be prepared by Van Schooten until September 1643. 89 The printing of the treatise, in fact, most probably began at the end of the same year, while he nonetheless was still working on part 4, as reported by Descartes on 1 January 1644, at which point the title of Principia philosophiae was certainly definitive. 90 To sum up, the use of such an expression -"principia" -is recurrent in Descartes's correspondence, but was definitive, as a title, only since the second half of 1643. Before that (1641-1642), the concurring title was that of Summa, of an evident Scholastic inspiration, which Descartes kept at least until January 1642. Given the fact that De Raey reports that Elementa philosophiae could be read on certain manuscripts, such a title could not date to a time when Descartes was still conceiving his publication project: namely in November 1640, when, as seen above, Descartes was planning to write his treatise in form of duly argued conclusions, i.e., was planning to follow a synthetic order of exposition. Rather, Elementa was probably an intermediate title between the Summa and the Principia, and used by Descartes in 1642-1643.
As to De Raey's knowledge of such a title, we can presume that he had access to one or more manuscripts including parts 1-2 (which were certainly finished before he adopted the title of Principia in 1643), and maybe part 3 of Descartes's treatise. Indeed, between December 1640 and July 1641 Descartes had just started his treatise. 91 In April 1643 -after having been delayed by the polemics with Voetius and Pierre Bourdin -he was working on part 3 (on the heavens, which is the overall topic of the part, and, in particular, on planets (III.6-37 and 139-157)), 92 and one month later (May) was about to write on magnetism, after having explained the origin of the two kinds of subtle matter (III.48-52). 93 In turn, in January 1644when the printing of the treatise had begun -he was finishing the part on magnetism (IV. , after having completed the whole part 3 of his treatise (a section of which was under press at that time). 94 To sum up, in May 1643 Descartes certainly had written a substantial part of the third part of his treatise, before assuming the final title of Principia when the book started to be printed. In any case, how De Raey could see a manuscript of Descartes's treatise -if he had direct access to it -is only a matter of guesswork. Indeed, there is no extant evidence that Descartes circulated a draft of his book, and De Raey might just have found it among the manuscripts contained in the Leiden trunk. Alternatively, he could have had this information from the Cartesian circle in the Netherlands: in fact, Descartes kept Regius himself updated about his Philosophia in early 1642, and also Heereboord knew about his publication plans. 95

The inventum mirabile
Moreover, in his Annotata De Raey overtly refers to a manuscript found after Descartes's death. He does so in commenting on Descartes's narration, given in his Discours, of his staying in a stove-heated room, in Germany, during the Winter 1619-1620, which is worth quoting in full: I stayed all day shut up alone in a stove-heated room, where I was completely free to converse with myself about my own thoughts. Among the first that occurred to me was the thought that there is not usually so much perfection in works composed of several parts and produced by various different craftsmen as in the works of one man. 96 In commenting such a pensée by Descartes, De Raey remarks as follows: This is indubitably a reference to one of the greatest episodes of Descartes's intellectual venture, namely his inventum mirabile, mentioned in his Olympica, which has since long attracted the attention of historians. Amongst others, both Geneviève Rodis-Lewis and Stephen Gaukroger have related the inventum to the development of a science by one man only as expounded in Descartes's Discours, as De Raey himself does, with the evident aim of stressing the foundational approach of Descartes, which became a trademark of Dutch Cartesianism. 98 At first sight, De Raey's reference seems to trace to Borel's 1656 Vitae Renati Cartesii Compendium, 99 which contains an abridged, Latin version of the so-called "Stockholm inventory", reporting the following item: "C. Olympica and, on the margin, '11 of November, I started to understand the foundation of the admirable discovery'". 100 [. . .] in form of a discourse, titled Olympica, which was only 12 pages long, and which contained in the margin, in a more recent ink, but still by the same hand of the author, a remark which even today gives [occasion] of exercise to the curious. The words in which this remark was conceived stated "11 of November, I started to understand the foundation of the admirable discovery", of which [neither] Mr. Clerselier nor the other Cartesians could give us an explanation yet. This remark is found opposite a text which seems to persuade us that this writing is posterior to the others which are in the notebook, and that it was not started until the month of November of the year 1619. This text bears these words [in] Latin: "10 of November 1619, being full of enthusiasm, and finding the foundations of the admirable science, etc." 102 While providing a second quotation from the Olympica, Baillet informs us about the exact date of the inventum, enabling it to be traced to the Winter of 1619-1620. Moreover, such a second quotation has two notable features: (i) it has a decidedly more vivid and "enthusiastic" overtone than the first quotation, and fitting more the overtones of De Raey's commentary; (ii) it is reported in an abbreviated form by Baillet ("etc."), while De Raey provides the detail that Descartes mentioned a discovery which surpassed, by far, any previous discovery by him. Given the fact that in 1653-1654 such a registre en parchemin was brought by Pierre Hector Chanut (1601-1662) to The Hague together with his other Cartesian manuscripts, and that he allowed Christiaan Huygens (1629Huygens ( -1695 to inspect them (as reported by his father Constantijn to Elisabeth of Bohemia, 1618-1680), it could be that the registre was read by De Raey as well, or that its contents circulated in the Netherlands. 103 After all, the young Huygens was privately mentored by Van Schooten during his studies at Leiden University in 1645-1647 and afterwards he kept close contact with him, while his father Constantijn was a foremost sympathizer of Cartesianism. 104

Another victoria
A similar piece of information, provided in his Annotata, concerns another occasion in which Descartes rejoiced for a discovery of his, namely, as he devised the theory (exposed in Principia I.66) that one can have a clear knowledge also of sensations, passions and appetites, provided that one formulates judgments on their contents only: Such an anecdote appears to be functional to De Raey's strategy of differentiating between philosophical and practical knowledge, based respectively on understanding and sense perception. A radical differentiation quite at odds with Descartes's philosophical project of grounding on philosophy practical disciplines like medicine and morals, 106 and which De Raey started to develop with his Dissertatio de cognitione vulgari et philosophica (1651), and that had its ultimate outcome in his Cogitata de interpretatione (1692). In his Cogitata, De Raey provided a detailed analysis of linguistic expressions by distinguishing, above all, between their signifying passions, sensations and appetites in a philosophical sense, i.e., as modifications of the soul of which we can have a clear knowledge, and in a "vulgar" sense, i.e., as modifications of our or external bodies, to which we improperly or confusedly refer when we employ names of sensations out of philosophical contexts, as in theology or medicine. 107 This approach to the study of language by De Raey was in fact made possible by Descartes's victoria mentioned in the dictata. It remains unclear, however, if De Raey found this information in a manuscript by Descartes, if it was revealed during a meeting with him, or if it is just an anecdote.

Conversations with Descartes
In any case, De Raey certainly gained insights from a famous conversation or interview involving Descartes, the above-mentioned Entretien avec Burman. Some extracts of it are provided by Clauberg, who provided the report of it, in his Defensio Cartesiana (1652), 108 in his Notae (ca. 1654-1655) on Descartes's Meditatio prima published as chapters 7-9 of his Initiatio philosophi sive Dubitatio Cartesiana (1655), 109 and in his De cognitione Dei et nostri exercitationes centum (1656). 110 In turn, in his Dictata in Meditationes (ca. 1657-1658) De Raey reports a passage whose contents can be found both in the Entretien and in Clauberg's Notae (as evident from the textual comparison given in Appendix 1, case of lemma "a sensibus vel per sensus"). However, De Raey did not just rely on Clauberg's Notae, and most probably obtained a copy of the Entretien itself. Indeed, it is De Raey who makes explicit that the commentary comes from a direct question to Descartes (while Clauberg's text is more vague). 111 Moreover, in his Annotata, in commenting Descartes's famous passage, from the Discours, Those long chains composed of very simple and easy reasonings, which geometers customarily use to arrive at their most difficult demonstrations, had given me occasion to suppose that all the things which can fall under human knowledge are interconnected in the same way. 112 De Raey reports a second extract, which cannot be found in Clauberg's printed texts: The same contents (consistent with De Raey's differentiation between practical and theoretical knowledge) can be found in the Entretien, in a question relating to the same passage commented by De Raey: [Burman:] But is it not the case that in theology too all the items are mutually related in the same sort of sequence and chain of reasoning? [Descartes:] Undoubtedly they are. But these are truths which depend on revelation, and so we cannot follow or understand their mutual connection in the same way. And certainly theology must not be subjected to our human reasoning, which we use for mathematics and for other truths, since it is something we cannot fully grasp. 114 Perhaps more interestingly, De Raey had access to the contents of a previously unknown conversation involving Descartes, as testified to by his commentary on Descartes's Principia III.71, concerning the centrifugal movement of subtle matter within a vortex, given in his Annotata: De Raey refers to a colloquium (other than the Entretien) 117 between Descartes and a friend: so he seems not to have been present at it. It reveals how Descartes conceived the spatial disposition of vortices, as a space filled by bubbles (cf. Figures 1 and 2). 118 Such a way of theorizing the spatial disposition of vortices has already been noticed by historians, 119 but De Raey's dictata shed new light on it, as his words confirm that the use of analogy and imagination had a foremost role in the development and exposition of Descartes's physics, allegedly based on purely intellectual ideas and chain of reasoning only. As Christoph Lüthy put it, Descartes's "figurae constitute one of the facets of Descartes's 'clear and distinct ideas', [and] serve as a bridge between logical deduction and rhetorical persuasion", as "the further he moves away from his first principles and the more he approaches the level of specific physical phenomena, the more he must invoke sensory experience, argue hypothetically, base his suppositions on analogies". 120 To put it otherwise, beyond the abstract image of the vortices (Figure 1) there is nothing but the imagination of bubbles of sea-foam ( Figure 2) -and Descartes himself at some point admitted this. [Intelligence: [. . .] the swiftness of thinking depends on the strength of the spirits. Therefore, the author said that the French are not capable [of understanding] his philosophy, but rather they have to be addressed to commerce, rhetoric, and poetry, because of their great swiftness in thinking.

Descartes on the French
Enough time: such is the intelligence of the Italians, as well as of the French, who therefore the author considers inept to learn his philosophy. And because of this petulance of the French, many [of them] become used to mathematics, in order to calm [their] soul. However, a swift intelligence has a great advantage: admittedly, it avails much to medicine, poetry, jurisprudence, languages, and commerce.] Such statements apparently develop on the classical idea of the sanguine temperament of the French, 123 and on the idea (overtly endorsed by Descartes in his correspondence with Elisabeth of Bohemia), that the agitation of spirits disposes those provided with a firm brain to poetry, as it excites the imagination. 124 Such statements are consistent, moreover, both with De Raey's recurrent attempt to differentiate between philosophical and practical disciplines, and with the harsh contempt towards the French that he was to show to Baillet (as seen above), which he re-stated during a disputation taking place at Amsterdam in June after the publication after Baillet's Vie, a book which De Raey labelled as "vain and the most full of lies [. . .], adding the reason that this is not surprising, having been written by a Frenchman". 125

Fragments from a French version of Descartes's Principia
Lastly, is worth mentioning that in De Raey's dictata we do find three passages attributed by De Raey to the French version of Descartes's Principia, but in fact absent in all the printed editions of this treatise. It is the case of the commentaries on Principia III.83, IV.18, and IV.189, which I illustrate in Appendix 2. Of course, it might be that these were just misattributions by De Raey, who in his dictata suggests several additions and corrections to the Latin text of Descartes's Principia, overtly or covertly drawing them from his Principes. 126 However, one of the passages dictated by him echoes Descartes's words from the Entretien, concerning the same lemma from Principia III.83 as in Appendix 2. This cannot be coincidental: given the fact that thanks to Burman's questions Descartes came to reflect again on his Principia, he could afterwards have put his reflections on paper, in French. Notably, in the so-called Stockholm inventory are mentioned "sixty-nine sheets, whose continuation is interrupted in several places, containing the doctrine of his Principia in French and not entirely consistent with the Latin print". 127 As reconstructed by Matthijs van Otegem, such sheets were, teste Jean-Baptiste Legrand, by Descartes's hand. It was on the basis of this evidence that Legrand, therefore, wrongly labelled the articles from III.41 to the end of Descartes's Principia as having been translated by Descartes himself (a claim in fact contradicted by some contents of Descartes's correspondence, testifying that the whole text was translated by Picot). 128 Therefore, such sheets contained a copy, by Descartes, of the French translation of the articles of the Principia from III.41 onwards, including of course III. 83,IV.18,and IV.189. 129 It might be that the variants reported in De Raey's dictata were written by Descartes in such a manuscript, to which he could have access along with Descartes's Olympica. In any case, the variants reported in De Raey's dictata are absent in the French editions of the Principia which appeared in 1668 (Paris, Girard), bearing the sub-title Revised, and corrected in this last edition (Reveus, et corrigez en cette derniere edition -by an editor whose identity could not be ascertained), and, more notably, in 1681: this bears the sub-title Revised and corrected very exactly by Mr. CLR (Reveuë et corrigée fort exactement par Monsieur CLR, Paris, Girard, this being the only edition bearing such a subtitle), and was apparently edited by Clerselier, who had received from Chanut such sheets from Stockholm. Therefore, De Raey might have seen such additions on another manuscript: for instance, one of the papers contained in the Leiden trunk. In fact, De Raey's own disclosure of the original title of this treatise (Elementa philosophiae) reveals that he had access to a further manuscript version of Descartes's treatise. In any case, such 1668 and 1681 editions contain negligible variants with respect to the first French edition (1647), 130 so that we can suppose that they were prepared without any collation with a manuscript, and even that Clerselier did not take part in their editing. In turn, De Raey edited the text of the 1656 Elsevier Latin edition of Descartes's Principia, correcting the typographic errors present in the previous editions, but he did not provide any addition to the text. 131  Raey,Annotata,11. This text is an addition. The use of italics indicates the commented lemma. The commentary is on "totos dies solus in hypocausto morabar, ibique variis meditationibus placidissime vacabam", AT VI, 545. Cf. the original French: "je demeurais tout le jour enfermé seul dans un poêle, où j'avais tout loisir de m'entretenir de mes pensées", AT VI, 11. See also infra, n. 97. 41. AT X, 213-256. 42. Sabra, Theories of Light, [105][106][107][108][109][110]153 and chapter 4. 43. On early modern biographies see Ribard,Raconter. 44. See supra,n. 27. 45. Schuster,chapters 8 and 12. 46. "Hanc enim eius fuisse perpetuam consuetudinem, ut mane experrectus in reclinatorio suo ad clarum usque diem meditabundus iaceret, norunt illi, qui ipsum familiarius noverunt, quique tunc eius ingenii vires saepius sunt periclitati. Hac ratione invenit speciosam suam algebra, omnium liberalium artium et scientiarum clavem, optimam verum a falso dignoscendi methodum. Hanc veritatis ducem cum securius in dies persequeretur, et interea in vulgari analysi geometrica a praeceptore suo exerceretur, id consequutus, ut non tantum dexteritate ingenii aliis suis in hocce studio analytico commilitonibus palmam praeriperet, sed et praeceptoris exspectatione opinione citius maior factus, nihil iam amplius, quantum ad analysin istam spectaret, sibi proponere permitteret, quod non miro artificio protinus solveret. Imo ipsum praeceptorem, in algebraicis forsan non tam exacte versatum, novis quaestionibus ita defatigavit, ut eum non amplius sua informatione indigere ingenuo testimonio confirmaret. Erat autem ipsi paulo ante difficilior quaestio a magistro proposita, quam per novam suam methodum artificiose solverat, solutaeque copiam magistro fecerat. Is novum solvendi modum per quantitates quasdam simplices, post habitis numeris, conspicatus, ipsum monuit, ut Viëtam consuleret, qui eiusdem argumenti nonnulla concinnaverat. Tum ille gaudio ingenti delibutus, quod alium quoque huius methodi peritum extitisse intellexerat, non destitit praeceptorem rogare, ut sibi huius copiam facere", Lipstorp,Specimina,75 Borel, Compendium, 5 and 7. 63. Verbeek, Descartes and the Dutch, 29-31;Verbeek, "Johannes Clauberg", 182-183;Descartes, Correspondence 1643, 183-192;Clarke, Descartes, 242-243. 64. De Raey, Annotata, 98. 65. De Raey, Analysis, 8v