RACONIS, CHARLES FRANÇOIS D’ABRA DE (ca. 1580–1646). De Raconis taught philosophy at the Parisian colleges of des Grassins and du Plessis (from circa 1610 on) and held a chair in theology in the Collège de Navarre, Paris, in 1616. He published a philosophy textbook, Summa Totius Philosophiae (1617, with many editions variously titled until 1651). He became bishop of Lavaur in 1637. Descartes read de Raconis’s Summa in the 1640s when he was seeking a widely read summary of scholastic philosophy with which he could compare his philosophy.
RAEY, JOHANNES DE (1622–1702). There is little we know of Johannes de Raey (or Raei) before he is mentioned as a student of Henricus Regius in one of Descartes’s letters. Without graduating he moved to Leiden in 1647, where he took degrees in philosophy and medicine and settled as a highly successful private teacher in philosophy. Despite the fact that he was an outspoken Cartesian, Leiden University gave him an extraordinary professorship in philosophy in 1651, stipulating that he should lecture on Aristotle’s Problems. In fact he taught Cartesian natural philosophy, allegedly with the aim of showing that there is fundamental agreement between Aristotle (as opposed to the Aristotelians) and Descartes. This is also the theme of his first book, a compilation of disputations called Clavis philosophiae naturalis, sive Introductio Aristoelico-cartesiana in contemplationem naturae (“A Key to Natural Philosophy, being an Aristotelico-Cartesian Introduction to the Contemplation of Nature,” 1654). The use of the expression “contemplation of nature” indicates a second theme, which would become more and more important, namely, the idea that philosophy is pure contemplation and has nothing to do either with practical problems or with the disciplines taught in the “Higher Faculties” (theology, medicine, and law). Accordingly, De Raey emancipates philosophy from its propaedeutic role in the academic curriculum (it is no longer an introduction to theology, medicine, and law), but at the cost of philosophy’s practical relevance. In 1669 conflicts with his Leiden colleagues led De Raey to accept an appointment at the Atheneum Illustre of Amsterdam, where this theme was further developed, especially against Baruch Spinoza and his friends.
This culminated with a theory of language, which he developed in his last work, Cogitata de interpretatione (“Thoughts on Interpretation,” 1691). According to this theory the meaning of a word is an idea. But there are two types of ideas: the clear and distinct ideas of science, which are innate, and the obscure and confused ideas of experience, which the mind acquires in cooperation with the body. These two systems of ideas are separate and accordingly form the basis of two separate linguistic systems: the language of science (virtually the language of mathematics), which refers to the clear and distinct ideas we find in ourselves, and ordinary language (or any form of language that is parasitical on daily language), which refers to the ideas of the senses. Since, on the other hand, practical problems are formulated in daily language, it is impossible that philosophy, which is the domain of the language of science, can contribute anything to their solution. More particularly, philosophy cannot contribute anything to theology, given the fact that the text of theology, Holy Scripture, was written in ordinary language. Although in his best moments De Raey seems to anticipate some of the problems Immanuel Kant (1722–1802) would still be grappling with, there is a lot of confusion, especially in his later work. More specifically, he cannot solve the problem of how to relate physics to the “real” world, that is, the world we experience with the senses.
RAMUS, PETRUS (PIERRE DE LA RAMÉE, 1515–72). Philosopher, rhetorician, and the most eminent logician of his day. Born in Cuts in Picardy, Ramus enrolled at the Collège de Navarre in Paris, receiving the magister artis in 1536. He defended the thesis entitled Quaecumque ab Aristotele dicta sunt, commentitia sunt (“Everything taught by Aristotle is a fabrication”), a topic showing the extreme novelty of his views on philosophy and method. He taught a reformed version of Aristotelian syllogistic logic at the Collège du Mans, in Paris, and at the Collège de l’Ave Maria, where he worked with Audomarus Talaeus (Omer Talon). Talaeus, under Ramus’s influence, reformed Ciceronean rhetoric upon the principles applied by Ramus to the rearrangement of Aristotle’s works on logic. As part of his project for the reform of Aristotelian logic, Ramus published Dialecticae partitiones (“The Parts of Dialectic”) and Aristotelicae animadversiones (“Aristotelian Thoughts”), both in 1543. These works so provoked the orthodox Aristotelian philosophers at the University of Paris that they induced Francis I in 1544 to suppress them and forbid him to teach. After a public disputation on the matter, Ramus was denounced as “rash, arrogant and impudent.” Through the influence of Cardinal Charles de Lorraine, Henry II lifted the ban against Ramus in 1547, and in 1551 he was appointed regius professor of philosophy and eloquence at the Collège de France. In 1562 he converted to Protestantism; mounting persecution from his academic and ecclesiastical enemies marked the last years of his life. Hired assassins murdered him two days after the outbreak of the Massacre of Saint Bartholomew’s Day in August 1572.
Ramus identified logic with dialectic, neglecting the traditional role that logic played as a method of inquiry. Instead, he emphasized the view that logic is a method of disputation, its two parts being invention, the process of discovering proofs in support of a thesis, and disputation, which taught how the material of invention should be arranged. Ramus’s logic had enormous vogue in Europe during the 16th and 17th centuries.
RAREFACTION AND CONDENSATION. Certain fluids, notably air, appear to be capable of occupying larger or smaller volumes without the addition or subtraction of matter. Certain kinds of stuff, iron for example, weigh more per unit volume than do other kinds like wood. Atomists explained these phenomena by supposing that empty space can be more or less completely filled by matter; density is then the proportion of occupied space. Philosophers who denied the existence of empty space had to find another explanation. Some Aristotelians followed Ægidius Romanus and other medievals who held that the same quantity of matter can occupy different volumes in space. Others held that the density of a body is determined by the number and size of the pores or interstitial spaces it contains. Those spaces are filled with particles of air or subtle matter, and do not contribute to the heaviness of the body. Descartes, who denies even the possibility of empty space, adopts the second sort of explanation (Principles II, art. 5–7, AT, VIIIA, pp. 42–44), holding that “no more intelligible explanation can be given” than his. Experimental evidence on behalf of the vacuum (see extension) undermined Descartes’s denial of its possibility, and thus also his explanation of rarefaction and condensation.
REAL ACCIDENTS. See QUALITIES, REAL; SUBSTANCE.
REASON. Descartes identifies reason with “good sense” or “the power of judging well and distinguishing the true from the false” (Discourse on Method I; AT, vol. VI, pp. 1–2). This account is broadly consistent with the Aristotelian model of reason as a discursive faculty that enables the mind to draw inferences and to distinguish reality from appearance. When applied properly, that is, when restricted to drawing conclusions on the basis of clear and distinct perceptions, reason is infallible: it cannot arrive at a false conclusion. This complete reliability of reason is ultimately underwritten by the benevolence of God, since it would be inconsistent with the divine nature to deceive people when they restrict their use of reason to clear and distinct ideas. The faculty of reason is also wholly present in every person—the differences in intellectual attainment among people are due to their greater or lesser exercise of reason, but the faculty itself “remains one and the same” in all persons (Rules for the Direction of the Mind, Rule 1; AT, vol. X, p. 360). Another important feature of the capacity to reason is that it distinguishes humans from animals. According to Descartes, the inability of brute animals to use language shows “not only that the beasts have less reason than humans, but that they have no reason at all” (Discourse on Method, Part V; AT, vol. VI, p. 58).
REFRACTION. See OPTICS.
RÉGIS, PIERRE-SYLVAIN (1632–1707). French natural philosopher and a prominent promoter of Cartesianism. Régis was converted to Cartesianism in the late 1650s by the famous Paris conferences of the Cartesian natural philosopher Jacques Rohault. He was sent as a Cartesian missionary to Toulouse during the 1660s, and he lectured with great success both there and, in the 1670s, in Montpellier. He returned to Paris in 1680 to revive Rohault’s conferences (Rohault having died in 1672), but the conferences were suspended due to controversies surrounding the Cartesian account of transubstantiation, which the Jesuit Louis Le Valois had criticized as Calvinist in a pseudonymous work that same year. These controversies also led to Régis’s failure to receive permission to publish his grand Système de philosophie, a work that was not published until 1690. The section of this text on metaphysics takes over Robert Desgabets’s interpretation of Descartes’s doctrine concerning the creation of the eternal truths, and also endorses Desgabets’s view that ideas of substances require real external objects and that our temporal thought requires a union with motion.
In the early 1690s Régis published Cartesian responses to the critiques of Descartes in the work of the skeptic Pierre-Daniel Huet and the scholastic Jean Duhamel. The focus here was primarily on Descartes’s views concerning the cogito and the method of doubt. In the middle of this decade, he entered into a dispute with the Cartesian Nicolas Malebranche and his disciple Henri de Lelevel. Part of this dispute concerned the question of why the moon appears to be larger on the horizon than it is on the meridian. Régis’s answer appealed to the distorting effects of the atmosphere, while Malebranche and Lelevel emphasized the effect of natural judgments. The main issue between these antagonists, though, concerned the view in Malebranche that the ideas we perceive exist in God. Régis countered by defending the position, which Antoine Arnauld had offered a decade earlier against Malebranche, that our ideas are only modifications of our mind.
Régis and Malebranche were admitted together into the Paris Académie des sciences in 1699. Régis’s final publication was L’Usage de la raison et de la foy (1704), which argues that faith and reason do not conflict since reason is infallible only in the realm of nature while faith is infallible only in the realm of grace. This work also includes, as an appendix, a response to the first half of the first part of Baruch Spinoza’s Ethics. Two striking features of this response are its concession to Spinoza that divisible bodies are only modes of one indivisible material substance, and its claim that God is not a substance but rather a “supersubstantial” being.
REGIUS, HENRICUS (1598–1679). Henricus de Roy (the Latinized form Regius was used only after he became a professor) was born in Utrecht. His parents died from the plague when he was still a youth and he was brought up by an uncle, who sent him to Franeker and Groningen to study medicine. In his student days Regius traveled extensively (Paris, Montpellier), obtaining his degree at the University of Padua. On his return to the Netherlands he became town physician (in charge of the care for the poor) in Utrecht and later head of the Latin School (secondary education) in Naarden near Amsterdam. Naarden was also the place where the orthodoxy of his beliefs first came under attack: his conflict with the local minister was brought before the Church Council of Amsterdam and ended only by his formally renouncing the incriminated opinions concerning the resurrection of the body. In 1638 he became professor extraordinary (reader) of theoretical medicine and botany at the University of Utrecht; in 1639 he became an ordinary professor. The rector of the university, Gysbertus Voetius, granted him the right to lecture and dispute on general philosophical questions in 1641, a right that was withdrawn in 1642 after he had been the center of a row over Cartesianism. In 1646 he published a work on natural philosophy, Fundamenta physices (see below). A new edition, Philosophia naturalis (1654; reprinted 1661) has a more systematic structure. Until the publication of Descartes’s Treatise on Man (in Latin translation in 1662) Regius’s works on theoretical and practical medicine were the only Cartesian textbooks in that field.
Before his appointment at the university Regius gave private lectures on philosophy based on his reading of Descartes’s Dioptrics and Meteors. The fact that these were very successful with students may have been one reason for giving him a chair. But the fact that a new chair was created was undoubtedly the result of the skillful machinations of the professor of philosophy, Henricus Reneri, a friend of Descartes who was also on very good terms with the first burgomaster of Utrecht, Gysbert van der Hoolck (1598–1680), who governed the university on behalf of the town. This explains why in his first letter to Descartes Regius thanks Descartes profusely.
For Regius the friendship with Descartes was very stimulating. He obviously was aware of the revolutionary character of Descartes’s ideas and also sensed the immense advantages medicine could draw from Cartesian physics. From the point of view of Descartes, the friendship with Regius was doubly attractive. Not only did he find in Regius an intelligent interlocutor, he also understood that Regius was in a very good position to make propaganda for his ideas. Still, from the beginning there were differences in their orientation and, possibly, their temperament and character, which after some years became fatal for their friendship. First of all, Descartes may have underestimated Regius’s ambition. Although Regius was a loyal supporter of Descartes, he presumably did not want to be known as being no more than a follower of Descartes. Moreover, Regius was a professional physician but he was an amateur in philosophy, sometimes confusing and blending ideas of different origin and being altogether much more empirically minded than Descartes. And, finally, as compared to Descartes, Regius was much less sensitive to the religious and theological implications of his position—or, others would say, more naive.
These differences, which occasionally played a role even at the beginning of their friendship, became fully manifest in 1645 when Regius submitted to Descartes the manuscript of what he planned to be his first publication for a larger audience, the Fundamenta physices. Descartes’s reaction was one of disappointment (he thought that Regius did too little to prove his views) and, when he reached chapter 12 (On Man), his reaction was one of shock, because it showed that on many metaphysical issues Regius took a line that was completely different from his: that as far as natural reason is concerned the mind could be a mode of the body as well as a separate substance; that the existence of the world is uncertain; that it is impossible to prove the immortality of the soul; that to think we do not need innate ideas; that the presence of an idea of God in ourselves is not enough to prove the existence of God, etc. In a general way Regius solved these and similar questions by calling in the evidence of Scripture—even if we cannot understand how mind and body are related or cannot certainly know that an external world exists, the authority of Scripture is enough to convince us that the soul does not die with the body and that God created the world. But Descartes also found that Regius’s method of presentation was weak. In his view his method could be appropriate for disputations but was unfit for a work that was meant to convince. He urged Regius to suppress certain passages, which Regius did to a certain extent, but was so infuriated by the way Regius reacted to his suggestions that he broke with him.
After the book was finally published in 1646 Descartes complained about it in letters to Marin Mersenne and Princess Elisabeth, accusing his former friend of plagiarizing as well as being unable to understand his ideas, and in the preface to the French version of his Principles (1647) dissociated himself from him in rather violent terms. When one of Regius’s students, Petrus Wassenaer, reacted by publishing a number of theses from chapter 12 of Fundamenta physices, restoring more particularly the passages Regius had suppressed in concession to Descartes, Descartes replied by the Notes Against a Program (1648). When Descartes in turn published the Passions of the Soul (1649) Regius replied by publishing De affectibus animi (“Dissertation on the Passions of the Soul,” 1650). Regius also refused all cooperation with Claude Clerselier when he started to publish Descartes’s correspondence. More particularly he accused him of providing false versions of the texts of Descartes’s letters—to a certain extent that is right, given the fact that Clerselier worked on the draft letters and often combined fragments in a rather unfortunate way. Still, Clerselier seems to have gotten hold of copies of Regius’s letters to Descartes. They are quoted, and sometimes summarized, by Adrien Baillet. So much is clear, the unfavorable picture of Regius that dominates the literature on Descartes should be corrected. Without being an original thinker Regius’s importance for Descartes personally as well as for the diffusion of his ideas has been great.
RENERI, HENRICUS (1593–1639). Reneri was born in Huy (near Liège) and educated in Louvain (Collège du Faucon), presumably to become a priest. His conversion to Calvinism made this obviously impossible. He pursued his studies in Leiden, where he studied theology, but instead of becoming a minister, he earned a living as a private teacher and as a governor in a rich Amsterdam family. In Amsterdam he met Descartes, with whom he became friends and whom he introduced to various Dutch personalities, like David le Leu de Wilhem (1588–1658) and Constantijn Huygens. When in 1632 he was appointed professor of philosophy and rhetoric at the Illustrious School of Deventer, Descartes followed him to work on his Treatise on Light. And when in 1634 Reneri was appointed professor of philosophy in Utrecht, Descartes followed him in 1635. Although there is some evidence that Reneri studied Descartes’s Dioptrics and Meteors with his Utrecht students, there is little reason to call him a Cartesian. In fact, his outlook is rather that of an empirically minded Aristotelian with little interest in metaphysics, if any, who may have learned more from Francis Bacon and Pierre Gassendi than from Descartes. Still, while keeping Descartes at work, he admired him enormously and seems to have created a Cartesian excitement among Utrecht students. At the occasion of his death in 1639 he was commemorated in a funeral oration by his colleague Antonius Aemilius (1589–1660), professor of history. In fact, this became a long eulogy of Descartes, undoubtedly to the surprise of everybody present. For Gysbertus Voetius the exaggerated claims made about Descartes’s philosophy in Aemilius’s speech may have been a reason for tabulating a series of disputations on atheism; indeed, in his eyes, the inevitable disappointment caused by those claims could produce skepticism, which is no more than one step to atheism. Apart from a few disputations Reneri did not publish anything.
REVIUS, JACOBUS (1586–1658). Revius (or Reefsen) was born in Deventer in 1586. He studied philosophy and theology at the universities of Leiden, Franeker, and Saumur. In 1614 he became minister in Deventer. He met Descartes through their common friend Henricus Reneri. In 1641 Revius was appointed dean of the Statencollege (a college for theological bursars of the states of Holland) at Leiden University. A great literary talent, writing fluently in Dutch, French, Latin, and Greek, he supervised the official Dutch translation of the Bible (Statenvertaling, 1637), in particular the Old Testament. His poems are mostly religious, but they also concern the victories of the Dutch army. Like Gysbertus Voetius he believed that theology needs a philosophical framework. It is to that end that he wrote Suarez repurgatus (1643), a Calvinist commentary on Francisco Suárez’s Metaphysical disputations. Revius may have distrusted Descartes from the time that Descartes lived in Deventer (1632–34). It is Revius to whom Descartes, on being questioned about his faith, said: “I have the religion of my king,” and when further questioned, “I have the religion of my wet-nurse.”
But his irritation about the new philosophy turned into exasperation when at the Statencollege he had to bear the company of his deputy dean Adriaan Heereboord, who was an outspoken Cartesian. After incidentally commenting on the theological implications of Descartes’s position in Suarez repurgatus, Revius wanted to devote a whole series of disputations to Cartesian philosophy in 1647. Only a few (on Cartesian doubt and on the Cartesian idea of God) could be held before the administrators (curatores) of Leiden University ordered him to stop and issued a decree in which they forbade professors to mention Descartes’s name and to discuss his opinions. This did not deter Revius from writing a book on Cartesian method (Methodi cartesianae consideration theologica 1648), something that was also forbidden, and from publishing several pamphlets. Johannes Clauberg and Tobias Andreae wrote against him, and Revius replied each time in books that became more and more voluminous. Christoph Wittich’s proposal for reading Scripture in a nonphysical sense also received an answer. Although Revius’s criticism does not lack substance and in many ways is even more articulate than Voetius’s, it had little influence; Revius is now known only as a poet, even in the Netherlands.
ROBERVAL, GILLES PERSONNE DE (1602–75). A French mathematician and natural philosopher, known for his contributions to infinitesimal mathematics and mechanics. Little is known about Roberval’s early years or his education, but he arrived in Paris in 1628 and became active in Marin Mersenne’s circle, gaining such a substantial reputation that Mersenne referred to him as “our geometer” in published works relating the investigations of the group. Appointed professor of philosophy at the Collège de Maître Gervais in 1632, Roberval won the triennial competition for the Ramus chair of the Collège Royal in 1634, a position he would hold until his death. In 1655 he succeeded to the mathematics chair formerly held by Pierre Gassendi, another post he held for the rest of his life. The statutes of the Ramus chair required the incumbent to defend his position every three years in an open competition, with problems set by the incumbent. This contributed to Roberval’s reluctance to publish any of his methods, and as a result his mathematical results were communicated to contemporaries only in correspondence, and often accompanied by allegations of plagiarism. Indeed, the only works he published in his lifetime were his 1636 Traité de méchanique and a 1644 edition and commentary on Aristarchus (Aristarchii Samii de mundi systemate). He was elected to the Académie Royale des Sciences in 1666.
Roberval was a persistent critic of Descartes in both mathematics and natural philosophy. Descartes’s biographer Adrien Baillet suggested that his failure to be included among those who received presentation copies of the Discourse on Method and Essays was the origin of Roberval’s antipathy; although this seems somewhat improbable, the relationship between them was certainly marked by hostility. Roberval belittled Descartes’s Geometry in the course of a controversy that erupted between Descartes and Pierre de Fermat in 1637–38, contributing a piece to the dispute in which he defended Fermat’s methods and summarized points of obscurity and inadequacies in Cartesian geometry and optics (AT, vol. II, pp. 103–15). Even a decade later, Descartes would insist that Roberval “and his sort” offered criticisms and amendments to the Geometry only because “they are not capable of understanding it” (AT, vol. V, p. 142). In natural philosophy Roberval defended the possibility of a vacuum against Descartes’s identification of space with body, critiqued the Cartesian treatment of the laws of motion and impact, as well as objected to Descartes’s account of the center of oscillation of the pendulum.
Roberval’s Traité des indivisibles—first published in 1693 by the Académie Royale des Sciences—is his most important single work, even though it was unpublished in his lifetime. In this systematic treatise, he found areas of figures and arc lengths of curves by treating continuous geometric magnitudes as composed of infinite collections of infinitely small parts. Another technique he employed was to consider curves as traced by a “composition of motions” and then draw tangents or construct arc lengths by analyzing the component motions. His most celebrated application of these methods was to the problem of finding area and tangent to the cycloid—the curve traced by a point on the periphery of a circle as it rolls uniformly across a plane surface. He achieved his results in the mid-1630s and claimed priority for them in a dispute with Evangelista Torricelli, who had undertaken similar investigations and published them. Commenting on Roberval’s treatment of the cycloid, Descartes remarked with characteristic venom that “I don’t see why he made such a fuss over having found something so easy that anyone who knows even a little geometry could not fail to find it if he went looking for it” (AT, vol. II, p. 135).
ROHAULT, JACQUES (1620–72). The foremost proponent of Cartesian natural philosophy in the decades immediately following the death of Descartes, Rohault was best known for his popular 1671 Traité de physique (“Treatise on Physics”), which went through numerous editions and remained a standard textbook in Cartesian natural philosophy well into the 18th century. Born in Amiens to a moderately prosperous merchant family, Rohault’s early education was undertaken at Amiens (probably under the Jesuits), after which he continued his studies at Paris, taking an M.A. degree in 1641. Rohault distinguished himself in mathematics and natural philosophy. He established himself as a private tutor in these subjects, in which capacity he tutored the children of several prominent families as well as the dauphin. In the mid-1650s he began to hold weekly lectures at his house in Paris. These “mercredis de Rohault” did much to popularize Cartesian natural philosophy and brought him to the attention of prominent Cartesians. In 1658 he assisted Claude Clerselier in publishing a reply to certain criticisms of Descartes’s Dioptrics advanced by Pierre de Fermat. At about the same time he won Pierre-Sylvain Régis over to the cause of Cartesianism, and in 1665 Régis accepted Rohault’s invitation to serve as a kind of Cartesian missionary by spreading the doctrine in Toulouse through a series of lectures in the style of Rohault.
By the 1660s Rohault had emerged as the arbiter of Cartesian scientific affairs in Paris. In addition to his public lectures and private tutoring on Cartesian natural philosophy he was an active participant in the intellectual circles of leading natural philosophers. In 1667 he organized the ceremonies marking the return of Descartes’s remains to Paris from Stockholm. His prominence among Cartesians led to political and theological difficulties in his later years. The increasing hostility to Cartesianism in France in the late 1660s, which culminated in the 1671 decree of Louis XIV suppressing anti-Aristotelian teachings at the University of Paris, brought Rohault under suspicion of heresy. In his Entretiens sur la philosophie (“Conversations on Philosophy”), published in 1671, the same year as the Traité de physique, Rohault tried to reconcile Cartesian natural philosophy with Catholic theology by insisting on a strict separation of scientific and religious questions. This attempt met with little success, and at the time of his death in December of 1672 leading authorities in Paris still regarded him as a heretic.
Rohault held that the explanations of natural philosophy could only be probable and he sought to overcome the Cartesians’ reputation for dogmatism by illustrating Cartesian principles through practical experiments. In his Traité de physique he posed as an arbiter between the systems of Descartes and Aristotle, offering Cartesian corpuscular-mechanical explanations for experimental phenomena from pneumatics, magnetism, and other branches of natural philosophy. He thereby introduced Cartesian doctrines as more complete elaborations of traditional Aristotelian teachings and undertook to ground them in experimental practice.
Rohault’s Traité de physique was translated into English by John Clarke and augmented by Samuel Clarke, who had originally annotated and translated the Traité into Latin. First published in English in 1697 as Rohault’s System of Natural Philosophy, it became a standard textbook for generations of English students. As it went through multiple editions, Samuel Clarke increasingly “illustrated” it with “notes taken mostly out of Sr. Isaac Newton’s Philosophy.” Although Clarke’s footnotes often eclipsed the Cartesian text, the work became a monument to the improbable marriage of Cartesian natural philosophy with Newtonian physical theory.
ROSICRUCIANS. A secret brotherhood allegedly founded by Christian Rosencreutz, who it is said, was born in the 14th century and lived for over 100 years. Rosencreutz supposedly traveled in the east, learned magic and cabala, and then returned to Europe to establish the society devoted to the reformation of universal knowledge. Early on Descartes was attracted to the brotherhood and sought out its members. Clearly, the themes of new science that would harmonize all sciences and the dismissal of intellectual authorities such as Aristotle and Galen appealed to Descartes. In 1620 Descartes had mentioned his hope for a new harmonious science: “The sciences are now masked. If the masks were taken off, they would appear in all their beauty. Anyone who would see the linkage of the sciences, would not find them any more difficult to retain in the mind than a series of numbers” (AT, vol. X, p. 215). Descartes had previously penned the following brief description of a proposed treatise he would write under the pseudonym Polybius the Cosmopolitan: “[It] gives the true way of solving all the difficulties of mathematical science; it demonstrates that the human mind cannot achieve anything more with respect to these difficulties. The work is aimed at people who promise to show new miracles in all the sciences, so that it can shake them out of their laziness. . . . The work is offered for a second time to the learned of the world, and particularly to the most celebrated Rosicrucian Brothers in Germany” (AT, vol. X, p. 214). According to Descartes’s biographer, Adrien Baillet, Descartes was not able to find any member of the society, and thus he decided that the whole thing was a fabrication. See also FAULHABER, JOHANNES.
RUBIO, ANTONIO (1548–1615). Rubio entered the Jesuits in 1569, received his doctorate in theology in Mexico, 1577, and taught philosophy and theology there from 1577 to 1599 (after which he returned to Spain). He published commentaries on many works of Aristotle (Logica, 1603, Physica, 1605, De anima, 1611). Descartes remembered him as one of the Jesuit philosophers whose textbooks he read in his youth, along with the Conimbricenses and Franciscus Toletus.
RULES FOR THE DIRECTION OF THE MIND (REGULAE AD DIRECTIONEM INGENII). The Rules for the Direction of the Mind were written somewhere between 1619 and 1625, but never finished. The work should have contained at least 24 rules, each with its own commentary, but that is almost certainly the belated result of a desperate attempt to create unity in what may have been a series of small essays on methodological problems. Internal evidence shows that Descartes frequently abandoned the manuscript; there are many inconsistencies in it, especially in the first 10 rules. Despite this, the Regulae are among Descartes’s most interesting treatises because it is the only one that explicitly deals with the problem of method and with universal mathematics (mathesis universalis). All published and manuscript versions of the text go back to a copy made by Walter von Tschirnhaus after an original in the possession of Claude Clerselier. The work was published for the first time in a Dutch translation in 1684, together with a Dutch version of the Search for Truth. It was published in a Latin version in 1702 (as part of the Opuscula posthuma). Neither goes back to the only other version we know, namely, a copy in the Leibniz Archives.