Pierre Gassendi

We look at some interesting and important episodes in the life of early modern Epicureanism, focusing on natural philosophy. We begin with two early moderns who had a great deal to say about ancient Epicureanism: Pierre Gassendi and Ralph Cudworth. Looking at how Gassendi and Cudworth conceived of Epicureanism gives us a sense of what the early moderns considered important in the ancient tradition. It also points us towards three main themes of early modern Epicureanism in natural philosophy, which we (...) then discuss at greater length: atomism, materialism about the mind or soul, and the denial of providence, which was often accompanied by deflationary explanations of religious belief. (shrink)

Pierre Gassendi is often viewed mostly as an antiquarian because of his interest in reconstructing Epicurean philosophy. Admittedly, Gassendi was one of the main actors in the revival of atomism in the seventeenth century, but he was also a supporter of Copernican cosmology, and he proposed a groundbreaking theory of space: not only did he depart from the Aristotelian notion of place, but he even proposed a new ontological conception of space as neither a substance nor an accident. For Gassendi, (...) space was a homogeneous, infinite, three-dimensional entity which could be filled with bodies but was independent of them and could remain void. This new conception of space was elaborated not only as a revival of Epicureanism, or as a foundation for the new science, but also through a re-elaboration of the scholastic notion of imaginary spaces. The aim of this paper is to unravel some of Gassendi’s unacknowledged scholastic sources and explore how Gassendi, a staunch anti-Aristotelian, relied on a reinterpretation of this scholastic notion for his construction of a cosmological system immune to theological criticisms otherwise directed at the Epicurean and Brunian infinitist worldviews. This reinterpretation directly paved the way for a geometrical conception of space. (shrink)

Pierre Gassendi was a major figure in seventeenth-century philosophy whose philosophical and scientific works contributed to shaping Western intellectual identity. Among "new philosophers", he was considered Descartes’ main rival, and he belonged to the first rank of those attempting to carve out an alternative to Aristotelian philosophy. Given the importance of Gassendi for the history of science and philosophy, it is surprising to see that he has been largely ignored in the Anglophone world. This collection of essays constitutes the first (...) book on Gassendi that comprehensively covers his biography, bibliography, and all aspects of his philosophy. The book is divided into four parts. It begins with a brief sketch of the intellectual world of seventeenth-century France, Gassendi’s early attacks on Aristotle, and a bibliographical essay on early-modern publications of Gassendi’s writings. Part II explores Gassendi’s contributions to logic, natural philosophy, and astronomy and cosmology. Part III addresses Gassendi as a humanist and participant in seventeenth-century philosophical and scientific debates, including his advocacy of Epicurean philosophy and his relation to the sceptical tradition. The fourth and final part involves a brief discussion of the reception of Gassendi’s thought, including the paraphrases of his works published in France and England. This book is an essential resource for scholars and upper-level students of early modern philosophy, intellectual history, and the history of science who want to get acquainted with Pierre Gassendi as a major philosopher and intellectual figure of the early modern period. (shrink)

Gassendi and Hobbes knew each other, and their approaches to philosophy often seem similar. They both criticized the Cartesian epistemology of clear and distinct perception. Gassendi engaged at length with skepticism, and also rejected the Aristotelian notion of scientia, arguing instead for a probabilistic view that shows us how we can move on in the absence of certain and evident knowledge. Hobbes, in contrast, retained the notion of scientia, which is the best sort of knowledge and involves causal explanation. He (...) thought, however, that this sort of knowledge was only available in geometry and political philosophy. (shrink)

Pierre Gassend, or, as he is widely known, Gassendi, was a French materialist philosopher, physicist, astronomer, theologian and Catholic priest. He was the son of Antoine Gassend2 and Françoise Fabry, and was born on January 22nd in 1592 in Champtercier, a village of Provence, and died on October 24th in 1655 in Paris. He received his first education in the cities Digne and Riez and by the age of twelve he began his initiation to Catholicism. He belonged to the Franciscan (...) Order.3 The continuation of his formal education was supported by the Catholic Church as an aspect of his preparation for priesthood.4 He studied Aristotelian philosophy and Catholic theology for the next eight years at the College of Aix in Provence. Pierre Gassendi is typically remembered for introducing the ancient atomic philosophy of Epicurus in 17th century European thought. Gassendi aspired to articulate a new philosophy of nature, in order to replace Aristotelianism, which had been prominent in the context of scholastic thought for centuries, and had constituted the foundation of physics as well as moral philosophy. Gassendi was a priest and an ardent follower of the new scientific methodology of empiricism and of experimental trial. He devoted his life’s work to bringing together the Christian doctrines with the principles of the new science. Gassendi, along with Francis Bacon and Descartes, was one of the most significant figures who exerted influence on the development of science and mechanistic philosophy in the second half of the 17th century, especially in England. His views can be seen throughout the summary of Francois Bernier, a work that emphasizes the atomic views, and materialistic tendencies, of philosophical thought. Gassendi’s adapted Epicurean philosophy spread to Britain with Opera Omnia and the Abregé of Bernier, and also due to Walter Charleton, who published a modified English translation of parts of Animadversiones in 1648. There was also a group of enthusiastic empiricists, who belonged to the circle of Newcastle, as well as a small Epicurean club whose members were among others Kenelm Digby and Nathaniel Highmore. All of the above saw a deep and pervasive influence of Gassendi’s views on British thought. His influence is seen in the writings of major thinkers, such as Boyle, Locke, Hobbes, Newton, Hume, Reid, and in the early works of Leibniz. The multi-dimensional personality of Gassendi, as a pastor, humanist and physical philosopher, accords with a moral and the physical universe in which the Creator God of the Christian faith holds a prominent role. He has been characterized by many researchers as the founder of mechanical philosophy, and as the successor of humanistic historiography. He was a defender of atomic theory, which was flourishing in the second half of 17th century, and also inspired Locke, one of the major proponents of moral theory. Gassendi’s contribution in moral philosophy is unexceptionable; his notions of freedom and pleasure formed the basis of the liberal tradition of late 17th and 18th centuries. (shrink)

Richard Baxter, one of the most famous Puritans of the seventeenth century, is generally known as a writer of practical and devotional literature. But he also excelled in knowledge of medieval and early modern scholastic theology, and was conversant with a wide variety of seventeenth-century philosophies. Baxter was among the early English polemicists to write against the mechanical philosophy of René Descartes and Pierre Gassendi in the years immediately following the establishment of the Royal Society. At the same time, he (...) was friends with Robert Boyle and Matthew Hale, corresponded with Joseph Glanvill, and engaged in philosophical controversy with Henry More. In this book, David Sytsma presents a chronological and thematic account of Baxter's relation to the people and concepts involved in the rise of mechanical philosophy in late-seventeenth-century England. -/- Drawing on largely unexamined works, including Baxter's Methodus Theologiae Christianae (1681) and manuscript treatises and correspondence, Sytsma discusses Baxter's response to mechanical philosophers on the nature of substance, laws of motion, the soul, and ethics. Analysis of these topics is framed by a consideration of the growth of Christian Epicureanism in England, Baxter's overall approach to reason and philosophy, and his attempt to understand creation as an analogical reflection of God's power, wisdom, and goodness, understood as vestigia Trinitatis. Baxter's views on reason, analogical knowledge of God, and vestigia Trinitatis draw on medieval precedents and directly inform a largely hostile, though partially accommodating, response to mechanical philosophy. (shrink)

ABSTRACT. In his Letters on the motion impressed by a moving mover, Gassendi offers a theory of the motion of composite bodies that closely follows Galileo’s. Elsewhere, he describes the motion of individual atoms in very different terms: individual atoms are always in motion, even when the body that contains them is at rest; atomic motion is discontinuous although the motion of composite bodies is at least apparently continuous; and atomic motion is grounded in an intrinsic vis motrix, motive power, (...) while composite bodies simply persist in their state of motion or rest in the absence of outside intereference. Gassendi does not make much effort to explain how his accounts of atomic and composite motion fit together, and it’s difficult to see how they could possible be integrated. My goal is to explain, given this difficulty, why he accepted both the Galilean theory of the motion of composite bodies and the Epicurean theory of atomic motion. (shrink)

Contrary to most modern interpretations, in the early modern period, history was an indispensable resource for many philosophers. The different uses of history by Bacon, Gassendi, Locke, and Hume are explored to establish the role of history as a resource in early-modern philosophy.

This paper discusses how Gassendi and other 17th century atomists treated the distinction between primary and secondary qualities.

It is often suggested that certain forms of early modern philosophy are naturalistic. Although I have some sympathy with this description, I argue that applying the category of naturalism to early modern philosophy is not useful. There is another category that does most of the work we want the category of naturalism to do ? one that, unlike naturalism, was actually used by early moderns.

Writing about the history of science and the history of philosophy involves assumptions about the role of context and about the relationships between past and present ideas. Some historians emphasize the context, concentrating on the intellectual, personal, and social factors that affect the way earlier thinkers have approached their subject. Analytic philosophers take a critical approach, considering the logic and merit of the arguments of past thinkers almost as though they are engaging in contemporary debates. Some philosophers use the ideas (...) of historical figures to support their own philosophical agendas. Scholarly studies of the French natural philosopher Pierre Gassendi (1592–1655) exemplify many of these .. (shrink)

The article regards the transformation of friendship in Hobbes’s work. From simple acceptance of the Aristotelian definition in The Whole Art of Rhetoric, Hobbes passes in the Elements to a dual approach. On one hand, he goes so far as to reaffirm the natural sociability of man solely through friendship but, on the other, he subordinates the whole question of passions to the new concept of power, which involves the redefinition of friendship as an "Instrumentall power". In Leviathan this connection (...) between "power", "honour" and "friendship" becomes tighter and tighter. Did Gassendi influence Hobbes’s shift, which was fully developed in Leviathan? Security and need are the key words in the Epicurean doctrine of friendship, and also Epicurus did not endorse the thesis of human natural sociability. The analogies with the Hobbesian doctrine are impressive . However, Gassendi was well aware of the objections raised against the too utilitarian nature of Epicurean friendship. His strategy consisted in moralizing this kind of affection and promoting a revival of Aristotle’s theory. With its insistence on the need for security and utility, it is Hobbes’s approach, therefore, that is closer to the true Epicurean doctrine of friendship. By contrast, he reacts against its apolitical character. Whereas for Epicurus and Gassendi the aim of friendship is essentially a "defense" within the context of individual ataraxia, for Hobbes friendship is a "power" that can bring about real and stable benefits only through the social contract and within a political dimension. (shrink)

This article documents the general tendency of seventeenth-century natural philosophers, irrespective of whether they were atomists or anti-atomists, to regard space, time and matter as magnitudes having the same internal composition. It examines the way in which authors such as Fromondus, Basson, Sennert, Arriaga, Galileo, Magnen, Descartes, Gassendi, Charleton as well as the young Newton motivated their belief in the isomorphism of space, time and matter, and how this belief reflected on their views concerning the relation between geometry and physics. (...) Special attention is paid to the fact that most of the authors mentioned above regarded rarefaction and condensation, on the one hand, and acceleration and deceleration, on the other hand, as analogous phenomena, which consequently had to be explained in similar terms. (shrink)

This article analyzes Galileo's mathematization of motion, focusing in particular on his use of geometrical diagrams. It argues that Galileo regarded his diagrams of acceleration not just as a complement to his mathematical demonstrations, but as a powerful heuristic tool. Galileo probably abandoned the wrong assumption of the proportionality between the degree of velocity and the space traversed in accelerated motion when he realized that it was impossible, on the basis of that hypothesis, to build a diagram of the law (...) of fall. The article also shows how Galileo's discussion of the paradoxes of infinity in the First Day of the Two New Sciences is meant to provide a visual solution to problems linked to the theory of acceleration presented in Day Three of the work. Finally, it explores the reasons why Cavalieri and Gassendi, although endorsing Galileo's law of free fall, replaced Galileo's diagrams of acceleration with alternative ones. (shrink)

This thesis provides a new analysis of early contributions to the development of the theory of absolute time—the notion that time exists independently of the presence or actions of material bodies and has no material cause. Though popularly attributed to Newton, I argue that this conception of time first appeared in medieval philosophy, as a solution to a peculiar theological problem generated by a widespread misrepresentation of Aristotle. I trace the subsequent evolution of the theory of absolute time through to (...) the seventeenth-century, and argue that Newton, if anything, retreats from a full endorsement of the doctrine. (shrink)

Ultimamente bastante atençáo vem sendo dispensada ao estudo do ceticismo moderado na modernidade. O famoso historiador da filosofia Richard Popkin, em sua História do Ceticismo de Erasmo a Espinosa , cunhou a denominaçáo de ceticismo epistemológico para qualificar os membros desta corrente e nela inseriu os filósofos setecentistas Gassendi e Mersenne, considerando-os seus principais representantes. Além disso, no século XVIII temos o denominado ceticismo mitigado de Hume, que chamou a atençáo dos filósofos modernos para definir os limites do ceticismo. Este (...) artigo procura contribuir para o estudo do ceticismo moderado na modernidade, mostrando náo só que Hume, Mersenne e Gassendi podem fazer parte do assim chamado ceticismo epistemológico ou mitigado, mas também que há certos elementos comuns em suas filosofias destinados a mitigar os argumentos dos céticos de seu tempo. (shrink)

Pierre Gassendi (b. 1592, d. 1655) was a French philosopher, scientific chronicler, observer, and experimentalist, scholar of ancient texts and debates, and active participant in contemporary deliberations of the first half of the seventeenth century. His significance in early modern thought has in recent years been rediscovered and explored, towards a better understanding of the dawn of modern empiricism, the mechanical philosophy, and relations of modern philosophy to ancient and medieval discussions. Through an arch-empiricism—tempered by adherence to key elements of (...) Church doctrine—Gassendi views metaphysics as a realm for speculation grounded in the possibility of empirical confirmation, logic as a psychologistic and probabilistic enterprise, knowledge of the external world as built on and subject to sensory-based evidence, and ethics in quasi-hedonist, possibly quantifiable terms. His philosophy is a constant review of other sources, a thorough consideration of the landscape into which his own empiricism fits and represents an alternative to contrasting claims, past and present. Other hallmarks of his thought include an atomist matter theory, explorations and defenses of the new physics, objections to the Meditations, and refutations of contemporary Aristotelians and mystical thinkers. His presentation of an empiricism, atomism, and new cosmology in historical and philosophical context greatly advanced the community of scholarship in his day, and represents a then-new model of research and exposition. (shrink)

Aucune méthode d'hypothèse et de raisonnement hypothétique en science ne peut être examinée dc façon critique sans que soit résolue au préalable la question de ce qui sert d'hypothèse. D'un point de vue très général, des éléments très différents peuvent servir à constituer la partie hypothétique ou conjecturale de la science. Du temps de Gassendi, il était possible de recourir à des entités hypothétiques tels les tourbillons cartésiens, à de généralisations idéalisées de phénomènes telle la loi de la chute libre, (...) à des élaborations conjecturales comme l'image céleste de Ptolémée, à des modèles explicatifs et synthétiques comme la description par Harvey de la circulation sanguine ou à de modèles précurseurs comme celui de Kepler (orbites planétaires). Tous ces éléments de nature différente ont au moins un point commun : nous les acceptons comme tels avec la promesse de pouvoir justifier leur utilisation, plus tard, d'une façon ou d'une autre. La difficulté de cette acceptation préliminaire, selon une conception toute classique, réside dans le paradoxe qui consiste à profiter des avantages - de nature explicative, déductive ou illustrative, pour n'en citer que quelque-uns - offerts par l'emploi de tels éléments hypothétiques, même si nous manquons de preuves satisfaisantes à leur sujet, et cela pour approfondir notre compréhension de phénomènes pour lesquels nous disposons réellement de preuves. (shrink)

This is about the tension between Epicurean and Galilean accounts of motion in Gassendi. For my more recent thoughts on this, see http://philpapers.org/rec/LOLCEG.

After a spate of monographs on Pierre Gassendi in the mid-1990s, the scholarly discussion of this most difficult French philosopher has largely been confined to the pages of scholarly journals. Except for Sylie Taussig's fine translation of Gassendi's Latin letters into French, and an issue of Dix-septième siècle devoted to the thinker, no major book-length study has appeared. Antonia LoLordo fills this gap in Pierre Gassendi and the Birth of Early Modern Philosophy. Her aim is "defamiliarizing the early modern philosophic (...) landscape" by introducing Gassendi as a major player in a diverse topography of thought. In her analysis, LoLordo articulates and critiques the philosophic content of Gassendi's various works, as well as challenging the interpretations of some of his modern exegetes, most notably, O. R. Bloch and Margaret J. Osler.LoLordo focuses on Gassendi's natural philosophy, epistemology, and ontology. Her contention that Gassendi "was a central figure in seventeenth-century philosophy" will come as no surprise to those familiar with the course of early modern philosophy. LoLordo systematically treats Gassendi's major and minor works, especially his early anti. (shrink)

The accepted view that Gassendi's ethics is a Christianized form of Epicureanism is incomplete: there is extensive and direct influence of Aristotle's works on the key concepts of Gassendi's ethics, while Epicurean ethics is itself largely informed by Aristotle's views. In the first part of this paper, the notion of freedom as choice informed by rational judgment is examined, and the foundation of Gassendi's intellectualist view of freedom is established in Aristotle's notion of prohairesis. In the second part, the nature (...) of happiness is examined, as well as the relationship between happiness and pleasure, and the contemplative as well as active components of happiness. The third part examines the significance of ethics as an ongoing activity of discernment and regulation of desires: the development of a "second nature" through habitual practice of virtues. The paper concludes with a brief consideration of Aristotle's influence on Gassendi's political philosophy. (shrink)

An overview of the influence of Lucretius poem On the Nature of Things (De Rerum Natura) on the renaissance and scientific revolution of the seventeenth century, and an examination of its continuing influence over physical atomism in the nineteenth and twentieth centuries.

Introduction: mathematization and the language of nature -- Realists and nominalists : language and mathematics before the scientific revolution -- Ontology recapitulates epistemology : Gassendi, epicurean atomism, and nominalism -- British empiricism, nominalism, and constructivism -- Three mathematicians : constructivist epistemology and the new mathematical methods -- Conclusion: mathematization and the nature of language.

Peter G. Sobol - Pierre Gassendi's Philosophy and Science: Atomism for Empiricists - Journal of the History of Philosophy 45:1 Journal of the History of Philosophy 45.1 161-162 Muse Search Journals This Journal Contents Reviewed by Peter G. Sobol Mcfarland, Wisconsin Saul Fisher. Pierre Gassendi's Philosophy and Science: Atomism for Empiricists. Brill's Studies in Intellectual History 131. Leiden-Boston: Brill, 2005. Pp. xxviii + 436. Cloth, $172.50. In 1971, Richard S. Westfall described Pierre Gassendi as "the original scissors and paste man": (...) an irrepressibly eclectic compiler whose Syntagma Philosophicum was published only after his death "when the author was finally beyond the possibility of adding and patching." Westfall here echoes Voltaire and Alexandre Koyré who, as quoted in Saul Fisher's.. (shrink)

Argues that Descartes mistook the sense of 'motion' intended by Aristotle in the latter's definition of life as the capacity for self-motion. Descartes' arguments against Aristotelian soul-as-life-principle consequently commit the 'straw man' fallacy.

Generation and heredity theories before early modern mechanist accounts might be faulted for numerous deficits. One might cite in this regard the failure to even attempt to explain how the inheritance of traits could occur, given what is known about the generation of new individuals. On the other hand, it would be hard to allow this as a true failure against the backdrop of a generation theory that poses form, and not matter, as the key to understanding the emergence of (...) new structures in the offspring of two organisms. Hence the signal contribution of the mechanist accounts in this sphere was simply the suggestion that theories of generation and heredity might look to matter and its behavior in order to explain how new individuals are created and retain or discard features of the individuals whence they sprung. Among these accounts, one early important set of views was presented by Pierre Gassendi, eventually as a full-blown atomist conjecture but even beforehand, and early on, as a thoroughgoing materialist theory. Gassendi's materialist mechanism for the transmission of traits is imperfect (and by the common sense of our day, implausible), not always or exclusively deployed in generation, and not clearly the physical bearer of information, as conformity to a materialist model would suggest. Nonetheless, his proposed mechanism represents a valuable attempt to provide an account of inheritance phenomena in materialist and ultimately atomist terms and rooted in an account of generation. (shrink)

This book offers a comprehensive treatment of the philosophical system of the seventeenth-century philosopher Pierre Gassendi. Gassendi's importance is widely recognized and is essential for understanding early modern philosophers and scientists such as Locke, Leibniz and Newton. Offering a systematic overview of his contributions, LoLordo situates Gassendi's views within the context of sixteenth- and early seventeenth-century natural philosophy as represented by a variety of intellectual traditions, including scholastic Aristotelianism, Renaissance Neo-Platonism, and the emerging mechanical philosophy. LoLordo's work will be essential (...) reading for historians of early modern philosophy and science. (shrink)

This look at Gassendi’s philosophy and science illuminates his contributions to early modern thought and to the broader history of philosophy of science. Two keys to his thought are his novel picture of acquiring and judging empirical belief, and his liberal account of criteria for counting empirical beliefs as parts of warranted physical theories. By viewing his philosophical and scientific pursuits as part of one and the same project, Gassendi’s arguments on behalf of atomism can be fruitfully explained as licensed (...) by his empiricism. (shrink)

: In the concluding pages of his Epistolae duae de motu impresso a motore translato (1642), Pierre Gassendi provides a brief summary of the explanation of the tides found in Galileo's Dialogue over the Two Chief World Systems (1632). A comparison between the two texts reveals, however, that Gassendi surreptitiously modifies Galileo's theory in some crucial points in the vain hope of rendering it more compatible with the observed phenomena. But why did Gassendi not acknowledge his departures from the Galilean (...) model? The present article argues that cautiousness was just one of the reasons that stopped the French priest from turning Galileo's theory into his own theory. He was probably also aware of the fact that Kepler's model of planetary motion, which he endorsed in the Epistolae, could not be reconciled with Galileo's explanation of the tides. In the postumously published Syntagma philosophicum (1658), Gassendi tried to mend this major inconsistency by arguing that Galileo's theory of the tides not only remained valid, but became even more coherent, if one attributed to the Earth an elliptic orbit. But given that in the Syntagma Gassendi officially adhered to the Tychonic system, his effort to reconcile Kepler and Galileo, while already unconvincing by itself, appears completely futile. (shrink)

In his accounts of plant and animal generation Pierre Gassendi offers a mechanist story of how organisms create offspring to whom they pass on their traits. Development of the new organism is directed by a material “soul” or animula bearing ontogenetic information. Where reproduction is sexual, two sets of material semina and corresponding animulae meet and jointly determine the division, differentiation, and development of matter in the new organism. The determination of inherited traits requires a means of combining or choosing (...) among each parent's contributions, and towards this end, Gassendi outlines the nature of competition and dominance among animulae. Unlike his fellow mechanists, Gassendi can extend his mechanism to his heredity account, because his proposed vehicle for ontogenetic transmission is material. That proposal in turn relies on his atomist hypothesis. The relative uniformity of atoms allows animulae to operate equivalently across different modes of generation, spontaneous or otherwise. Further, his molecular model of atomic structures allows a material means of storing ontogenetic information received from the souls of parent organisms. These accounts—flawed and sketchy—unsurprisingly fail to specify how hereditary information might be borne physically, and in any case do not meet Gassendi's own empiricist standards. Yet this generation theory with pretensions to a materialist mechanism establishes Gassendi's firm commitment to a unity of the sciences through an atomist ontology that underlies all physical phenomena, including the organic. (shrink)

Pierre Gassendi was a major factor in the revival of Epicureanism in early modern philosophy, not only through his contribution to the restoration and criticism of Epicurean texts, but also by his adaptation of Epicurean ideas in his own philosophy, which was itself influential on such important figures of early modern philosophy as Hobbes, Locke, Newton, and Boyle (to name just a few). Despite his vigorous defense of certain Epicurean ideas and ancient atomism, Gassendi goes to great lengths to differentiate (...) his philosophy from Epicureanism on certain key points. In this paper I argue that those key points on which Gassendi rejects and and criticizes the Epicurean view, such as the immortality of the soul and divine creation of the cosmos, are central not only to Epicureanism, but also to Gassendi's own philosophy. In order to see Gassendi's philosophy for what it is, and understand its role in the history of natural theology, we need accept and understand better why he rejected the central theses of Epicureanism. (shrink)

The 17th century's new science and new philosophy was roughly equally divided between Cartesians and Gassendists. Scholars agree that understanding Gassendi's metaphysics, epistemology and scientific method is crucial for understanding the development of modern philosophy, as Gassendis version of Epicureanism provides a third strand of influence on modern philosophy paralleling Cartesianism and scholasticism. Despite this, Gassendi is rather little understood today. I look at Gassendi in the context of his Objections and Counter-Objections to the Meditations, along with Descartes' Replies. This (...) context provides an explicit display of the opposition between two main strands of the new philosophy. I argue---contra a popular characterization of Gassendi's thought as primarily skeptical or even wholly unsystematic---that Gassendi's objections derive from a systematic psychology and cannot be well understood without a grasp of this psychology. ;I begin with a central methodological question in the dispute, the status of clear and distinct perception and what this tells us about proper procedure. This disagreement has it source in competing accounts of the cognitive faculties. Hence I go on to develop an account of Gassendi's theory of the cognitive faculties, and in particular perception, the acquisition of ideas, and reasoning. I then examine Gassendi's initially rather puzzling objections to the cogito, which act as a test-case for my interpretation of Gassendi's theory of cognition. I end with the dispute over the mind-body relationship. Gassendi objects that Descartes has failed to give any more than a nominal definition of the mind, having failed to make intelligible the modes of the mind in terms of its essence. Gassendi, in contrast, seeks an account of the operations of the mind in terms of the micro-level structure of the parts of the brain, and understands this micro-level structure as the genuine essence of the mind. This objection provides an excellent case for examining how Descartes and Gassendi's rival psychologies influenced two very different notions of scientific method. (shrink)