Pierre Gassendi 1592-1655

(Born Pierre Gassend) French philosopher, astronomer, historian, and priest.

Pierre Gassendi's place in the history of science and philosophy is still being written and revised. Gassendi was well known to his contemporaries in his native France and in England as a formidable scholar, the foremost proponent of the Epicurean revival, and an estimable astronomer. However, Gassendi's dense Latin prose, his wearisome prolixity, and his apparent (and perhaps temporary) loss to René Descartes of one of the great battles of Western philosophy condemned him to obscurity from the eighteenth century to the late twentieth century. As the importance of atomism and neo-Epicureanism to the development of modern science becomes clearer, however, Gassendi's stature amongst such notable seventeenth-century thinkers as Thomas Hobbes, John Locke, Robert Boyle, Isaac Newton, and even his adversary Descartes, has risen. A leading exponent of French empiricism, Gassendi advocated a skepticism which held that knowledge could be received only through the senses; experiment and observation, rather than pure ratiocination, were the requirements of his natural philosophy. Gassendi's materialism and connection to Epicurus opened him to groundless charges of libertinism and atheism; ironically, the focus of the French priest's life's work was to reconcile Epicureanism with Christianity.

Biographical Information

Pierre Gassend was born January 22, 1592, in the small village of Champtercier, in the Provencal region of France. (Gassendi is the Italianized version, the final “i” a mark of honor added due to his scholarly reputation.) His schooling began under his uncle Thomas Fabry, until at the age of seven he was sent to the larger town of Digne to study Latin and arithmetic. At 14 he returned to Champtercier for two years before going to the University of Aix, where he studied philosophy and theology. In 1614 he received his doctorate in theology from the University of Avignon, and in 1616 he celebrated his first Catholic Mass as an ordained priest. It was also in 1616 that Gassendi met his great mentor, Nicolas-Claude Fabri de Peiresc, with whom he maintained a close friendship and extensive correspondence until Peiresc's death in 1637. In 1617 Gassendi took the Chair of Philosophy at the University of Aix. During his six years teaching philosophy (primarily Aristotelian), Gassendi also taught his students his own arguments contrary to the Aristotelian doctrines that dominated early seventeenth-century thought. When, in 1622, Jesuits took over the University and Gassendi was compelled to leave teaching, friends encouraged him to make public his lectures, which constitute his first work, Book I of Exercitationes Paradoxicae adversus Aristoteleos, published in 1624 (planned later books were not completed).

Gassendi traveled to Paris in 1625, beginning a friendship with Père Marin Mersenne, who would later be instrumental in the great debates between Gassendi and Descartes. During this year, Gassendi also made connections with Elie Diodati and Galileo as he pursued his interest in observational astronomy, an interest that helped provide the foundation for his philosophical skepticism, which held that knowledge apprehended through the senses was uncertain at best. Meanwhile, his attacks on Aristotle finding only a mixed reception, Gassendi turned his attention to Epicurus, beginning an explication of his philosophy and a short Life of Epicurus for its preface. He proceeded slowly with this work, continuing to maintain his interest in astronomy as well. Interrupted by serious illness and the death of his mentor, Peiresc, Gassendi abandoned the work in 1637 for four years. Instead, he wrote his Life of Peiresc (1641) and, at the request of Mersenne, reviewed Descartes' Meditations, preparing a set of Objections (1641). Descartes' Responses were contemptuous, and Gassendi replied with Instantiae (first circulated in Paris in 1642), creating a public battle between the two philosophers. Gassendi also maintained at this time a heated debate with the astrologer Jean-Baptiste Morin, whose insistence that the earth was the center of the universe spurred Gassendi to develop further the views of Copernicus and Galileo.

In 1645 Gassendi returned to teaching as the Chair of Astronomy at the College Royal de France in Paris, during which time he published his coursework as Institutio astronomica (1647). He was compelled to leave due to failing health, returning to Provence in 1648, a year after his De vita et moribus Epicuri libri octo (Life of Epicurus) finally appeared. Gassendi had not approved of this publication, which barely scratched the surface of what Gassendi had hoped to achieve in reviving Epicurus. Encouraged by friends, Gassendi released much of his later work on Epicurus attached as an appendix to his translation of the Tenth Book of Diogenes Laertius' De Clarorum Philosophorum Vitis.In 1649 his massive Animadversiones in Decimum Librum Diogenes Laertii was published, but despite its positive reception, Gassendi was again displeased with its over-hasty release. The Animadversiones is the only work not reproduced in its original form in Gassendi's Opera omnia.

In 1653 Gassendi returned to Paris, telling a friend in a letter that in leaving Provence he had been delivered “from the jaws of Hell,” so ill had he been feeling. While in Paris Gassendi busied himself with a new edition of his Animadversiones, which would be published posthumously as his Syntagma philosophicum. He also wrote biographies of several astronomers, including Copernicus and Tycho Brahe, and published works on coinage, music, and the history of the diocese of Digne. Beginning in August 1654, however, Gassendi suffered from more severe and more frequent bouts of illness; he was not able to fulfill his plans for his Syntagma philosophicum, which his editors completed in 1658. He died in Paris on October 24, 1655. Prior to his death, Gassendi had selected those texts he wanted included in his complete works and arranged for their publication in Lyon; they were published as his Opera omnia in 1658.

Major Works

Gassendi's chief importance in the history of science and philosophy has been in his conflict with Descartes and, especially, in his revival of Epicurean philosophy. His first work, Exercitationes Paradoxicae adversus Aristoteleos, demonstrates the frustration with the state of seventeenth-century philosophy that would characterize much of his work. To many of his contemporaries, his attack on Aristotelian philosophy was tantamount to an attack on the seventeenth-century worldview, but he was not yet prepared to offer an alternative, as he eventually would in his exposition of Epicurus. Gassendi did, however, promote a positive skepticism that offers intellectual freedom and advocates experimental knowledge, while denying the possibility of complete and certain knowledge. That possibility was a major part of Gassendi's debate with Descartes, who held in his Meditations that things could be known purely via the mind, while Gassendi maintained that knowledge could be obtained only through the senses and was thus necessarily incomplete and uncertain. Throughout Gassendi's Objections, Descartes' Replies, and Gassendi's lengthy Instantiae, the two refer to each other as “Mind” and “Flesh” as an indication of their contempt for the other's position, and as a reflection of the core difference in their epistemology. Yet although Gassendi was best known through the twentieth century for his skirmish with the man who became one of the most important philosophers in the history of Western thought, during his lifetime battling with Descartes was not one of his major concerns.

Throughout the later part of his career especially, vindicating and “Christianizing” Epicureanism as a viable philosophy was the most prominent theme in his work. In particular, Gassendi needed to counter the popular belief that Epicureanism could be equated with libertinism and atheism in order to achieve his goal, and this was part of the work of his De Vita et Moribus Epicuri. Begun in 1626 as an extension of his attack on the Aristotelians, Gassendi revised it significantly to make it an account of Epicurean philosophy and a careful defense of Epicurus from the misrepresentations of the Stoics, early Christian writers, and others who accused him of sensualism or impiety. Gassendi initially intended for De Vita et Moribus to precede a more thorough exposition of Epicurean philosophy, but his original plans were never realized. He published much of his subsequent work on Epicurus with Animadversiones in Decimum Librum Diogenis Laertii, in an appendix titled Philosophiae Epicuri Syntagma, but with his last major work, Syntagma Philosophicum, Gassendi shifted his focus from explicating the doctrines of Epicurus to expounding his own philosophy. Divided into three sections—Logic, Physics, and Ethics—and preceded by a short book on the nature of philosophy, the Syntagma promotes the atomism, skepticism, and materialism Gassendi found in Epicurus and develops it in a seventeenth-century context. The Syntagma was published as the first two volumes of the massive six-volume Opera omnia in 1658, not fully completed by Gassendi, but still offering the most fully realized explication of his neo-Epicurean philosophy.

Critical Reception

Even Descartes, who could not contain his frustration with what he considered Gassendi's inability to comprehend his Meditations, had great respect for Gassendi as a scholar. Gassendi's reputation in England was considerable; along with Descartes, he was considered a model for the New Science practiced by the Royal Society. The question of his influence on English thought has been complicated by the vexing practice held by early modern authors of not citing their sources; however, modern studies have convincingly demonstrated the indebtedness of Boyle, Newton, and Locke to Gassendi's work. Olivier Bloch and Richard Kroll, among other modern critics, have endeavored to promote Gassendi's importance to English neo-Epicureanism in both scientific and social circles. In particular, Locke's relationship to Gassendi has been the topic of long-standing critical debate. Kroll suggests that Gassendi was merely one influence among many, while Fred S. and Emily Michael argue that Gassendi's theory of ideas was clearly the foundation for Locke's Essay Concerning Human Understanding. Gassendi's alleged libertinism has also attracted the attention of scholars; Richard H. Popkin distinguishes Gassendi's skepticism from the charges of dissolution, while Lisa T. Sarasohn suggests that Gassendi's emphasis on pleasure was a part of the voluntarism that distinguished him from his fellow materialist Thomas Hobbes. The great battle between Cartesian certainty and Gassendist skepticism remains a major focus of the scholarship: Thomas M. Lennon, among others, suggests that Gassendi has long been judged unfairly as a result of Descartes' scorn.