GASSENDI, PIERRE. - French philosopher, b. 22 Jan. 1592 at Champtercier (Digne), d. in Paris on 24 Oct. 1655. A canon and preacher, he taught theology (1613) and philosophy (1616) at Aix and subsequently, until his death, mathematics in Paris.
His first work (1624) was directed against Aristotle and Scholastic philosophy (Exercitationes paradoxicae adversus Aristotelem). In his later works he concerned himself with atomistic doctrine, in a far from brilliant and cumbersome attempt to renew Epicureanism: the Syntagma philosophiae Epicuri (1649) is an exposition of the Greek philosopher’s doctrine, whereas the Syntagma philosophicum, his principal work, published posthumously (1658), may be regarded as his philosophical summa; it is divided into logic, physics, and ethics, with a special section devoted to method. Yet more than for these prolix and cumbersome writings, G. is still known today for his objections to Descartes’s Meditations and for the polemical work (in reply to Descartes) Disquisition metaphysicae, seu dubitations et instantiae adversus Renati Curitzii metaphysicum et responsa (1644). G. is, above all, an episode in the controversy against Cartesian science, a page in the debate between the empirical and deductive approaches. An admirer of Galilei, whose influence he felt, he grasped the importance of the laws of dynamics; as a revaluator of atomism, he drew attention to a theory that was suited to the new science and opposed to Descartes’s geometrical mechanism. Moreover, since atomic theory entailed the admission of the void, he came to uphold philosophically (against the Aristotelians and Descartes) what Torricelli and Pascal had demonstrated experimentally.
From a more strictly speculative point of view, G. is of little interest. His logic has a marked nominalist and empiricist tone, while his physics follows Epicurean atomism, reconsidered in accordance with the theories of the age and above all with the concern to correct those of its assertions most sharply at variance with religion. Thus, for example, he admits creation ex nihilo (atoms, ungenerated and incorruptible from the natural point of view, were created by God and can be annihilated by God), as well as the fact that the movement of atoms is caused by God, ruler and orderer of the universe, Providence. Under Galilei’s influence he maintains that not motion, but the impulse to motion, is constant; and, with Telesio, that all atoms possess a sensitivity of their own (different from that of animals and men). The principle of sensitivity and life is the soul of the world (a Stoic and also Neoplatonic doctrine). Thus, in G.’s elaboration, Epicurean physics loses its materialist and mechanistic structure. But rather than a critical reconsideration, it is a compromise or, if one wishes, a contaminatio of materialism and spiritualism. His doctrine of the soul is likewise a compromise: besides the soul made of most subtle matter
there is another in man, the immaterial and immortal “intellect,” created by God and infused into the body (Physica, sect. III, I, III, cap. 3). He himself perceived the inconsistency and tried in vain to resolve it: just as man is said to be one, although consisting of body and soul, so the soul is one, although there are two souls in man (cf. ibid., I, IX, cap. 2).