His native air having produced a considerable amelioration in his strength, Gassendi was able to return to Paris in 1653, and the next year he published Tychonis Brahaei, Copernici, Peurbachii, &c.
a work which was not confined to the biography of these great men, but also coutained a brief sketch of ancient and modern astronomy down to his own day. The resumption of his literary labours quickly brought on a return of his former disorder, and be died on the 14th of October 1655, in the sixty-third year of his age. His valuable collection of books and his astronomical and philosophical apparatus wore purchased by the Emperor Ferdinand IlL, and deposited iu the Imperial Library at Vienna.
The philosophical reserve and moderation of Gassendi have led Bayle to designate him as a sceptic, which however, to judge at least from his writings, is little in accordance with the spirit of his philosophy; for although ho often complains of the weakness of human reason, which even in the sphere of physical investigations is constantly at fault, and therefore admits the insufficiency of his own discoveries to satisfy either himself or others, this circumstance, while It rendered him patient in controversy and unwilling to enforce his own conclusions upon others, only proves at most that his dogmatism was not as one-sided and immoderate as that of other dogmatists, and that even while he insisted upon the possibility of establishing positive results, ho was yet sceptical enough to doubt the finality of his own positions.
By the philosophical cast of his mind and the variety of his acquire ments, as well as by the amiable moderation of his oharacter, Gassendi was one of the brightest ornaments of his age. Boyle has justly styled him the greatest philosopher among scholars, and the greatest scholar among philosophers. He may have been surpassed by some of his contemporaries in particular departments of inquiry, as, for instance, by Dea Cartes, in the higher branches of mathematics, yet none came near to him in reach and universality of genius. Varied as was his erudition, it did not overpower the clearness of his intellect, the too common result of great learning ; on the contrary, his works are distinguished for the perspicuous arrangement of the ideas, the justice of the reasoning, the acuteness of the criticism, and the pre eminent lucidness of the style and diction.
The works of Gassendi were collected by Montmort and Sorbibre, 6 vole. foL, Lyon, 1658, and by Averrani, 6 vols. fol., Firenze, 1728. There is a life of Gassendi by SorbRre, prefixed to the collected works, and one by Bougercl, Paris, 1737.