to revive the ancient systems which have been mentioned above (p. 29). Its superior influence depends on the fact that, in the conception of atoms, it offered exact inquiry a most useful point of attachment. The conflict between the Gassendists and the Cartesians, which at first was a bitter one, centered, as far as physics was concerned, around the value of the atomic hypothesis as contrasted with the corpuscular and vortex theory which Descartes had opposed to it. It soon became apparent, however, that these two thinkers followed along essentially the same lines in the philosophy of nature, sharply as they were opposed in their noëtical principles. Descartes' doctrine of body is conceived from an entirely materialistic standpoint, his anthropology, indeed, going further than the principles of his system would allow. Gassendi, on the other hand, recognizes an immaterial, immortal reason, traces the origin of the world, its marvelous arrangement, and the beginning of motion back to God, and, since the Bible so teaches, believes the earth to be at rest,—holding that, for this reason, the decision must be given in favor of Tycho Brahé and against Copernicus, although the hypothesis of the latter affords the simpler and, scientifically, the more probable explanation. Both thinkers rejoice in their agreement with the dogmas of the Church, only that with Descartes it came unsought in the natural progress of his thought, while Gassendi held to it in contradiction to his system. It is the more surprising that Gassendi's works escaped being put upon the Index, a fate which overtook those of Descartes in 1663.
As modern thought derives its mechanical temper equally from both these sources, and the natural science of the day has appropriated the corpuscles of Descartes under the name of molecules, as well as the atoms of Gassendi, though not without considerable modification in both conceptions (Lange, vol. i. p. 269), so we find attempts at mediation at an early period. While Père Mersenne (1588-1648), who was well versed in physics, sought an indecisive middle course between these two philosophers, the English chemist, Robert Boyle, effected a successful synthesis of both. The son of Richard Boyle, Earl of Cork, he was born at Lismore in 1626, lived in literary retirement at
