4 M^L\M<\:'S\, Dere/opjncnt of the Atomic TJieory. 



absence of ponderable matter, space is occupied by ether, 

 " the celestial matter ; " in short, that " we have no means 

 of producing an ether-vacuum." 



A more conventional theory is due to the revival, by 

 Gassend, of the Epicurean philosophy. His interest in 

 this philosophy was such that for twenty years he devoted 

 himself to the study of Epicurus, and Lucretius the 

 Epicurean." Gassend sought to connect the atomic 

 theory with both physical and ethical problems, for those 

 were the days when natural and moral philosophy were 

 studied by the same persons. He brought out three 

 books on the subject, between the years 1647 and 1649, 

 one of which, the " Syntagma Philosophiae Epicuri," was 

 well known to Boyle. 



Boyle learnt of the work through his friend Samuel 

 Hartlib, who wrote to him, in a letter dated London, 

 May 9th, 164S : "Your worthy friend and mine, Mr. Gas- 

 send, is reasonable well, and hath printed a book of the 

 life and manners oi Epiaii us, since your going from here. 

 He hath now in the press at Lyons the philosophy of 

 Epicurus, in which, I believe, we shall have much of his 

 own philosophy, which doubtless will be an excellent 

 work." ^^ 



There was then, as there is still, a tendency to regard 

 Descartes and Gassend as opponents of one another on 

 the principles of the atomic theory. Boyle mentions some 

 "learned men as more favouring the Epicurean, and 

 others (though but a few) being more inclinable to the 

 Cartesian opinions." However, in one of his essays, he 

 advises Pyrophilus to read the "learned Gassendus,\{\s 



" For a study of the Lucretian philosophy, see "Lucretius, Epicurean 

 and Poet," 2 vols., by John Masson. Chap, i, vol. 2, is devoted to Gassend, 

 of whom it gives a most interesting account. 



'" Boyle's Works, ed. by Hirc'n, vol. 5, p. 257, 1744. 



