THE NEWTONIAN LUCRETIUS. 1 



By M. Le Sage. 



[Read by M. Prevost at a meeting of the Berlin Academy in 1082.] 



" In all branches of knowledge the earliest systems are too limited, too narrow, 

 too timid ; and it would even seem that the prize of truth is only won by a certain 

 audacity of reason." — Fontenelle, in eulogy of Cassini. 



THE AIM OF THIS MEMOIR. 



I propose to show that if the earliest 2 Epicureans had possessed as 

 just ideas on cosmography as those of several of their contemporaries, 

 which they neglected, and but a portion of the knowledge of geometry 

 which had then been attained, they would in all probability have easily 

 discovered the laws of universal gravitation and its mechanical cause. 

 Laws, whose discovery and demonstration are the greatest glory of the 

 mightiest genius that has ever lived; and cause, whose comprehension 

 has long been the object of ambition of the greatest physicists, and is 

 now the stumbling block of their successors. Such things, for example, 

 as the famous Kepler's laws — discovered scarcely two centuries ago, and 

 founded in part upon gratuitous conjectures and in part upon tedious 

 gropings — would have been nothing but special inevitable corollaries of 

 the general knowledge which the ancient philosophers could easily draw 

 from nature's own mechanism. This conclusion is entirely applicable 

 to Galileo's laws on falling bodies, whose discovery has been still slower 

 and more contested. Moreover, the experiments by which this discovery 

 was established were so crude that they left the way open to interpre- 

 tations which rendered them equally compatible with several other 

 hypotheses, 3 which were in fact urged against him. On the other hand, 



1 Translated by C. G. Abbot from Nouveaux Memoires de L'Acadc'mie Royale des 

 Sciences et Belles-Lettres. Anne"e, MDCLXXXII. A Berlin, MDCLXXXIV, pp. 

 404-427. 



- 1 say only the earliest ; for after a system has survived several centuries it leads 

 men to the one or the other of two extremes. Some reject everything pertaining to 

 the system disdainfully, while others, on the contrary, embrace reverently all its 

 traditions, without offering to make the least correction. It is this latter faction 

 who have adopted the atoms of Epicurus, Lucretius, Gassendi, and all the intervening 

 Epicureans. * * . * 



3 One of these hypotheses was that the total time being as the arc of a certain 

 circle, the total distance fallen through was as the versed sine of this arc. Now if 

 the magnitude of this circle had been better chosen, I do not see how one would be 

 able to refute this hypothesis, starting from the simple phenomena. 



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