156 THE THEORY OF GRAVITATION. 



consequences of the different intensities which might be given to such 

 or such properties, has chosen in each case that intensity most proper 

 to attain the desired result and has precisely determined the conse- 

 quences without any preliminary trial. 



XXVII. 



All other conceivable objections are founded on certain regularities or 

 irregularities of detail which have not been minutely set forth, but gra- 

 tuitously assumed, and which, in consequence, ought not seriously to be 

 taken into account. Or, in the second place, such objections may be 

 founded on the tenets of some metaphysical sect. Before responding to 

 such objections I pray these metaphysicists to first agree among them- 

 selves. Or, finally, they address themselves to the imagination rather 

 than to the understanding. Thus some may be shocked at what in this 

 system is extreme, strange, or extraordinary — as if it was after our 

 gross and limited measures that the subtlety and grandeur of Nature 

 must be evaluated ! As if a confused repugnance sufficed to condemn 

 a theory which depends neither on taste nor sentiment! Or as if one 

 ought to follow servilely the beaten track, even in researches where 

 no success has ever come to those who have followed it ! 



XXVIII. 



If one is satisfied with the exact agreement of this system with 

 physical astronomy and with terrestrial phenomena, he ought not to 

 distrust it, as if this apparent conformity were the effect of the artful- 

 ness with which I have adjusted matters or as if other systems also 

 might be rectified so as to agree throughout with the phenomena 

 should a hand more skillful take the same pains to accommodate them 

 to each other. 



I have not added to the atoms sung by Lucretius any feature 

 directed solely toward the explanation of the great laws discovered by 

 the Moderns. But, on the contrary, I have merely divested the motion 

 of these atoms of an arbitrary feature (the nearly perfect parallelism) 

 by which Epicurus had disfigured the unrestricted motion assumed by 

 Democritus. That was a motion so simple that it would appear as if 

 its inventor had proposed it with no other end but the most absolute 

 simplicity, unconcerned that it might in no way explain real phenom- 

 ena, but rather, perhaps, contradict them; so that it is impossible that 

 any system can equal this in simplicity. 



I would even have had no need to advise myself of this correction, 

 in reading the poem of Lucretius, if I had been instructed beforehand 

 in the system of Leucippus and Democritus as I was long after this 

 reading. 



Finally, the explanations which I have offered ought not to be 

 regarded as in any respect modifications of this system of atoms, for it 

 would be impossible not to fall upon these explanations in seeking to 

 follow out the necessary consequences of this system. 



