INDUCTIVE EPOCH OF NEWTON. 183 



That all such forces, cosmical and terrestrial, 

 were the same single force, and that this was 

 nothing more than the insensible attraction which 

 subsists between one stone and another, was a con- 

 ception equally bold and grand; and would have 

 been an incomprehensible thought, if the views 

 which we have already explained had not prepared 

 the mind for it. But the preceding steps having 

 disclosed, between all the bodies of the universe, 

 forces of the same kind as those which produce the 

 weight of bodies at the earth, and, therefore, such 

 as exist in every particle of terrestrial matter; it 

 became an obvious question, whether such forces 

 did not also belong to all particles of planetary 

 matter, and whether this was not, in fact, the whole 

 account of the forces of the solar system. But, 

 supposing this conjecture to be thus suggested, how 

 formidable, on first appearance at least, was the 

 undertaking of verifying it! For if this be so, every 

 finite mass of matter exerts forces which are the 

 result of the infinitely numerous forces of its parti- 

 cles, these forces acting in different directions. It 

 does not appear, at first sight, that the law by which 

 the force is related to the distance, will be the same 

 for the particles as it is for the masses; and, in 

 reality, it is not so, except in special cases. And, 

 again, in the instance of any effect produced by the 

 force of a body, how are we to know whether the 

 force resides in the whole mass as a unit, or in the 

 separate particles? We may reason, as Newton 



