PHYSICAL AND LITERARY. 133 



from this confideration, that, if body had 

 an a(5lual tendency to fall down, it could 

 not at the fame time refift the downward 

 motion by its inertia. Which reafoning 

 plainly fuppofes,that there is a real adivc 

 refiftance arifing from inertia. And m-^ 

 deed, though he exprefsly intends to deny 

 the fmalleft activity in matter, yet he e-' 

 very where fpeaks of inertia, as a conatus 

 or tendency efTential to matter, by which 

 it makes a violent oppolition to the pow- 

 er of gravity, and other adive powers. 

 This being a queftion of the utmofl im- 

 portance, it may not be amifs to offer an 

 amendment upon that argument, which 

 will free it from any inconfiftency, and 

 place it on its true bottom, on which a - 

 lone it can (land its ground. To prove 

 then that gravity does not proceed from 

 any internal adive force of any kind, ei- 

 ther in the earth or fuch bodies as fall to- 

 wards it, it is only necefTary to afTume 

 one axiom, that no fubftance can adively 

 tend to move to two oppofite fides, at the 

 fame time. It is eafy to conceive that a 



body 



