PHYSICAL AND LITERARY. 17 
«« always perfeveres in its ftate of reft, or of “ 
“‘ uniform motion, in aright line, ’till, by 
“© {ome external influence, it be made to 
«< change its {tate.” This property is han- 
' dled by writers without any degree of accu- 
tracy. The bulk of them refolve it into the 
inertnefs and patflive nature. of matter ; and 
confider the prefent ftate of a piece of mat- 
ter, whether of motion or of reft, to be an 
effect, which, once produced, muft conti- 
nue toexift as it is, “till it be changed or de- 
{troyed by the operation of a new caufe. But, 
as this conception of the matter is liable to 
ftrong objections, which {hall by and by be 
mentioned, the moft rational writers admit 
of a power in matter to preferve itfelf in its 
prefent ftate; butthen, confidering the per- 
feverence in reft and in motion, to be effects 
of the fame kind, they, without making a- 
ny diftinGtion, attribute both to the fame 
power or caufe. . 
I cannor fubfcribe to either of thefe noti- 
ons. It is obvious to me, that the mere ne- 
_ gation of a caufe, tho it may account for the 
Se fa a er 
continuance of a body at reft, as it may ac- 
count for its preferving the fame figure or 
Colour; yet can never account for the re- 
4°) fiftance 
