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22 ESSAYS ann OBSERVATIONS 
continuance of that quantity of motion which 
is once given to a body. If the intervention 
of fpirit be rejected as above, there is but an- 
other hypothefis to recur to, which is, That 
inanimate matter is endued with a power to 
preferve itfelf in motion, as well as animated 
matter is, without any other difference, but 
that the former having no will or feeling, acts 
blindly and invariably by an eftablifhed law. 
It has no fpontaneous motion, becaufe it is has 
no will. Neither has it in every circum{tance 
a power of beginning motion; but, when 
once fetin motion, it has a power given it by 
the Author of nature to continue it felf in mo- 
tion. And this is a Jaw which regards all 
matter without exception. 
Anp this power being once eftablifhed, it 
remains only to be made out, that it is of a 
different kind from that which refiftsa change 
from reft to motion, and from any degree of 
motion to a greater. The thing is obvious ; 
for, as caufes are beft dftinguifhed by their 
effets, the caufe cannot be the fame of two 
effects diametrically oppofite. w/z. preferving 
a body in motion, and oppofing motion. It 
may ferve to clear this matter, if we attend 
to the diftingtion betwixt impulfe and refift- 
ance. 
