In the past, experts have disagreed about whether Samuel Clarke accepted the idea that gravity is a power superadded to matter by God. Most scholars now agree that Clarke did not support superaddition. But the argumentation employed by Clarke to reject superaddition has not been studied before in detail. In this paper, I explicate Clarke's argumentation by relating it to an important discussion about the possibility of superadded gravity in the Clarke-Collins correspondence. I examine Clarke's responses to Collins and draw (...) on his other works to reconstruct Clarke's reasons for rejecting superadded gravity. (shrink)