In this article, we document how, in the public arena, British readers of the first edition of Isaac Newton's Philosophiae naturalis principia mathematica (1687) tried to make sense of the relation between gravity, matter, and divine and natural causation—an issue on which Newton had remained entirely silent in the first edition of the Principia. We show that readers attached new meanings to the Principia so that parts of it migrated to a different intellectual debate. It will be shown that one (...) particular result Newton obtained in the Principia, namely the rejection of a vacuum in Corollary 3 to Proposition 6 in Book 3, was the most important locus in debates on the relation between gravity, matter, and causation. (shrink)