In 2010 Reinhart and Rogoff published “Growth in a Time of Debt”, a wildly successful macro-economics paper. The conclusions made in that paper turned out to be based on a mistaken analysis of the available data. My intention here is to explain how they went wrong, without cleaving to mere worries about how to look at the data. I cover a number of different issues, and arrive at an account of the conceptual details of the paper, which emphasises the “fragility” of the “systematic relationship” the paper purports to have discovered. I discuss the question of “induction” and argue that the paper goes beyond induction anyway, which leads me to conclusions about how causation is built into economic theory, and how such building in requires more careful attention than the authors of “Growth in a Time of Debt” (Reinhart, Rogoff 2010), and their critics, attempted.