References to Malthus are increasingly evident in narratives of agricultural trends in development discourse at the end of the twentieth century. This article addresses the long roots of Malthusian thinking in formulating public policy, that can be traced across from Malthus's own ideas and to subsequent construction of neo-Malthusianisms in the nineteenth and twentieth centuries. It deploys the distinction between two approaches to statistical data collection that emerge in Malthus's own time: an ‘open’ system that collects data to identify trends, and a ‘closed’ system that uses data to prove an existing model. The article uses these distinctions in order to demonstrate opposing tendencies in policy-making in both England and India, with particular reference to Indian agriculture. It shows how radical thinking about data collection as an inductive line of enquiry lost out to a deductive approach that regarded data on Indian agriculture as doomed, because of its ‘unimproved’ condition, and highlights three moments where opposing tendencies were important. The article concludes that this turn in thinking about food, land, and people continues to persist in agricultural policy-making in international development circles into the present.