Public funding for science is increasingly coming under attack. This article explores the normative force of these charges, and the arguments that are available to counter them. It examines two justifications of state support for science: Vannevar Bush’s vision of the universal material benefits of scientists pursuing basic research and John Rawls’s liberal justification of science funding as a voluntary public good. It argues that both accounts neglect the important political impact of scientific research and its status as the source of knowledge for the modern state. The article then traces the implications of the political role of science for the appropriate forms of democratic input into funding decisions.