Abstract
This paper is part of a larger project defending of the foundations of microeconomics against recent criticisms by philosophers. Here, we undermine one source of these criticisms, arising from philosophers' disappointment with the performance of microeconomic tools, in particular game theory, when these are applied to normative decision theory. Hollis and Sugden have recently articulated such disappointment in a sophisticated way, and have argued on the basis of it that the economic conception of rationality is inadequate. We argue, however, that their claim rests upon a misunderstanding of the concept of a game as it is used in microeconomics.