Drawing on Michel Foucault’s analytics of governmentality, this paper addresses the fiscal theory of the classical political economy of the 18th century and that of the post-Ricardian economics in which the neoclassical mindset developed in the context of the transformation of liberalism. While the general approach places the classical and neoclassical distinction in the last quarter of the 19th century, Keynes’s classification of the post-Ricardo economics as ‘classical’ to distinguish his theory makes the classical-neoclassical distinction in fiscal theory ambiguous. Clarification of the meaning of this distinction defined by Keynes can be achieved through the logic of liberal government as well as its ethical philosophy and politics. Since the most concrete form of the liberal governmental reason and problematics, which have been transformed since the 18th century, is observed through public finances, it is possible to evaluate the transition of the fiscal theory from classical to neoclassical, from there to Keynes and then to neoliberalism in light of this sort of analysis. Foucault’s history and analytics of governmentality provide a framework, method, and set of tools through which we can engage with the history and theory of public finance from a different perspective