Edgeworth's original mathematical formalization of utilitarianism as presented in his works of 1877–81 illustrates an intriguing phase in the mutually intertwined history of economics and utilitarianism. In this article I analyse Edgeworth's motivations and point to its interesting implications. In particular, it is pointed out that the starting point of Edgeworth's project had little to do with the field of economics, but formed part of an attempt to present utilitarianism in the most scientific way possible; an attempt made in the (...) context of intensive dispute between the three opposing camps in the field of ethics at the time. Nevertheless, the project concluded with the monograph Mathematical Psychics (1881) that embodied an original relationship between economics and utilitarianism. (shrink)