Modern finance – its theory and practice – is devoid of ethical considerations. Or so it is commonly understood. Friedman’s and Robbins’ distinction between normative and positive science and the qualification of economics as a positive discipline ‘independent of any particular ethical position or normative judgements’ fostered the image of a theory devoid of ethical foundation. So did the definition of efficiency in the neoclassical economic model, where the best economic system is defined as the one that generates the greatest output for a given quantity of resources, implying that efficiency does not incorporate distributive considerations. Beyond theory, data on financial transactions point to their capacity to move enormous sums of money in a way that increases polarization of wealth across and within countries. Finally, corporate scandals and episodes of financial speculation that reveals illicit firms’ and individuals’ behaviour have triggered resentment against un-ethical financial practices.

Departing from these ideas, the article argues that modern finance is geared around ethical considerations: its theory, neoclassical finance, arose out of the precise purpose of finding a fair system for resource allocation. The problem is instead a definitional one: what do we mean by ethics in finance? Even the examples provided above clearly point to different concepts or aspects of an ethical discourse: fair distribution, legality, legitimacy. In the search for a focus of analysis to address ethics in finance, the article proposes to look at the moment of the exchange. Though it might sound like a reactionary move – after all, one of the main criticisms moved to neoclassical finance is that it reduces finance to the moment of exchange – this choice proves particularly productive to bring the analysis back to the individual participating in or bearing the costs of financial transactions.