The debate over whether or not economics is value-free has focused on the fact-value distinction: “is” does not imply “ought.” This paper approaches the role of ethics in economics from a Thomistic perspective, focusing not on the content of economic analysis, but on the actions taken by economic researchers. Positive economics, when it satisfies Aristotle's definition of technique, enjoys a certain autonomy from ethics, an autonomy limited by a technique's dependence for guidance and justification on ethical reflection. The modern isolation of technique from ultimate ends entails the risk of mistaking the proximate ends of economics for ultimate ends, especially when applying economic methods in new ways or to new social phenomena.