Many prominent proponents of Old and New Natural Law morally condemn sexual acts between people of the same sex because those acts are incapable of reproduction; they each offer a distinct set of supporting reasons. While some New Natural Law philosophers have begun to distance themselves from this moral condemnation, there are not many similarly ameliorative efforts within Old Natural Law. I argue for the bold conclusion that Old Natural Law philosophers can accept the basic premises of Old Natural Law (...) without also being committed to morally condemning sexual activity between people of the same sex. I develop an argument from analogy that shows how we can draw metaphysically distinct sub‐categories based on someone's capacity to experience the unitive goods of sex. This unitive capacity constitutes the sub‐category and provides a distinct principle for evaluating how members of that sub‐category (X) act as members of that sub‐category, rather than as acting as defective members of another category (Y). Even though my argument is ‘internal’ to Old Natural Law, I conclude by showing how these conclusions can also address some of the objections to same‐sex sex in New Natural Law. (shrink)