The Open Source Initiative's definition of "open source" focuses exclusively on a list of approved licenses: Only software using one of the approved licenses counts as open source. This narrow definition is concerned only with the shape of business contracts designed to de-risk corporate involvement in FLOSS. But we all know that what makes open source amazing is not the licensing, but the community. Open source is defined in practice by its community-driven, collaborative mode of software development. So it should be no surprise that the best open source projects have a laser focus on building thriving communities. Nor should it surprise us that many projects using OSI-approved licenses appear open source in name only. Ethics is the study of how to get along with others. This makes it the perfect tool for understanding how to build thriving, successful communities. In this talk, I argue that the Ethical Source Definition actually provides a more compelling definition of "open source" than the OSD. It better accords with community usage of the term, capturing what makes open source unique and successful.