In addition, the
exact phrase: "Natural Born Citizen" was defined in the Law of Nations (i.e. Natural Law). The framers were clearly not only aware of the work, but read and referred to it during the Con Con itself (see
Madison's notes). That, unquestionably, is the definition they were relying on. No need to come up with a definition, it was already defined word for word. Furthermore, it prevented (as much as possible) "foreign entanglements" suggested by Jay in his letter to Washington (which, predates the requirement showing up in their drafts).
