The idea of human rights consists of two parts: the premise or claim that every human being is sacred (inviolable, etc.), and the further claim that because every human being is sacred (and given all other relevant information), certain choices should be made and certain other choices rejected; in particular, certain things ought not to be done to any human being and certain other things ought to be done for every human being. One fundamental challenge to the idea of human rights addresses the first part of the idea; it contests the claim that every human being is sacred. Another fundamental challenge, the one with which this article is principally concerned, addresses the second part of the idea. According to this latter challenge, whether or not every human being is sacred — and, so, even if every human being is sacred — there are no things that ought not to be done (not even any things that conditionally rather than unconditionally ought not to be done) to any human being and no things that ought to be done (not even any things that conditionally rather than unconditionally ought to be done) for every human being. That is, no putatively “human” right is truly a human right: no such right is the right of every human being; in that sense, no such right — no such “ought” or “ought not”–is truly universal. Before addressing this challenge, which shall be referred to as the relativist challenge to the idea of human rights, a comment on the other fundamental challenge, which contests the claim that every human being is sacred, is in order.