From James Nickel & Adam Etinson, Human Rights, at the SEP:
Attributing human rights to god’s commands may give them a secure status at the metaphysical level, but in a very diverse world it does not make them practically secure. Billions of people today do not believe in the god of Christianity, Islam, and Judaism. If people do not believe in god, or in the sort of god that prescribes rights, then if you want to base human rights on theological beliefs you must persuade these people to accept a rights-supporting theological view. This is likely to be even harder than persuading them of human rights. Legal enactment at the national and international levels provides a far more secure status for practical purposes.The claim that legal enactment is a more secure foundation for the position that human rights exist "in a very diverse world" than divine commands seems a common view in some circles, but it also seems straightforwardly false, and it's difficult to see what conceivable argument for it could even be plausible. Legal enactment requires recognized legal authority; there is no legal authority at the national and international levels -- at all -- that has universal or even practically universal recognition as an authority capable of being a source of human rights nor is this surprising, since human rights are (as the authors recognize) generally taken to be at least mostly universal, and therefore seem to require an authority with at least mostly universal scope for the human race, which gives us a very limited set of candidates. Many, many more people believe in the existence of a God who can endow human beings with rights than accept the authority of any international or national agency in existence. Christians and Muslims alone make up more than half the population of the earth, and it's not clear you could get even half the population of the earth to accept that the United Nations actually has the authority to provide a "secure status for practical purposes" for human rights existing.
What's more, the proverb, "What's good for the gander is good for the goose", comes to mind here: If there are many people who believe that human rights exist because of God's commands and not any human agency -- and there undoubtedly are, and they are many -- the argument given here against the divine command option applies a fortiori to the legal enactment opposition; if people do not believe that international agencies, or the sort of international agencies that exist, can prescribe human rights, "then if you want to base human rights on" legal enactment, "you must persuade these people to accept a rights-supporting" view of international law that can actually ground human rights. Nickel & Etinson seem to assume that it's obvious that because legal agencies can recognize the existence of human rights that legal agencies can account for their existence; but there are many views on which the latter is not possible. The concern for a "diverse world" here seems to be fake, or at least based on a failure to think through the argument. Yes, it's true that many people have views that make a divine-command-based view impossible; it is at least as obviously true that many people have views that make a nation-and-international-law view a non-starter. The actual tendency of the argument, if we accepted it, is to the position that there is no way to explain the existence of human rights, because if theism doesn't unite a sufficiently large and diverse portion of the planet to count, nothing available does. No legal authority is as widely respected and deferred-to by as large and diverse a population as divine authority is, and it's not even close.
Part of what is happening, of course, is that the diversity of theistic views about God is being treated as a strike against theistic grounding, while the diversity of juridical views about legal and political agencies is being ignored. But the two cases are in fact parallel. Theism in this context merely has to be adequate to establish that human rights exist -- that is compatible with widely different views of God's nature and acts, and also with considerable disagreement about which things in particular we should consider to be divinely endowed human rights. The details can be worked out by argument -- just exactly as they have to be on the legal-enactment view, which assumes that people who do not at all agree on the nature and scope of authority of national and international legal powers are nonetheless able to come to adequate agreement "for practical purposes" on human rights.
Of course, we should not accept the argument at all. If you are really concerned with "a diverse world", all views have to be taken seriously; if you are really interested in truth, it does not matter that there are people who are not persuaded, but only on what is the right view; if you are really interested in persuasion, you have to go with the view that actually persuades more people; if you are really interested in practical security of human rights, you should work with the views on which people actually base their practical reasoning. On all of these grounds, one should reject an argument like this, even if we assume (which we should not) that what explains the existence of human rights must be some sort of positive enactment like a divine command or legal enactment at the national or international level.
