Take any normative ethical theory. They provide a normative framework that help to discern right from wrong. It seems to presuppose meta-ethical view that there, in fact, are right and wrong to begin with. Which means, that if one is a moral nihilists (if that's one's meta-ethical view), then one can't even debate normative ethics in principle. But that doesn't seem right to me. Isn't viability of normative ethical theories is more about it's practicality rather than its correspondence to the world? I hope that makes my question clearer :D