Morality makes claims on us—we ought to act in certain ways. But why should we accept those claims? What gives morality authority? Answers range from divine command and natural law to social contract and the inherent value of conscious beings. Justifying morality's authority is distinct from determining its content.
Ask yourself: why should you be moral when it costs you? If you answer 'because it's right,' reflect on what makes something right. Different answers point to different sources of moral authority.
From your study of normativity and moral language, you know that moral claims are normative — they do not merely describe how people behave but prescribe how they *ought* to behave. This raises an immediate and deep question: what makes that "ought" binding? When someone says "you ought not lie," they are doing more than expressing a preference or predicting your behavior — they are claiming a kind of authority over your action. This topic asks: where does that authority come from, and can it be justified?
The oldest answer is divine command theory: moral obligations are authoritative because they originate from God's commands. This view has the advantage of grounding morality in something maximally authoritative — God's will. But it faces a problem posed by Plato in the *Euthyphro*: is something morally good because God commands it, or does God command it because it is morally good? If the former, morality seems arbitrary (God could have commanded cruelty and that would have made cruelty good). If the latter, then moral goodness is independent of God's commands, and the divine command theory doesn't actually explain the source of moral authority — it just relocates it. Natural law theory is a related view that grounds morality in the rational order of nature: what is morally required is what accords with the natural ends of human beings. This attempts to make moral authority objective without making it arbitrary.
Social contract theories offer a secular alternative. On this view, moral authority derives from agreement — either an actual agreement among people (Hobbes, Locke) or a hypothetical agreement that rational agents would reach under fair conditions (Rawls). The appeal is that this grounds moral authority in reasons agents can themselves endorse: you are bound by moral rules you would have agreed to if you were reasoning well. The limitation is explaining why hypothetical agreements bind us: if I didn't actually agree, why does what I would have agreed to create real obligations for me? Kantian constructivism responds by grounding authority in the requirements of practical reason itself — the categorical imperative derives moral authority from what any fully rational agent must will. Authority on this view is not external (God, society) but internal: it is what you commit yourself to in virtue of being a rational agent at all.
Expressivism and error theory offer more skeptical perspectives. Expressivists (like Blackburn and Gibbard) argue that moral claims do not state facts at all — they express attitudes or make prescriptions. On this view, moral authority is not a matter of discovering binding obligations but of the social and emotional pressures that make moral norms stick. Error theorists (like Mackie) go further: moral claims purport to describe objective facts, but no such facts exist, so all moral claims are technically false. These views do not necessarily lead to nihilism — expressivists argue that moral practice can be fully justified even without objective moral facts — but they do require reconceiving what "moral authority" means. The question for any account is ultimately the same: when morality makes a claim on you, what gives that claim the power to demand your compliance even when compliance is costly?
Topics in reflective domains aren't scored by quiz answers. Read, reflect, and mark when you've thought it through.