Agreement between moral theories › Start with reasons rather than a verdict

Imagine two people who agree that a promise should be kept. One points to the friend's reliance on it. The other asks what would happen if people generally abandoned commitments whenever something more attractive appeared. Agreement about the action is clear; agreement about its justification is less clear. A shared verdict can emerge from different reasons, and the difference may matter when the next case is harder.

Derek Parfit's On What Matters asks how far some influential approaches to morality can converge. Its first two volumes appeared in 2011; a third followed in 2017. The central convergence project concerns revised versions of Kantian ethics, rule consequentialism and contractualism. Parfit tries to show that their strongest formulations can support the same principles. Understanding that proposal requires more than checking whether three familiar theories happen to approve the same action.

The distinction changes how we read the book. Parfit is developing arguments for particular formulations, then arguments connecting them. He is not reporting that existing disagreements have disappeared. This chapter explains the proposed connections, the role of objective reasons, and the tests a reader should apply before accepting the resulting Triple Theory.

A reason, in the normative sense relevant here, is a consideration that counts in favor of an attitude or action. Someone's pain might count in favor of helping them. That differs from an explanation of why a person acted: fear of embarrassment could explain someone's assistance even when the other person's need supplies the better justification. The distinction lets us ask whether an action has good reasons behind it without assuming that its actual motive was good.

Parfit defends an objective account of reasons. On his view, what we have reason to do is not fixed simply by what we happen to want. Desires themselves can be assessed. A desire to avoid severe suffering can have a justification that an arbitrary desire to suffer on a particular day lacks. Describing a preference, even accurately, does not yet settle whether there is a reason to act on it.

This is an argument within the book, rather than a starting point every reader must accept. The question is whether facts about the objects of our desires can give us reasons independently of those desires. Parfit's opposition to desire-based accounts concerns the grounds of normative reasons; it does not require denying that desires influence behavior or that learning what someone wants matters in deliberation.

Consider a hypothetical person who refuses a painless way to avoid agony because they currently have no desire to avoid it. The example separates wanting relief from having reason to want relief. An objectivist can say that the suffering supplies a reason even when the desire is absent. Someone defending a desire-based view will need to explain which desires count and why. The example presents the dispute; describing it does not resolve every version of that dispute.

The objectivity question also differs from the convergence question. We could agree that there are objective moral truths while disagreeing about which theory describes them. Conversely, agreement among several theories would not establish objectivity without further argument. Parfit pursues both projects, but success in one cannot simply be assumed to establish the other.