The Problem of Moral Luck

How much of what we are morally responsible for is actually within our control? This question, posed with philosophical precision by Thomas Nagel and Bernard Williams in a pair of papers published in 1976, goes by the name of moral luck — and it is more uncomfortable than it initially appears.

The problem arises because our intuitions about moral responsibility seem to require that we hold people accountable only for what they could have done otherwise, and yet in practice we judge people differently based on factors entirely outside their control. Two drivers, both equally careless, are judged very differently if one of them happens to hit a child who runs into the road. The carelessness is identical. The outcomes are different. And our moral judgements track the outcomes, not merely the carelessness.

Nagel distinguished several varieties of moral luck: resultant luck (the luck in how things turn out), circumstantial luck (the luck in the situations one faces), constitutive luck (the luck in who one is — one's temperament, inclinations, capacities), and causal luck (the luck in how one is determined by antecedent events). Each challenges the intuition that moral desert is grounded in freely chosen action.

The responses to this problem range from compatibilist attempts to show that moral responsibility does not require the kind of control the problem assumes, to revisionist accounts that accept the challenge and propose scaling back the domain of moral judgement accordingly. None has proved entirely satisfying.

What moral luck most usefully does, perhaps, is not dissolve moral responsibility but complicate it — generating a kind of humility about the ease with which we judge others. The person we judge may not be in a relevantly different moral position from us. They may simply have been unluckier. And recognising this is not a reason to abandon evaluation but a reason to conduct it with less confidence than we usually do.