It is hard to deny that things might easily have been diﬀerent.2 A fervent Catholic in Belfast may reﬂect that she might easily have been a Protestant had she been brought up a few streets away. An urbane modern European who regards human sacriﬁce as inconceivably abhorrent might well have regarded it as quite the done thing had he been born in ancient Mesopotamia or Peru. How disturbed should we be by this apparent contingency in our deepest beliefs and attitudes? This will be the question I shall mostly be concerned with in this chapter. The way we answer that question has crucial implications for the ancient philosophical project of trying to determine how one should live. Bernard Williams was very pessimistic about the viability of that project, at least in anything like its traditional ambitious form; and the eloquent articulation of the grounds for such pessimism – centring on the problem of contingency – was among his most potent philosophical legacies. For those among us who harbour the hope that the ancient project is still one we can reasonably address, it is a matter of some importance to see if we can ﬁnd a way of defusing that pessimism.