Abstract
The non-identity problem is usually considered in the forward-looking direction but a version of it also applies to the past, due to the fact that even minor historical changes would have affected the whole subsequent sequence of births, dramatically changing who comes to exist next. This simple point is routinely overlooked by familiar attitudes and evaluative judgments about the past, even those of sophisticated historians. I shall argue, however, that it means that when we feel sadness about some historical tragedy, or think of one possible course of history as better than another, these judgments and attitudes can be understood in terms of two opposing perspectives on the past: an impersonal standpoint concerned only with how much value each course of history contains, and a person-centred standpoint concerned with harms and benefits to the people who had actually existed. In this paper, I will set out these radically different visions of what matters in history and point out some of their surprising implications.