  Though memory is not the metaphysical ground of personal identity, it provides first-personal evidence of it. Reid notes that the evidence we use to make judgments about our own pasts is different from the evidence we use to make judgments about other people and their pasts (Essays 266). Memory justifies first-personal reports about one’s own witnessed past, while judgments of qualitative similarity justify third-personal statements about the identities of other persons. I know that I was present at my wedding because I remember being there. I know that the man I live with was at my wedding because he looks like the man I married.