“The past is not another country; it is another life. The texture of daily living is different now than in the past, more different the further back we look, until we find people whose experiences created a psychology we might find baffling or rude. Many details that once made up the daily round are lost to us because people considered them too trivial to write down. Knowing the past means knowing what people carried in their pockets, what they did with their sewage, where their dogs slept. Those details may seem unimportant, but what they convey is not.”