So what we share with brothers and sisters is, in every sense, our DNA: not just elements of the real, physical double helix, but also the more metaphoric helix, the twisted-together nucleus of references, humiliations, ambitions, smells and sources of light that form what used to be called a soul. Ours is a bookish family, but even if the referents are tire swings and swimming holes and ponds more than the first time I met Daisy Buchanan or felt sorry for Pnin, still it is that panoply of reference that shapes my thoughts and feelings. We know each other better than anyone else, and at the same time know less than many others about how the day works — have intimate knowledge of the foundations, even of what’s at the bottom of the bird cage, though we may live in complete ignorance of the patterns and rituals of the day.
