We hope this book will demonstrate that scientists and children belong together in still other ways. Parents are deeply, even passionately interested in children, or at least in their children. But parents find that their interest in children is treated differently from their interest in science. Books about science assume that their readers are serious, knowledgeable, intelligent, sophisticated adults who simply want to know about the things they care about. But books about babies and children are almost all books of advice—how-to books. It's as if the only place you could read about evolution was in dog-breeding manuals, not in Stephen Jay Gould; as if, lacking Stephen Hawking’s insights, the layman's knowledge of the cosmos was reduced to “How to find the constellations.”