If you spend much time with children, you're bound to wonder how young human beings can possibly learn so much so quickly. Philosophers, going all the way back to Plato, have wondered, too, but they've never found a satisfying answer. My five-year-old grandson, Augie, has learned about plants, animals and clocks, not to mention dinosaurs and spaceships. He also can figure out what other people want and how they think and feel. He can use that knowledge to classify what he sees and hears and make new predictions. He recently proclaimed, for example, that the newly discovered species of titanosaur on display at the American Museum of Natural History in New York City is a plant eater, so that means it really isn't that scary.