In the days when Jean Piaget and Sigmund Freud dominated thinking about child development, small children were thought to be irrational, incoherent, and solipsistic in their thinking and both easily distractible and unfocused in their awareness of the world. Recent work in developmental psychology offers a sharply contrasted picture. "Children are unconsciously the most rational beings on earth," says Alison Gopnik, "brilliantly drawing accurate conclusions from data, performing complex statistical analyses, and doing clever experiments." And not only does empirical work reveal this about babies and small children, but what is thus revealed throws light on some of philosophy's more intriguing questions about knowledge, the self, other minds, and the basis of morality.

Such are the claims made by philosopher and developmental psychologist Alison Gopnik in this fascinating account of the growth of child minds. Gopnik's affectionate and sympathetic enjoyment of the way children think in their first five years is manifest throughout her book, but so too is her sensitivity to the deeper philosophical implications of what their way of thinking can teach us. The result is absorbing and educative. This is despite the fact that, at times, it seems as if developmental psychology provides arduous scientific confirmation for what parents and preschool teachers have always long known; but Gopnik is skilled at producing the rabbit of insight from an apparently old hat. And there is also much that is new and surprising in the field, all of it promising to change our understanding of mind in general.