Philosophical accounts of childhood have tended to derive from Plato and Aristotle, who portrayed children as unreasonable and incomplete in terms of lacking formal and final causes and ends. Despite much rhetoric concerning either the sinfulness or purity of children, the assumption that children are marginal has endured and modern theories have re-enforced this sense of incompleteness. This book seeks to overturn this philosophical tradition. It develops instead a fully semiotic perspective, arguing that in so far as children are no more or less interpreters of the world than adults, they are no more or less reasoning agents. This, the book shows, has radical implications, particularly for the question of how we seek to educate children.