The reputation of Jean Piaget (1896-1980) is primarily based on his contributions to the developmental psychology of children's thinking. Less known is that his interests ranged from biological questions to psychology, mathematics, and logic, and that these individual sciences were significant to him mainly from the perspective of a theory of knowledge. His program of "genetic epistemology" seeks to answer traditional epistemological questions not philosophically, but empirically-analytically. Ingrid Scharlau demonstrates that Piaget's work poses a current challenge for philosophy and the sciences due to this claim.