In this work, Piaget's theory of the development and nature of knowledge is discussed in the context of 20th-century European thought, and his views are compared with those of Freud, Lacan, Heidegger, Foucault, and writers of the Frankfurt school. The text surveys Piaget's work from a number of angles, and general discussions of the main conceptual oppositions of his theory are balanced with more specific debates. Links between Piagetian and Freudian theory are explored, as are the links between Piaget's theory of self-knowedge, Foucault's account of discursive knowledge practices, and Lacan's views on the symbolic power of language. Contributors include Susan Buck-Morss, Edward S. Casey, Hans G. Furth, William J. Richardson, Charles E. Scott, and Hugh J. Silverman.