ABSTRACT
Descriptive metaphysics is interested in discovering what principles tacitly underpin people's intuitive judgments about unity. According to Gestalt psychology, then, people have built-in principles of organization that jointly compose or determine their conception of object unity. However, while the Gestalt principles do well in accounting for adult patterns of object organization, recent work in developmental psychology, especially by Elizabeth Spelke and her co-workers, raises doubts about the applicability of these principles to infants. Prescriptive metaphysics is not simply concerned with a description or reconstruction of folk ontology; rather, it seeks to provide & proper ontology; one sensitive to the findings of science and the critical reflections of philosophy. In the history of metaphysics, revisionary metaphysics has had different sources. The chapter illustrates metaphysical dialogue by reference to object unity, categorical schemes, colour, and essence. But other problems of metaphysics, such as the nature of causality, may also be open to helpful contributions from cognitive science.
