In Semantic and Conceptual Development, Frank Keil presents the firstpsychological investigation of thedeveloping child's ontological knowledge. Building on previous philosophical work, Keil shows that ontologicalcategories develop in a highly predictable progression. Moreover, Keil demonstrates that ontological development obeys a strong formal constrainton the relations among categories.Although there are many possibleontological systems, children appearto be inherently targeted to consider asystem of only one sort.

Keil's results represent exactly the sortof interdisciplinary study of thehuman mind which is graduallyemerging as the new field of cognitivescience. We are proud to publish hiswork as the first book in the CognitiveScience Series, which is designed tofoster major empirical and theoreticalcontributions to this new field.