Preface; List of contributors; 1. Introduction: the ecological and intellectual bases of categorisation Ulric Neisser; 2. From direct perception to conceptual structure Ulric Neisser; 3. Category cohesiveness, theories and cognitive archaeology Douglas L. Medin and William D. Wattenmaker; 4. Cognitive models and prototype theory George Lakoff; 5. The instability of graded structure: implications for the nature of concepts Lawrence W. Barsalou; 6. Decentralised control of categorisation: the role of prior processing episodes Lee R. Brooks; 7. Conceptual development and category structure Frank C. Keil; 8. Child-basic object categories and early lexical development Carolyn B. Mervis; 9. Scripts and categories: interrelationships in development Robyn Fivush; 10. How children constrain the possible meanings of words Ellen M. Markman; 11. The role of theories in a theory of concepts Robert N. McCauley; Indexes.