Eleven-year-old children have a pretty good idea of how baseball works. Yet, as Ray Jackendoff will show, the concepts involved in baseball are remarkably complex and subtle. So the question is: What cognitive resources do children bring to the task of learning baseball, such that they manage to understand it so readily? Professor Jackendoff will examine seven aspects of the understanding of baseball, in each case looking for its place in the larger ecology of human cognition. These aspects include: cooperation and competition; rules of the game and strategies; balls, strikes, runs, and outs; taking roles (such as pitcher and umpire) within the frame of the game; the logic of groups, including teams; how humans make up new systems such as games; and why humans like games, both as players and spectators.