Joel Hagstrom- Kendall Walton and Make Believe

Kendall Walton is an analytic philosopher whose theory on art views it as a complex game of "make believe."  His theory says that "some of the basic cognitive processes are involved both in simple children's games and in complex works of art." (The Nature of Art)  Walton says that we convince ourselves that the individual specks of paint on the campus are joined together to give us one unified image, ie. a personal portrait or landscape.  By pretending that all of these components, when put together show us a unified image, Walton says that this is a form of "make believe."  This makes me wonder if all of the playful games we all participated in when we were growing up were just conditioning so that we would interpret the world in a way that everyone else does.  If we wouldn't have experienced the "basic" components of childhood how different would our perceptions be of art and the world, today?