Hi, I've been thinking the comments on this over and it seems to me that for one thing commercial may not be exactly the same as economic. At base level, I blelieve all biological activitiy is economic because without constant nourishment the organism dies. Economics is thus a psychological constant, and even altruism reduces to a subject's own needs. But I think it's basically the economics feeding (nourishment) system that goes back to before birth. No mother, no life, in a sense. And once born, getting fed is largely a question of advertising. A few hasty humble stabs at the question............ Best regards, Will William Bain PhD Student Comparative Literature Department of Spanish Philology Universitat Autonoma de Barcelona --------------------------------- Boardwalk for $500? In 2007? Ha! Play Monopoly Here and Now (it's updated for today's economy) at Yahoo! Games.