Sowell concludes that all cultures are not "equal . Some are "better " than others . And the entire culture does not have to be rated as a unit . Geographical factor also creates profound differences among peoples . It is not simply that such natural wealth as oil and gold are very unequally distributed around the world . More fundamentally , people themselves are different because of different levels of access to other peoples and cultures . Isolated peoples have always lagged behind those with greater access...