The presence of the past is of prime importance in today's Mexican society. According to José Fuentes Mares, among the “peoples of the world the Mexican is the one who lives history the most”. With regard to the unsatisfactory relations between Mexico and North America, the journalist Alan Riding asks himself: “How can a people who relish the past to the point of intoxication understand another that looks constantly to the future?” In the Republic of Mexico, according to him, “the entire past of the country throws a dense shadow over the present”. Conforming to a universal custom, every country divides its present past into four groups (survival, residues, memories and history), but in few nations are the four groups as copious as in this one. Although Mexico is rapidly shedding many old customs and is selling residual objects to foreign collectors on the sly, its historical treasure is still enormous, perhaps the largest in the world.