ABSTRACT
As civilization developed from hunting, to agriculture, to specialization and trade, there also developed the artisan or tradesman whose skill and tool-making or weaving, for example, caused him to devote more time to his trade than to the hunting or growing of food. He would obtain food in barter but at the same time he did not find it advantageous to teach his trade to all comers. He would perhaps pass it on to his son or other members of his family.
