by Elisabeth Malkin, International Herald Tribune, France - Jesús León Santos is a Mixtec Indian farmer who will soon plant corn on a small plot next to his house in time for the summer rains. He plows with oxen and harvests by hand. Under conventional economic logic, León is uncompetitive. His yields are just a small fraction of what mechanized agriculture churns out from the vast expanses of the Great Plains in the United States. But to him, that is beside the point.