I wish to express my sincere thanks to Dean Andrew F. West of thegprinceton Graduate School for his unfailing interest in my work. It was in one of his graduate courses that the translation was begun, three years ago, and at his suggestion that I undertook the composition of the thesis in its present form. He has read the entire treatise in the manuscript, and has been my constant adviser and critic. Thanks are also due to Dr. Charles G. Osgood of the English Department of Princeton University for reading the translation.