On the basis of stenographic reports, without material change, I have prepared the contents of these lectures for press; so that, as far as possible, the spirit of the spoken word would be caught by the reader. The limited period set for each lecture required a curtailment of the quotations, but in most cases, they have been inserted in this volume at proper length. The close of the semester prevented he actual delivery of the concluding lecture on Islam; completeness, however, made such an omis sion here impossible.