Preface For some nineteen hundred years the Church established by Christ when He said, "Go teach all nations," has stood for all that is best in human life. The very fact that it has endured the cataclysmic changes from Roman Empire through Middle Ages and Renaissance down to modern times singles it out as a unique institution in the history of humanity. During all these profoundly trying vicissitudes of the race the Church has fostered the sense of beauty and the sense of duty. These are the sources of happiness for mankind more than any other factors. Architecture, painting, sculpture,...