Beginning with primitive society, the author goes through world history, summarizing the philosophy and statements of leaders of thought in the ancient world, Middle Ages, and modern times. As a Catholic, he sees a steady loss in morality from the Middle Ages to the present. In the 11th to 13th centuries he traces a general acceptance of divine law, Known by season and revelation and providing a norm of morality for individuals and peoples. For the next 5 centuries he sees a weakening of the supernatural world view, due to the rise of bourgeolsle capitalism and its emphasis on material things. The internationalism of the Holy See lot ground, as nationalism and secular faith began to rise. Solenos began to intoxicate the mind of man, so that he vainly tried to find in it a complete philosophy of life. The author says that the Catholic viewpoint does not hold with laissez-faire capitalism, with imperialistic nationalism, with the rugged individualism of U. S., nor with totalitarian philosophies rampant today. For guidance in thinking through our modern problems he refers all Catholics to the social encyclicals of Pope Pius XI and XII. A book for earnest readers and students.