A leading German metaphysician of the 19th century, Arthur Schopenhauer (1788-1860) exerted an influence far beyond the hermetic world of philosophy, with adherents ranging from Richard Wagner and Friedrich Nietzsche to Leo Tolstoy and Thomas Mann. Among Schopenhauer's chief contributions to the field of philosophy are his rejection of the idealism of his contemporaries and his embrace of a practical variety of materialism. He jettisons the traditional...