In this book the author indicates the part played by the scholars and physicians of Islam, especially of Persia, in the transmission of medical science through the dark ages, from the decline of the ancient to the rise of the modern learning. He also suggests to lovers of Arabic and Persian literature that they had hitherto allowed the poets and euphuists to occupy a disproportionate amount of attention to the exclusion of the scientific weltanschauung (world view) which forms the background of these lighter, through more artistic efforts.