The " Great Leaders Series" aims to meet the needs of moral and religious secondary education. Adolescence is preeminently the period of Idealism. The naive obedience to authority characteristic of childhood is to a large extent supplanted at this time by self-initiative; by self-determination in accordance with ideals adopted or framed by the individual himself. Furthermore, the ideals of this period are concrete rather than abstract. They are embodied in individual lives, and, generally, in lives of action. Hence biographies of great leaders appeal strongly to the adolescent. They furnish...