A religious enthusiast verging on zealotry, Johann Kaspar Lavater lived the life of a pastor in Zurich--counseling prisoners on death row, working in an orphanage, and preaching Sunday sermons. At the same time, he engaged leading intellectuals of his day in debate: he exchanged letters, visits, and ideas first with the new generation of Sturm-und-Drang writers, including Johann Wolfgang Goethe and Johann Gottfried Herder, with whom he shared a passion for life and letters; and later with those of a more rationalistic persuasion, such as Gotthold Ephraim Lessing and Georg Christoph Lichtenberg, who constantly challenged his positions. From the blend of his stable personal and professional life with his controversial intellectual activities came a broad range of writings, from tender expressions of care for children, reasoned advice for adolescents, consoling words for social outcasts, and intuitive statements on character interpretation through the study of facial features, to patriotic...