Erich Frank studied philology and classics at the universities of Vienna, Freiburg, and Berlin. In 1907 he turned to philosophy, which he studied in Heidelberg under Heinrich Rickert and Wilhelm Windelband. His philosophical career in Germany was brief but distinguished. In 1923 he became professor at Heidelberg, and five years later he was appointed Martin Heidegger's successor in Marburg. Three years after his dismissal from Marburg in 1936, he came to Harvard on a research fellowship and made America his second home. Almost all of Frank's works reflect his double interest in philosophy and history and his efforts to combine historical knowledge and philosophical thought: Plato und die sogennanten Pythagoreer (Halle, 1923); Wissen, Wollen, Glauben (Knowledge, will, belief), a collection of English and German historical and speculative essays, edited with an appreciation by Ludwig Edelstein (Zürich, 1955), of which the title essay represents Frank's most original contribution to...