“It is not always American writing that most deeply impresses Americans. So I do not apologize for the curious book in which I have taken most pleasure during the last decade — Ronald Knox’s sole masterpiece, Enthusiasm. Supposedly it is a history of Christian heresies and on that basis it is superb. But I find it something more important. It is also a history of recurrent patterns of the human mind, as applicable to literature, politics and government as to religion. Montanism and Donatism, Albigensianism and Jansenism — puritanism, evangelism, rationalism and superrationalism, quietism, relaxation — they are all constantly erupting phenomena of man’s temperament. To be acquainted with this scholarly, brilliantly witty, crotchety book is to be better acquainted with the planet and its odd occupants.” Phyllis McGinley, Outstanding Books, 1931–1961