This book provides the first critical edition of John Henry Newman's classic work, A Grammar of Assent. The editor's introduction contains a synopsis of Newman's argument as well as an account of the development of his thought and a history of the composition of the final text. Ker discusses critical reaction to the Grammar and attempts to clarify and interpret Newman's thoughts in areas where his meaning has been misunderstood. A Textual Appendix lists every variant published in Newman's lifetime and the editor's Notes include detailed references to Newman's other writings. full use has been made of the manuscript drafts and all available philosophical notebooks and papers.