Abstract: According to the popular coherence theory of knowledge and justification, if a person's beliefs are coherent, they are also likely to be true. This book is the most extensive and detailed study of coherence and probability to date. The book takes the reader through much of the history of the subject, from early theorists like A. C. Ewing and C. I. Lewis to contemporary figures like Laurence BonJour and C. A. J. Coady. The arguments presented are general enough to cover coherence between any items of information, including those deriving from belief, memory, or testimony. It is argued that coherence does not play the positive role that it is generally ascribed in the process whereby beliefs are acquired. The opposite of coherence, incoherence, is nonetheless the driving force in the process whereby beliefs are retracted.

Keywords: belief, belief acquisition, coherence, incoherence, justification, knowledge, memory, probability, testimony, truth