It is tempting to think that, if a person's beliefs are coherent, they are also likely to be true. Indeed, this truth-conduciveness claim is the cornerstone of the popular coherence theory of knowledge and justification. Hitherto much confusion has been caused by the inability of coherence theorists to define their central concept. Nor have they succeeded in specifying in unambiguous terms what the notion of truth-conduciveness involves. This book is the most extensive and detailed study of coherence and probable truth to date. Erik Olsson argues that the value of coherence has been generally overestimated; it is severely problematic to maintain that coherence has a role to play in the process whereby beliefs are acquired or justified. He proposes that the opposite of coherence, i.e. incoherence, can still be the driving force in the process whereby beliefs are retracted, so that the role of coherence in our enquiries is negative rather than positive. Another innovative feature of Olsson's book is its unified, interdisciplinary approach to the issues at hand. The arguments are equally valid for coherence among any items of information, regardless of their sources (beliefs, memories, testimonies, and so on). Writing in accessible, non-technical language, Olsson 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. Against Coherence will make stimulating reading for epistemologists and anyone with a serious interest in truth.

1. Introduction Part I: Does coherence imply truth? 2. Coherence, truth, and testimony 3. C. I. Lewis's radical justification of memory 4. Laurence BonJour's radical justification of belief 5. C. A. J. Coady's radical justification of natural testimony Part II: Does more coherence imply higher likelihood of truth? 6. Making the question precise 7. A negative answer Part III: Other views 8. How not to regain the truth connection: a reply to Bovens and Hartmann 9. Other coherence theories Part IV: Scepticism and incoherence 10. Pragmatism, doubt, and the role of incoherence Appendix A: Counterexample to the Doxastic Extension Principle Appendix B: Proof of the Impossibility Theorem Appendix C: Proofs of Observations

Erik J. Olsson , University of Lund, Sweden