Reasons, justification, and defeat

Traditionally, the notion of defeat has been central to epistemology, practical reasoning, and ethics. Within epistemology, it is standardly assumed that a subject who knows that p, or justifiably believes that p, can lose this knowledge or justified belief by acquiring a so-called ‘defeater’, whether evidence that not-p, evidence that the process which produced her belief is unreliable, or evidence that she has likely misevaluated her evidence. Within ethics and practical reasoning, it is widely accepted that a subject may initially have a reason to do something although this reason is later defeated by her acquisition of further information. However, the traditional conception of defeat has recently come under attack. Some have argued that the notion of defeat is problematically motivated; others that defeat is hard to accommodate within externalist or naturalistic accounts of knowledge or justification; others that the intuitions which support defeat can be explained in other ways. This volume brings together recent work to re-examine the very notion of defeat, and its place in epistemology, and in normativity theory at large.