Unbelievable Errors

Abstract

This book defends an error theory about all normative judgements: not just moral judgements, but also judgements about reasons for action, judgements about reasons for belief, and instrumental normative judgements. This theory says that normative judgements are beliefs that ascribe normative properties, but that normative properties do not exist. It therefore entails that all normative judgements are false. The book also argues, however, that we cannot believe this error theory. Instead of being a problem for the theory, the book argues, our inability to believe this error theory makes the theory more likely to be true, since it undermines objections to the theory, it makes it harder to reject the arguments for the theory, and it undermines revisionary alternatives to the theory. The book then sketches how certain other philosophical theories can be defended in a similar way, and how philosophers should modify their methodology if there can be true philosophical theories that we cannot believe. It concludes that to make philosophical progress, we should make a sharp distinction between a theory’s truth and our ability to believe it.