During my recent trip to Berkeley, I was asked to give a discussion starter about Mercier and Sperber’s recent Behavioral and Brain Sciences article on the function reasoning has been given by evolution. They broadly argue that reasoning is not an internal process and evolved with its “main function” as convincing others of what we already believe. As this was a discussion starter (and the discussion went on for some time), it was not intended to be a full critique. Here are the slides:
A term like “main function” is a red rag to a philosopher. However, let me also say that I think it very likely there is no clear distinction between intuitive reasoning and public reasoning to be had – they shade into each other. Our preconscious reasoning skills are probably mutually influenced by our public expressions of it. As E. M. Forster said once, how do I know what I think until I see what I say?