Moore's proof, liberals and conservatives. Is there a (Wittgensteinian) third way?

It is argued that a third position, called 'moderatism', alternative to both liberalism and conservativism about the structure of empirical justification, should be countenanced. It is then shown how moderatism could be of help to shed light on the phenomenon of transmission failure, its relationship with the principle of Closure and to provide a novel diagnosis of the failure of Moore's proof. Its relationships with Wittgenstein's *On Certainty* are also explored.