  Judgement internalism is a plausible view, and, if it is true, that spells trouble for moral naturalists. Plausibly, if a moral judgement is just a belief to the effect that some natural fact obtains, I might at least conceivably hold that belief and simply not give a damn. In which case, if naturalism is true, internalism must be false. But many philosophers—particularly expressivists—hold that judgement internalism is true. So much the worse for naturalists.