I first provide an analysis of Joel Feinberg’s anti-paternalism in terms of invalidation of reasons. Invalidation is the blocking of reasons from influencing the moral status of actions, in this case the blocking of personal good reasons from supporting liberty-limiting actions. Invalidation is shown to be distinct from moral side constraints and lexical ordering of values and reasons. I then go on to argue that anti-paternalism as invalidation is morally unreasonable on at least four grounds, none of which presuppose that (...) people can be mistaken about their own good: First, the doctrine entails that we should sometimes allow people to unintentionally severely harm or kill themselves though we could easily stop them. Second, it entails that we should sometimes allow perfectly informed and rational people to risk the lives of themselves and others, though they are in perfect agreement with us on what reasons we have to stop them for their own good. Third, the doctrine leaves unexplained why we may benevolently coerce less competent but substantially autonomous people, such as young teens, but not adults. Last, it entails that there are peculiar jumps in justifiability between very similar actions. I conclude that as liberals we should reject anti-paternalism and focus our efforts on explicating important liberal values, thereby showing why liberty reasons sometimes override strong personal good reasons, though never by making them invalid. (shrink)