This paper advances a unified theory of skillful and intentional action. According to our theory, the distinguishing feature of both skillful and intentional actions is that they are guided by the agent’s knowledge of the means of performing the task at hand. This theory leads naturally to an intellectualist view of skills, according to which skills are propositional knowledge states. We show that this view enjoys a number of explanatory advantages over more familiar dispositional accounts of skills.

What is it to believe something might be the case? We develop a puzzle that creates difficulties for standard answers to this question. We go on to propose our own solution, which integrates a Bayesian approach to belief with a dynamic semantics for epistemic modals. After showing how our account solves the puzzle, we explore a surprising consequence: virtually all of our beliefs about what might be the case provide counterexamples to the view that rational belief is closed under logical (...) implication. (shrink)