Some philosophers hold that it would be impossible for us to do something actively if the physical world were causally closed, i.e., if in the physical world all events were caused by other physical events if they are caused at all. The reason for this view is that these philosophers adhere to what I call the traditional picture of action. Recently, Martine Nida-Rümelin tried to defend this picture by phenomenological considerations. According to the traditional picture a behavior can only count as something an agent does actively if it is ultimately caused by the agent in an agent-causal way. In this paper I adduce three arguments against agent causation: (1) We do not really understand what agent causation is. (2) If agent causation were ...