An action is an event that an agent performs for a purpose, that is guided by the person's intention. The first question in the philosophy of action is to determine how actions differ from other forms of behavior, like involuntary reflexes. According to Ludwig Wittgenstein, it involves discovering "[w]hat is left over if I subtract the fact that my arm goes up from the fact that I raise my arm". There is broad agreement that the answer to this question has to do with the agent's intentions. So driving a car is an action since the agent intends to do so, but sneezing is a mere behavior since it happens independent of the agent's intention. The dominant theory of the relation between the intention and the behavior is causalism: driving the car is an action because it is caused by the agent's