Abstract
As I see bus no. 29 approaching, I raise my arm. The bus stops, I take a few steps and get on it. This happens because the driver, having seen my arm raised, interpreted the gesture as a conventional expression of my wish to get on the bus. If it had been bus no. 17, I would not have raised my arm because I know that that bus follows quite a different route. This is not, of course, the end of the story. I might also mention the reasons why I really wanted route 29, and so on. Fortunately, there is no need to go into the details. The important point is that in the explanation of this trivial set of actions I can quite naturally appeal to a number of mental states: perceptions, beliefs, interpretations, desires, etc. The previous story assumes, for instance, that.