Many actions are done by doing other things: I buy the house by writing the cheque, which I do by signing my name, which I do by writing the individual letters. The idea of a basic action is of that which I just do, but not by doing anything else. It should not be identified with making things happen further and further back in the nervous system: if a person can make a physiological event happen in the brain stem or upper body, it would be by doing such macroscopic things as clenching the fist or blinking, in a situation in which these actions have the effect on the nervous system. This is just to say that the order of explanation of events in terms of actions is not the same as the neurophysiological order of these occurrences.
Philosophy dictionary. Academic. 2011.