ABSTRACT
Hume once complained about the careless procedure of philosophers who all too frequently, as he put it, began their discourses on morals with the familiar copulation 'is' and then without explanation or justification employed the quite different locution 'ought'. This chapter focuses attention upon the question whether or not matters of physiological happenings can also be described legitimately as matters of action, things done by the agent. The course of western philosophy is littered with the relics of philosophic doctrines that have attempted to legislate what science can or cannot do. The physiologist who envisages the possibility of a complete physiological explanation of bodily happenings surely has history on his side. It should be clear that not every physiological happening in the chain of causes that issue in the motion of one's arm is a case of something done. For only in very special circumstances can such a happening be described as an action.
