... of which man is master. Now man is master of his actions through his reason and will; whence, too, the free-will is defined as "the faculty and will of reason." Therefore those actions are properly called human which proceed from a deliberate will. And if any other actions are found in man, they can be called actions "of a man," but not properly "human" actions, since they are not proper to man as man. Now it is clear that whatever actions proceed from a power, are caused by that power in accordance with the nature of its object. But the object of the will is the end and the good. Therefore all human actions must be for an end.