As then our present study, unlike the other branches of philosophy, has a practical aim (for we are not investigating the nature of virtue for the sake of knowing what it is, but in order that we may become good, without which result our investigation would be of no use), we have consequently to carry our enquiry into the region of conduct, and to ask how we are to act rightly; since our actions, as we have said, determine the quality of our dispositions.2. [2]
Now the formula ‘to act in conformity with right principle’ is common ground, and may be assumed as the basis of our discussion. (We shall speak about this formula later,1 and consider both the definition of right principle and its relation to the other virtues.)