People are unlikely to be naturally virtuous, so the state is responsible for establishing laws to ensure that the young are educated in the right way and that adults do not become bad. In the absence of good laws, people must take responsibility for their children and friends. Parental supervision is in many ways preferable to laws, since it allows for more particularized attention.
Neither politicians nor sophists are particularly suited to teaching politics. In order to judge how best to establish laws that will benefit citizens, we must turn to an examination of politics.
It might seem strange that we have a discussion of pleasure at the beginning of Book X, when this topic was already addressed in Book VII. There are two answers to this peculiarity. The first is that Book VII and Book X were most likely written at different times and for different purposes, and were only later interpolated into the same book. Books V, VI, and VII of the Nicomachean Ethics also feature in the Eudemian Ethics, which is Aristotle’s other, less known work on ethics. These two works were probably composed at different points in Aristotle’s career, and it is possible that the compiler of the Nicomachean Ethics took these three books from the Eudemian Ethics and inserted them into a significantly different work.
The different times of composition also explains why Aristotle’s views on pleasure differ somewhat between Books VII and X. Most notably, Aristotle implies that pleasure is supremely good in Book VII, but in Book X he is more reserved on this point, noting that certain good things, like excellent eyesight or intelligence, are not necessarily pleasant. Perhaps good eyesight and intelligence bring us pleasure from time to time, but there is nothing about seeing well that is in itself always pleasant. Though there is some debate on this topic, most scholars agree that Book X represents Aristotle’s more mature views on pleasure.
The second explanation of the disparity between Books VII and X is that they deal with different subject matter. The discussion of pleasure in Book VII follows a discussion of incontinence and is meant to illuminate what pleasure is that it should lead people to act against their better judgment. The discussion of pleasure in Book X leads to a discussion of happiness and the good life, and is meant to show in what way pleasure is connected to the good life.
Book X also gives us Aristotle’s ultimate judgment of what constitutes the good life. While the moral virtues are fine and important, rational contemplation is the highest activity. This may not be immediately evident, so we should first examine how Aristotle arrives at this conclusion and then question whether it is correct.