Nicomachean Ethics, I.2

If, then, there is some end of the things we do, which we desire for its own sake (everything else being desired for the sake of this), and if we do not choose everything for the sake of something else (for at that rate the process would go on to infinity, so that our desire would be empty and vain), clearly this must be the good and the chief good. Will not the knowledge of it, then, have a great influence on life? Shall we not, like archers who have a mark to aim at, be more likely to hit upon what is right? If so, we must try, in outline at least, to determine what it is, and of which of the sciences or capacities it is the object. It would seem to belong to the most authoritative art and that which is most truly the master art. And politics appears to be of this nature; for it is this that ordains which of the sciences should be studied in a state, and which each class of citizens should learn and up to what point they should learn them; and we see even the most highly esteemed of capacities to fall under this, e.g. strategy, economics, rhetoric; now, since politics uses the rest of the sciences, and since, again, it legislates as to what we are to do and what we are to abstain from, the end of this science must include those of the others, so that this end must be the good for man. For even if the end is the same for a single man and for a state, that of the state seems at all events something greater and more complete whether to attain or to preserve; though it is worth while to attain the end merely for one man, it is finer and more godlike to attain it for a nation or for city-states. These, then, are the ends at which our inquiry aims, since it is political science, in one sense of that term.

This section is a great example of why it's important to take the introduction slowly. There is a whole lot going on in this short piece of writing, which I have quoted in full.

Aristotle sets aside infinite regress as a possibility. This is more fully argued elsewhere, but it is of great importance -- it is indeed crucial for theology because it proves the existence of God, as Avicenna spells out in his metaphysics. Briefly, you exist obviously; where did you get existence? You got it from your parents, who already existed. Thus, we inherit existence from something that already exists. Avicenna has two arguments, which he inherited from the Greeks, about why this cannot work as an infinite regress. There has to be something that really exists to found the existence of everything else, something that exists necessarily rather than accidentally: and that, Avicenna says, is God. 

For us in this work, we aren't looking for God. We are, however, also needing to ground our desires. Maybe you desire a promotion at work; why? Perhaps because it comes with more money or greater respect, or both; why do you want those things? Perhaps because they could better allow you to attract a mate; why do you want that? Perhaps because.... if this goes on forever, Aristotle is saying, you won't ultimately really want anything at all. But you do want things. Thus, some things need to be desired for themselves. 

There's a lot more we won't get here about how we determine what those things are, and which ones are more valuable. In the Rhetoric, for example, we will learn that when incomparable things are being weighted against each other -- should I prefer this meal, or that victory at war? -- honor provides the common ground for valuation. This is an important concept to the EN (Nicomachean Ethics, for reasons pertaining to Latin, is shortened to EN) that isn't explicit in the EN. When good men sit together and talk about what is most worthy of honor, that is when they find they can in fact compare what seem to be incomparable things. Apples and oranges are comparable in terms of the price assigned to them, but all things are comparable in terms of what degree of honor they merit. The victory is obviously worth more than the meal, even if you are very hungry.

Also in this section we learn that politics is a kind of extension of ethics. This is not obvious, but it is central to Aristotle's approach. Ethics is about how to live well as a human being; politics is about how to structure a society that supports the best kind of life. The value of doing this becomes apparent as we consider the human condition. It is possible to live well in conditions of oppression or tyranny; perhaps some of the very highest things can only be achieved given the opportunity to resist tyranny. (Perhaps that is why very comfortable Americans tend to describe relatively tame matters as tyrannical: they are striving for the greatness that comes from bravely resisting tyranny.) To have a society that is structured to support the good life, though, makes everyone's life better and the best life easier to obtain for everyone. We should want that.

We still have a lot of problems, but the goal is shaping up. In ethics we are trying to shape a life that attains the best qualities that a good person ought to desire in himself or herself; and in politics, therefore, we should be aiming at a society that supports that goal for its citizens. That's what we do want, and it is what we ought to want.