In Nicomachean Ethics and Politics, Aristotle explores the disciplines of ethics and political science. As ethics deals with the individual person, political science deals with the political community. On a basic level, Aristotle binds political science to ethics by taking the fundamental stance that both aim towards some end. His first sentence in Nicomachean Ethics argues that “every action and decision” appears to “aim at some good”. The first sentence in Politics is strikingly similar, stating that “every community is constituted for the sake of some good”.
The type of analysis we see employed in Nicomachean Ethics and Politics - coming to know a subject by understanding its purpose - is central to Aristotelian thinking. Aristotle makes widespread use of teleology in his arguments elsewhere, appealing to it even to account for motion and change. Thus, we should not be particularly surprised by Aristotle's end-oriented analysis of both political science and ethics. Indeed, we might further argue that there may be limited value in pointing out this parallel; since teleology is such a basic tenet in Aristotle's thinking, we gain little insight by simply recognizing its use in both Politics and Nicomachean Ethics.
However, there is something more than a mere methodological parallel present in Aristotle's treatment of ethics and political science. Not only are the two sciences comparable due to the fact that they aim at some end, but - crucially - in both cases this end is the same. To Aristotle, this common end is happiness. Applied to ethics, this is relatively straightforward. After considering many possible alternative ends, Aristotle argues that the end of human aims is the activity of happiness, since it is something we desire purely for itself and not for some other end. It is important to note that Aristotle views happiness as an activity, rather than as an emotion or a temporary state of mind. This makes it feasible for happiness to be the type of thing towards which a political community might also aim: we can comprehend a political community undertaking an activity, or making an activity possible, or aiming “at fine actions”, but it is not so easy to see how it might aim towards an emotion.
Indeed, to Aristotle, happiness is as much the goal of the political community as it is the goal of the individual: he argues that we should “take happiness to be the same for an individual human being and for a city.” However, Aristotle's reasoning with respect to how the political community aims towards happiness is not as direct as his argument about ethics. In Nicomachean Ethics, he establishes that happiness is the activity of study, as opposed to the activity of virtues concerned with action, such as those exemplified by a soldier or a politician. These virtues concerned with action are “choiceworthy for some end other than themselves”, and thus are not concerned directly with happiness as an end in itself. Study, or understanding, aims at “no end beyond itself”, and thus the studious life is the happy one.
Having established that the happy individual will be the one who pursues learning, Aristotle stipulates that at least two things are required for this to be made possible. First, the happy individual must have the proper character, formed through habituation, to engage in and benefit from study. Second, time for leisure is crucial for the learned individual, since this is when learning of the type in which Aristotle is interested can occur. To Aristotle, the political community in its best variety aims toward ensuring these preconditions for ethics are met. In this way, the political community aims towards the activity of happiness just as surely as does the individual, albeit not as directly.
Aristotle deals explicitly with how the political community must meet these criteria. Indeed, the very purpose of political science is to provide an outline for how this is to be done. However, Aristotle does not make specific prescriptions with respect to what the political community must do. Just as in Nicomachean Ethics he does not direct the individual to become anything in specific - a painter, an architect, a soldier - in order to live a happy life, in Politics he does not favour particular laws or particular politicians in order to achieve the correct end. Instead, he directs his investigation towards the types of political communities that might be realized, and comments on whether each will fulfil the proper goal.
It is obvious to Aristotle that, whatever type of political system may emerge as suitable, the community it governs will be a city. Indeed, Aristotle's first argument in Politics holds that the city is the community that most of all aims at “the good that most of all controls all the other goods”, which he later shows to be happiness. Aristotle proceeds to investigate the types of system that may govern the city, ordering them into a hierarchy according to how successfully they fulfill the correct aim of a political community: some are “prior”, and others “posterior”. Aristotle uses two criteria to determine which is the most prior: rule must be according to the common advantage, and all citizens must share in rule.
