In his Nicomachean Ethics, Aristotle describes the happy life intended for man by nature as one lived in accordance with virtue, while in the Politics he describes the role that politics and the political community must play in bringing about the virtuous life in the citizenry. The Politics also provides analysis of the kinds of political community that existed in his time and shows where and how these cities fall short of the ideal community of virtuous citizens. Although in some ways we have clearly moved beyond his thought (for example, his belief in the inferiority of women and his approval of slavery in at least some circumstances), there remains much in Aristotle�s philosophy that is valuable today. In particular, his views on the connection between the well-being of the political community and that of the citizens who make it up, his belief that citizens must actively participate in politics if they are to be happy and virtuous, and his analysis of what causes and prevents revolution within political communities have been a source of inspiration for many contemporary theorists, especially those unhappy with the liberal political philosophy promoted by thinkers such as John Locke and John Stuart Mill.
Biography and history
Aristotle's life was primarily that of a scholar. However, like the other ancient philosophers, it was not the stereotypical ivory tower existence. His father was court physician to Amyntas III of Macedon, so Aristotle grew up in a royal household. Aristotle also knew Philip of Macedon (son of Amyntas III) and there is a tradition that says Aristotle tutored Philip�s son Alexander, who would later be called "the Great" after expanding the Macedonian Empire all the way to what is now India. Clearly, Aristotle had significant firsthand experience with politics, though scholars disagree about how much influence, if any, this experience had on Aristotle's thought. There is certainly no evidence that Alexander's subsequent career was much influenced by Aristotle's teaching, which is uniformly critical of war and conquest as goals for human beings and which praises the intellectual, contemplative lifestyle. It is noteworthy that although Aristotle praises the politically active life, he spent most of his own life in Athens, where he was not a citizen and would not have been allowed to participate directly in politics (although of course anyone who wrote as extensively and well about politics as Aristotle did was likely to be politically influential).
Aristotle studied under Plato at Plato's Academy in Athens, and eventually opened a school of his own (the Lyceum) there. As a scholar, Aristotle had a wide range of interests. He wrote about meteorology, biology, physics, poetry, logic, rhetoric, and politics and ethics, among other subjects. His writings on many of these interests remained definitive for almost two millennia. They remained, and remain, so valuable in part because of the comprehensiveness of his efforts. For example, in order to understand political phenomena, he had his students collect information on the political organization and history of 158 different cities. The Politics makes frequent reference to political events and institutions from many of these cities, drawing on his students' research. Aristotle�s theories about the best ethical and political life are drawn from substantial amounts of empirical research. These studies, and in particular the Constitution of Athens, will be discussed in more detail below (Who Should Rule?). The question of how these writings should be unified into a consistent whole (if that is even possible) is an open one and beyond the scope of this article. This article will not attempt to organize all of Aristotle's work into a coherent whole, but will draw on different texts as they are necessary to complete one version of Aristotle's view of politics.
Politics and ethics
In Book Six of the Ethics Aristotle says that all knowledge can be classified into three categories: theoretical knowledge, practical knowledge, and productive knowledge. Put simply, these kinds of knowledge are distinguished by their aims: theoretical knowledge aims at contemplation, productive knowledge aims at creation, and practical knowledge aims at action. Theoretical knowledge involves the study of truth for its own sake; it is knowledge about things that are unchanging and eternal, and includes things like the principles of logic, physics, and mathematics (at the end of the Ethics Aristotle says that the most excellent human life is one lived in pursuit of this type of knowledge, because this knowledge brings us closest to the divine). The productive and practical sciences, in contrast, address our daily needs as human beings, and have to do with things that can and do change. Productive knowledge means, roughly, know-how; the knowledge of how to make a table or a house or a pair of shoes or how to write a tragedy would be examples of this kind of knowledge. This entry is concerned with practical knowledge, which is the knowledge of how to live and act. According to Aristotle, it is the possession and use of practical knowledge that makes it possible to live a good life. Ethics and politics, which are the practical sciences, deal with human beings as moral agents. Ethics is primarily about the actions of human beings as individuals, and politics is about the actions of human beings in communities, although it is important to remember that for Aristotle the two are closely linked and each influences the other.
The fact that ethics and politics are kinds of practical knowledge has several important consequences. First, it means that Aristotle believes that mere abstract knowledge of ethics and politics is worthless. Practical knowledge is only useful if we act on it; we must act appropriately if we are to be moral. He says at Ethics 1103b25: "The purpose of the present study [of morality] is not, as it is in other inquiries, the attainment of theoretical knowledge: we are not conducting this inquiry in order to know what virtue is, but in order to become good, else there would be no advantage in studying it."
Second, according to Aristotle, only some people can beneficially study politics. Aristotle believes that women and slaves (or at least those who are slaves by nature) can never benefit from the study of politics, and also should not be allowed to participate in politics, about which more will be said later. But there is also a limitation on political study based on age, as a result of the connection between politics and experience: "A young man is not equipped to be a student of politics; for he has no experience in the actions which life demands of him, and these actions form the basis and subject matter of the discussion" (Ethics 1095a2). Aristotle adds that young men will usually act on the basis of their emotions, rather than according to reason, and since acting on practical knowledge requires the use of reason, young men are unequipped to study politics for this reason too. So the study of politics will only be useful to those who have the experience and the mental discipline to benefit from it, and for Aristotle this would have been a relatively small percentage of the population of a city. Even in Athens, the most democratic city in Greece, no more than 15 percent of the population was ever allowed the benefits of citizenship, including political participation. Athenian citizenship was limited to adult males who were not slaves and who had one parent who was an Athenian citizen (sometimes citizenship was further restricted to require both parents to be Athenian citizens). Aristotle does not think this percentage should be increased - if anything, it should be decreased.
Third, Aristotle distinguishes between practical and theoretical knowledge in terms of the level of precision that can be attained when studying them. Political and moral knowledge does not have the same degree of precision or certainty as mathematics. Aristotle says at Ethics 1094b14: "Problems of what is noble and just, which politics examines, present so much variety and irregularity that some people believe that they exist only by convention and not by nature�.Therefore, in a discussion of such subjects, which has to start with a basis of this kind, we must be satisfied to indicate the truth with a rough and general sketch: when the subject and the basis of a discussion consist of matters that hold good only as a general rule, but not always, the conclusions reached must be of the same order." Aristotle does not believe that the noble and the just exist only by convention, any more than, say, the principles of geometry do. However, the principles of geometry are fixed and unchanging. The definition of a point, or a line, or a plane, can be given precisely, and once this definition is known, it is fixed and unchanging for everyone. However, the definition of something like justice can only be known generally; there is no fixed and unchanging definition that will always be correct. This means that unlike philosophers such as Hobbes and Kant, Aristotle does not and in fact cannot give us a fixed set of rules to be followed when ethical and political decisions must be made. Instead he tries to make his students the kind of men who, when confronted with any particular ethical or political decision, will know the correct thing to do, will understand why it is the correct choice, and will choose to do it for that reason. Such a man will know the general rules to be followed, but will also know when and why to deviate from those rules. (I will use "man" and "men" when referring to citizens so that the reader keeps in mind that Aristotle, and the Greeks generally, excluded women from political part icipation. In fact it is not until the mid-19th century that organized attempts to gain the right to vote for women really get underway, and even today in the 21st century there are still many countries which deny women the right to vote or participate in political life).