Aristotle turns to the question of how people should be educated in his ideal city. This is a matter of determining both the suitable aim of education and the proper means to achieve this end. This end, as both the Politics and the Nicomachean Ethics make clear, is a life of good quality, or happiness. To the extent of having such things as health and wealth, this happiness is partly contingent on fortune. But absolute, positive happiness (as opposed to simply the absence of unpleasantness) depends on the knowledge and purpose of the individual or city.
Aristotle argues that people can be made good through nature, reason, and habit. In his earlier discussion of nature, he concludes that the Greek combination of high spirit, skill, and intelligence is ideal. He holds off on explaining how reason and habit should be taught.
Aristotle states that in a city of equal citizens, everyone should take turns ruling and being ruled. The younger should first learn how to be ruled properly before they themselves take a hand in government.
Aristotle distinguishes within the soul a part that rules (reason) from a part that is not rational but that can be ruled by reason (feelings, passions, or qualities). Reason, the superior part, can further be divided into practical and speculative aspects. The practical aspect is important, but speculative reason is the ultimate end in itself. Military concerns, far from being a priority, should only be a security measure. A number of virtues—particularly wisdom and temperance—are necessary to make proper use of leisure time.
Aristotle returns to the question of how reason and habit should be trained, concluding that habit should be dealt with first. As babies, humans have only desires and appetites, whereas reason, the end toward which we train our habits, is a later development.
Aristotle addresses questions of marriage and childbirth that serve as preliminaries to raising a child. He believes that conception should take place in the winter and when the wind is northerly. He recommends that men marry at the age of thirty-seven and women at eighteen, that they cease reproducing about seventeen years later, and that they both keep in reasonably good physical shape without overexerting themselves. He also considers questions of inducing miscarriage or leaving babies to die of exposure in order to limit the population and recommends harsh punishment for adultery.
Aristotle further believes that newborns should be raised on milk, encouraged to move about, and inured to the cold. Up to the age of five, children should play games that involve movement, be told stories, and be protected from anything that is low and vulgar, including bad language, indecent pictures, and slaves. Up to the age of seven, children should observe the older students, and then engage in proper study from the ages of seven to twenty-one, divided into periods before and after puberty.
Aristotle's discussion of education, like the discussion of happiness, involves a distinction between means and end. One can interpret his emphasis on instilling virtues into young children as a dignified prioritization of the good man as the ultimate end. Since Aristotle so closely links individual and state, however, one can also argue that this value-obsessed education strips children of their freedom and renders them the means to the end of a good citizenry. Either way, Aristotle perceives what has become an integral component of modern psychology—that what one is exposed to at a young age makes a deep impression on one's psyche.
The close similarities that Aristotle perceives between nature and human reason and between the life of the city and the life of the individual lead him to make logical extensions of these comparisons. Since Aristotle believes that humans do everything for a reason, he believes that nature must do everything for a reason as well. This in turn suggests to him that nature has made humans rational for a reason; he thus concludes that man is essentially a rational animal and that the exercise of reason is his highest function. Likewise, since Aristotle believes that happiness and speculative reason are the highest goals of the individual, he believes that they are the highest goals of the city as well. Aristotle then applies the ruling-ruled component model of the city—in which citizens rule and slaves are ruled—to the human mind, suggesting that the rational part rules and the irrational part is ruled.
The division of rationality into practical and speculative elements gives rise to the question of each element's relative value to the city, and it is a central tension in the Politics. Aristotle has claimed that man is a political animal who gains full exercise of his reason only within the bounds of the city. This would seem to suggest that the practical reason of political activity is essential to man. Aristotle suggests, however, that both city and practical reason are only means to the ultimate end of happiness found through the practice of pure, speculative reasoning.
Aristotle's arguments rest on a series of analogies (between nature, the individual, and the state) that he never questions. In general, the modern reader tends not to ascribe to nature the same rationality he does to man. Modern theories of evolution and quantum mechanics suggest that nature is governed more by chance than by reason. Furthermore, modern thought also draws a distinction between the individual and the state that would have been alien to Aristotle. Modern political philosophy posits that the state and the individual are separate entities and poses an important question as to the extent to which the state should be allowed to impose itself on the individual. The closest Aristotle comes to recognizing a tension between individual and state is in his acknowledgement of the tension between practical and speculative reasoning.