The good for humans is proper functioning or complete life in accordance with reason and virtue, where virtue is simply proper functioning or excellence (arete) in actualizing one's distinctively human potential.

Virtue has to do with the whole life including both outward behavior and inner disposition, motivation, intention, and attitude; a virtuous person has inner direction rather than simply responding to external stimuli, and this inner functioning disposes one to proper external functioning.

Proper functioning and virtue are acquired through habit formation, specifically through repeated deliberation and choice: one must repeatedly decide and choose based on reasoned deliberation about ends and means until it becomes a settled mental habit, because one instance of virtuous action does not make one virtuous any more than one day makes a summer.

Deliberation seeks the mean (the golden mean) between extremes: a virtue represents the proper functioning of some aspect of the human soul, and proper functioning occurs neither in excess nor in deficiency but in balance—hitting the rational mean that properly orders the emotional life.

The vegetative soul's proper functioning has physical health as its end; the animal soul's sensory and emotional functions achieve proper functioning (moral virtues) when appetites, desires, and emotions are in balance; the rational soul achieves proper functioning through intellectual virtues, which include practical wisdom and contemplative wisdom.

Proper emotional functioning requires feeling emotions at the right times, with reference to the right objects, towards the right people, with the right motive, and in the right way—for example, anger should be felt appropriately, hunger should arise at appropriate times with proper direction, illustrating how the mean applies to the emotional life.

The concept of balance and proportion as the rational and just—the proper order of things—extends back to Presocratic philosophy, showing that Aristotle's doctrine of the mean is not novel but rather a classical return to a fundamental insight.

Pleasure is not an end to be pursued but a byproduct or side effect of actualizing other ends; one may be so preoccupied with evaluating a meal's worth that one fails to enjoy it, whereas pleasure is found in the fulfilling activity itself, not as a primary end in itself.

A just society is one that is rationally ordered for the common good; the good of the individual is properly ordered toward the common good, just as a virtuous individual's emotions are properly ordered; the state writ large is analogous to the human being in miniature.

Aristotle's approach to political theory differs from Plato's: Plato, seeking a transcendent ideal that exists only in the heaven of the forms, found all existing political forms unsuitable and proposed a single ideal form (philosopher kings); Aristotle, holding that forms exist only in particulars and can be imperfectly actualized in various ways, is open to alternative political constitutions.

Students often wrongly conclude Aristotle is a relativist because he talks of finding the golden mean rather than pinpointing exactly what one ought to do; but 'find the golden mean' is precisely pinpointing what one ought to do—use the gifts God has given you and make up your own mind in light of all the input you have.

Much contemporary political thinking in the United States is more Platonic than Aristotelian: it tends to assume there is only one possible form of just society (the American form) rather than recognizing there might be a variety of viable alternatives.

Poetry is more scientific than history: history merely narrates particulars and chronicles events, while poetry captures something universal and is therefore closer to science (theoretical thinking about universal principles).

Aristotle's entire political theory, aesthetics, ethics, and educational theory tend to follow from his underlying metaphysics; understanding how he gets straight the metaphysics explains how his epistemology follows and then how political thought, aesthetics, ethics, and educational theory flow from these foundations.

Plato is not talking about detached, value-free knowledge when he says knowing the good enables doing it; rather, he means a knowledge that involves loving the truth, and if one really loves the truth, one will do what it requires—but not in the sense of detached objective impersonal awareness.

Aristotle maintains ethical absolutism without transcendent Platonic forms: the good (living a complete life in accordance with reason and virtue, pursuing the virtues) is absolutely what one ought to do because even though forms are within particulars rather than transcendent, forms are still universal principles, and universals (not transcendence) are what ground ethical absolutism.

Aristotle has a transcendent being (God) and ties the good to the ordered unity which God's very being maintains and upholds; the highest contemplation is contemplation of the one who unceasingly contemplates his own contemplating (God), though Aristotle pursues this without going to the otherworldly direction that later mysticism does.

Aristotle's philosophy in every area is theological—there are certain natural ends which represent the proper functioning of things, and developing an ethic requires understanding the human soul and its proper functions: the nutritive function of the vegetative soul, the sensory and conscious functions of the animal soul, and the rational function of the rational soul which distinguishes humans.

Some people suffer from akrasia (weakness of will)—they lack the self-discipline or temperance needed to make deliberate choices and stick by them, and therefore cannot develop virtuous habits through the normal deliberative process; such people, like young children, must be ruled by other people's reason until they develop sufficient self-control.

Humans are by nature social or societal beings (in Greek, 'phusai')—this is not a random fact but follows from their essential nature and telos; humans do not function properly in isolation and are only fully human within society, so a solitary individual would be not fully human.