In IX.9-12, Aristotle finishes off his consideration of love and friendship by wondering how many close relationships one really needs, the times in life when such relationships are most valuable, etc.
The first question is whether the person who leads a life of fulfillment (εὐδαιμονία / eudaimonia) needs any friends at all. One of the conditions for fulfillment, discussed in I.7, is that the complete good is characterized by αὐτάρκεια / autarkeia, typically rendered as "self-sufficiency" although I prefer "wholeness". Aristotle points out that it's absurd to say the fulfilled person wouldn't need close relationships, because we think such a person has all good things and loved ones are the greatest of external goods. The reason is that human beings are inherently social and we're naturally made for sharing the activities of life [συζήν / suzēn] with other people. Indeed, we can be more continuously [συνεχῶς / sunechōs] active if we are active with others; since fulfillment consists of activity [ἐνέργεια / energeia], and since activity consistent with core human capacities and directed by thriving of character is both beautifully right and enjoyable, the more active we are the more fulfilled we are. Thus the person who takes life seriously needs loved ones who are just as serious [σπουδαῖος / spoudaios].
Furthermore, because for human beings living in the most authoritative sense simply is awareness [ἄισθησις / aisthesis] and thinking [νοήσις / noēsis], sharing the activities of life consists most of all in conversing [λόγος / logos] together and thinking things through [διανοία / dianoia] together.
Yet we can't expect to build close relationships with very many people; going through life together might not be completely exclusive, but it's a rather special state of affairs. Indeed, Aristotle notes that the celebrated friendships are all pairs - say, Achilles and Patroklus in the Iliad or, to choose a slightly more modern example, Michel de Montaigne and Étienne de La Boétie as recounted in Montaigne's essay Of Friendship. We're fortunate to find even a few such friends in life, perhaps only one.
Although we say that "a friend in need is a friend indeed", Aristotle says that it's more beautifully right [καλός / kalos] to share in good fortune than in bad fortune, because as mentioned in IX.4-7 success enables us to demonstrate in "well-action" [εὐέργεται / euergetai] that we stand in a relation of "well-mindedness" [εὐνοία / eunoia] toward our friends.
Finally, Aristotle observes that whatever we think are the essential activities of life are the ones that we prefer to pursue with those who are dear to us: athletes exercise together, musicians make music together, philosophers philosophize together, etc. Moreover, these activities have a reinforcing effect: if the activities are bad then they further corrupt the people who engage in them, whereas if the activities are good then by putting the friendship into action [ἐνεργοῦντες / energountes] the friends straighten each other out [διορθοῦντες / diorthountes] and thus become better together. This ethical component is a big reason why philia was valued so highly in ancient Greece.
Thus we come to the end of Aristotle's analysis of love and friendship. We have one more book of the Nicomachean Ethics to cover in our walk with Aristotle, starting with his second discussion of pleasure and enjoyment in X.1-5.
(Cross-posted at philosopher.coach.)
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