Moving on from his discussions of ideal relationships and then unequal relationships, Aristotle first takes a detour into different forms of political community (monarchy, aristocracy, democracy, etc.). This likely strikes us as strange, until Aristotle explains that philia holds societies together even more than justice does; in this context, I would translate the term as brotherhood (a somewhat attenuated kind of loving in especially short supply these days, it seems!). The idea is that philia exists to the extent that two or more people share common goals and activities, such as workmates (Aristotle's example is actually shipmates on a commercial venture), fellow soldiers, neighbors, participants in a religious order, or members of a social club. And all of these specific varieties of association exist under the broad framework of the overall society in which you live.
Aristotle observes that it is in relationships based on personal gain and usefulness that complaints and reproaches are most likely to arise. Consider life in a modern organization, where you might help a colleague with a project of theirs but not receive the same level of assistance with a project of your own; this kind of disparity, compounded over time, can cause you to rethink the entire relationship. By contrast, Aristotle says there are no complaints in stable relationships based on good character, mutual caring, and the pursuit of what's beautifully right as opposed to what's personally advantageous. A further cause of disagreement can occur when one person thinks the relationship is based on character but the other thinks it is based on usefulness or pleasure.
Yet Aristotle emphasizes that these matters can be extremely subtle: it can be difficult to figure out where you really stand, whether another person truly shares your values, when it makes sense to break off a relationship, etc. This is why we can't formulate hard-and-fast rules and instead need to develop a certain kind of wisdom [phronēsis] about human relationships.
(Cross-posted at philosopher.coach.)
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