I've been trying to learn a bit about communitarian philosophy, but I'm having a hard time wrapping my head around it. The thrust of the line of thinking seems to be that individuals are socially constituted beings and that the community should therefore be the focal unit of ethical and political action, rather than the individual (which is what is advocated by the liberal theorists communitarians criticize). That is, at least, the impression I'm getting. I may be confused, but there seems to be a problem here. Communitarians seem to want to exclude contingent "lifestyle enclaves" from their thought, defining community instead in geographical, historical and familial terms - i.e. communities we can't escape being defined into, no matter how hard we might try. But just because a person is part of a particular racial, geographical, linguistic and socioeconomic community does not mean logically imply that that community is the best place for them to flourish in the way they desire. What does communitarian thought have to say about people who don't want to participate in their communities, or who wish to live in ways that are at odds with the practices of their communities? Is the desire to flourish in ways not valued by one's community pathological in communitarian thought, even if the way a person may want to live is not harmful?

Excellent set of concerns! The history of communitarianism is a bit complex; the term was first introduced by a German sociologist F. Tonnies (d1936), but the term did not really get a lot of philosophical attention until we get the mature work of Alasdair MacIntyre and Charles Taylor. I suspect that the form of communitarianism is a very radical one that rules out appeal to concepts of human flourishing that may be used to critique or evaluate communities. Both MacIntyre and Taylor stress the vital importance of communities as philosophically significant contexts for moral, religious, and political reflection but both embrace moral theories that go beyond what a community happens to value. Although I am not positive, MacIntyre seems closest to an Aristotelian perspective in his latest work. Taylor may lean a little more toward the Platonic tradition, but for both of these figures who have promoted communitarianism, religious values (both philosophers are Roman Catholic) are viewed as having a great importance that is missing in secular communities.

Back to your original worry: I share it. More radical forms of communitarianism could well overwhelm and threaten an individual's bona fide flourishing, and that is indeed a problem.

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