The theme of tonight's meetup is the difficulty of specifying which commitments we should endorse if the world in which we act is really, robustly plural. A plural world is a world consisting of many things, of multiplicity; our engaging with each other seems to presuppose such a field of engagement, instead of either a (solipsistic) world without plurality or (the casual relativist's) disconnected worlds in the plural.
Accepting both the sharedness and the diversity of the space in which we act can point us toward strange and unsettling implications for who we are and what we ought to think. We normally take it that things are a certain way - itself already a denial of plurality, a kind of monism about truth. So long as we remain unchallenged, we proceed on the assumption that things are as we take them to be; when challenged, we may worry that they are not, and that we had better change our way of taking them. So long as we assume that our views had better match reality, we overlook the possibility that, insofar as reality is already plural, there are many ways of matching it.
The challenges we face, which force us to put our views in question, all depend on and express the brute fact of plurality: other people, other versions of ourselves, other situations and concerns, are what stop us in our epistemic tracks. But when a challenge stimulates us to abandon one conclusion and to adopt another in its place, have we not taken an irruption of plurality into our attention-space as reason for switching our loyalty from one kind of monism to another? If so, then it seems the only way to recognize that irruption of plurality for what it is would be to grant foundational respect to plurality itself, thereby no longer seeking to form any set conclusions on the matter.
And that is just the very top of this slippery slope...