I also found this blog through HP:MoR.
My ultimate social value is freedom, by which I mean the power of each person to control their own life. I believe in something like a utilitarian calculus, where utility is freedom, except that I don’t really believe that there is a common scale in which one person’s loss of freedom can be balanced by another person’s gain. However, I find that freedom is usually very strongly positive-sum on any plausible scale, so this flaw doesn’t seem to matter very much.
Of course, freedom in this sense can only be a social value; this leaves it up to each person to decide their own personal values: what they want for their own lives. In my case, I value forming and sustaining friendships in meatspace, often with activities centred around food and shared work, and I also value intellectual endeavours, mostly of an abstract mathematical sort. But this may change with my whims.
I might proselytise freedom here from time to time. There would be no point in proselytising my personal values, however.
It may still be negative-sum, but at least it’s really win-lose instead of lose-lose.