A subtle problem for predicting the future comes from Martyn Smith, who reminds us about the formation of new subcommunities. Smith is considering the Reformation:
We could lose ourselves examining the doctrinal details of the various camps (Calvinism, Lutheranism, Counter-Reformation Catholicism), but that would miss the sociological point: we are witnessing in all this talk the rise of new community boundaries, which break along lines that could not have been predicted beforehand.
I'm reminded of science fiction examples of doing this well, like the first couple of Foundation books.
Note that once these Black Swans appear, they get naturalized by repeated practice: