Certain social policy branches conflict and cannot be taken together (eg, Piety and Rationalism). I usually plan ahead to make sure I don't end up wanting conflicting branches, but the other day I did (almost!) activate one to see what happened.
I was given a warning that doing this would cause anarchy for some turns, at which point I stepped back because I was in the middle of a live game.
So, what happens if you activate a social policy for a branch that conflicts with one that you already have active?
Presumably you lose the policies from the conflicted branch, but is this forever?
Or are they hidden in case you switch back later?
Or maybe you get the policies "refunded" and get to transfer them elsewhere?