I tend to avoid having discussions with people on Facebook posts, but mainly because Facebook is a horrible medium for holding discussions. The lack of threaded comments alone is problematic, but the way that it limits posts to a paragraph out of the box makes holding intellectual discussions more unlikely still.

I think everyone has a right to a "safe space" in their blagoblogs, of whatever sort. It's sort of like free speech; you have to defend the free speech you don't like, or find icky, because speech people dislike or find icky is the only kind that needs protecting. Likewise, if I want friends to be able to shut down discussions that make them uncomfortable, I need to acknowledge that others can shut down discussions that might educate them. That's part of how I see it, anyway...