So I've finally been dragged kicking and screaming on to Facebook (thereby rendering it instantly uncool, by the way), and one thing that strikes me is that it is not only a fairly powerful positive force, but also a negative one.
In particular, it enables people with shared views to communicate. This is useful but also poisonous.
Much as been said of the "echo chamber" of modern political discourse, where people of similar views echo each other's sentiments, reinforcing them, and without letting in dissenting points of view. What this does in the human brain is generate an idea of "certainty". And certainty is generally a Bad Thing when it comes to discussing the major problems of the world.
The fact is, shit is complex. World views that refuse to acknowledge that are doomed to fail...painfully, as history has shown time and again.
So modern technology in the form of Facebook allows this process to happen 24/7. And the irony is, those people who most need to listen to other points of view, in order to partially correct their distorted view of reality, are the ones who go out of their way to shut out dissenting voices. All you have to do is click off "Show in my Feed" and you never have to look at it again.
Facebook should remove this feature.