David Weinberger quote from Spark a few weeks ago about conversations

There is, I think, a hidden assumption in those who critique the internet overly, for allowing us hang out with people who are like us. I completely acknowledge that that is a real danger. It's one of the greatest drawbacks and dangers of the internet: that we do as humans seem to prefer to hang out with people who believe what we believe, reconfirm what we believe. It's just much easier, simpler and more fun to do that. That is a real danger, so I don't mean to diminish that. However, it's also important, I think, to keep in mind just how much agreement we need in order to have a simple conversation.

So, the old enlightenment ideal was you could take two people who profoundly disagree, sit them down, preferrably in a coffee shop, let them talk honestly and openly and both open to the other side, and if they are at it long enough and are good-hearted enough, well-intentioned enough, they will come to agreement. That ultimately we will come to agreeement.

First of all, I think the net shows that that's not true: that we are in fact never, ever going to agree on anything. And the hope that we will, it's a hope that we have to give up on. We are not going to agree on everything. Even things where other people are wrong, they're just factually wrong, they're not going to change, you're not going to get them to agree. And second of all, that sort of coffee shop conversation is bascially impossible. In order for us to converse we have to be speaking the same language, be interested enough in the same thing, that we're willing to converse, have enough assumptions in common that we're able to meet and move forward. Conversation needs so much agreement. That may be unfortunate, but it is the way conversation is.

Spark 167, 38:54-40:44

(emphasis mine)