Family is also a common subject of small talk ("How is your wife doing?"), which is identity-plus-plus for most people, and the mating habits of snails are topics most people weakly identify with but not commonly used for small talk, so I'm guessing that relationship is a little less persuasive than it seems to be at first brush.
The real issue is whether the identities conflict. It doesn't hurt my marriage to know that your marriage is great. Meanwhile, knowing someone is a proud follower of the One True Way threatens your identity as a member of the One True-Er Way.
Though if you both happen to be members of the same True Way, starting a conversation about religion and politics can be incredibly beneficial. I know seeing a bunch of Ayn Rand books on a friend's shelf boosted our relationship immensely.
I think what he meant by "weakly identify with" was that people have opinions about these things but aren't hardcore about them. People will identify with the movies they like, what kind of pets they prefer, etc. On the other hand, I feel like very few identify with snail mating at all.
Right, but the thesis is that it is unsafe to even mention identity because it invites catastrophic conversational degradation. The observed ability to talk about family without someone saying uncharitable things about your wife cuts against the thesis.
Both participants need to identify strongly. If two guys strongly identify over the same woman there will be trouble with any talk about her. People fight over sporting teams, but you can ask a fan about the season without conflict if you don't identify with the sport.
Perhaps all that saves these kinds of conversations from spiraling into "religious wars" is peoples' recognition that these things are arbitrary and ridiculous to get upset about.
For instance, I am a dog person and my girlfriend is a cat person. Occasionally, we start to debate the relative merits of each. And there may in fact be one which is in general "better"; after all, most people would agree that dog ownership is better than man-eating tiger ownership. But since we both recognize that dog and cat ownership is a rather silly thing to get upset about, we don't.
On the other hand, politics (for example) are considered to be important. And while we may realize that it's nearly impossible to find a "right answer", that our discussion will likely lead to nothing, etc., we don't feel silly getting upset about it. That, combined with our identity-based connection with politics, leads to flared tempers and out-of-control discussions.
As an extension to what you are saying. Politics and Religion are, in fact, important. Whether or not we give millions to this are that cause, whether there is some kind of afterlife, these are important questions and so people should get involved in them. I think that there is something wrong with people who choose not to. This is not to say that people should be rude or irrational about these topics, but that they should put the thought into them so that they can discuss them rationally, and act on their conclusions in a productive fashion.
That said, I think that HN is generally the wrong place to have these debates. These topics, when treated fairly, require a lot of space and time to flesh out fully, and a tech news forum isn't properly equipped to do that. In addition, they distract from the valuable discussion for which this place is good.
