Willful Ignorance

Religion and politics don't typically make good workplace discussion topics. Especially religion. Why not? A major reason is that our religious beliefs are tightly bound up with our individual identities. Therefore, when our beliefs differ from others, we tend to think of the situation as "I'm right and you're wrong." Even if no one says that explicitly, there is an implicit challenge to your beliefs when someone expresses their own.

This causes tension.

In fact, I think this tension is a big reason why we don't talk about religion with friends that don't share our beliefs. We think it will get in the way of our friendship by offending one or both of us. Yet if knowing someone believes differently than you causes offense, it must be because you care about what they think about your religion (and in some way you). And if you care about what they think, then shouldn't you try to find out what they think? And yet that requires you to talk about religion, the very thing we are avoiding by choice.

If this is the case, it may be that we actually don't care much what our friends think about our religion. But if we don't care, then we wouldn't bother purposely avoiding it. I think it is more likely that we hit a psychological snag when these things are discussed openly. We no longer have plausible deniability. Before it is discussed openly, we hold convenient assumptions about their beliefs so we can think about how much fun we have otherwise. After, we can think of little else.