Comment by TeMPOraL

> The devil is in the details

Only if you care about those details. Almost no one does.

In almost any conversation, everyone does in fact know what intelligence, porn, god and beauty are. Yes, all those ideas are fuzzy at the borders, but we almost never need to resolve them in detail when talking about them. When we do, then yes, things get tricky and there's a lot of disagreement - but at the end of the day, as the phrase I once read on the Internet goes, it all has to add up to normality. You can still work with fuzzy, casual concepts, even though you can't define them precisely.