-you think people are idiots when you mention names such as Capablanca, Leko, Carlsen, Giri, Ding, Kasparov, Tal and they don't know who you're talking about.
- you fill with the urge to commit bodily harm when you mention you play tournament chess to a casual acquaintance, and they look at you like you're a different species, and quickly change the subject.
- you know the auto-excuse coming from the mouths of non chess players when they set up the pieces for a casual game is always going to be: "I haven't played in a long time" and your reaction is normally a silent wish that they leave your solar system...now!
- you know you married the right woman when she says things like: "I like that you play chess, smart people play chess"
You might be a chess player when you realise the person you are talking to has finished talking and is waiting for a reply but you've been thinking about that game you finished the other day and haven't heard a word.
You get frustrated whenever there's a brief chess scene in a film/tv show, you can't see the board properly and there's always a checkmate at the end of it.
Also when the word "opening " means something more to you than a gap in a fence.