Rivetcounter thought no. 1
It's not the conscious, visible categorising and cataloguing, pattern-seeking and rulemaking that's a problem - it's the fact that it is constantly going on in the background. which pointlessly takes up far too much energy and brain capacity. Do I really need to think every morning about which hand I pick the mugs up of the draining rack with, and therefore what order they go back on their nails? Should I really be bothered about whether I pick my necklace or my earrings first, and worried about how to choose between the pendants that live in little drawers and the beads that live on a rail? My lack of a workable rule for that is bothering me fairly frequently.
I have a new rule, which is that 'preference trumps rules'.
Most of you probably don't need a rule like that.