As utterly anecdotal as this is, it makes me wonder. 

When I’m having a bad day, I tend to notice other people are, too. If I’m being a jerk in traffic (or just rushing - still jerkish, perhaps), I notice others are, too. They seem just as pissed off as I am. 

There are times when I wonder if this isn’t a coincidence, if society is just set up in such a way that our interactions are actually quite related. Bad days are shared overall. Say there’s some overall societal event (bad economy, recent hurricane, overload of negative news being reported on TV, whatever), which puts a damper on the day of 100 people, who then leave in a bad mood. Say another 100 are just plain in a nasty mood for any reason. Then you’ve got the rest of the people who are neutral. Those 200 less-than-positive people are out in society, and maybe they cut off a neutral person in traffic or speak crossly to them. Neutral person gets somewhat annoyed, maybe does it to someone else. It ripples outward.

Everyone arrives at work annoyed. Once you start your day annoyed, it’s pretty hard to turn that around, so everyone just feeds everyone else’s annoyance until we’re all miserable and can go home to say, “I had the worst day today.”

Except those perpetually perky people.

God those people are annoying.

Maybe they’re nature’s balance.