A couple of people have linked Lance Arthur‘s interaction with a guy trying to cut in an iPhone line:

…I turn around and find a stranger standing behind me. Certain, he is nothing at all like the young Asian girl I was joking with for precious hours of my life. And the game commences.

“Are you standing in line?”

“Yeah.”

“Were you standing in line behind me outside for three and a half hours.”

“Yeah, I was.” Grin.

He stares at me. I instantly hate him. A lot. I hate everything about his self-congratulatory smart-assed grin and his cheating little heart and his idea of how life should work for him, where he can outsmart us all and get what he wants and get away with it. “No, you weren’t.”

“Yeah, I was.”

I point out to the front of the store. “She was behind me in line. You weren’t.”

“Are you gonna tell on me?” He asks this while still grinning that grin. I want nothing more than to kill him with something sharp.

“I am.” I start looking for someone to tell.

“How does it hurt you?”

It’s a great statement of the problem. These people infuriate us: we want them to suffer for their violation of the rules, even if bringing this about hurts us too. (Read the comments if you want empirical support for that.) But Line Jumper has a point: cutting in doesn’t hurt Lance, who would be better off, absent his rage, if he ignored Line Jumper rather than investing energy in making a scene.

So it looks like a case where anger motivates irrational action– irrational, that is, by the cool calculations of the egoist, or something like this. One game-theoretic justification for patterns of anger responses goes like this: if you’re the kind of guy who gets angry, you might find yourself in situations where you want to sacrifice your interests to hurt the person who hurt you, because that’s what anger motivates you to do– it gets you to value (temporarily) the other person’s suffering over your own coldly-assessed well-being. That’s bad, but, on the other hand, if potential aggressors know that you’re this kind of guy, they won’t aggress against you in cases where they would aggress against those who coldly consider their interests before deciding to retaliate. “Don’t mess with that guy, he’s crazy” is the short version. (In The Strategy of Conflict Thomas Schelling makes a lot of the way in which apparent liabilities, e.g. irrationality, can be assets, and this is a case in that general area. Another good read on the emotions case in particular is Robert Frank’s Passion Within Reason.)

The upshot is that it’s beneficial to have traits that are suboptimal in particular instances, especially if having the trait prevents most of those instances from occurring. (The ‘paradox of deterrence’ works this way: suppose only a sincere intention to counterattack prevents an aggressor from striking first, but a counterattack would be morally unjustified. Thus it looks like there’s a moral reason to adopt an immoral intention. Zing!) The twist here is that Lance himself isn’t the one benefitting in this direct way. If I knew anything about this I’d bet that a willingness to get angry (e.g.) is a way of not being a free-rider, and the best way to signal that is to actually have the relevant anger policy.

The horrible, horrible irony is that I’ve talked myself into being more like my mother. She loves to see aggressive drivers ticketed, for example. “What’s it to you?” I used to ask, because I found it petty. But I endorse norms that prohibit aggressive driving– partly on anti-free-rider grounds, because aggressive drivers are making others do the work of accident-avoidance– and if I do that I have to put my emotional money where my mouth is.

Via Drum and Healy.