Why the Viaduct Makes You Stupid

Over on the online science salon The Edge, Daniel Kahneman talks about the difference between inside and outside views in decision-making. People are prone to taking the inside view, he says:

The inside view is looking at your problem and trying to estimate what will happen in your problem. The outside view involves making that an instance of something else -- of a class. When you then look at the statistics of the class, it is a very different way of thinking about problems. And what's interesting is that it is a very unnatural way to think about problems, because you have to forget things that you know -- and you know everything about what you're trying to do, your plan and so on -- and to look at yourself as a point in the distribution is a very unnatural exercise; people actually hate doing this and resist it.

In taking the outside view, special characteristics are not considered -- you're mapping the whole "ballpark" and that's the advantage. You're less likely to weight specific factors for or against, like your possession of superhuman strength and ingenuity, and so your estimate of the total cost, say, is more likely to end up within the ballpark even if things go wrong.

We're all "over" talking about the Viaduct, but if you look over the literature, it's largely been an argument between people adopting an outside view (citing similar cases) and exceptionalists like #8 for whom nothing is more alike than it is different:

also, they’re lying about san francisco and how the embarcadero compares to 99. no, our city isn’t more special, but i’m sick and fucking tired of you fucking pretending that we already have transit like every other city you care to cite, or that 99 is a spur highway for casual use like the embarcadero.

Kahneman's outside view is counter-intuitive, as he says. But to argue it, you need to take the counter-intuitive step of adopting it. It's useless to argue special characteristics when people are talking about the class of "cities that have downsized transportation infrastructure and lived to tell the tale." The counter-argument has to be the class of "cities that downsized transportation infrastructure and saw Armageddon."

It's a bit like the difference between knowing the probability of hands in a poker game, and betting against what you think is Fred's tell. We're gamblers at heart, addicted to the notion of agency, binary positions ("It'll be heaven on earth!" or "No, it'll be hell!"), and inside info's upper hand. Taking the outside view sucks all the romance out of being right. It gives you less to argue passionately about, and as a blog we -- oh shit -- forget the whole thing. Seattle is different!