The power of self-deception

Each year in the U.S., around 42,000 people die in car accidents. We could save all those lives. The only thing we'd have to do is enforce a maximum speed limit of 10 miles per hour or thereabouts. So why don't we do it?

Because we don't consider safety to be infinitely valuable. We trade it off for utility. We sacrifice around 40,000 lives a year in exchange for some gains in convenience, efficiency and wealth; or, more precisely, each driver and passenger accepts certain non-zero risk of dying in a car crash in order to enjoy certain benefits in terms of quality of their life.

It sounds extremely cynical, and it is. It often benefits us to behave in a cynical way. However, most of the time it does not benefit us to admit that we're being cynical, because cynics are perceived (correctly) as untrustworthy in repeat interactions. This is why we've evolved such tremendous capacity for self-deception. When we're making a cynical trade-off, we pretend that there actually is no trade-off--not just to others but to ourselves as well.

Megan McArdle provides an absolutely staggering example of such self-deception at work. The setting is the Congressional Toyota hearings going on right now. McArdle describes an exchange between Representative Mark Souder and Secretary of Transportation Ray LaHood. At some point, LaHood says that his agency considers passenger safety to be priceless. To which Souder replies that this isn't actually true and that we're in fact trading off safety for convenience: if we enforced a speed limit of 30 mph we'd be saving a lot of lives but we don't do it because we recognize that it would make us a lot poorer.

Here comes the amazing part: LaHood disagrees with this, saying that lowering the speed limit to 30 mph would not save any lives, and that this fact is the reason we have minimum speed limits. When Souder reminds him that the actual reason we enforce minimum speed limits is to decrease variance in speeds with which drivers travel, LaHood says: "I don't buy your argument, Mr. Souder".

You might say that this isn't self-deception but outright lying; LaHood understands there is a trade-off but, as a politician, doesn't want to admit it in front of the voters. I doubt it. It is perfectly possible for people (even very smart people) to be sincerely convinced they believe X while at the same time behaving as if they believed something completely different. It's actually easier for a politician to deceive his voters if he's not conscious of the fact that he's lying in the first place. The take-home point of all this is: don't waste your time trying to determine if this or that politician sincerely believes what he says is true. It doesn't matter. Sincerity is overrated.