Sunday, April 12, 2009

Elastic replacement

I've been thinking on an off for several years about the concept of 'elastic replacement.' That is term I made up to mean when the rate at which new things arise increases in response to the effort to remove old things. The example that got me started thinking about this was a political one. For the early years of the US occupation of Iraq, the Bush administration frequently cited statistics on how many terrorists had been killed or captured as a result of US action in Iraq. What they never seemed to consider was that US action in Iraq might also be increasing the replacement of terrorists by making it easier for terrorists to find and recruit young people who might have otherwise been non-violent. The size of any population is determined by not only the number leaving, but also the number entering, and by measuring only one portion of our effect, the US government necessarily got a biased picture of our effect. The CIA has confirmed that the number of active terrorist in Iraq rapidly increased rather than decreasing through the first years of the Iraq war.

This general idea carries over into all sorts of arenas. When a giant old tree falls, it makes space for hundreds of seedlings. When I comb my cat to remove loose hairs, I loosen lots more hairs and possibly even stimulate increased hair growth. WWII caused far fewer deaths of US soldiers than the ensuing baby-boom caused births of US babies. Eating all the chocolate so that my wife won't be tempted by it inspires her to go out and buy more chocolate. Responding to all the emails I should have responded to a long time ago brings in even more emails that need to be responded to.

Elastic replacement seems to be an extremely common class of unintended consequences. Humans don't seem to be good at considering it, but we should try.


jte said...

"Elastic replacement" is a great term, but how does it differ in whole or part from "feedback mechanism"? Ignoring replacement is sometimes the result of human failure, no doubt, but also sometimes the result of conscious decision deriving from political calculation.

Dan Levitis said...

Elastic replacement is a type of feedback mechanisms. The feedback you get from holding a microphone too close to the speaker is not elastic replacement. If I go to a restaurant, and the food is terrible, and I don't go support that restaurant again, that is a feedback mechanism, but it isn't elastic replacement. But if a terrible restaurant goes out of business, thereby making space for a better one, that is a feedback mechanism that would qualify as elastic replacement.