When something is wrong on the Internet, bloggers love to pounce. But since no blogger is infallible, most of us can find ample fodder in our own past writing, if we go back and reread it with a sufficiently critical eye. Over the next few weeks, I plan to revisit some things I got wrong the first time around. (You’ll recognize those posts by the Homer Simpson logo.) I hope others will be inspired to do the same.
To lead off this series: In December, 2009 I blogged about space scientiest James Hansen, who prefers carbon taxation to cap-and-trade. His argument: A carbon tax allows for the possibility of additional carbon abatements through altruism. Under cap-and-trade, if I altruistically decide to buy a fuel-efficient car, someone else gets to buy an SUV. Whereas under a carbon tax, if I altruistically decide to buy a fuel-efficient car, less gas gets consumed.
Wait a second, though. Under a carbon tax, if I decide to buy a fuel-efficient car, I drive the price of gas down, which encourages someone else to buy an SUV. So altruism is equally ineffective under either policy, no?
That’s the argument I made in December, 2009. I now believe that:
- Under a plausible interpretation of Hansen’s argument, I was wrong.
- But Hansen is still unconvincing, though for somewhat subtler reasons.