Over at The New Republic, Noam Scheiber and Bradford Plumer have started a nice discussion of an important subject that was bound to come up eventually: The similarities between pollution and adultery. Really. It all started with this point from Robert Frank in the New York Times:

A British Web site called Cheat Neutral (www.cheatneutral.com) parodies the concept [of carbon offsets]-- by offering a service under which someone who wants to cheat on his partner can pay someone else who will refrain from committing an act of infidelity. The site's founders say they wanted to use humor to demonstrate why the market for carbon offsets is a moral travesty.

But is this analogy between pollution and adultery really one you'd want to get into bed with?

I wouldn't be too quick! One reason is that I don't necessarily think of the cost associated with consuming fossil fuels as moral. It's a market failure. The issue is that there is a social cost -- an externality -- that isn't internalized by the consumer. Ordinary consumers acting in ordinary, rational ways create the problem. (Is that the case with adultery?) As Brad says: "The problem here is that people who burn carbon don't pay any price at all for those negatives, so the best thing to do would be to slap a price on that externality."

Like Brad, my sense is that there aren't too many environmentalists out there who think there is only one side of this balance sheet -- that is, who are saying "fossil fuels are wicked and you should never use them again." It is important that we continue to use fossil fuels, and I think there are strong arguments that the attendant economic growth is a moral good. The concern is getting people to pay the full social cost of that use. Is that really a moral issue? Or just a practical one?

Of course, a slightly separate question, pace Ross Douthat, is whether porn is like a carbon offset.