Adam's post got me thinking. It really is a slow week. So, I will take this opportunity to quibble with Adam's misunderstanding of the cow market and PETA's well-intentioned, but ill-conceived scheme to use the tax code to incetivize people to be vegetarians. Adam first. He seems to be arguing two different points. One is that an individual's decision to not eat meat will not reduce the number of cows (and chickens) that will be raised and slaughtered in a given year. I disagree. Let's say you eat one cow a year. If you decide to not eat beef, then at the end of the year, beef producers, after all is said and done, will notice that there's an extra cow hanging out in the feedlot. Next year, those producers will respond by raising and slaughtering one less bovine, and hence fewer greenhouse gas emissions. (An econ 101 textbook will back me up on this.) Adam's second point is that without mass action, the decision to become a vegetarian will not have a noticeable effect on the total output of greenhouse gas emissions. But surely Adam recognizes this same problem in the case of an individual's decision to own a Prius. PETA, though, recognizes this problem. Like the tax credit that has encouraged thousands to buy hybrid vehicles, PETA want to use the tax code to to encourage the mass action that would appreciably reduce greenhouse gas emissions. And this brings me to my quibble with PETA. PETA spokesman Matt Prescott "imagines" some sort of on-my-honor system by which people can attest to their vegitarinism in order to legally claim their tax credit. Adam correctly notes that this sort of system is next to impossible to implement. I would suggest that if PETA wants to use the tax code to achieve its objectives, that it work out something feasible before stepping up to the mic. For instance, it could propose a Pigouvian tax on meat, or, it could agitate for an end to the massive corn subsidies that make beef cheap. My point is simply that using the tax code to create incentives for people to eat less meat, can be a plausible means by which reduce emissions of greenhouse gasses, but it's only going to work if you do it right.