DISQUS

Complaining about the actions of past presidents does nothing.

Complaining about the actions of current presidents does marginally more nothing.

There are a vast number of arguments for and against the existence of god. (see http://en.wikipedia.org/wiki/Existence_of_god#A...) I would think the ridiculousness of any or all of them surely would be related to the number of people who accept the conclusion.

I'm not saying I'm persuaded, nor is Douthat saying I should be; but I do think committed atheists ought to take the question a little more seriously, which I think is the only point of Douthat's post.

At no point does in his post does Douthat claim a belief in God to be true. The argument he's making is an agnostic one.

Isn't terrible poet redundant?

Great post, Will

Micha, you'll want to study up on Godwin's Law to avoid derailing a potentially interesting conversation. This thread is officially over and you've officially lost.

Will, thanks for passing along the link to John's essay. I hadn't seen it, and suspect it might just change my life, eventually.

Jim,

Thanks for the timely and civil response. I don't follow your analogy between governments setting carbon taxes and governments setting steel prices. The correct analogy would be to compare setting taxes to setting taxes or setting prices to setting prices. If carbon emissions have a negative externality, placing a tax on them makes economic sense. If steel has a negative externality, placing a tax on it makes sense. In order to support a carbon tax while opposing a steel tax, you only need to argue that carbon emissions have large negative externalities while steel does not.

Reserach shows evidence that carbon emissions definitely have a large negative externality, though the size of the externality varies between studies. No such research exists with regard to steel. The uncertainty created by the variance within the stuides does not negate the evidence they jointly present. Policy-makers should seek to reduce uncertainty by evaluating completed studies and/or implementing new ones, but the lack of precision as to the marginal cost of carbon emission does not support a policy of doing nothing.

Jim Manzi is an accomplished businessman, who he's not an economist, and his arguments aren't very convincing to anyone who is. He claims that a carbon tax is more efficient than a cap-and-trade system, while economists generally see them as identical in efficiency terms, preferring cap-and-trade because it allows policy-makers to precisely set the amount of carbon emitted, its ease of use in international treaties, and to a lesser extent, political feasibility.

Manzi's point 2 claims the social utility created by lower gas prices as an externality, but it is not, since it's captured in the profits of the producer. There is economic incentive to produce cheaper energy, while there is not economic incentive to produce cleaner energy. A carbon tax, or a cap-and-trade system, transfers the social costs of pollution onto producers, such that there is an incentive to produce cleaner energy.

Economists believe there's a certain type of market failure caused by products that have positive or negative externalities, and that government can effectively correct these inefficienies through excise taxes, subsidies, and other policies. Economists see fossil fuels as a product with negative externalities. None of Manzi's arguments counter these points. The fact that marginal costs of emission are hard to calculate should lead to calls for greater study, and a certain degree of care in implementing policy correctly. They don't support a policy of doing nothing.

Human activity's contribution to global warming is not relevant to the optimal tax size. Suppose, for instance, that global warming was occuring naturally, and having a net negative effect on human lives. Human action that reduces natural global warming would then have a positive externality, and should be incentivized to the same degree as if global warming was caused by humans. The question of calculating the net marginal effect of global warming is the important (and difficult) one.