I appreciate the thoughtfulness of your letter, but it has very little to do with the column I wrote. We are simply addressing different issues. Before I elaborate on that major point, let me mention a few minor points where I think you are mistaken.
First, you argue that past logging has caused unemployment among lumberjacks, and this is evidence that past logging impoverished the current generation. But one could equally well (or equally poorly) argue that electric lighting caused unemployment among candlemakers, and therefore electric lighting impoverished a generation. In both cases, the error is to look at costs while ignoring the offsetting benefits. There might very well have been too much logging in the past, but the current plight of lumberjacks doesn't prove it.
Second, you are surely correct that future generations, because of their increased wealth, will value clean air, wild forests, and natural beauty more than we do. But they will probably value everything else more than we do also, and some of those things require the sacrifice of wild forests. So it's not clear whether on net this means that we should save more forests for them or fewer.
Now to the main point: You argue that wild forests, for example, are underpriced and hence underconserved. There's an excellent chance you're right. But that observation has essentially nothing to do with what I was writing about.
There are two kinds of conservationists in this world. There are those who argue that we should conserve wild forests because their current prices understate their benefits, and there are those who argue that we should conserve wild forests because we have an obligation to improve the lot of future generations. (Of course it's possible to be both kinds of conservationist at once.)
My column was addressed entirely to those in the second camp, pointing out that their rhetoric is inconsistent with the usual rhetoric of income redistribution. You, on the other hand, take a stand (at least in your letter) entirely in the first camp, which seems to me to be on much higher ground.
Steven E. Landsburg