It is easy to say “optimal extinction” and to define it abstractly, in a thread about the benefits of coal burning … but how do you define it in practice? How would you actually target it, if you aren't just using it as a canard?

Basically you mad another ecology-free environmental argument.

It is easy to say “optimal extinction” and to define it abstractly, in a thread about the benefits of coal burning … but how do you define it in practice? How would you actually target it, if you aren't just using it as a canard?

Basically you mad another ecology-free environmental argument.

I didn't define optimal extinction because I thought it was obvious, particularly given my other comments. You choose policy as best you can (from the set of all policies available to us) to maximize present discounted value, and if it turns out that the policy that best achieves that goal involves one species dying out, you call it “optimal extinction”.

Now consider an extreme, very unrealistic example (just as a mental exercise): suppose there were some infinitely lived species that never reproduced at all (so leaving them alone doesn't increase future population) and that had no aesthetic or other value besides eating them. It's very easy to imagine that there would be an “optimal extinction” here (it's basically a nonrenewable resource, and it's not like reasonable people think we should never use them). In fact, if you can scale up your catch cheaply enough, and if the marginal value of the fish doesn't drop off too quickly (or you just expect to be richer and/or have plenty of alternatives in the future), that optimal extinction would be almost immediate.

Now please note that I'm not saying this is a realistic example. But I think it does a pretty good job of laying out the reasons why we would want to preserve a species — e.g., if there are important (and good) interactions with other species or aesthetics or other value that you can get besides eating a fish, if marginal value drops rapidly, if the species grows or reproduces rapidly (or otherwise increases value), etc. And if you extend it, you can see how it's almost certainly not generally the case that the ideal is to shoot for the maximum sustainable yield.

Sorry for the overly long response.

You should have just gone full pun and went with “fueltility”

And the depressing thing is, it may take someone outside the climate field to look at this incisively. Because climatologists must be aware subconsciously that their careers depend on their models not being worthless, even if they have no intent to deceive, I'm sure they inadvertently miss observations that would make catastrophic climate change look less likely.

But I think Dyson, and Wilkinson, and odograph, are missing the point if they think this is a debate about values or ideologies. The reasons I worry about global warming are “humanist” reasons. What if California becomes too dry for agriculture? What if coastlines flood in Bangladesh and Indonesia? What if the Middle East and the Sahel dry up further? What if larger areas of the world become malarial? These are essentially poverty issues, and maybe security issues if resource rivalry leads to war.

The question ought to be “are these scenarios likely? Are they preventable?” and not “what are my politics?” Because if they're likely and preventable, reasonable people of whatever politics will want to prevent them. And if they're not, reasonable people will not want to waste money on a useless effort. It's one of the few issues in policy that I think comes down to an empirical question, albeit a hard one.

Read those and see how well “fishing at the margin” holds up in real oceans.

I think poverty might cut in the opposite direction you're implying, given economic growth. If world poverty rates are declining and average income is increasing (so we expect to have more in the future than today), then that pushes for consuming more today. After all, if we're making an argument about transferring from the rich to the poor, well, future generations are richer than the current one, and since we're already discounting the future …

Except you pulled a fast one on your audience. You called for “optimal extinction” but then made no attempt to define it, or identify the path that would get us there without overshooting the target.

It is the standard half-argument that if there is a limit, we can assume it is way ahead of us, not near enough to worry … presented without input from ecologists of course.