Are Over- and Underestimation of the Dangers of Global Warming Equally Likely?

Your theory has a problem with survival bias.

The fact that we are here is good evidence that we've experienced a long, long time without disasters.

But in fact, there *have* been severe disasters in history. Let's bear in mind, that while many severe disasters have been predicted and the predictions turned out to be specious, many other predictions did not come to pass, because people *heeded the warnings*.

Talking about thick tails is not the same as doomsaying. No serious climate scientist (few?) is predicting that disaster will happen, only that there is a small chance of disaster (and then only under scenarios that fail to halt CO2 emissions growth within the next 30 or so years). The question is "how small?" and our data and models aren't yet good enough to give a very satisfactory answer.

Even without GHG AGW, these possibilities still exist and probably aren't even much less likely. That makes uneconimical mitigation (regulation) efforts downright ridiculous.

The question of global warming isn't what are we doing to the Earth. The Earth will shake off whatever we throw at it. The question is what are we doing to ourselves, and the cities and towns we live in.

Go to any third world country that's industrialized but doesn't have the kinds of environmental laws we have in the U.S., and you can see how unhealthy unchecked industrialization is. Just look at what China's going through.

We may not destroy the planet, but we can make our own lives very miserable.

It seems to me that although global warming might be a black swan, it's highly unlikely because

1) it's almost a given that you don't see a black swan coming and

2) if positive feedback made the climate highly unstable, I'd expect to see regular cascade-style changes due to natural variation - that is, radical climate change might be rare, but it wouldn't be new. It's not clear to me why the climate would be locally stable (negative feedback) but at some point shift to unstable (positive feedback).

In the end if you're worried about civilization-ending events, I think you want to be as rich and advanced as possible to be able to best deal with surprises.