I find that about as convincing as "if you see a watch there must be a watchmaker" style arguments.

I don't see the similarity here.

There are a number of ways theorized to test if we're in various kinds of simulation and so far they've all turned up negative.

Oh?

String theory is famously bad at being usable to predict even mundane things even if it is elegant and "flat" is not the same as "infinite".

It basically makes no new testable predictions right now. Doesn't mean that it won't do so in the future. (I have no opinion about string theory myself, but a lot of physicists do see it as promising. Some don't. As far as I know, we currently know of no good alternative that's less weird.)

As yet we have ~zero evidence for being in a simulation.

We have evidence (albeit no "smoking-gun evidence") for eternal inflation, we have evidence for a flat and thus infinite universe, string theory is right now our best guess at what the theory of everything is like; these all predict a multiverse where everything possible happens and where somebody should thus be expected to simulate you.

Your odds of waking up in the hands of someone extremely unfriendly is unchanged. You're just making it more likely that one fork of yourself might wake up in friendly hands.

Well, I think that qualifies. Our language is a bit inadequate for discussing situations with multiple future selves.

you can somewhat salvage traditional notions of fear ... Simulationist Heaven ... It does take the sting off death though

I find the often prevalent optimism on LW regarding this a bit strange. Frankly, I find this resurrection stuff quite terrifying myself.

I am continuously amused how catholic this cosmology ends up by sheer logic.

Yeah. It does make me wonder if we should take a lot more critical stance towards the premises that lead us to it. Sure enough, the universe is under no obligation to make any sense to us; but isn't it still a bit suspicious that it's turning out to be kind of bat-shit insane?

Of course not. But whether people here agree with him or not, they usually at least think that his arguments need to be considered seriously.

I don't believe in nested simulverse etc

You mean none of what I mentioned? Why not?

but I feel I should point out that even if some of those things were true waking up one way does not preclude waking up one or more of the other ways in addition to that.

You're right. I should have said "make it more likely", not "make sure".

I think the point is that if extinction is not immediate, then the whole civilisation can't exploit big world immortality to survive; every single member of that civilisation would still survive in their own piece of reality, but alone.

By "the preface" do you mean the "memetic hazard warnings"?

Yes.

I don't think that is claiming that it is a rational response to claims about the word.

I don't get this. I see a very straightforward claim that cryonics is a rational response. What do you mean?

This is a quantum immortality argument. If you actually believe in quantum immortality, you have bigger problems. Here is Eliezer offering cryonics as a solution to those, too.

I've read that as well. It's the same argument, essentially (quantum immortality doesn't actually have much to do with MWI in particular). Basically, Eliezer is saying that quantum immortality is probably true, it could be very bad, and we should sign up for cryonics as a precaution.

Perhaps you shouldn't. That said, it is recommended by Eliezer Yudkowsky, and his words often weigh quite heavily here.

I don't necessarily agree that lacking experimental verifiability means that we shouldn't take something into account when making decisions, if we have enough reasons to think that it's true nevertheless.

I don't think so, with the slight change from "QM is wrong" to "QM is limited in its applicability, just like Newtonian physics".

Fair enough. I suppose one could say that the problems with combining QM and general relativity suggest that QM needs to be modified, but so far we don't have experimental evidence for anything but pure QM, I believe.

But in any case, in this thread you operate in a black-and-white world of "zero probability" and "non-zero probability". I am pointing out that the set of zero-probability events is empty.

Well, our discussion spun off from a comment where lisper claimed that surely there are situations where death is inevitable. I countered by saying that as far as I know, there's always some way to survive that has a non-zero probability according to quantum mechanics, so that's where the emphasis on zero vs non-zero probability originally came. Note that the view advocated in the original post views the formalism of quantum mechanics as an accurate description at all scales and also says that all events with a non-zero probability will happen (but that the ones we end up not observing are not something we should care about).