Thoughts on cryonic preservation & revival

[lproven]

This is a rather long reply to a post from ciphergoth. The question being, is it plausible that, in future, we will be able to resurrect people from their head, cryonically frozen post-mortemI am keenly interested in the prospect of whole-brain emulation, which strikes me as potentially plausible, with reasonable probability. For one thing, I think that this

Comments

[ciphergoth]

I'd like to reply to your points in detail, but just as a general enquiry: if you found that one of the assumptions you've made in your argument in this post was contradicted by existing science, would it cause you to take cryonics more seriously?

[lproven]

Absolutely, yes, and I am keen to know more, especially if I'm wrong or out-of-date.

And in the nature, as someone else put it, of Pascal's Wager, well, if you can afford to do it, then definitely do; there is no real downside.

[ciphergoth]

But Pascal's Wager is a crock - or rather, any system for making decisions that caused you to accept Pascal's wager would be a disaster. If you think that it's as likely to reanimate you as a blessing from a witch doctor, you'd be making a huge mistake to sign up. That's why I've made such efforts to find out if there really is a scientific case against signing up, or whether it's entirely driven by people's difficulties with something so emotionally radical.

[reddragdiva]

FWIW, I don't find it emotionally radical. I find the proffered handwaving the opposite of convincing.

[zotz]

Something that occurred to me a while after reading the good Mr Crowley's thoughts on the matter seems to be confirmed (FSlimitedVO) by thee ackurssed Witchipedia:

Research has suggested that long term memory storage in humans may be regulated by DNA methylation.

That's a real oh-shit problem in my view - getting all the methyl groups right on the dna of at least a good proportion of someone's neurons strikes me as showstopper. DNA methylation not being involved in brain functioning would make the data extraction much easier.

[lproven]

That sort of detail is an area I know next-to nothing about, but I am currently doing some reading in the broad area...

Wouldn't surprise me if you're bang on, though!

[ciphergoth]

Interesting. Is the issue information-theoretic death before you're in the dewar, or a scanning issue?

[zotz]

That one's a scanning issue. Methyl groups are added to individual DNA bases and affect gene expression. They're fairly stable . . . but there are awful lot of potential sites per cell and a lot of neurons, and distinguishing a methylated base from an unmethylated one isn't a trivial task.

[lproven]

Absolutely, yes.

The only cavil is that if you do this for everybody, or more or less everybody, and store all the data just in case, then possibly, /post facto/, one can decide who was a great genius, unappreciated in their time, and bring 'em back later on. This presupposes that data storage continues to get cheaper & cheaper, which is, I think, one of the safest bets in the whole general area under discussion.

Have you read "Learning To Be Me"?

[grendelkhan]

There's a short story by Greg Egan called "Learning To Be Me" from 1990, which seems to explore a very similar idea.

Re: Have you read "Learning To Be Me"?

[lproven]

Actually, yes, I have, which is where I got the basic idea from - but Paul (ciphergoth) is not fond of SF references, so I didn't mention it.

[ciphergoth]

First, many thanks for sharing your thoughts as a stand-alone blog post. This is exactly what my blog post about this was intended to encourage. And it meets three of my criteria at the end of the article!

So I'm hoping you'll take the fourth step, of explicitly discussing the arguments set out by cryonics advocates on the subjects you discuss - you're clearly much better placed to evaluate them than I am. For example, you say:However, the prospects of doing it from a dead brain seem to me to be far closer to 0, in a Zeno's-Paradox sort of way. Once one is outside that critical 4min window of an oxygen-deprived brain, I suspect that the remaining amount of useful information drops precipitately, with every passing minute, and after 2-3x that 4min window, I suspect there isn't enough left to be worthwhile.
I'm guessing you're thinking of ischemic damage? This issue is discussed in detail in Scientific Justification of Cryonics Practice which is the document to rebut if you're interested in this subject. Fahy's cited study on

[reddragdiva]

Yep. Try reading some of the papers he cites and what he says about them too.

[reddragdiva]

Is it possible to go through the tedious work of rebutting it? It is the cryonicists' best shot. Ben Best even showed up on RationalWiki to defend his paper.

(This is the point at which scepticism becomes laborious.)

[ciphergoth]

[1] Getting to the person soon enough after death - I think preservation will need to be done within the same time period that revival would be.

[2] Freezing the brain inside that period, without damaging it - major implementation difficulty here.

[3] Implicit in #2, a preservation method that preserves the structures or patterns that encode the mind in question. Currently more or less impossible to say, as we don't know what structures or patterns those are.

[4] Sampling the result with fine enough resolution to retrieve useful amounts of info.

[5] Finding a way to process, implement or run the resultant dataset in a way that will effectively resurrect the consciousness.
[1] and [2] I've discussed above - it currently looks to me as though existing cryonics best practice will suffice.

[3] Again, I refer you to "Scientific Justification", in particular this bit. If Best is overreaching here that would be an excellent observation to post

[autopope]

I think a reference to Hans Moravec's gedankenexperiment on mind/body dualism is probably worthwhile at this point, if for no other reason than that he suggests an actual protocol for uploading a non-dead (at first) mind (and expands on it at some length in "Robot").

[ciphergoth]

A lot of people find the idea of a Moravec transfer more intuitively plausible than uploading through freezing and scanning. I'm not sure why; while the idea of the former is appealing, it seems to me to require far more advanced technology.