Easy, if you are worried about worse-than-death life after revival, don't get preserved. It's not like there are too few people in the world and no way to create more. I'll take my chances, if I can. I don't expect it to be a problem to self-terminate later, should I want to. I don't put any stock in the scary scenarios where an evil Omega tortures a gazillion of my revived clones for eternity.

A "do not resuscitate" kind of request would probably help with some futures that are mildly bad in virtue of some disconnect between your old self and the future (e.g., extreme future shock). But in those cases, you could always just kill yourself.

In the worst futures, presumably those resuscitating you wouldn't care about your wishes. These are the scenarios where a terrible future existence could continue for a very long time without the option of suicide.

Why am I not signed up for cryonics?

Here's my model.

In most futures, everyone is simply dead.

There's a tiny sliver of futures that are better than that, and a tiny sliver of futures that are worse than that.

What are the relative sizes of those slivers, and how much more likely am I to be revived in the "better" futures than in the "worse" futures? I really can't tell.

I don't seem to be as terrified of death as many people are. A while back I read the Stoics to reduce my fear of death, and it worked. I am, however, very averse to being revived into a worse-than-death future and not being able to escape.

I bet the hassle and cost of cryonics disincentivizes me, too, but when I boot up my internal simulator and simulate a world where cryonics is free, and obtained via a 10-question Google form, I still don't sign up. I ask to be cremated instead.

Cryonics may be reasonable for someone who is more averse to death and less averse to worse-than-death outcomes than I am. Cryonics may also be reasonable for someone who has strong reasons to believe they are more likely to be revived in better-than-death futures than in worse-than-death futures. Finally, there may be a fundamental error in my model.

This does, however, put me into disagreement with both Robin Hanson ("More likely than not, most folks who die today didn't have to die!") and Eliezer Yudkowsky ("Not signing up for cryonics [says that] you've stopped believing that human life, and your own life, is something of value").

Eliezer, thank you for writing a beautiful post. I do hope that the people of the future value my life more than the people of the present, and the fact that there is at least two people in the present who do (Eliezer and my mom ;-) ) is heartening.

I am quite convinced about cryonics in general, but I am not convinced at all that paying up right now for CI or Alcor is a smart investment. What's the downside of just setting aside enough money for cryopreservation and choosing the best option when death looms?

Consider:

• I am 27. If I die suddenly (without regaining consciousness even for a day) in the next decade it's likely that I would die in a fashion (shot in the head, car crash) that won't leave much of my brain to be preserved.

• The chances that I'll be in the US when I die are very far from certain (I'm a foreign citizen living in NYC currently).

• If I decide a decade from now that I don't want to cryopreserve, the fees would have been money wasted. I can't force me-in-10-years into a decision.

• Judging by the progress of modern medicine (advances in cancer treatment) and my family history (pretty good from a cardiovascular standpoint) it is very likely that my ticket out will be Alzheimer's or another neurodegenerative disease. In that case, cryopreservation will only make sense if I commit suicide at the very onset of the disease and am frozen right away which may not be possible. If I get Alzheimer's I may as well donate all my money to SIAI or Africa.

• If the future is going to move in the direction we are hoping to, it's not unlikely that there would be more companies offering cryopreservation with better deals (e.g. lower fees, global coverage, eternal investment trust management).

Basically, what is the upside of signing up for one specific company and paying the fees vs. knowing that I have made the decision to spend the money on cryopreservation instead of life-prolonging treatment and trusting my future cancer-diagnosed self to be brave enough to keep it?

I actually had a nightmare recently where I was diagnosed with an aggressive cancer and would have preferred not to go through treatment, but felt pressured by other, more aggressively anti-death members of the rationality community. Was afraid people would think I didn't care about them if I didn't try to stay alive longer to be with them, etc. (I'm an ICU nurse; I have a pretty good S1 handle on how horrific a lot of life saving treatments are, and how much quality of life it's possible to lose.)

I've thought about cryonics, but haven't made a decision either way; right now, my feeling is that I don't have anything against the principle, but that it doesn't seem likely enough to work for the cost-benefit analysis to come out positive.

Science has moved away from considering memories to be simply long-term structural changes in the brain to seeing memories as the products of "continuous enzymatic activity" (Sacktor, 2007). Enzyme activity ceases after death, which could lead to memory destruction.

For instance, in a slightly unnerving study, Sacktor and colleagues taught mice to avoid the taste of saccharin before injecting them with a PKMzeta-blocking drug called ZIP into the insular cortex. PKM, an enzyme, has been associated with increasing receptors between synapses that fire together during memory recollection. Within hours, the mice forgot that saccharin made them nauseous and began guzzling it again. It seems blocking the activity of PKM destroys memories. Since PKM activity (like all enzyme activity) also happens to be blocked following death, a possible extension of this research is that the brain automatically "forgets" everything after death, so a simulation of your brain after death would not be very similar to you.

http://www.nimh.nih.gov/science-news/2007/memory-sustaining-enzyme-may-help-treat-ptsd-cognitive-decline.shtml

Not all of what makes you you is encoded in the physical state of the brain (or whatever you would have preserved).

This is probably true, isn't it? Most of what makes you, you, is in your brain, but another large part of it is mediated by hormones going to and from the rest of your body... I think. Yet most LWers who are into cryo go the 'neuro' route. Is there some reason why this consideration is not nearly as big a deal as I think? Is the idea that making a 'spare' human body is cheap?

Upvoted the post. Worthy thing to discuss.

A reply to kalla724 that you did not mention is here: http://lesswrong.com/lw/d4a/brief_response_to_kalla724_on_preserving_personal/

Kalla724 claims that it is not possible to upload a C. elegans with particular memories and/or behaviors. I think that this is a testable claim and should shed light on kalla724's views on preserving personal identity with vitrification. I also think it is likely wrong.

Example: Edward Boyden, Assistant Professor at the MIT Media Lab, recommends recording in a notebook every conversation you ever have with other people.

The link goes to Prof. Boyden's university profile, which doesn't mention his note-taking habits. This is all I could find after spending five minutes on Google:

"He was doing three students' worth of work," says Raymond. "Every moment of his day [is] action-packed." Both his advisors recall with a laugh Boyden's habit of taking notes on all his conversations and ideas. "He does this, so far as I can tell, every waking moment," says Raymond.

Does anyone here know where more information about Boyden's approach is to be found?