I wanted to try and write this like a sequence post with a little story at the beginning because the style is hard to beat if you can pull it off. For those that want to skip to the meat of the argument, scroll down to the section titled ‘The Jealous God of Cryonics’
The year is 1600BC and Moses is scrambling down the slopes of Mount Sinai under the blazing Egyptian sun, with two stone tablets tucked under his arms - strangely small for the enduring impact they will have on the world. Pausing a moment to take a sip of water from his waterskin, he decided to double-check the words on the tablet were the same as those God had dictated to him before reading them to the Israelites – it wouldn’t do to have a typo encouraging adultery! Suddenly, a great shockwave bowled Moses onto the ground. It was simultaneously as loud as the universe tearing itself into two nearly identical copies, but as quiet as the difference between a coin landing on heads rather than tails. Moses - trembling with shock - picked himself up, dusted off the tablets and scratched his beard. He was sure that the Second Commandment looked a bit different, but he couldn’t quite put his finger on it...
More than three thousand years later, Blaise Pascal is about to formulate the Wager that would make him infamous. “You see,” he says, “If God exists then the payoff is infinitely positive for believing in Him and infinitely negative for not, therefore whatever the cost of believing you should do it”.
“Well I’m sceptical,” says his friend, “It seems to me that the idea of an infinite payoff is incoherent to begin with, plus you have no particular reason to privilege the hypothesis that the Christian God should and wants to be worshipped, and not to mention the fact that if I were God I’d be pretty irritated that people pretended believe in Me because of some probabilistic argument rather than by observing all of My great works”
“But don’t you see?” Pascal rejoins, “God in His infinite goodness foresaw your objections and wrote the Second Commandment specifically to take that into account; ‘Thou shall have no other God but me, unless thou feels that thy can maximise thine’s utility by ignoring this Commandment and worshipping multiple Gods. Seriously, I don’t mind, worship as many Gods as you want with whatever degree of ‘true’ faithfulness versus rational utility maximising makes you happiest (although I recommend worshipping only Gods that do not prohibit the worship of other Gods, so as to maximise your chances of getting it right and going to heaven)’ “
“Hmm... Yes, come to think of it there has always been something a little different about that Commandment compared to the rest. I didn’t think much of it because there exist similar laws in every other major religion, which now I reflect on it should probably have tipped me off to the format of your Wager quite a long time before now”
“You see my Wager suggests you should worship the largest subset of non-contradictory Gods you possibly can; although I acknowledge that the probability of selecting the true God out of all of God-space is small (and for that God to both exist and select for heaven based on faithfulness is also unlikely), the payoff is sufficiently wonderful to make it worth the small up-front cost of most religions’ declarations of faith. I can only imagine what sort of a fanatic would seriously propose this argument in a Universe where all Gods demand you sample only once from God-space!”
In the universe Pascal describes, all you need to do to qualify for eternal life given a particular religion is true is to say out loud that you are a true believer (or go through some non-traumatic initiation rite, like a baptism or Shahadah). The probability of a God existing is still low, and the probability of that God caring that you worship Zir is still low, but it is (almost certainly) rational to take the advice of Pascal and find a maximal subset of Gods that you think maximises your chance of eternal happiness.
The Jealous God of Cryonics
Cryonics is not like Pascal’s Wager except superficially, but this little story attempts to drive an intuition which would appeal to bizzaro-Pascal. In this universe, someone who worshipped only one God would be deeply irrational. They might be able to defend their choice with some applause-light soundbites (“I have great faith, so I need no other Gods”) but in a purely utility-maximising sense - the sense where we try and maximise the number of happy years we live – this person is behaving irrationally. But although this seems obvious to us, some (most) cryonics advocates behave as though cryonics is a ‘jealous’ God (like in our universe) rather more accurately modelling it as a ‘permissive’ God like in bizzaro-Pascal’s universe. Cryonics doesn’t care at all if you adopt other strategies for maximising your lifespan except insofar as they conflict with cryonics. So for example high religiosity and cryonics are logically compatible as far as I can see; if brain death really is death (that is to say it is completely irreversible) then at least you have the back-up possibility that an afterlife exists. Yet it seems to me that supporters of cryonics happily stop looking for alternate life-extension strategies almost as soon as they discover cryonics (I hypothesise the actual mechanism is that someone convinces them cryonics is rational and then they forget about the rest of the strategy-space in their excitement). Certainly, I can’t find any discussions on cryonics on LessWrong promoting any alternate life-maximisation techniques except perhaps brain plasticisation. This is a shame, because it is possible that some additional life-extension techniques might be costlessly employed by those who want to live forever to greatly increase their expected utility.
Looking around for literature on this topic. Alcor, for example, have an article entitled ‘The Road Less Travelled’ talking about potential alternatives to cryonics including desiccation and peat preservation. Brain plasticisation and chemical preservation are seriously discussed as alternatives even amongst those who are strongly in favour of freezing; the consensus is that these techniques are likely to offer a higher success rate once they are perfected, but freezing is the way forward now. I can think of a few more outlandish methods of preservation (such as firing yourself into the heart of a black hole and assuming time dilation means you will still be alive when a recovery technique is developed or standing in a high-radiation environment hoping that your telomerase will re-knit) but these all suffer from the fact they are less likely to work than cryonics, and obviously so. Why would cryonicists waste time thinking about outlandish preservation techniques when they displace a more likely technique? Indeed, even if these techniques were more likely there are good reasons to treat cryonics as a Schelling point unless a new technique obviously dominates; we want future society to spend all of its resources targeting one problem, especially if we are part of the generation that is first experimenting with these techniques. While it surprises me that no cryonicists seem interested in this even as an intellectual exercise, it is at least rational to ignore low-probability techniques which displace higher-probability techniques with the same payoff for all of the above reasons.
The Extended Strategy-Space
But there seems to be no excuse for failing to consider additional strategies which complement cryonics; there exist a very great number of strategies which could be followed that might result in revivification before cryonics (or instead of cryonics if cryonics turns out to be impossible) and have a cost of strictly less than cryonic freezing. I’ve given them short descriptions to enable easy reference in the comments (if anyone is interested) so don’t read too much into the names. I’ve also ordered them roughly in the order in which I find them plausible; up until the boundary between Social and Simulation Preservation I actual find the arguments more plausible than cryonics:
- Diarist Preservation: Begin recording your phone calls, pay someone to archive your web presence, begin keeping obsessive diaries and blog constantly. Hope that this can be recompiled into a coherent personality at some point in the future, or at the very least be used to plug gaps in the personality of the unfrozen body.
- Genetic Preservation: Take genetic samples of yourself and preserve them in a platinum-iridium bar in binary. Hope that personality is very largely genetic, and the proportion that isn’t can be reconstructed from statistical analysis of the time period in which you live (perhaps by employing Diarist Preservation in tandem).
- MRI Preservation: Subject yourself to MRI scans as often as possible (it may be helpful to fake a serious neurological condition). Ask for copies and encode them in microchips that you scatter round the world as you travel. Hope that future societies will find the information useful to constructing an em and will find the chips if they are distributed widely enough.
- Signal Preservation: Obsessively generate long streams of nonsense binary based on tapping randomly at a keyboard. Assume that these long strings must correspond in some way to brain states, and that future mathematics will be advanced enough to untangle the signal from the noise. Post these long strings of text to as many internet sites as possible to preserve them (VERY VERY IMPORTANT NOTE: If you decide to try this strategy you must absolutely ensure that the first few characters of every message are a code known only to you salted with (for example) the current time and then hashed, or the first word of the next string of binary you produce. Otherwise unkind people could claim to be you, post their own strings and screw up your revival. I don't think it is a serious worry that people who can bring you back from the dead will struggle with SHA)
- Social Preservation: Form a hypothesis which says (roughly) “The more people who know about me that I can persuade to freeze their brain information with me, the more likely it is that any gap in my own brain-state can be plugged with information from another individual’s brainstate”. Act ruthlessly on this hypothesis; pay for friends and family to get frozen conditional on their memorising a list of facts about you. Offer to discount a friend’s cryo in exchange for them signing up with another organisation to you (in case yours has a damaging but not fatal mishap and you need perfectly-stored redundant information to back yourself up). Attend cryonics conferences like a vulture, and socialise as much as you possibly can. An additional note about this strategy (which every pro-cryonicist knows); it is hugely in your interest to take a large 21st Century contingent with you to whatever time you are revived, so that your 21st Century contingent can form a natural political bloc. Even better if the majority of that bloc know and like you!
- Simulation Preservation: Bury ‘time-capsules’ – lead-lined containers which explain in as many languages as possible who you are and expressing a desire to be resurrected if society has discovered that we live in a simulation and has the power to talk to the simulators. Otherwise ask the society to rebury your letter (after translating the request into all current languages) to await the arrival of a true simulationist society. A stronger version of this is to employ one of the aforementioned Preservation techniques and add in your letter that you would be happy to be resurrected inside a simulation created by this society based on the information preserved by that technique; that insures against the possibility that simulation is logically possible but we have not yet discovered a way to communicate with the simulator.
- Philosophical Preservation: Discover a completely watertight argument which proves – perhaps probabilistically - that ‘you’ (the bit of you you hope will survive death) is totally identifiable with something permanent like the information on your Y-chromosome (for men) or the unordered atoms in your brain. Do whatever this argument implies to extend your life. This might sound silly, but many people really do profess to believe their ‘soul’ survives forever and they can increase their chances of this occurring by correctly interpreting a very old book, so it is highly likely that there is an argument that would convince you, even if that argument is not actually valid. A clever rationalist might even be able to identify a subset of religious/philosophical activities that maximises their chance of eternal life in heaven (as per the introductory story).
- Evolutionary Preservation: Blast genetic samples of yourself into space. Hope that eons later one sample will come to rest on a planet suitable for life and evolve into a creature identical to you except whereas you have mostly true beliefs, this creature will have mostly delusional beliefs that correspond in a one-to-one way with your true beliefs. For example while you truthfully think, “I was alive in 2010”, this creature will have a delusional belief, “I was alive in 2010”, plus whatever additional delusional beliefs it needs to make this belief cohere, for example, “I must have been stunned sometime in early 2070 (when my beliefs appear to stop) and taken to this strange planet I don’t recognise”.
- Time-travel Preservation: Do something so marvellous or heinous that if time travel exists, some time travellers will travel to the moment of your triumph/crime to watch. Overpower a time traveller, and take their time machine. You might have a very low prior probability of being able to do something so brilliant/evil as to compete with the whole rest of history, but bear in mind the first successful hijack of a time machine would itself be an event worth watching by future time travellers, so you may not actually need to do anything marvellous in the first place; just make a binding resolution with yourself to steal the first time machine you come across and look to see if any police phone boxes pop up from nowhere. Making this resolution once or twice a day for the rest of your life is almost costless, although perhaps you would want to attend a combat sport class to increase the chances of a successful overpowering.
Each of these strategies have a number of features which make them attractive; they are (mostly) less expensive than cryonics, they do not strictly lower your chance of cryogenic revival (and in some cases probably increase it) and all have a non-zero chance of preserving your brainstates at least until future society is advanced enough to do something with them. Even better, most of these strategies synergise well with each other; if I decide to get myself frozen I will definitely also pay for fMRIs to record my brainstate as I think about various stimuli and store copies of those recordings with multiple institutions. I don’t think this list is exhaustive, but I do think it covers a good amount of the possible ‘live forever’ strategy space. It does not explore strategies which are absurdly expensive or which interfere with cryonics - so it is still only one small corner of the total strategy space – but I think it expands the area of the strategy space most people are interested in; the bit in which you and I can act.