Like many people I am afraid of dying, more afraid as I get older and death gets closer. Are there ways I might avoid it?
I can think of four, all possible, none likely. Two depend on my doing something, two on getting lucky, three on technological progress that may happen but probably not in time for me.
Solving the Aging Problem
On the face of it, aging looks like poor design. We have been selected by evolution for reproductive success; the longer you live without serious aging, the longer you can keep producing babies. Even if you are no longer fertile, staying alive and healthy allows you to help protect and feed your descendants.
The obvious answer is that if nobody got old and died there would be no place for our descendants to live and nothing left for them to eat. But that confuses individual interest with group interest; although group selection may have played some role in evolution, it is generally agreed that the major driving force was individual selection. If I stay alive, all of my resources go to help my descendants; insofar as I am competing for resources, I am competing mostly with other people's descendants. Besides, we evolved in an environment in which we had not yet dealt with other sources of mortality, so even if people did not age they would still die, and on average almost as young. In traditional societies, only a minority lived long enough for aging to matter.
A second possible answer is that immortality would indeed be useful, but there is no way of producing it. Over time our bodies wear out, random mutation corrupts our genes, until at last the remaining blueprint is too badly flawed to continue to produce cells to replace those that have died.
This answer too cannot be right. A human being is, genetically speaking, massively redundant — every cell in my body contains the same instructions. It is as if I were a library with trillions of copies of the same book. If some of them had misprints or missing pages, I could always reconstruct the text from others. If two volumes disagree, check a third, a fourth, a millionth. Besides, there are organisms that are immortal. Amoebas reproduce by division — where there was one amoeba, there are now two. There is no such thing as a young amoeba. (from my Future Imperfect, Chapter XVII.)
If that argument is correct and if we continue to learn more and more about biology, at some point it should be possible to slow, eventually to reverse, human aging, to rebuild a body.
We already do it on a small scale. A scratch on a car does not heal. A scratch on my arm does.
So one way in which I could avoid death, at least for a very long time, is if I get lucky, if the aging problem is solved before it kills me. Even a partial solution, a way of slowing aging, might keep me alive long enough for the secret to reversing aging to be found.
It is an encouraging thought but I doubt progress will be fast enough for me. For my children, probably.
Cryonic Suspension
You can, at a price, arrange for the Alcor Foundation to freeze you, infusing your body with cryoprotectant to prevent the formation of damaging ice crystals, a technology already used to freeze organs for later transplant. Alcor guarantees to do its best to keep your body at a very low temperature and, when and if medical progress makes it possible, to attempt to revive you and cure what killed you . The current cost is somewhat over two hundred thousand dollars, either cash or in a life insurance policy payable to Alcor. For a lower price you can have them freeze just your head, on the theory that medical technology good enough to bring a frozen body back to life will be good enough to grow you a new body and attach you to it. The design information for your body, after all, is in every cell.
The literature from Alcor that you are supposed to read before signing up contains a very lengthy list of reasons it might not work. The argument for doing it anyway, assuming you can manage the cost — less the earlier you sign up, given the nature of life insurance — is that the odds of being brought back to life if you are buried or cremated are even lower.
Uploading
My best guess at what I am is a computer program running on the hardware of my brain. If that is correct, it might at some point become possible to build a computer that can fully emulate my brain — and copy me to it.
That raises several interesting questions. After my brain has been destructively analyzed and the precise structure, not only what neuron connects to what how but what state every neuron is in, duplicated in hardware, have I just been moved from carbon to silicon or have I been killed and a computer program produced that thinks it is me? From the standpoint of other people, a publisher who wants me to write another book or a fan who wants to read it, it may not much matter, but it matters to me.
Many years ago I got into a discussion of the question with the late Marvin Minsky, a prominent artificial intelligence researcher. His response was to imagine that a very fast link is set up between your brain and the computer you are being uploaded to. As each neuron in your brain is destroyed the software emulating it takes its place. You start out doing 100% of your thinking in your brain, end up doing 100% of your thinking in the computer, having made the transition continuously — 99% brain/1% computer, 98/2, …
Intuitively, doing it that way, with me conscious through the whole process, feels like moving my consciousness from one host to another. Does that imply that the same is true of the discontinuous version?
What if my brain is copied without destroying it? There are now two versions of me, one in carbon, one in silicon. They may be, initially at least, identical, but they can’t both be me. Does that reverse the conclusion from Minsky’s hypothetical?
A computer program can be copied. Once I have been uploaded, so can I. One, two, many Davids. For a discussion of the implications see Chapter 19 of Future Imperfect.
I Might Turn out to Have an Immortal Soul
An earlier post discussed the puzzle of consciousness. As I put it then:
My picture of the world fits most things. I understand a car, a tree, a computer, not in the sense of being able to build or repair them but in the sense of seeing nothing about them inconsistent with a view of the world based on modern science. A p-zombie, something that appears to be an intelligent human being, something that could pass a Turing test but has no consciousness —GPT4 might qualify — fits my world view too. But nothing in that view explains what must be added to a p-zombie to convert it into me.
My belief that other people exist is a deduction from information reaching me — my consciousness — through my senses. My scientific world view is based not on my own observations but on things my senses report that other people report about their observations, plus elaborate deductions from that information, some of which I can do for myself, much of which I have to take on trust. My knowledge of my own existence, the fact that there is someone looking out through my eyes, is in contrast a first-hand observation continually renewed. Cogito ergo sum.
I do not understand the nature of consciousness. I do not know what I am. Software running on the hardware of my brain seems the most plausible answer but, since I do not understand how software can be conscious, how it can be me, it might be wrong.
The obvious, and very ancient, alternative is that consciousness is a different kind of thing than the physical reality that we more or less understand. If so, its existence might not depend on the existence of the physical structure of my brain. Certainly there is some connection — a blow on the head can cause unconsciousness, alcohol in the brain effects thinking, sleeping is simultaneously a characteristic of my brain and of my mind. All that is evidence — but evidence short of proof.
The Odds
I do not know enough to calculate the odds that one of the four might work, that I will still be around in some form more than fifty years from now. I can, however, report my guesses.
The ability to stop or reverse aging seems like something almost certain to happen, short of social collapse sufficiently bad to stop progress in the relevant fields. There is, as I argued above, no reason to think it is impossible. It is something that many people, in particular many old people, very much want, and old people have a great deal of power, political and economic. What must be produced to do it is knowledge which, once produced, is easily reproduced; if the problem is solved by someone, somewhere, the solution is almost certain to spread.
There remains the question of how fast it will happen. People have been looking for ways to slow aging, so far with limited success. Part of the problem is that testing a solution on a person takes a very long time. Testing on rats is much faster, but we don’t know how well anything we learn from rats will apply to us. Perhaps I am being too conservative, but I give only a ten percent chance that the problem will be solved soon enough to be of use to me.
Cryonic suspension is here already. The problem is that getting suspended and revived requires me to win a sequence of gambles. I have to die under circumstances sufficiently controlled, most obviously slowly in a hospital, so that my body can be frozen before too much damage has been done. Alcor has to continue to function well enough so that the money I have paid them gets used to preserve my body and eventually revive it, not stolen or diverted to other purposes — it’s not as if I will be there to guard it. The society has to continue to function well enough for medical progress to continue and past commitments to hold. It has to be possible to revive a frozen body. People have to learn how to do it. Enough of me has to remain in my frozen body so that bringing it back to life brings me back to life. Each of those strikes me as reasonably likely, but not the combination of all of them.
Ten percent.
Uploading may eventually become possible, but not soon, so the only way I will be able to take advantage of it is if one of the first two keeps me alive. I have already included them in my calculation, so uploading adds nothing to the total probability.
What about the possibility that I am wrong, some religion right, about the nature of consciousness? The modern scientific world view, which I generally share, rejects it. But quite a lot of the people who have ever lived, including quite a lot now living, many of them educated people in modern developed societies, accept it. I see no convincing proof of either side of the argument but find it hard to give a picture of the world that I don’t believe in odds of more than ten percent.
Add it all up and my subjective probability, as of writing this, for my existence in some form at a date more than fifty years in the future is thirty percent. Not very good odds, but higher than they were before I went through this exercise.
It’s a gamble I might win.
I’m with Woody Allen on this one. I’m not afraid of dying. I just don’t want to be there when it happens.
Good joke, but also kind of true. I’m not afraid of being dead but the actual process of going through that door seems like it could be unpleasant.
There's some small amount of writing about limited lifespans and evolution, particularly about differences in lifespans between species. I don't know how much is reasonably based on research (probably modeling or similar) and how much is "just so" stories.
What I gather from this is that:
- if the death rate from causes other than aging is high, evolution favours "live fast, spawn copiously, and die young". There's no point evolving longevity if odds are you'll die young of predation, accident, disease, etc. etc.
- if the non-aging death rate is lower, evolution moves towards a longer lifespan, and often a later start to producing offspring. Maybe fewer offspring too, each with more parental investment. You can see this with (some) pairs of closely related species in environments with large differences in non-aging mortality.
- if an older individual has big reproductive advantages, such that spawning early nets you a small clutch, with each year's potential clutch increasing, you get the big mama fish phenomenon, and negligible aging - each year the fish survives, it's bigger, and can produce more offspring than the year before. Evolution strongly favours individuals of such a species not aging.
- as far as I know, 2 species have evolved menopause - females stop producing new offspring long before aging would be likely to kill them. I'm not satisfied that we fully understand this, except for the obvious - already-produced offspring must do better under this system, such that the menopausal female has more (great)grandchildren on average than a non-menopausal but otherwise similar female. Humans are one of these species, so this probably matters to understanding human aging.
One other point: humans have an enviably low non-aging death rate, at least in "advanced" countries. This ought to be creating evolutionary pressures towards longer breeding lifetimes. Except of course that most of us stop breeding well before out bodies can't do it, either for reasons of investment in existing children or simply because evolution hasn't made us into instinct-driven breeding robots - we have goals separate from yet more babies. (Some of us even work hard to force competitors to have babies they don't want!)