Stephen Gordon has a review of a new book on the prospects for indefinite lifespan.

The virtual elimination of death by old age in society will demand that we be a spacefairing civilization. We have to expand beyond this Earth and the time for doing this is running out.

Even the most optimistic medical technology improvements in the coming century are not going to get us anywhere near immortality.

Consider the following amazing advances:

(1) Perfection of artificial hearts. Suppose this reduces the deaths from heart disease (29% of all deaths) by 90%. (It can't reduce heart disease by 100%, i.e. eliminate them, because it will introduce new deaths associated with accidental failure of the new curative technology. That is, people may no longer die of heart disease per se, but they will start dying from accidental mechanical failure of their artificial hearts.)

Elimination of 90% of all deaths from heart disease would increase average lifespan from 77 years to 104 years.

(2) Gene therapy, rational drug design, or nanobots that can cure any cancer, of any kind and no matter how advanced on diagnosis. Assume this would reduce cancer deaths (23% of all deaths) by, again, 90%. (Not 100% because, again, the nanobots will on rare occasion screw up and kill the patient.)

Elimination of 90% of all cancer deaths increases average lifespan to 97 years.

(3) Both of the above! Elimination of 90% of all heart disease deaths and 90% of all cancer deaths increases average lifespan from 77 years to 145 years.

An average lifespan of 145 years is nothing to sneeze at -- may God send it to my children -- but it's hard to imagine massive social changes coming from this increase in lifespan alone.

I think longevity will be the next big evolution of man. I truly think that we are stuck in a cycle of oppression, violence, and class struggle that will only resolve itself through increased longevity. As people grow older, understand more, and by and large become wiser then we will really start to see that we are the ones that make things so much more harder for ourselves then they really need to be. Eventually our understanding will reach a point that there is so much more going on in this universe other then our pointless squabbles on this ball of rock. Problem is that our life span is so short that it often takes several generations until maybe, hopefully, possibly we begin to see how to learn from a mistake.

I had this question asked of me in an English class one time, and of course the subsequent 1 page opinion peice was assigned. I'd love to live for a 1000 years as long as I could maintain a 30 something physique. I think if we really did have a messiah or chosen one and he hung around for several thousand years, then we'd not have nearly half the problems. I guess thats one reason why I don't buy the whole Jesus's story as its told. Cause if a benevolent God really cared about us he'd left his son here for eternity instead of taking him away after a measely 30 years or so (which was a lifetime at one point).

Carl wrote:
"An average lifespan of 145 years is nothing to sneeze at -- may God send it to my children -- but it's hard to imagine massive social changes coming from this increase in lifespan alone."

I can think of a few 'massive social changes' that would come from nearly doubling the average life span.

1) How will social security pay for 80 years of retirement? Or will people be forced to work until their 120? What politician will have the guts to *double* the retirement age?

2) You've just effectively doubled the number of people in this country. Where will they live? What will they eat? What roads will they drive on? Where will we get the gasoline for their cars? Our infrastructure is set up for 300 million people, with some extra capacity to slowly increase the population. Can it handle this radical change?

Like you, I hope this happens. I'd love to enjoy another 50 years with my parents, and my great-grandchildren. But surely there are serious implications.

-S

The elimination of disease would be something that improves the quality of life and aid in extending life, but what they're referring to in this book is something more fundamental, it's the genetic reset of cells' biological clock which would give the body the ability to regenerate indefinitely.

Regarding the "where will we all live" question...the world is hardly full up. Most of the US population lives in urban centers, while our midwest is actively *losing* population. As is Russia. The oceans have yet to be colonized. And there's always Antarctica (easier to get to and colonize than space).

Frankly, living space is likely to be the least of our problems.

Stephen Kohls:

(1) You're inconsistently imagining a world where you live longer without also imagining the new attitudes you'd develop in such a world. It's like thinking that, if you lived in the Middle Ages, you'd be appalled at how much people smell. No, you wouldn't, since it would be your daily reality. You wouldn't even notice it.

In the same way, if people routinely lived to be 140 and were healthy enough to work until 120, no one would feel that being "forced" to work until 120 was hideous. It would just be routine reality. They would think of retiring at age 65 in the same way that we now think of retiring at age 35 -- something unusual, lucky.

(2) You're perhaps confusing one-time effects with continuous growth. Population growth is only a big problem when it's never-ending, i.e. when it doubles and then doubles again and again forever, which is what happens when more people are born every year than die. A one-time doubling of the population over a generation is no big deal. American population has roughly doubled since 1955 -- I don't recall much in the way of painful adjustment.

B. Brewer:

Fair enough, but do recall that 10-15% of deaths are simply accidents or infection, which have nothing to do with any biological clocks. In which case, even with the elimination of every imaginable "internal" reason for death, i.e. complete biological perfection, you can't reasonably expect more than a 300-1000 year lifespan. Awfully long, but still well short of immortality.

Indeed, I would be surprised if human society with 300-1000 year lifespans differed in any very significant way from present society. Who among us seriously makes plans that take into account our finite lifespan until rather close to its end, e.g. until our 70s? We routinely act for most of our adult life as if death were so far off in the distant future that it need not greatly affect present planning. So what would change, really, if the "far off future" were 250 years away instead of 50?

I strongly suspect that most of our feelings about and concern with lifespan are driven by the simple fact that we die at all, and not really very much by how long or short a time we have. In which case, knowing you have 300 instead of 100 years, but knowing you're still going to die someday, that you will spend all but an eyeblink of eternity not existing, is not going to change us very much.

Carl Pham,

Here's a couple of things to consider. First, there's no use planning much for anything that happens more than say 50 years from now. It just isn't our problem. But if you were to live 250+ years, then suddenly it becomes your problem. I imagine also there would be people with successful 250 year plans, even if these people aren't the norm.

Second, most of the accidental causes of death are preventable, it's just not worthwhile if you die in 100 years. So that 300-1000 year lifespan is only valid if you continue to live in the same hazardous environment that we currently live in.

(1) No doubt. But this is just a moderate renormalization of long-range plan time scales. Unimpressive as a candidate for eye-opening social change. People change long-range plan time-scales all the time (e.g. in wartime they shorten up). Economists have a phrase for this: "long-term interest rates."

More to the point, I'm saying only a small fraction of our plans are truly long-range anyway, so any renormalization will have minor social consequences.

I think most of our planning is sufficiently short-range that we do not need (or even want) to factor in how long we are likely to live.

(2) Of course accidental death is preventable. We live in a deterministic universe, do we not? If I suspect I'm going to have a car accident today I can avoid it by, for example, not driving anywhere. But of course, it's the day I don't suspect I'll have an accident that I do. The point being that the problem is not so much preventing accident as it is foreseeing it.

Alas, the key fact about accidental death is that it's. . .well. . .accidental, intrinsically difficult to foresee, not what your best insight into the future predicts.

But I think your point is that as a society we can in principal take more general steps (seat belts, immunizations) to reduce conceivable if not foreseeable accidents. You suggest we do so less in the present because we have less lifetime to protect.

Nonsense. You've got the economics backwards: it's what's in short supply that commands the highest price. If people valued their lives according to how many years they've got left we'd grow more careless and adventuresome as we grew older instead of less. Instead, we find that the moments of our lives become more precious when it seems they are running out, just as one's very last dollar is more precious than one of a few thousand brothers resting in the bank.

From this point of view one might almost expect accidental death rates in a 300-year life-expectancy society to rise, dampening somewhat the advantages of eliminating non-accidental death rates.

But I don't think so. I think we value our lives at essentially constant value. We just value the state of being alive, like we value the state of being pain-free or in love. Going a long time without pain doesn't make you more ready to experience pain. Experiencing life is not like eating ice cream, where the more we already have the more satisfied we are, the less hungry we are for more, and the more easily we can contemplate having it taken away for good.

I guess thats one reason why I don't buy the whole Jesus's story as its told. Cause if a benevolent God really cared about us he'd left his son here for eternity instead of taking him away after a measely 30 years or so (which was a lifetime at one point).

Not to get into a long thread about theism v. atheism, but it always amazes me the number of people who choose not to believe in God because 'He didn't do things the way I would done it.' Tell you what, you create your own universe and you can run however you want.

People who bring up the issue of over-population still don't get it about immortality. A cure for aging means you get to live like your 25 years old, forever. Most 25 year olds that I knew had no desire to have kids at that time (later, maybe when I'm 35 or so). I really think that once we get immortality, that the birth rate is going to plummet through the floor. I have been saying this since the late 80's, when I was 25, and have yet to hear a decent counter argument.

Immortality will eliminate the need for social security and medicare. These programs were designed to take of old people because they grow old. Once aging is no longer a part of society, these programs can be eliminated.

Social security and medicare have problems already that need to be addressed, regardless of immortality. Immortality simply eliminates the basis for these programs.

I honestly do not understand why people use the existance of these programs as an argument against immortality.