Will we have to artificially limit lifespans in the future?

Suppose someday all disease and even aging is conquered by medical science.

Is it better to have a society that limits births to the rare occasions when people killed by accidents, or to artificially limit lifespans of all to continue to have a moderate birth rate?

For evolution to continue, I think lifespans would have to be ended artificially, a la “Logan’s Run”, although at a much later age (400? 500?) Also, peoples urges to reproduce would be satisfied.

Or is is better to have a society with people who live thousands of years, where children are very rare? For the sake of agument, assume people never get dementia, etc, and will stay healthy and alert “forever”.

This is assuming that other problems that we face won’t also be advanced. Why do we need limitations on human lifespans if we have a whole universe to explore, for example? Right now, we can’t live on the moon, but how come that won’t change? The same thing goes for the food we need. Maybe in the future, we won’t need more food than the planet can provide because all nourishment is in a pill. There are a ton of things which would make more people less of a problem, and I see no reason why those developments would be stunted while science is prolonging lives.

Not necessarily. A complete cure for aging would certainly involve a certain amount of genetic manipulation. If we could do that, I’m sure we could evolve ourselves as much as we needed, and at a much quicker pace than normal Darwinian evolution (which, according to some, doesn’t even occur in our species anymore, BTW).

We can’t even force people to control popping rug rats out by the ton and when one program started inserting the injectable birth control strips into the arms of Native American Indian women on welfare as a prerequisite to staying on the program, all hell broke loose.

You can’t blame the monorities for it seems everyone in a lower economic class with limited education tend to breed like rabbits. Then, there are some who want huge families, like Marie Osmond. She’s working on her 6th or 8th kid now.

If we can’t control births, can’t even control national hunger – though we pay farmers NOT to grow crops to keep prices high, can’t control the costs of life saving medication, and certainly can’t do more than irritate the massive illegal drug trade – what makes you think we’ll be able to start killing old folks at a certain age?

Probably, we’ll have a few wars to eliminate surplus population, but that always produces a baby boom afterwards so the benefits don’t last long. Kill off a couple of hundred thousand and the survivors go into an almost instinctive mating rush.

We need to get out into space to colonize. Others have said we have plenty of empty land yet but that land is either inhospitable or providing us with little things like oxygen, weather, water and CO2 absorption.

Each time we try to control the population, usually only the 20% of the highly upper educated of the population cut down, while the lower 40% with average or lower IQ pump out kids like popcorn. Then the religious groups get involved and raise hell with legalized abortions. So, the smart ones, whose genes we need, stop reproducing much while the idiots breed like rats.

The reverse would happen if we started killing off elders. The poor minorities would be the heaviest hit. The rich would survive. Look at the 75 year old fossils on the Supreme Court now and the tottering religious leaders. How old was the last Pope before he was replaced? What about the Ayatollah’s in Iran? Bearded old fanatics, half senile. They’d survive. Old Black Joe wouldn’t. Neither would old White Clyde, living on Social Security and Disability in a leaky trailer. The elder Native Americans and Hispanics would be hit hard. Homosexuals? They’d have a whole new thing to worry about killing them off besides AIDS and homophobia.

I’d be willing to guess that none of our senior congressmen, who are all for term limits but never quite get around to voting them in, would survive until they croaked in office, vetoing a beneficial bill.

I think people will find ways to kill themselves off.

I would guess that by the time humans are living to be 500 years old, most of the planets will be teraformed and we’ll be living all over the friggin place. So I don’t think there’ll be a problem. But the Earth will look like that one City-Planet in Episode I. I bet the future subway will be kick ass!

First of all, the chances that we will somehow be able to eliminate all diseases is just ridiculous. How can you possibly control species that breed that fast? As it is, antibiotics are often rendered useless by overuse. There will always be a few li’l fuckers that are immune to whatever we happen to throw at them.

Says who? Show me some solid stats that show minorities and/or lower income people have a significantly larger number of children as opposed to white and/or rich Americans. I don’t mean four kids as opposed to one kid, either. At any rate, it’s not so much the number of kids you have as how much you spend on them. Rich people, particularly rich Americans, no matter how many kids they have, consume a larger amount of resources than any other race or nationality worldwide.

Back to the main topic: if you’re going to limit aging, you’d better make the cutoff point a helluva lot sooner than 400 years. Of course, there’s also the question of “quality of life” and whether anyone would want to live that long. Vampires and immortals are nice to watch on television, but past age 70 life for most people starts to get miserable, and it’s not just because of the physical condition of being old.

The OP appears to me to contain some errors of concept.

It’s always possible lives will be greatly prolonged by the abolition of aging and disease. ISTR a factoid that if all “natural” deaths were eliminated, leaving only accident, murder, and suicide as causes of death, and if the rates of these were to remain unchanged, people would have a half-life of about 2,000 years.

Of course, it’s that second assumption that is highly questionable. Having done it all, or at least as much as one’s physical, mental, financial, etc., resources allow, will the average person wish to repeat it again for Round 2? Many have, indeed, opined that most people will kill themselves, either outright or through sheer carelessness, well before the half-millennium mark is reached.

The “birth rate” is, of course, a birth rate by time. Whilst we may assume for the sake of argument that women will remain fertile throughout their long lives, the birth rate now is slightly more than 2 children/woman (i.e., pretty damn close to replacement rate), and well below what could be achieved in the absence of birth control (although it may come as a shock to some of the Teeming Thousands, women do not, as a rule like being barefoot and pregnant). Contra SpyderA48’s assertions, there is no evidence whatever that there is a philoprogenitive instinct in humans. Having a child may become a prestige item in the future, as having a Porsche is now, but even in our current society, there is no sign of that happening.

As for evolution, it is clear that physical evolution has been outclassed by technological for some tens of thousands of years now (anyone who disagrees should write the words “habitat destruction”). Given the biological breakthrough necessary to make the assumption of the OP reality, it is as RoboDude says; physical evolution would be highly inferior and of questionable necessity.

I doubt it.

As lifespans increase, people will just become more accomplished and find new things to do which could never be accomplished in 70 years. In particular, there are lots of projects (space-related, etc.) which few people support because they figure they’ll be dead long before the rewards come in.

I know that if I could have 1000 years, there are plenty of things I’d like to learn. The bigger question is – how will our memories hold up? Will we really be able to remember more than 50 years at a time? Will we be able to get secondary storage to preserve experiences forever?

I think most people would get tired of life eventually and end their own lives. Plenty of people get impatient to die now, when we only have to wait a few decades. I almost killed myself because of boredom when I was in my early 20s. If I have a few thousand more, I bet it will happen again, though I will do a better job next time.

We tend to assume that immortality is a long way off, but it might be closer than we think. The reason for aging is that over time, our DNA breaks down. If we could find a way to prevent disintegration of DNA, or to replace broken DNA with new strands, than old age would become a thing of the past from the physical perspective. There is no mechanism for doing such things right now, but at least we understand the chemcial structure of DNA and the proteins that act on it, so we might be closer than you think.

IMO, I don’t think artificially enhanced lifespans will become an issue, because I don’t think humankind will make it out of its adolescence alive. I think we will have managed to off ourselves long before we figure out how to eliminate the processes that cause aging and death. A species as prone to soiling its nest as badly as humans do is not in it for the long haul, to my way of thinking.

I read somewhere that scientists have extrapolated the maximum human life-span to be around 120 years…its not possible to extend that span farther becaude metabolizm has worn out the genes.
I suppose if we had medical science advance to the point where all disease is curable, and all injury is repairable, we would have to up the retirement age to 85 years

Wrong enolancooper. Or, at least in need of explanation. 120 years is about the maximum life span of a human if no genetic manipulation is done. But why would we limit ourselves to that? Every cell on earth is about 3.8 billion years old. The only reason that humans die is because it is programmed into the genome. There is nothing special about sequoia cells that allow them to live for milennia; just different genes. Bacteria basically live for billions of years. The differences are in our modes of reproduction. Bacterial genomes must remain in pristine condition so that it can replicate and divide. Human genomes, however, merely have to remain intact for twenty or thirty years. After reproductive age, selection cannot work to shape the genome; reproductive success has already been established. I.e., things like heart disease and altzeimers can’t be selected for, because one has already passed one’s genes on before being affected by the ailments. Consequently, the human genome gets filled with junk that causes us to deteriorate after reproductive age. But this genetic junk could be culled with sufficiently sophisticated techniques.

Cells are capable of lasting forever, which is why we still have life 4 billion years after it developed.

And Revtim, I don’t see how ending the lives of innocent citizens could be anything short of murder. Why arbitrarily destroy a thousand years worth of knowledge, experience, and wisdom? Legislate birth rates, put birth control in the drinking water, expand to the stars, whatever. But don’t kill peole off for the hell of it; there’s got to be a better solution than that.

As regards the half-life of 2000 years thing, ISTR that actually death by accident would be virtually certain within 500 years.

pan

It wouldn’t be murder because it would be legal, right? Murder is a legal definition. In any case, I was imagining a society where people would be willing to die at this point, because it would be part of their culture and mores.

A lot of people mentioned the “expand to the stars” option, I have some questions about that. Has overpopulation in an area ever been solved by the opening of a frontier? Or has it only been slightly alleviated? I imagine that most frontiers really fill up from people being born there, not from immigration. I’m only speculating here, though. Any historical info people can offer on the subject would be most welcome.