What’s so special about living longer?

Atheist death panel: Red America's suspicions confirmed.

After reading about the death panel we held at Skepticon IV last week, a very clever philosopher friend of mine named Henry Shevlin wrote to me with a challenge to the transhumanist perspective. The transhumanist argument, which Eliezer made eloquently in the panel, is that death is a terrible thing that we should be striving to prevent for as long as possible.
Henry asks:

“Is death a tragedy because it involves a possible loss of utility, or because there’s some special harm in the annihilation of the individual? So consider two scenarios… Earth 1B and Earth 2B. Both of them have 100 million inhabitants at any one time. But Earth 1B has a very high life expectancy and a very low birth rate, while Earth 2B has a lower life expectancy and a very high birth rate. Otherwise, though, the two worlds are very similar. Which world is morally superior, by which I mean, generates more utils? “

Good question. Why, exactly, is prolonging existing lives better than creating new lives?

Let’s start with Henry’s Option 1 — that a person’s death is a tragedy because of the loss of the utility that person would have had, if he hadn’t died. Starting with this premise, can we justify our intuition that it’s better to sustain a pre-existing life than to create a new one?

One possible tack is to say that we can only compare utilities of possible outcomes for currently existing people — so the utility of adding a new, happy person to this world is undefined (and, being undefined, it can’t compensate for the utility lost from an existing person’s death). Sounds reasonable, perhaps. But that also implies that the utility of adding a new, miserable person to this world is undefined. That doesn’t sound right! I definitely want a moral theory which says that it’s bad to create beings whose lives are sheer agony.

You might also be tempted to argue that utility’s not fungible between people. In other words, my loss of utility from dying can’t be compensated for by the creation of new utility somewhere else in the world. But that renders utilitarianism completely useless! If utility’s not fungible, then you can’t say that it’s good for me to pay one penny to save you from a lifetime of torture.

Or you could just stray from utilitarianism in this case, and claim that the loss of a life is bad not just because of the loss of utility it causes. That’s Henry’s Option 2 — that death is a tragedy because there’s some special harm in the annihilation of the individual. You could then argue that the harm caused by the death of an existing person vastly outweighs the good caused by creating a new person. I’m uncomfortable with this idea, partly because there doesn’t seem to be any way to quantify the value of a life if you’re not willing to stick to the measuring system of utils. But I’m also uncomfortable with it because it seems to imply that it’s always bad to create new people, since, after all, the badness of their deaths is going to outweigh the good of their lives.

ETA: Of course, you could also argue that you care more about the utils experienced by your friends and family than about the utils that would be experienced by new people. That’s probably true, for most people, and understandably so. But it doesn’t resolve the question of why you should prefer that an unknown stranger’s life be prolonged than that a new life be created.

38 Responses to What’s so special about living longer?

  1. Bryan says:

    I’ve always thought of it in terms of cost to society. A child needs to be fed and trained (in school) for 20 years or so before they can become a productive and useful member of society. So a new person can be seen as society offering an upfront investment against their future productivity. Our investment pays off best, offers the most utility, when the person is productive for a very long time. Of course a person just living doesn’t help us, so the focus shouldn’t really be on increasing lifespan so much as useful lifespan. At some point our bodies and minds degenerate until our further utility to society is less than the expected utility from creating a new person. Based on a utilitarian system of morals, we should be focusing on making this point as close to expected lifespan as possible, rather than just trying to make the lifespan longer.

    • Henry Shevlin says:

      Nice suggestion! I think 20 years is over-egging it (in some parts of the world, even 5- and 6-year olds are net providers to a family, insofar as they consume few resources, and can play a useful role in things like childcare, chores, farming, or even manufacturing, etc.).

      More to the point, though, I think we can easily control for this in the relevant thought experiments. Let’s say that in World 2B (the mortal world), individuals have a child when they are 35 years old, and that child is a net dependent for 10 years. In World 1B (the immortal world), individuals have to regenerate every 35 years a la The Doctor, a process that is largely pleasant but renders them a dependent on society for 10 years (they can read and chat with friends, just not work: it’s sort of like shabbat). Then both scenarios involve the same number of dependent years. Now we can raise the question again: why should the rationalist prefer 1B to 2B?

      • Bryan says:

        According to the utility function I proposed there would be no reason to prefer one world to the other in that case. My intuition is ambivalent about it as well, I wouldn’t have a preference between 1B or 2B.

        To be honest I developed the utility function and reasoning for a different case, comparing the value of two lives. Basically answering the question, “Can one human life be intrinsically more or less valuable than another?” Comparing entire worlds where it yields the same value for each is a stretch but I thought it would be applicable to the discussion.

  2. Jacob Vohs says:

    Clearly many people would like the pleasant aspects of life (often utility) to persist longer than what is normal or typical. However it often seems that there is a feeling associated with anticipating death, even for the non religious, where not only will death bring an end to these events, but there will be regrets and feelings that persist after death about the end of our life events. Better to improve the quality of typical life spans IMO than to expend resources prolonging them at the expense of limited resources or simply to avoid regrets.

  3. Jesse Galef says:

    “Why, exactly, is prolonging existing lives better than creating new lives?”

    I wonder if we could make a case that each (ageless) life increases in utility over time as relationships get strengthened, knowledge is acquired, and perspective is gained. Replacing such a life with a newborn is to start from scratch and push the boulder back up the hill.

    Age and dementia mess with this model – though it might help justify being more devastated by the death of a 25 year-old than an 82 year-old.

    • Julia Galef says:

      I thought of that after writing the post, but it’s kind of an inelegant solution, don’t you think? Besides which I could come up with plenty of reasons why youth is higher-utility, such as the wonder and excitement of experiencing things for the first time.

      • Jesse Galef says:

        Ok, so it’s not a simple linear relationship of age to utility, there are tons of factors at play. You’re right. But my intuition still wants to say that some lives are better to live, and the cumulative effect of having more years to develop it seems very potent.

        I’m approaching it by asking what world has the most utility – how often would the optimal setup cycle through lives? The advantage between Earth 1B or Earth 2B is an empirical question dependent on the experience of living at different ages.

        From experience, we would probably agree that there’s more utility in being a curious and excited youth than, say, an angsty middle school student. The optimal life-replacement rate would take that into account, as well as the much higher utility which can be experienced after surviving through the rough waters of puberty.

        (A cure for Alzheimer’s and dementia would definitely change the optimal point for life expectancy. So would a societal shift toward abandoning its elderly to solitude in nursing homes.)

        My sense after only 25 years is that there are advantages to different ages, but they’re not equal. My life seems to be increasing in value, and I expect it to continue doing so for another couple decades at least, though I could be wrong about the experience of aging.

        The difference between two distributions of 100 Million lives can be meaningfully discussed, but the “calculation” depends on the details we haven’t brought up.

      • Jeffrey Soreff says:

        Aging makes the thought experiment unfortunately ambiguous.
        One can’t assume that aging is held constant at its current rate and also assume
        that a high-longevity world exists. In the industrial world, most people are killed by
        the effects of aging as things stand now, so it is internally inconsistent to hold it
        constant and also posit high longevity.

        Three very different interpretations of high longevity could be:

        a) Best case – stretch out the prime years – everyone gets say 950 extra years at the
        same quality of life as a young adult has now.

        b) Middling case – keep the same proportions of childhood/young adult/middle age/aged
        but stretch them all out

        c) Worst case – stretch out the last year (last heartbeat?) of current lifespan to add the
        950 extra years or so. (I’ll wager that almost no one wants to add 950 years of Alzheimer’s…)

      • NascentDreaming says:

        “Jeffrey Soreff says: […] Worst case – stretch out the last year (last heartbeat?) of current lifespan to add the
        950 extra years or so. (I’ll wager that almost no one wants to add 950 years of Alzheimer’s…)” no ceritus paribus?

      • Jeffrey Soreff says:

        NascentDreaming wrote: ““Jeffrey Soreff says: […] Worst case – stretch out the last year (last heartbeat?) of current lifespan to add the
        950 extra years or so. (I’ll wager that almost no one wants to add 950 years of Alzheimer’s…)” no ceritus paribus?”

        I’m sorry, I’m not quite following you. Could you elaborate a bit on what you said?

    • Henry Shevlin says:

      A couple of thoughts on this. First, I think it doesn’t explain the 25/82 year old issue – if anything, if the projected 5-year utility of an 82 year old was greater than that of the 25 year old, then we should mourn the 82 year old more.

      It seems to me that the utility cuts the other way: other things being equal, utility will decrease in the long run. Our world, alas, is one of diminishing returns. Falling in love for the twenty-second time isn’t as good as the first time over. The same is true of many other aspects of human life – seeing new places, buying your first home, reading the Tractatus for the first time, &c.. I think THIS is part of the reason why we mourn the loss of a twenty-something more than the loss of a octogenarian, precisely because they haven’t had the chance to have many very ‘one off’ high utility experiences which the octogenarian has.

      • Jesse Galef says:

        Agreed on the important points – I wasn’t clear when I typed my comment. I meant to say that the fact of aging reduces the value of a life over time. (The “it” in the second paragraph my comment was trying to refer to aging, not the model.)

      • Henry Shevlin says:

        You know, despite what I said about youth being a happier period than senescence (even leaving aging effects aside), my considered view is that the majority of people maintain a pretty fixed level of long term happiness throughout their lives and despite adversity, thanks to the ‘hedonic treadmill’ (http://en.wikipedia.org/wiki/Hedonic_treadmill). That’s why paraplegics and lottery winners are about as happy as everyone else, in the long-term. Hence the argument that certain phases of life are happier than others (probably) doesn’t get off the ground.

        It *is* true that there seems to be a small but measurable positive effect on happiness from the age of 50 onwards (http://en.wikipedia.org/wiki/Positive_psychology#Age). But here the data get messy: older people report the same or lower levels of moment-to-moment satisfaction in pager studies as younger people, but give higher judgements of overall life satisfaction when asked to complete surveys. This is a rather odd result (though you find the same thing when people have kids). My own (far from expert) view is that old people are better than young people at appreciating their own good fortune in reflective contexts, rather than actually experiencing more pleasure on a daily basis.

      • Jeffrey Soreff says:

        Diminishing returns applies across lives, as well to to events within a single life.
        Adding the seven billionth and first baby to a world has a much smaller return
        to everyone else in the world than the millionth baby had. No one is going to
        discover special relativity for the first time again.

    • Giles says:

      “a newborn is to start from scratch and push the boulder back up the hill”

      Is it? While a new life may have to learn from some things from scratch through experience(i.e. hot and cold), whereas, knowledge is passed from generation to generation and that knowledge is then developed upon. Arguably the utility of life will never die, just the utility of the individual. A different prespective and fresh energy comes with each new generation, a sustained generation with the one prespective and decreasing energy would limit the development of knowledge.

      But, I fear that I am limiting utility to knowledge.

      • Chris W. says:

        I think of it in terms of an experiment that a researcher is performing–let’s say the researcher sticks around for 5 years, does a decent bit of research, but does not complete the project. When it is time for him or her to depart, they hire another researcher. The outgoing researcher explains as much as possible to the new researcher, but they still will not be at the same point as the first researcher in terms of how familiar they are with the subject. While society does move forward due to passing down this knowledge, I suspect it would move faster if it were just the same people hanging out (given that these people are rational, thoughtful, reasonable individuals, and not stuck in their ways) rather than a constant influx of new individuals to be trained in the way of life. Especially since individuals tend to seize on certain issues in their youth and then will not let go of them even as they age–so while a certain generation may have clung to issues surrounding race and ethnicity because it defined their early lives, the generations that are young today don’t really bother much with those subjects and are instead focused on other topics more pertinent to their environment today.

        Got a little sidetracked there, but the point is, overall I feel there is more knowledge to be maintained and gained through keeping individuals around rather than having new individuals learning from them…controlling for those individuals’ traits, of course, as well as assuming that medical advances prevent mental/physical deterioration.

  4. Xan says:

    Julia, I think the solution to this dilemma is that my life generates more utility (per year) if I don’t have to worry about dying. It’s not that an unborn person is less important than me per se, but the fact of not existing doesn’t have any effect on their ongoing utility of zero, whereas the fact of continuing to exist has a positive effect on my utility. People who are alive strongly prefer not to die, i.e. the prospect of dying strongly impacts their utility!

    In principle this could be outweighed if our personal utility functions are sufficiently concave: if the first 50 years of life are way more awesome than the second 50 years, it could make sense to split that 100 years across 2 people. This is exactly the kind of question you will have to address for a utilitarian defense of transhumanism. (Personally I don’t think two 50-year lives are better, but that’s all I’ll say for now).

    • Henry Shevlin says:

      Xan, I agree with you that worry about death is one of the major downsides to living in a mortal world. However, worrying about death is not an intrinsic feature of death – it’s a feature of the way we think about it. If worrying about death is the really big downside to mortality, then our big concern should be efforts in psychology and neuroscience which would allow people to overcome their fear of death.

      (One downside to this – you might expect people to engage in more reckless behavior and would be less likely to intervene to stop smoking etc.. But if we’re envisaging a sufficiently sophisticated method of intervention, we could ensure that people feel obliged to try hard not to die, without actually fretting about it).

      • Xan says:


        Yes, in addition to enabling outcomes that generate as many utils as possible given preferences, a utilitarian wants to modify preferences to get the most utility out of things as possible. There are potentially limits to both of these endeavors though, and we probably aren’t at a corner where it makes sense to focus on only preference modification.

        Also worth noting it could be difficult to significantly modify everyone’s preferences towards death. You would have to build into people some deep inconsistencies. I have preferences over what *happens* in the world tomorrow. Am I supposed to relinquish those preferences if I happen to learn I’m going to be dead tomorrow? To accomplish this, you would pretty much have to hardwire “apathy in the case of death” into my preferences…but that conflicts with a lot of my other goals, including pretty fundamental ones I wouldn’t easily part with.

      • Jeffrey Soreff says:

        What if we look at it in terms of the anticipated future utility for members of
        the populations of the two planets? The members of earth 1B look forward
        to, say, 1000 years of (presumably net positive) existence, while the members
        of earth 2B look forward to, say, only 100 years. Even if neither group is
        particularly fearful of their deaths, the longer-lived group is still better off.

        (Given some discount rate for future pleasures, this does nearly saturate
        for lifetimes much longer than the inverse of the rate – unless the inverse
        discount rate scales with lifespan. If it is just a constant, say 1% per year,
        extending lifespans from say 2000 years to say 3000 years is less than a
        part-per-million addition to their anticipated utilities)

  5. Andrew T says:

    Interesting post, but perhaps the best part was the caption. Ironically, another one of red America’s greatest fears is Red America.

  6. Doug Molitor says:

    What about the idea that the longer we live, the wiser and more mature we become? What is the utility of wisdom versus innocence, maturity vs immaturity? Would you rather live in a society whose median age was 40…or 20?

  7. Winslow says:

    It seems like have many short lives versus few long ones would have three disadvantages:
    One, experiencing some one else’s death is a source of disutility: relatives and friends of the deceased experience significant pain and sorrow.
    Two, preparations for death (mental and otherwise) represent a significant amount of time and effort. This is similar to the point others have made that every time a person dies, the one “replacing” them needs to be educated.
    Three, the shorter the life span, the less chance have to meet personal goals and have satisfying experiences. To me, there seems to be value in letting people have a more ‘complete’ life.
    I don’t know if these are mitigated by advantages to having a large number of short lives. I can’t think of any and few of the ones I’ve read here seem that significant.

    • Winslow says:

      Of course, I meant “I can’t think of any and few of the ones I’ve read here DON’T seem that significant.”

  8. NascentDreaming says:

    Earth 1b has the highest utils. Earth 1b and 2b are nearly identical except Earth 1b cumulative experiences are higher on average than Earth 2b. Earth 2b’s experiences are short and chopped up between the overlapping lives of individuals on a planet of high birth rates. Earth 1b capitalized on the handicap that only an individual his or herself can apprehend those past experiences and cognitive processes. This ability greatly improves the formation of new ideas and concepts because it cuts out the laborious process of finding and sharing ideas with someone else who has useful information. Also, while it is true that young people are full of wonder and amazement, generally when we are young we are also full of incredible prejudice and narrow mindeness. Children are bogged down with misconceptions which lower there overall utils. On top of that in Earth 1b the birth rate is lower. It does not say that the survival rate is low so one must infer that the lower birth rate is a function of Earth 1b’s biology and not environmental pressures. Therefore the beings on Earth 1b take greater care since each child is worth more to them than those children are worth on Earth 2b. The child will recieve more attention, time and care resulting in a higher quality childhood which in turn results in more utils. Finally the real questin asked was “whats so special about living longer?” I would think that the longer you live has no affect on the “specialness” of each new chunk of time. Each chunk is worth exactly what it was worth with the first chunk, but an individuals insight would have increased with each chunk of time (until the body forces change) and that insight would see a greater return on utils as time goes by.

  9. Max says:

    Primitive organisms and people tend to have have higher birth rates and lower life expectancy than more evolved organisms and civilizations.
    Earth 2B would probably be more primitive than Earth 1B.

  10. Max says:

    A birth rate of more than 2 children per couple would cause the population to increase as long as life expectancy stays constant, no matter what that constant is. For the population to stay stable with a high birth rate, the life expectancy would have to keep decreasing, probably due to Malthusian catastrophes.

    Why not just say that Earth 1B and 2B have the same birth rate but different life expectancy?

  11. Vesuvium says:

    The question here is very close to a question raised by Derek Parfit in the 4th part of Reasons and Persons. Parfit was mainly concerned with benefits. You can contribute utilities to the world by benefitting people, or by making sure that the people who come to exist live happier lives than other people who might otherwise have come to exist. In the latter case, you don’t benefit anyone. According to what Parfit calls ‘The No Difference View’, we should be indifferent between promoting utility in these ways. Parfit defends the ‘No Difference View’ by using the following example:

    The Medical Programmes. There are two rare conditions, J and K, which cannot be detected without special tests. If a pregnant woman has Condition J, this will cause the child she is carrying to have a certain handicap. A simple treatment would prevent this effect. If a woman has Condition K when she conceives a child, this will cause this child to have the same particular handicap. Condition K cannot be treated, but always disappears within two months. Suppose next that we have planned two medical programmes, but there are funds for only one; so one must be cancelled. In the first programme, millions of women would be tested during pregnancy. Those found to have Condition J would be treated. In the second programme, millions of women would be tested when they intend to try to become pregnant. Those found to have Condition K would be warned to postpone conception for at least two months, after which this incurable condition will have disappeared. Suppose finally that we can predict that these two programmes would achieve results in as many cases. If there is Pregnancy Testing, 1,000 children a year will be born normal rather than handicapped. If there is Preconception Testing, there will each year be born 1,000 normal children rather than a 1,000, different, handicapped children. (p. 367)

    If we choose to treat condition J, we benefit people, since the child who will be born come to have a better life than they would otherwise have had. If we treat condition K, we don’t benefit anyone: there is no one of whom it could be said that their life is better than it would otherwise have been if the treatment hadn’t been administered. No one is made better off by this treatment, because it determines who will exist, and not what their life will be like.

    This makes the no difference view seem very attractive, I think, but other cases count against it. Imagine that I am walking past a shallow pond and that a child is drowning in this pond. I can easily save the child, but I choose not to. Instead, I decide to conceive a child who will replace this child who has drowned. Suppose the replacement would exactly compensate for all of the good that is lost and all the harm done because this child drowned. Still, it seems to me that I should have chosen to save the child rather than conceive its replacement. This can only be explained if utilities that arise as a matter of benefit to someone have some special importance in ethics.

    • NascentDreaming says:

      In your last example you discuss the utility of saving a child versus creating a new one and that would affect the over all utility in the world. You conclude that saving the child is important because utility ties into ethics. I think that there is a more simple way to look at the problem. If you look at the overall utility and the potential utility you can see why it is impossible to replace the utility lost with the drowning child with the utility of creating a new one. In scenario A) where you let the child drown all the utility or energy is disperesed and cannot be regained. In scenario B) where you save the child you still have the option of creating a new child if you would like. Further more it undoubtedly takes more energy to create something you have already thrown away than it does to sustain what is already here. So I think it is not hard to see how Earth 1b has more overall utility because each childs potential utitlity is higher than those children in Earth 2b.

      • Henry Shevlin says:

        NascentDreaming: there must be more going in Vesuvium’s example than the factors you flag up (the fact that you can always have another child, and the fact that there is more waste involved in letting the child die), because even when we control for them, the intuition remains.

        So consider. It’s a post-apocalyptic scenario, and Adam, a 5 year old child, is dying from radiation sickness. You have one vial of medicine left that can save his life. Alternatively, you can use that vial of medicine to allow a couple to successfully conceive a new child. Now, we have a strict either/or scenario. Additionally, let’s presume that Adam will take quite a while to convalesce, during which time he’ll be dependent on other people. Make this time as long as required to ensure that neither option (saving/letting die) is more wasteful than the other.

        Now, the scenario controls for the two factors you suggest, but our moral response (we should save Adam, rather than creating a new life) persists intact, hence it can’t be the factors which you indicated that are driving our moral response.

      • Jeffrey Soreff says:

        I kind of hate to say it (since I like the way the intuition to preserve Adam
        comes out now), but…Could this be status quo bias?
        (That is, in regard to how the replacement of Adam affects the society at large –
        I’d expect Adam to have a rather strong preference for not being replaced!)

        (I regard status quo bias as being less unfortunate than most biases.
        It is a reasonable heuristic to expect that advocates of changes are
        likely to oversell them… In the current thought experiment, look at
        how many features are being carefully tweaked to make Adam’s replacement’s
        effect come out to be the same as that of saving Adam. If this were a real
        question, would one plausibly expect that the alternatives would match so

  12. Dave says:

    “Or you could just stray from utilitarianism in this case…”

    Yes please.

  13. Seth Goldin says:

    Just because utility isn’t fungible between individuals doesn’t render utilitarianism useless. Preference utilitarianism is somewhat of a foundation of neoclassical economics, where utility is modeled as ordinal, not as cardinal in the classical Benthamite act utilitarian formulation.

  14. Zak says:

    I like this thought experiment. Thanks Mr. Shevlin for proposing it, and thanks Ms. Galef for sharing it!

    I wanted to add a clarifying question to this, though: In this discussion of longer life expectancy, are we merely considering adding extra years on to the end of our lifespans or are we expanding each individual stage of brain development as well? Because there might be a loss in utility due to not learning to speak until age 3 instead of 2, but there’d also be a benefit in overall neuroplasticity lasting past age 20.

    For me, the question of improved utility doesn’t just include “How well do we create new ideas/skills” which was covered quite well above, but it also has to include “How well do we *remove* poorly suited ideas from the overall culture?” As older people die off, they reduce the amount of people who believed *last* century’s ideas to make room for new people who are adapting and acclimating to our current mental environment. But if those people continued to live longer and longer, would their outmoded ideas persist longer and longer too? If the last generation to grow up with “The Earth is the center of the solar system” lived twice as long, would it have taken twice as long for Galileo’s ideas to finally penetrate?

    I was trying to take the concept of “life on Earth as a whole” and boil it down to a microcosm of “workers in a factory” and apply the question of older experienced workers (who know more but are more likely to keep using the same old methods that may no longer serve as technology changes) versus the younger inexperienced workers who may know less but will be creating new solutions to apply to the current technological environment instead of continuing to use solutions to the *previous* environment. Which are more valuable? Or, what is the desired mix of each to create the best mix of adaptability versus reliability?

    (That’s where the question of neuroplasticity came in — are the older workers of Earth 1B more able to reject old ideas and adapt to changing situations than older workers here on Earth 2B, or are they the same? If the same, then I think there’s a net *loss* in utility from increased lifespans due to cultural biases and prejudices persisting longer than currently.)

    Sorry for the ramblyness — I’ve never gotten around to studying argument style, so I meander a fair bit. But thanks again for this fun thought experiment!

    • Zak says:

      In summary: is there a *positive* utility to death? We always look at the negative utility (because none of us wants to die, because we’re too close to our own situation), but there might be positive benefits to human culture and civilization by us dying off earlier.

  15. Kaleberg says:

    “But that renders utilitarianism completely useless!”

    Is there some problem with this?

  16. Grognor says:

    I am a strong immortalist (as described by Steven Kaas here http://www.acceleratingfuture.com/steven/?p=22) for many reasons, none of which I am fit to describe here.

    He discusses the issue further here: http://www.acceleratingfuture.com/steven/?p=157

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