Parfit argued that this argument led to the “Repugnant Conclusion,” the idea that the best sort of world is one with a large population with lives barely worth living.
So the Mere Addition Paradox doesn’t prove what Parfit thought it did? We don’t have any moral obligation to tile the universe with people whose lives are barely worth living?
As I understand it, Parfit’s Repugnant Conclusion was that, given any possible world (even one with billions of people who each have an extremely high quality of life), there is a better possible world in which everyone has a life that is barely worth living (better because the population is much larger, and “barely worth living” is better than nothing). The argument he made was that the Repugnant Conclusion followed from most theories of population ethics (that is, most attempts to define “better” in this context), but most people refused to accept it.
That does not mean that a high-population low-quality-of-life world is the best possible world; a possible world with the same high population and higher quality of life would be even better. And it does not necessarily mean that we should strive for a world with high population and low quality of life; which possible world we should strive for depends on which possible worlds are reachable from here. But it does mean accepting that a hypothetical possible World 1, where there are lots of people and everyone has a life that is barely worth living, is better than a hypothetical possible World 2, where there are fewer people (though perhaps still billions or more) and everyone has a high quality of life. Many people refuse to accept this conclusion and find it repugnant, even if it is implied by the moral theory that they endorse.
Exactly. The original post is straightforwardly wrong, and doesn’t even do its readers the courtesy of including a one-line summary that lets them avoid having to read the whole thing. The fact that it’s at +40 is a damning indictment of LessWrong’s ability to tell good arguments from bad.
The only serious mistake I see in the original post is that it misinterprets Parfit. I agree with Unnamed that it does. But LessWrongers haven’t necessarily read Parfit, and they may have seen his ideas misused to argue in the way the post criticizes, so they can’t really be expected to detect the misinterpretation.
As I understand it, Parfit’s Repugnant Conclusion was that, given any possible world (even one with billions of people who each have an extremely high quality of life), there is a better possible world in which everyone has a life that is barely worth living (better because the population is much larger, and “barely worth living” is better than nothing).
The Mere Addition Paradox was the main argument Parfit used to argue that a possible world with a larger population and a lower quality of life was necessarily better. My argument is that the MAP doesn’t show this at all. I am aware that it was not the only argument Parfit used, but it was the most effective, in my opinion, so I wanted to take it on.
The argument he made was that the Repugnant Conclusion followed from most theories of population ethics (that is, most attempts to define “better” in this context), but most people refused to accept it.
It helps that I am already using a somewhat abnormal theory of population ethics. Alice and Bob elucidate it to a limited extent, but it’s somewhat similar to the “variable value principle” described in Stanford’s page on the subject. Basically I argue that having high total and high average utility are both valuable and that it’s morally good to increase both. I use the somewhat clunkier phrases “use resources to create lives worth living” and “use resources to enhance the utility of existing people” to avoid things like Ng’s Sadistic Conclusion and Parfit’s Absurd Conclusion.
According to the theory I am using, possible World 1 is worse than hypothetical World 2, providing both worlds have access to the same level of resources. My solution to the Mere Addition Paradox seems to indicate that World 1 might be better than World 2 if it has access to many more resources to convert into utility. However, a world with a smaller population, higher average utility, and the same level of resources as World 1 would always be better (providing the higher average utility was obtained by spending resources enhancing existing people’s utility, not by killing depressed people or something like that).
The Mere Addition Paradox was the main argument Parfit used to argue that a possible world with a larger population and a lower quality of life was necessarily better.
What Parfit argued is that, given any possible world, there is a better world with a larger population and a lower quality of life (according to most people’s definitions of “better”). There is even a better world with a much larger population and a quality of life that is barely above zero. It sounds like you agree, but you’re just noting that the higher-population, lower-quality-of-life, better world also differs in other ways; in particular, it has more resources.
At least that’s how I read it when you say: “For every population, A, with a high average level of utility there exists another, better population, B, with more people, access to more resources and a lower average level of utility.” To me, that sounds like you are biting the bullet and accepting the Repugnant Conclusion. You just think that the conclusion isn’t so repugnant, because those worlds also differ in amount of resources.
Is the following a fair summary of your position?: When looking at the possible future worlds that are reachable from a given starting point, a barely-worth-living world will never be the best world to aim for, because there is always a better option which has higher quality of living (i.e., an option that makes better use of the resources available at the starting point).
What Parfit argued is that, given any possible world, there is a better world with a larger population and a lower quality of life (according to most people’s definitions of “better”). There is even a better world with a much larger population and a quality of life that is barely above zero. It sounds like you agree, but you’re just noting that the higher-population, lower-quality-of-life, better world also differs in other ways; in particular, it has more resources.
My understanding of Parfit is that he believed the Mere Addition Paradox showed that a world that differed in no other way besides having a larger population size and a lower quality of life was better than one with a smaller population and a higher quality of life. That’s why it’s called the Mere Addition Paradox, because you arrive at the Paradox by adding more people, redistributing resources, and doing nothing else. That is what I understand to be the Repugnant Conclusion. What makes it especially repugnant is that it implies that people in the here and now have a duty to overpopulate the world.
You seem to have understood the Repugnant Conclusion to be the belief that there is any possible society that has a larger population and lower quality of life than another society, but is also better than that society. To avoid quibbling over which of us has an accurate understanding of the topic I’ll just call my understanding of it RC1 and your understanding RC2.
I do not accept RC1. According to RC1 a world with a high population and low quality of life is better than a world that has the same amount of resources as the first world, a lower population, and a higher quality of life. I do not accept this. To me the second world is clearly better.
I might accept RC2. If I get your meaning RC2 means that there is always a better population that is larger and with lower quality of life, but it might have to be quite a bit larger and have access to many more resources in order to be better. For instance according to RC2 a planet of 10 billion people with lives barely worth living might not be better than a planet of 8 billion people with wonderful lives. However, a galaxy full of 10 trillion people with lives barely worth living and huge amounts of resources might be better then the planet of 8 billion people with wonderful lives.
Would you agree that I have effectively refuted RC1, even if you don’t think I refuted RC2?
To me, that sounds like you are biting the bullet and accepting the Repugnant Conclusion. You just think that the conclusion isn’t so repugnant, because those worlds also differ in amount of resources.
Again, I think I might accept what you think the RC means (RC2). However, I do not accept my understanding of the Repugnant Conclusion (RC1), which is that in two otherwise identical worlds the one with the lower quality of live and larger population is better.
I think the reason my post is so heavily upvoted is that a great many members of this community have the same understanding of what the Repugnant Conclusion means as I do.
Is the following a fair summary of your position?: When looking at the possible future worlds that are reachable from a given starting point, a barely-worth-living world will never be the best world to aim for, because there is always a better option which has higher quality of living
My understanding of Parfit is that he believed the Mere Addition Paradox showed that a world that differed in no other way besides having a larger population size and a lower quality of life was better than one with a smaller population and a higher quality of life.
No, the statement is that for any world with a sufficiently high quality of life, there is some world that differs in no other way besides having a larger population size and a lower quality of life which is better.
I don’t see how your phrasing is significantly different from mine. In any case, I completely disagree with that statement. I believe that for any world with a large population size and a very low quality of life there is some world that differs in no other way besides having a smaller population size and a higher quality of life which is better.
The reason I believe this is that I have a pluralist theory of population ethics that holds that a world that devotes some of its efforts to creating lives worth living and some of its efforts to improve lives that already exist is better than a world that only does the former, all other things being equal.
Note that your statement does not contradict the Mere Addition Paradox.
You’re right. It doesn’t contradict it 100%. A world a trillion people with lives barely worth living might still be better than a world with a thousand people with great lives. However, it could well be worse than a world with half a trillion people with great lives.
What my theory primarily deals with is finding the optimal, world, the world that converts resources into utility most efficiently. I believe that a world with a moderately sized population with a high standard of living is the best world, all other things being equal.
However, you are quite correct that the Mere Addition Paradox could still apply if all things are not equal. A world with vastly more resources than the first one that converts all of its resources into building a titanic population of lives barely worth living might be better if its population is huge enough, because it might produce a greater amount of value in total, even if is less optimal (that is, it converts resources into value less efficiently). However, a world with the same amount of resources as that has a somewhat smaller population and a higher standard of living would be both better and more optimal.
So I think that my statement does contradict the Mere Addition Paradox in ceteris parabis situations, even if it doesn’t in situation where all things aren’t equal. And I think that’s something.
No. Your statement does not contradict the Mere Addition Paradox, even in, as you say, “ceteris paribus situations”. This is really a matter of first-order logic.
Alright, I think I found where we disagree. I am basically going to just repeat some things I just said in a reply to Thrasymachus, but that’s because I think the sources of my disagreement with him are pretty much the same as the sources of my disagreement with you:
I interpreted the Repugnant Conclusion to mean that a world with a large population with lives barely worth living is the optimal world, given the various constraints placed on it. In other words, given a world with a set amount of resources, the optimal way to convert those resources to value is to create a huge population with lives barely worth living. I totally disagree with this.
You interpreted the Repugnant Conclusion to mean that a world with a huge population of lives barely worth living may be a better world, but not necessarily the optimal world. I may agree with this.
To use a metaphor imagine a 25 horsepower engine that works at 100% efficiency, generating 25 horsepower. Then imagine a 100 horsepower engine that works at 50% efficiency, generating 50 horsepower. The second engine is better at generating horsepower than the first one, but it is less optimal at generating horsepower, it does not generate it the best it possibly could.
So, if you accept my pluralist theory of value (that places value on both creating new people, and improving the lives of existing ones), we might also say that a population Z, consisting of a galaxy full of 3 quadrillion of people that uses there sources of the galaxy to give them lives barely worth living, would be better than A, a society consisting of planet full of ten billion people that uses the planet’s resources to give its inhabitants very excellent lives. However, Z would be less morally optimal than A because A uses all the resources of the planet to give people excellent lives, while Z squanders its resources creating more people. We could then say that Y, a galaxy full of 1 quadrillion people with very excellent lives is both better than Z and more optimal than Z. We could also say that Y is better than A, and equally optimal as A. However, Y might be worse (but more optimal) than a galaxy with a septillion people living lives barely worth living. Similarly, we might say that A is both more optimal than, and better than B, a planet of 15 billion people living lives barely worth living.
The arguments I have made in the OP have been directed at the idea that a population full of lives barely worth living is the optimal population, the population that converts the resources it has into value most efficiently (assuming you accept my pluralist moral theory’s definition of efficiency). You have been arguing that even if that population is the most efficient at generating value, there might be another population so much huger that it could generate more value, even if it is much less efficient at doing so. I do not see anything contradictory about those two statements. I think that I mistakenly thought you were arguing that such a society would also be more optimal.
And if that is all the Repugnant Conclusion is I fail to see what all the fuss is about. The reason it seemed so repugnant to me was that I thought it argued that a world full of people with lives barely worth living was the very best sort of world, and we should do everything we can to bring such a world about. However, you seem to imply that that isn’t what it means at all. If the Mere Addition Paradox and the Repugnant Conclusion do not imply that we have a moral imperative to bring a vastly populated world about then all it is is a weird thought experiment with no bearing on how people should behave. A curiosity, nothing more.
Even if your argument is a more accurate interpretation of Parfit, I think that idea that a world full of people barely worth living is the optimal one is still a common enough idea that it merits a counterargument. And I think the reason the OP is so heavily upvoted is that many people hold the same impression of Parfit that I did.
I’m pretty sure that this is not what Parfit was arguing.
As I understand it, Parfit’s Repugnant Conclusion was that, given any possible world (even one with billions of people who each have an extremely high quality of life), there is a better possible world in which everyone has a life that is barely worth living (better because the population is much larger, and “barely worth living” is better than nothing). The argument he made was that the Repugnant Conclusion followed from most theories of population ethics (that is, most attempts to define “better” in this context), but most people refused to accept it.
That does not mean that a high-population low-quality-of-life world is the best possible world; a possible world with the same high population and higher quality of life would be even better. And it does not necessarily mean that we should strive for a world with high population and low quality of life; which possible world we should strive for depends on which possible worlds are reachable from here. But it does mean accepting that a hypothetical possible World 1, where there are lots of people and everyone has a life that is barely worth living, is better than a hypothetical possible World 2, where there are fewer people (though perhaps still billions or more) and everyone has a high quality of life. Many people refuse to accept this conclusion and find it repugnant, even if it is implied by the moral theory that they endorse.
Exactly. The original post is straightforwardly wrong, and doesn’t even do its readers the courtesy of including a one-line summary that lets them avoid having to read the whole thing. The fact that it’s at +40 is a damning indictment of LessWrong’s ability to tell good arguments from bad.
The only serious mistake I see in the original post is that it misinterprets Parfit. I agree with Unnamed that it does. But LessWrongers haven’t necessarily read Parfit, and they may have seen his ideas misused to argue in the way the post criticizes, so they can’t really be expected to detect the misinterpretation.
The Mere Addition Paradox was the main argument Parfit used to argue that a possible world with a larger population and a lower quality of life was necessarily better. My argument is that the MAP doesn’t show this at all. I am aware that it was not the only argument Parfit used, but it was the most effective, in my opinion, so I wanted to take it on.
It helps that I am already using a somewhat abnormal theory of population ethics. Alice and Bob elucidate it to a limited extent, but it’s somewhat similar to the “variable value principle” described in Stanford’s page on the subject. Basically I argue that having high total and high average utility are both valuable and that it’s morally good to increase both. I use the somewhat clunkier phrases “use resources to create lives worth living” and “use resources to enhance the utility of existing people” to avoid things like Ng’s Sadistic Conclusion and Parfit’s Absurd Conclusion.
According to the theory I am using, possible World 1 is worse than hypothetical World 2, providing both worlds have access to the same level of resources. My solution to the Mere Addition Paradox seems to indicate that World 1 might be better than World 2 if it has access to many more resources to convert into utility. However, a world with a smaller population, higher average utility, and the same level of resources as World 1 would always be better (providing the higher average utility was obtained by spending resources enhancing existing people’s utility, not by killing depressed people or something like that).
What Parfit argued is that, given any possible world, there is a better world with a larger population and a lower quality of life (according to most people’s definitions of “better”). There is even a better world with a much larger population and a quality of life that is barely above zero. It sounds like you agree, but you’re just noting that the higher-population, lower-quality-of-life, better world also differs in other ways; in particular, it has more resources.
At least that’s how I read it when you say: “For every population, A, with a high average level of utility there exists another, better population, B, with more people, access to more resources and a lower average level of utility.” To me, that sounds like you are biting the bullet and accepting the Repugnant Conclusion. You just think that the conclusion isn’t so repugnant, because those worlds also differ in amount of resources.
Is the following a fair summary of your position?: When looking at the possible future worlds that are reachable from a given starting point, a barely-worth-living world will never be the best world to aim for, because there is always a better option which has higher quality of living (i.e., an option that makes better use of the resources available at the starting point).
My understanding of Parfit is that he believed the Mere Addition Paradox showed that a world that differed in no other way besides having a larger population size and a lower quality of life was better than one with a smaller population and a higher quality of life. That’s why it’s called the Mere Addition Paradox, because you arrive at the Paradox by adding more people, redistributing resources, and doing nothing else. That is what I understand to be the Repugnant Conclusion. What makes it especially repugnant is that it implies that people in the here and now have a duty to overpopulate the world.
You seem to have understood the Repugnant Conclusion to be the belief that there is any possible society that has a larger population and lower quality of life than another society, but is also better than that society. To avoid quibbling over which of us has an accurate understanding of the topic I’ll just call my understanding of it RC1 and your understanding RC2.
I do not accept RC1. According to RC1 a world with a high population and low quality of life is better than a world that has the same amount of resources as the first world, a lower population, and a higher quality of life. I do not accept this. To me the second world is clearly better.
I might accept RC2. If I get your meaning RC2 means that there is always a better population that is larger and with lower quality of life, but it might have to be quite a bit larger and have access to many more resources in order to be better. For instance according to RC2 a planet of 10 billion people with lives barely worth living might not be better than a planet of 8 billion people with wonderful lives. However, a galaxy full of 10 trillion people with lives barely worth living and huge amounts of resources might be better then the planet of 8 billion people with wonderful lives.
Would you agree that I have effectively refuted RC1, even if you don’t think I refuted RC2?
Again, I think I might accept what you think the RC means (RC2). However, I do not accept my understanding of the Repugnant Conclusion (RC1), which is that in two otherwise identical worlds the one with the lower quality of live and larger population is better.
I think the reason my post is so heavily upvoted is that a great many members of this community have the same understanding of what the Repugnant Conclusion means as I do.
Yes.
No, the statement is that for any world with a sufficiently high quality of life, there is some world that differs in no other way besides having a larger population size and a lower quality of life which is better.
I don’t see how your phrasing is significantly different from mine. In any case, I completely disagree with that statement. I believe that for any world with a large population size and a very low quality of life there is some world that differs in no other way besides having a smaller population size and a higher quality of life which is better.
The reason I believe this is that I have a pluralist theory of population ethics that holds that a world that devotes some of its efforts to creating lives worth living and some of its efforts to improve lives that already exist is better than a world that only does the former, all other things being equal.
Note that your statement does not contradict the Mere Addition Paradox.
You’re right. It doesn’t contradict it 100%. A world a trillion people with lives barely worth living might still be better than a world with a thousand people with great lives. However, it could well be worse than a world with half a trillion people with great lives.
What my theory primarily deals with is finding the optimal, world, the world that converts resources into utility most efficiently. I believe that a world with a moderately sized population with a high standard of living is the best world, all other things being equal.
However, you are quite correct that the Mere Addition Paradox could still apply if all things are not equal. A world with vastly more resources than the first one that converts all of its resources into building a titanic population of lives barely worth living might be better if its population is huge enough, because it might produce a greater amount of value in total, even if is less optimal (that is, it converts resources into value less efficiently). However, a world with the same amount of resources as that has a somewhat smaller population and a higher standard of living would be both better and more optimal.
So I think that my statement does contradict the Mere Addition Paradox in ceteris parabis situations, even if it doesn’t in situation where all things aren’t equal. And I think that’s something.
No. Your statement does not contradict the Mere Addition Paradox, even in, as you say, “ceteris paribus situations”. This is really a matter of first-order logic.
Alright, I think I found where we disagree. I am basically going to just repeat some things I just said in a reply to Thrasymachus, but that’s because I think the sources of my disagreement with him are pretty much the same as the sources of my disagreement with you:
I interpreted the Repugnant Conclusion to mean that a world with a large population with lives barely worth living is the optimal world, given the various constraints placed on it. In other words, given a world with a set amount of resources, the optimal way to convert those resources to value is to create a huge population with lives barely worth living. I totally disagree with this.
You interpreted the Repugnant Conclusion to mean that a world with a huge population of lives barely worth living may be a better world, but not necessarily the optimal world. I may agree with this.
To use a metaphor imagine a 25 horsepower engine that works at 100% efficiency, generating 25 horsepower. Then imagine a 100 horsepower engine that works at 50% efficiency, generating 50 horsepower. The second engine is better at generating horsepower than the first one, but it is less optimal at generating horsepower, it does not generate it the best it possibly could.
So, if you accept my pluralist theory of value (that places value on both creating new people, and improving the lives of existing ones), we might also say that a population Z, consisting of a galaxy full of 3 quadrillion of people that uses there sources of the galaxy to give them lives barely worth living, would be better than A, a society consisting of planet full of ten billion people that uses the planet’s resources to give its inhabitants very excellent lives. However, Z would be less morally optimal than A because A uses all the resources of the planet to give people excellent lives, while Z squanders its resources creating more people. We could then say that Y, a galaxy full of 1 quadrillion people with very excellent lives is both better than Z and more optimal than Z. We could also say that Y is better than A, and equally optimal as A. However, Y might be worse (but more optimal) than a galaxy with a septillion people living lives barely worth living. Similarly, we might say that A is both more optimal than, and better than B, a planet of 15 billion people living lives barely worth living.
The arguments I have made in the OP have been directed at the idea that a population full of lives barely worth living is the optimal population, the population that converts the resources it has into value most efficiently (assuming you accept my pluralist moral theory’s definition of efficiency). You have been arguing that even if that population is the most efficient at generating value, there might be another population so much huger that it could generate more value, even if it is much less efficient at doing so. I do not see anything contradictory about those two statements. I think that I mistakenly thought you were arguing that such a society would also be more optimal.
And if that is all the Repugnant Conclusion is I fail to see what all the fuss is about. The reason it seemed so repugnant to me was that I thought it argued that a world full of people with lives barely worth living was the very best sort of world, and we should do everything we can to bring such a world about. However, you seem to imply that that isn’t what it means at all. If the Mere Addition Paradox and the Repugnant Conclusion do not imply that we have a moral imperative to bring a vastly populated world about then all it is is a weird thought experiment with no bearing on how people should behave. A curiosity, nothing more.
Even if your argument is a more accurate interpretation of Parfit, I think that idea that a world full of people barely worth living is the optimal one is still a common enough idea that it merits a counterargument. And I think the reason the OP is so heavily upvoted is that many people hold the same impression of Parfit that I did.