Population Ethics Shouldn't Be About Maximizing Utility

by Ghatanathoah14 min read18th Mar 201346 comments


Personal Blog

let me suggest a moral axiom with apparently very strong intuitive support, no matter what your concept of morality: morality should exist. That is, there should exist creatures who know what is moral, and who act on that. So if your moral theory implies that in ordinary circumstances moral creatures should exterminate themselves, leaving only immoral creatures, or no creatures at all, well that seems a sufficient reductio to solidly reject your moral theory.

-Robin Hanson

I agree strongly with the above quote, and I think most other readers will as well. It is good for moral beings to exist and a world with beings who value morality is almost always better than one where they do not. I would like to restate this more precisely as the following axiom: A population in which moral beings exist and have net positive utility, and in which all other creatures in existence also have net positive utility, is always better than a population where moral beings do not exist.

While the axiom that morality should exist is extremely obvious to most people, there is one strangely popular ethical system that rejects it: total utilitarianism. In this essay I will argue that Total Utilitarianism leads to what I will call the Genocidal Conclusion, which is that there are many situations in which it would be fantastically good for moral creatures to either exterminate themselves, or greatly limit their utility and reproduction in favor of the utility and reproduction of immoral creatures. I will argue that the main reason consequentialist theories of population ethics produce such obviously absurd conclusions is that they continue to focus on maximizing utility1 in situations where it is possible to create new creatures. I will argue that pure utility maximization is only a valid ethical theory for "special case" scenarios where the population is static. I will propose an alternative theory for population ethics I call "ideal consequentialism" or "ideal utilitarianism" which avoids the Genocidal Conclusion and may also avoid the more famous Repugnant Conclusion.


I will begin my argument by pointing to a common problem in population ethics known as the Mere Addition Paradox (MAP) and the Repugnant Conclusion. Most Less Wrong readers will already be familiar with this problem, so I do not think I need to elaborate on it. You may also be familiar with a even stronger variation called the Benign Addition Paradox (BAP). This is essentially the same as the MAP, except that each time one adds more people one also gives a small amount of additional utility to the people who already existed. One then proceeds to redistribute utility between people as normal, eventually arriving at the huge population where everyone's lives are "barely worth living." The point of this is to argue that the Repugnant Conclusion can be arrived at from "mere addition" of new people that not only doesn't harm the preexisting-people, but also one that benefits them.

The next step of my argument involves three slightly tweaked versions of the Benign Addition Paradox. I have not changed the basic logic of the problem, I have just added one small clarifying detail. In the original MAP and BAP it was not specified what sort of values the added individuals in population A+ held. Presumably one was meant to assume that they were ordinary human beings. In the versions of the BAP I am about to present, however, I will specify that the extra individuals added in A+ are not moral creatures, that if they have values at all they are values indifferent to, or opposed to, morality and the other values that the human race holds dear.

1. The Benign Addition Paradox with Paperclip Maximizers.

Let us imagine, as usual, a population, A, which has a large group of human beings living lives of very high utility. Let us then add a new population consisting of paperclip maximizers, each of whom is living a life barely worth living. Presumably, for a paperclip maximizer, this would be a life where the paperclip maximizer's existence results in at least one more paperclip in the world than there would have been otherwise.

Now, one might object that if one creates a paperclip maximizer, and then allows it to create one paperclip, the utility of the other paperclip maximizers will increase above the "barely worth living" level, which would obviously make this thought experiment nonalagous with the original MAP and BAP. To prevent this we will assume that each paperclip maximizer that is created has a slightly different values on what the ideal size, color, and composition of the paperclip they are trying to produce is. So the Purple 2 centimeter Plastic Paperclip Maximizer gains no addition utility from when the Silver Iron 1 centimeter Paperclip Maximizer makes a paperclip.

So again, let us add these paperclip maximizers to population A, and in the process give one extra utilon of utility to each preexisting person in A. This is a good thing, right? After all, everyone in A benefited, and the paperclippers get to exist and make paperclips. So clearly A+, the new population, is better than A.

Now let's take the next step, the transition from population A+ to population B. Take some of the utility from the human beings and convert it into paperclips. This is a good thing, right?

So let us repeat these steps adding paperclip maximizers and utility, and then redistributing utility. Eventually we reach population Z, where there is a vast amount of paperclip maximizers, a vast amount of many different kinds of paperclips, and a small amount of human beings living lives barely worth living.

Obviously Z is better than A, right? We should not fear the creation of a paperclip maximizing AI, but welcome it! Forget about things like high challenge, love, interpersonal entanglement, complex fun, and so on! Those things just don't produce the kind of utility that paperclip maximization has the potential to do!

Or maybe there is something seriously wrong with the moral assumptions behind the Mere Addition and Benign Addition Paradoxes.

But you might argue that I am using an unrealistic example. Creatures like Paperclip Maximizers may be so far removed from normal human experience that we have trouble thinking about them properly. So let's replay the Benign Addition Paradox again, but with creatures we might actually expect to meet in real life, and we know we actually value.

2. The Benign Addition Paradox with Non-Sapient Animals

You know the drill by now. Take population A, add a new population to it, while very slightly increasing the utility of the original population. This time let's have it be some kind animal that is capable of feeling pleasure and pain, but is not capable of modeling possible alternative futures and choosing between them (in other words, it is not capable of having "values" or being "moral"). A lizard or a mouse, for example. Each one feels slightly more pleasure than pain in its lifetime, so it can be said to have a life barely worth living. Convert A+ to B. Take the utilons that the human beings are using to experience things like curiosity, beatitude, wisdom, beauty, harmony, morality, and so on, and convert it into pleasure for the animals.

We end up with population Z, with a vast amount of mice or lizards with lives just barely worth living, and a small amount of human beings with lives barely worth living. Terrific! Why do we bother creating humans at all! Let's just create tons of mice and inject them full of heroin! It's a much more efficient way to generate utility!

3. The Benign Addition Paradox with Sociopaths

What new population will we add to A this time? How about some other human beings, who all have anti-social personality disorder? True, they lack the key, crucial value of sympathy that defines so much of human behavior. But they don't seem to miss it. And their lives are barely worth living, so obviously A+ has greater utility than A. If given a chance the sociopaths will reduce the utility of other people to negative levels, but let's assume that that is somehow prevented in this case.

Eventually we get to Z, with a vast population of sociopaths and a small population of normal human beings, all living lives just barely worth living. That has more utility, right? True, the sociopaths place no value on things like friendship, love, compassion, empathy, and so on. And true, the sociopaths are immoral beings who do not care in the slightest about right and wrong. But what does that matter? Utility is being maximized, and surely that is what population ethics is all about!


Let's suppose an asteroid is approaching each of the four population Zs discussed before. It can only be deflected by so much. Your choice is, save the original population of humans from A, or save the vast new population. The choice is obvious. In 1, 2, and 3, each individual has the same level utility, so obviously we should choose which option saves a greater number of individuals.

Bam! The asteroid strikes. The end result in all four scenarios is a world in which all the moral creatures are destroyed. It is a world without the many complex values that human beings possess. Each world, for the most part, lack things like complex challenge, imagination, friendship, empathy, love, and the other complex values that human beings prize. But so what? The purpose of population ethics is to maximize utility, not silly, frivolous things like morality, or the other complex values of the human race. That means that any form of utility that is easier to produce than those values is obviously superior. It's easier to make pleasure and paperclips than it is to make eudaemonia, so that's the form of utility that ought to be maximized, right? And as for making sure moral beings exist, well that's just ridiculous. The valuable processing power they're using to care about morality could be being used to make more paperclips or more mice injected with heroin! Obviously it would be better if they died off, right?

I'm going to go out on a limb and say "Wrong."

Is this realistic?

Now, to fair, in the Overcoming Bias page I quoted, Robin Hanson also says:

I’m not saying I can’t imagine any possible circumstances where moral creatures shouldn’t die off, but I am saying that those are not ordinary circumstances.

Maybe the scenarios I am proposing are just too extraordinary. But I don't think this is the case. I imagine that the circumstances Robin had in mind were probably something like "either all moral creatures die off, or all moral creatures are tortured 24/7 for all eternity."

Any purely utility-maximizing theory of population ethics that counts both the complex values of human beings, and the pleasure of animals, as "utility" should inevitably draw the conclusion that human beings ought to limit their reproduction to the bare minimum necessary to maintain the infrastructure to sustain a vastly huge population of non-human animals (preferably animals dosed with some sort of pleasure-causing drug). And if some way is found to maintain that infrastructure automatically, without the need for human beings, then the logical conclusion is that human beings are a waste of resources (as are chimps, gorillas, dolphins, and any other animal that is even remotely capable of having values or morality). Furthermore, even if the human race cannot practically be replaced with automated infrastructure, this should be an end result that the adherents of this theory should be yearning for.2 There should be much wailing and gnashing of teeth among moral philosophers that exterminating the human race is impractical, and much hope that someday in the future it will not be.

I call this the "Genocidal Conclusion" or "GC." On the macro level the GC manifests as the idea that the human race ought to be exterminated and replaced with creatures whose preferences are easier to satisfy. On the micro level it manifests as the idea that it is perfectly acceptable to kill someone who is destined to live a perfectly good and worthwhile life and replace them with another person who would have a slightly higher level of utility.

Population Ethics isn't About Maximizing Utility

I am going to make a rather radical proposal. I am going to argue that the consequentialist's favorite maxim, "maximize utility," only applies to scenarios where creating new people or creatures is off the table. I think we need an entirely different ethical framework to describe what ought to be done when it is possible to create new people. I am not by any means saying that "which option would result in more utility" is never a morally relevant consideration when deciding to create a new person, but I definitely think it is not the only one.3

So what do I propose as a replacement to utility maximization? I would argue in favor of a system that promotes a wide range of ideals. Doing some research, I discovered that G. E. Moore had in fact proposed a form of "ideal utilitarianism" in the early 20th century.4 However, I think that "ideal consequentialism" might be a better term for this system, since it isn't just about aggregating utility functions.

What are some of the ideals that an ideal consequentialist theory of population ethics might seek to promote? I've already hinted at what I think they are: Life, consciousness, and activity; health and strength; pleasures and satisfactions of all or certain kinds; happiness, beatitude, contentment, etc.; truth; knowledge and true opinions of various kinds, understanding, wisdom... mutual affection, love, friendship, cooperation; all those other important human universals, plus all the stuff in the Fun Theory Sequence. When considering what sort of creatures to create we ought to create creatures that value those things. Not necessarily, all of them, or in the same proportions, for diversity is an important ideal as well, but they should value a great many of those ideals.

Now, lest you worry that this theory has any totalitarian implications, let me make it clear that I am not saying we should force these values on creatures that do not share them. Forcing a paperclip maximizer to pretend to make friends and love people does not do anything to promote the ideals of Friendship and Love. Forcing a chimpanzee to listen while you read the Sequences to it does not promote the values of Truth and Knowledge. Those ideals require both a subjective and objective component. The only way to promote those ideals is to create a creature that includes them as part of its utility function and then help it maximize its utility.

I am also certainly not saying that there is never any value in creating a creature that does not possess these values. There are obviously many circumstances where it is good to create nonhuman animals. There may even be some circumstances where a paperclip maximizer could be of value. My argument is simply that it is most important to make sure that creatures who value these various ideals exist.

I am also not suggesting that it is morally acceptable to casually inflict horrible harms upon a creature with non-human values if we screw up and create one by accident. If promoting ideals and maximizing utility are separate values then it may be that once we have created such a creature we have a duty to make sure it lives a good life, even if it was a bad thing to create it in the first place. You can't unbirth a child.5

It also seems to me that in addition to having ideals about what sort of creatures should exist, we also have ideals about how utility ought to be concentrated. If this is the case then ideal consequentialism may be able to block some forms of the Repugnant Conclusion, even if situations where the only creatures whose creation is being considered are human beings. If it is acceptable to create humans instead of paperclippers, even if the paperclippers would have higher utility, it may also be acceptable to create ten humans with a utility of ten each instead of a hundred humans with a utility of 1.01 each.

Why Did We Become Convinced that Maximizing Utility was the Sole Good?

Population ethics was, until comparatively recently, a fallow field in ethics. And in situations where there is no option to increase the population, maximizing utility is the only consideration that's really relevant. If you've created creatures that value the right ideals, then all that is left to be done is to maximize their utility. If you've created creatures that do not value the right ideals, there is no value to be had in attempting to force them to embrace those ideals. As I've said before, you will not promote the values of Love and Friendship by creating a paperclip maximizer and forcing it to pretend to love people and make friends.

So in situations where the population is constant, "maximize utility" is a decent approximation of the meaning of right. It's only when the population can be added to that morality becomes much more complicated.

Another thing to blame is human-centric reasoning. When people defend the Repugnant Conclusion they tend to point out that a life barely worth living is not as bad as it would seem at first glance. They emphasize that it need not be a boring life, it may be a life full of ups and downs where the ups just barely outweigh the downs. A life worth living, they say, is a life one would choose to live. Derek Parfit developed this idea to some extent by arguing that there are certain values that are "discontinuous" and that one needs to experience many of them in order to truly have a life worth living.

The Orthogonality Thesis throws all these arguments out the window. It is possible to create an intelligence to execute any utility function, no matter what it is. If human beings have all sorts of complex needs that must be fulfilled in order to for them lead worthwhile lives, then you could create more worthwhile lives by killing the human race and replacing them with something less finicky. Maybe happy cows. Maybe paperclip maximizers. Or how about some creature whose only desire is to live for one second and then die. If we created such a creature and then killed it we would reap huge amounts of utility, for we would have created a creature that got everything it wanted out of life!

How Intuitive is the Mere Addition Principle, Really?

I think most people would agree that morality should exist, and that therefore any system of population ethics should not lead to the Genocidal Conclusion. But which step in the Benign Addition Paradox should we reject? We could reject the step where utility is redistributed. But that seems wrong, most people seem to consider it bad for animals and sociopaths to suffer, and that it is acceptable to inflict at least some amount of disutilities on human beings to prevent such suffering.

It seems more logical to reject the Mere Addition Principle. In other words, maybe we ought to reject the idea that the mere addition of more lives-worth-living cannot make the world worse. And in turn, we should probably also reject the Benign Addition Principle. Adding more lives-worth-living may be capable of making the world worse, even if doing so also slightly benefits existing people. Fortunately this isn't a very hard principle to reject. While many moral philosophers treat it as obviously correct, nearly everyone else rejects this principle in day-to-day life.

Now, I'm obviously not saying that people's behavior in their day-to-day lives is always good, it may be that they are morally mistaken. But I think the fact that so many people seem to implicitly reject it provides some sort of evidence against it.

Take people's decision to have children. Many people choose to have fewer children than they otherwise would because they do not believe they will be able to adequately care for them, at least not without inflicting large disutilities on themselves. If most people accepted the Mere Addition Principle there would be a simple solution for this: have more children and then neglect them! True, the children's lives would be terrible while they were growing up, but once they've grown up and are on their own there's a good chance they may be able to lead worthwhile lives. Not only that, it may be possible to trick the welfare system into giving you money for the children you neglect, which would satisfy the Benign Addition Principle.

Yet most people choose not to have children and neglect them. And furthermore they seem to think that they have a moral duty not to do so, that a world where they choose to not have neglected children is better than one that they don't. What is wrong with them?

Another example is a common political view many people have. Many people believe that impoverished people should have fewer children because of the burden doing so would place on the welfare system. They also believe that it would be bad to get rid of the welfare system altogether. If the Benign Addition Principle were as obvious as it seems, they would instead advocate for the abolition of the welfare system, and encourage impoverished people to have more children. Assuming most impoverished people live lives worth living, this is exactly analogous to the BAP, it would create more people, while benefiting existing ones (the people who pay less taxes because of the abolition of the welfare system).

Yet again, most people choose to reject this line of reasoning. The BAP does not seem to be an obvious and intuitive principle at all.

The Genocidal Conclusion is Really Repugnant

There is nearly nothing repugnant than the Genocidal Conclusion. Pretty much the only way a line of moral reasoning could go more wrong would be concluding that we have a moral duty to cause suffering, as an end in itself. This means that it's fairly easy to counter any argument in favor of total utilitarianism that argues the alternative I am promoting has odd conclusions that do not fit some of our moral intuitions, while total utilitarianism does not. Is that conclusion more insane than the Genocidal Conclusion? If it isn't, total utilitarianism should still be rejected.

Ideal Consequentialism Needs a Lot of Work

I do think that Ideal Consequentialism needs some serious ironing out. I haven't really developed it into a logical and rigorous system, at this point it's barely even a rough framework. There are many questions that stump me. In particular I am not quite sure what population principle I should develop. It's hard to develop one that rejects the MAP without leading to weird conclusions, like that it's bad to create someone of high utility if a population of even higher utility existed long ago. It's a difficult problem to work on, and it would be interesting to see if anyone else had any ideas.

But just because I don't have an alternative fully worked out doesn't mean I can't reject Total Utilitarianism. It leads to the conclusion that a world with no love, curiosity, complex challenge, friendship, morality, or any other value the human race holds dear is an ideal, desirable world, if there is a sufficient amount of some other creature with a simpler utility function. Morality should exist, and because of that, total utilitarianism must be rejected as a moral system.


1I have been asked to note that when I use the phrase "utility" I am usually referring to a concept that is called "E-utility," rather than the Von Neumann-Morgenstern utility that is sometimes discussed in decision theory. The difference is that in VNM one's moral views are included in one's utility function, whereas in E-utility they are not. So if one chooses to harm oneself to help others because one believes that is morally right, one has higher VNM utility, but lower E-utility.

2There is a certain argument against the Repugnant Conclusion that goes that, as the steps of the Mere Addition Paradox are followed the world will lose its last symphony, its last great book, and so on. I have always considered this to be an invalid argument because the world of the RC doesn't necessarily have to be one where these things don't exist, it could be one where they exist, but are enjoyed very rarely. The Genocidal Conclusion brings this argument back in force. Creating creatures that can appreciate symphonies and great books is very inefficient compared to creating bunny rabbits pumped full of heroin.

3Total Utilitarianism was originally introduced to population ethics as a possible solution to the Non-Identity Problem. I certainly agree that such a problem needs a solution, even if Total Utilitarianism doesn't work out as that solution.

4I haven't read a lot of Moore, most of my ideas were extrapolated from other things I read on Less Wrong. I just mentioned him because in my research I noticed his concept of "ideal utilitarianism" resembled my ideas. While I do think he was on the right track he does commit the Mind Projection Fallacy a lot. For instance, he seems to think that one could promote beauty by creating beautiful objects, even if there were no creatures with standards of beauty around to appreciate them. This is why I am careful to emphasize that to promote ideals like love and beauty one must create creatures capable of feeling love and experiencing beauty.

5My tentative answer to the question Eliezer poses in "You Can't Unbirth a Child" is that human beings may have a duty to allow the cheesecake maximizers to build some amount of giant cheesecakes, but they would also have a moral duty to limit such creatures' reproduction in order to spare resources to create more creatures with humane values.

EDITED: To make a point about ideal consequentialism clearer, based on AlexMennen's criticisms.

Personal Blog