utilitarian

How to be a deontological consequentialist

PNRJ cognitive science, core principles, ethics, heuristics and biases, politics, public policy , , , , , , , , , ,

Dec 7 JDN 2461017

As is commonly understood, there are two main branches of normative ethics:

  • Deontology, on which morality consists in following rules and fulfilling obligations, and
  • Consequentialism, on which morality consists in maximizing good consequences.

The conflict between them has raged for centuries, with Kantians leading the deontologists and utilitarians leading the consequentialists. Both theories seem to have a lot of good points, but neither can decisively defeat the other.

I think this is because they are both basically correct.

In their strongest forms, deontology and consequentialism are mutually contradictory; but it turns out that you can soften each of them a little bit, and the results become compatible.

To make deontology a little more consequentialist, let’s ask a simple question:

What makes a rule worth following?

I contend that the best answer we have is “because following that rule would make the world better off than not following that rule”. (Even Kantians pretty much have to admit this: What maxim could you will to be an absolute law? Only a law that would yield good outcomes.)

That is, the ultimate justification of a sound deontology would be fundamentally consequentialist.

But lest the consequentialists get too smug, we can also ask them another question, which is a bit subtler:

How do you know which actions will ultimately have good consequences?

Sure, if we were omniscient beings who could perfectly predict the consequences of our actions across the entire galaxy on into the indefinite future, we could be proper act utilitarians who literally choose every single action according to a calculation of the expected utility.

But in practice, we have radical uncertainty about the long-term consequences of our actions, and can generally only predict the immediate consequences.

That leads to the next question:

Would you really want to live in a world where people optimized immediate consequences?

I contend that you would not, that such a world actually sounds like a dystopian nightmare.

Immediate consequences say that if a healthy person walks into a hospital and happens to have compatible organs for five people who need donations, we should kill that person, harvest their organs, and give them to the donors. (This is the organ transplant variant of the Trolley Problem.)

Basically everyone recognizes that this is wrong. But why is it wrong? That’s thornier. One pretty convincing case is that a systematic policy of this kind would undermine trust in hospitals and destroy the effectiveness of healthcare in general, resulting in disastrous consequences far outweighing the benefit of saving those five people. But those aren’t immediate consequences, and indeed, it’s quite difficult to predict exactly how many crazy actions like this it would take to undermine people’s trust in hospitals, just how much it would undermine that trust, or exactly what the consequences of that lost trust would be.

So it seems like it’s actually better to have a rule about this.

This makes us into rule utilitarians, who instead of trying to optimize literally every single action—which requires information we do not have and never will—we instead develop a system of rules that we can follow, heuristics that will allow us to get better outcomes generally even if they can’t be guaranteed to produce the best possible outcome in any particular case.

That is, the output of a sophisticated consequentialism is fundamentally deontological.

We have come at the question of normative ethics from two very different directions, but the results turned out basically the same:

We should follow the rules that would have the best consequences.

The output of our moral theory is rules, like deontology; but its fundamental justification is based on outcomes, like consequentialism.

In my experience, when I present this account to staunch deontologists, they are pretty much convinced by it. They’re prepared to give up the fundamental justification to consequences if it allows them to have their rules.

The resistance I get is mainly from staunch consequentialists, who insist that it’s not so difficult to optimize individual actions, and so we should just do that instead of making all these rules.

So it is to those consequentialists, particularly those who say “rule utilitarianism collapses into act utilitarianism”, to whom the rest of the post is addressed.

First, let me say that I agree.

In the ideal case of omniscient, perfectly-benevolent, perfectly-rational agents, rule utilitarianism mathematically collapses into act utilitarianism. That is a correct theorem.

However, we do not live in the ideal case of omniscient, perfectly-benevolent, perfectly-rational agents. We are not even close to that ideal case; we will never be close to that ideal case. Indeed, I think part of the problem here is that you fail to fully grasp the depth and width of the chasm between here and there. Even a galactic civilization of a quintillion superhuman AIs would still not be close to that ideal case.

Quite frankly, humans aren’t even particularly good at forecasting what will make themselves happy.

There are massive errors and systematic biases in human affective forecasting.

One of the post important biases is impact bias: People systematically overestimate the impact of individual events on their long-term happiness. Some of this seems to be just due to focus: Paying attention to a particular event exaggerates its importance in your mind, and makes it harder for you to recall other events that might push your emotions in a different direction. Another component is called immune neglect: people fail to account for their own capacity to habituate to both pleasant and unpleasant experiences. (This effect is often overstated: It’s a common misconception that lottery winners are no happier than they were before. No, they absolutely are happier, on average; they’re just not as much happier as they predicted themselves to be.)

People also use inconsistent time discounting: $10 today is judged as better than $11 tomorrow, but $10 in 364 days is not regarded as better than $11 in 365 days—so if I made a decision a year ago, I’d want to change it now. (The correct answer, by the way, is to take the $11; a discount rate of 10% per day is a staggering 120,000,000,000,000,000% APR—seriously; check it yourself—so you’d better not be discounting at that rate, unless you’re literally going to die before tomorrow.)

Now, compound that with the fact that different human beings come at the world from radically different perspectives and with radically different preferences.

How good do you think we are at predicting what will make other people happy?

Damn right: We’re abysmal.

Basically everyone assumes that what they want and what they would feel is also what other people will want and feel—which, honestly, explains a lot about politics. As a result, my prediction of your feelings is more strongly correlated with my prediction of my feelings than it is with your actual feelings.

The impact bias is especially strong when forecasting other people’s feelings in response to our own actions: We tend to assume that other people care more about what we do than they actually care—and this seems to be a major source of social anxiety.

People also tend to overestimate the suffering of others, and are generally willing to endure more pain than they are willing to inflict upon others. (This one seems like it might be a good thing!)

Even when we know people well, we can still be totally blindsided by their emotional reactions. We’re just really awful at this.

Does this just mean that morality is hopeless? We have no idea what we’re doing?

Fortunately, no. Because while no individual can correctly predict or control the outcomes of particular actions, the collective action of well-designed institutions can in fact significantly improve the outcomes of policy.

This is why we have things like the following:

  • Laws
  • Courts
  • Regulations
  • Legislatures
  • Constitutions
  • Newspapers
  • Universities

These institutions—which form the backbone of liberal democracy—aren’t simply arbitrary. They are the result of hard-fought centuries, a frothing, volatile, battle-tested mix of intentional design and historical evolution.

Are these institutions optimal? Good heavens, no!

But we have no idea what optimal institutions look like, and probably never will. (Those galaxy-spanning AIs will surely have a better system than this; but even theirs probably won’t be optimal.) Instead, what we are stuck with are the best institutions we’ve come up with so far.

Moreover, we do have very clear empirical evidence at this point that some form of liberal democracy with a mixed economy is the best system we’ve got so far. One can reasonably debate whether Canada is doing better or worse than France, or whether the system in Denmark could really be scaled to the United States, or just what the best income tax rates are; but there is a large, obvious, and important difference between life in a country like Canada or Denmark and life in a country like Congo or Afghanistan.

Indeed, perhaps there is no better pair to compare than North and South Korea: Those two countries are right next to each other, speak the same language, and started in more or less the same situation; but the south got good institutions and the north got bad ones, and now the difference between them couldn’t be more stark. (Honestly, this is about as close as we’re ever likely to get of a randomized controlled experiment in macroeconomics.)

People in South Korea now live about as well as some of the happiest places in the world; their GDP per capita PPP is about $65,000 per year, roughly the same as Canada. People in North Korea live about as poorly as it is possible for humans to live, subject to totalitarian oppression and living barely above subsistence; their GDP per capita PPP is estimated to be $600 per year—less than 1% as much.

The institutions of South Korea are just that much better.

Indeed, there’s one particular aspect of good institutions that seems really important, yet is actually kind of hard to justify in act-utilitarian terms:

Why is freedom good?

A country’s level of freedom is almost perfectly correlated with its overall level of happiness and development. (Yes, even on this measure, #ScandinaviaIsBetter.)

But why? In theory, letting people do whatever they want could actually lead to really bad outcomes—and indeed, occasionally it does. There’s even a theorem that liberty is incompatible with full Pareto-efficiency. But all the countries with the happiest people seem to have a lot of liberty, and indeed the happiest ones seem to have the most. How come?

My answer:

Personal liberty is a technology for heuristic utility maximization.

In the ideal case, we wouldn’t really need personal liberty; you could just compel everyone to do whatever is optimal all the time, and that would—by construction—be optimal. It might even be sort of nice: You don’t need to make any difficult decisions, you can just follow the script and know that everything will turn out for the best.

But since we don’t know what the optimal choice is—even in really simple cases, like what you should eat for lunch tomorrow—we can’t afford to compel people in this way. (It would also be incredibly costly to implement such totalitarian control, but that doesn’t stop some governments from trying!)

Then there are disagreements: What I think is optimal may not be what you think is optimal, and in truth we’re probably both wrong (but one of us may be less wrong).

And that’s not even getting into conflicts of interest: We aren’t just lacking in rationality, we’re also lacking in benevolence. Some people are clearly much more benevolent than others, but none of us are really 100% selfless. (Sadly, I think some people are 100% selfish.)

In fact, this is a surprisingly deep question:

Would the world be better if we were selfless?

Could there be actually some advantage in aggregate to having some degree of individual self-interest?

Here are some ways that might hold, just off the top of my head:

  • Partial self-interest supports an evolutionary process of moral and intellectual development that otherwise would be stalled or overrun by psychopaths—see my post on Rousseaus and Axelrods
  • Individuals have much deeper knowledge of their own preferences than anyone else’s, and thus can optimize them much better. (Think about it: This is true even of people you know very well. Otherwise, why would we ever need to ask our spouses one of the most common questions in any marriage: “Honey, what do you want for dinner tonight?”)
  • Self-interest allows for more efficient economic incentives, and thus higher overall productivity.

Of course, total selfishness is clearly not optimal—that way lies psychopathy. But some degree of selfishness might actually be better for long-term aggregate outcomes than complete altruism, and this is to some extent an empirical question.

Personal liberty solves a lot of these problems: Since people are best at knowing their own preferences, let people figure out on their own what’s good for them. Give them the freedom to live the kind of life they want to live, within certain reasonable constraints to prevent them from causing great harm to others or suffering some kind of unrecoverable mistake.

This isn’t exactly a new idea; it’s basically the core message of John Stuart Mill’s On Liberty (which I consider a good candidate for the best book every written—seriously, it beats the Bible by a light-year). But by putting it in more modern language, I hope to show that deontology and consequentialism aren’t really so different after all.

And indeed, for all its many and obvious flaws, freedom seems to work pretty well—at least as well as anything we’ve tried.

Against average utilitarianism

PNRJ core principles, ethics , , , , , , , , , , , , , , , , , , , ,

Jul 30 JDN 2460156

Content warning: Suicide and suicidal ideation

There are two broad strands of utilitarianism, known as average utilitarianism and total utilitarianism. As utilitarianism, both versions concern themselves with maximizing happiness and minimizing suffering. And for many types of ethical question, they yield the same results.

Under average utilitarianism, the goal is to maximize the average level of happiness minus suffering: It doesn’t matter how many people there are in the world, only how happy they are.

Under total utilitarianism, the goal is to maximize the total level of happiness minus suffering: Adding another person is a good thing, as long as their life is worth living.

Mathematically, its the difference between taking the sum of net happiness (total utilitarianism), and taking that sum and dividing it by the population (average utilitarianism).

It would make for too long a post to discuss the validity of utilitarianism in general. Overall I will say briefly that I think utilitarianism is basically correct, but there are some particular issues with it that need to be resolved, and usually end up being resolved by heading slightly in the direction of a more deontological ethics—in short, rule utilitarianism.

But for today, I want to focus on the difference between average and total utilitarianism, because average utilitarianism is a very common ethical view despite having appalling, horrifying implications.

Above all: under average utilitarianism, if you are considering suicide, you should probably do it.

Why? Because anyone who is considering suicide is probably of below-average happiness. And average utilitarianism necessarily implies that anyone who expects to be of below-average happiness should be immediately killed as painlessly as possible.

Note that this does not require that your life be one of endless suffering, so that it isn’t even worth going on living. Even a total utilitarian would be willing to commit suicide, if their life is expected to be so full of suffering that it isn’t worth going on.

Indeed, I suspect that most actual suicidal ideation by depressed people takes this form: My life will always be endless suffering. I will never be happy again. My life is worthless.

The problem with such suicidal ideation is not the ethical logic, which is valid: If indeed your existence from this point forward would be nothing but endless suffering, suicide actually makes sense. (Imagine someone who is being held in a dungeon being continually mercilessly tortured with no hope of escape; it doesn’t seem unreasonable for them to take a cyanide pill.) The problem is the prediction, which says that your life from this point forward will be nothing but endless suffering. Most people with depression do, eventually, feel better. They may never be quite as happy overall as people who aren’t depressed, but they do, in fact, have happy times. And most people who considered suicide but didn’t go through with it end up glad that they went on living.

No, an average utilitarian says you should commit suicide as long as your happiness is below average.

We could be living in a glorious utopia, where almost everyone is happy almost all the time, and people are only occasionally annoyed by minor inconveniences—and average utilitarianism would say that if you expect to suffer a more than average rate of such inconveniences, the world would be better off if you ceased to exist.

Moreover, average utilitarianism says that you should commit suicide if your life is expected to get worse—even if it’s still going to be good, adding more years to your life will just bring your average happiness down. If you had a very happy childhood and adulthood is going just sort of okay, you may as well end it now.

Average utilitarianism also implies that we should bomb Third World countries into oblivion, because their people are less happy than ours and thus their deaths will raise the population average.

Are there ways an average utilitarian can respond to these problems? Perhaps. But every response I’ve seen is far too weak to resolve the real problem.

One approach would be to say that the killing itself is bad, or will cause sufficient grief as to offset the loss of the unhappy person. (An average utilitarian is inherently committed to the claim that losing an unhappy person is itself an inherent good. There is something to be offset.)

This might work for the utopia case: The grief from losing someone you love is much worse than even a very large number of minor inconveniences.

It may even work for the case of declining happiness over your lifespan: Presumably some other people would be sad to lose you, even if they agreed that your overall happiness is expected to gradually decline. Then again, if their happiness is also expected to decline… should they, too, shuffle off this mortal coil?

But does it work for the question of bombing? Would most Americans really be so aggrieved at the injustice of bombing Burundi or Somalia to oblivion? Most of them don’t seem particularly aggrieved at the actual bombings of literally dozens of countries—including, by the way, Somalia. Granted, these bombings were ostensibly justified by various humanitarian or geopolitical objectives, but some of those justifications (e.g. Kosovo) seem a lot stronger than others (e.g. Grenada). And quite frankly, I care more about this sort of thing than most people, and I still can’t muster anything like the same kind of grief for random strangers in a foreign country that I feel when a friend or relative dies. Indeed, I can’t muster the same grief for one million random strangers in a foreign country that I feel for one lost loved one. Human grief just doesn’t seem to work that way. Sometimes I wish it did—but then, I’m not quite sure what our lives would be like in such a radically different world.

Moreover, the whole point is that an average utilitarian should consider it an intrinsically good thing to eliminate the existence of unhappy people, as long as it can be done swiftly and painlessly. So why, then, should people be aggrieved at the deaths of millions of innocent strangers they know are mostly unhappy? Under average utilitarianism, the greatest harm of war is the survivors you leave, because they will feel grief—so your job is to make sure you annihilate them as thoroughly as possible, presumably with nuclear weapons. Killing a soldier is bad as long as his family is left alive to mourn him—but if you kill an entire country, that’s good, because their country was unhappy.

Enough about killing and dying. Let’s talk about something happier: Babies.

At least, total utilitarians are happy about babies. When a new person is brought into the world, a total utilitarian considers this a good thing, as long as the baby is expected to have a life worth living and their existence doesn’t harm the rest of the world too much.

I think that fits with most people’s notions of what is good. Generally the response when someone has a baby is “Congratulations!” rather than “I’m sorry”. We see adding another person to the world as generally a good thing.

But under average utilitarianism, babies must reach a much higher standard in order to be a good thing. Your baby only deserves to exist if they will be happier than average.

Granted, this is the average for the whole world, so perhaps First World people can justify the existence of their children by pointing out that unless things go very badly, they should end up happier than the world average. (Then again, if you have a family history of depression….)

But for Third World families, quite the opposite: The baby may well bring joy to all around them, but unless that joy is enough to bring someone above the global average, it would still be better if the baby did not exist. Adding one more person of moderately-low happiness will just bring the world average down.

So in fact, on a global scale, an average utilitarian should always expect that babies are nearly as likely to be bad as they are good, unless we have some reason to think that the next generation would be substantially happier than this one.

And while I’m not aware of anyone who sincerely believes that we should nuke Third World countries for their own good, I have heard people speak this way about population growth in Third World countries: such discussions of “overpopulation” are usually ostensibly about ecological sustainability, even though the ecological impact of First World countries is dramatically higher—and such talk often shades very quickly into eugenics.

Of course, we wouldn’t want to say that having babies is always good, lest we all be compelled to crank out as many babies as possible and genuinely overpopulate the world. But total utilitarianism can solve this problem: It’s worth adding more people to the world unless the harm of adding those additional people is sufficient to offset the benefit of adding another person whose life is worth living.

Moreover, total utilitarianism can say that it would be good to delay adding another person to the world, until the situation is better. Potentially this delay could be quite long: Perhaps it is best for us not to have too many children until we can colonize the stars. For now, let’s just keep our population sustainable while we develop the technology for interstellar travel. If having more children now would increase the risk that we won’t ever manage to colonize distant stars, total utilitarianism would absolutely say we shouldn’t do it.

There’s also a subtler problem here, which is that it may seem good for any particular individual to have more children, but the net result is that the higher total population is harmful. Then what I think is happening is that we are unaware of, or uncertain about, or simply inattentive to, the small harm to many other people caused by adding one new person to the world. Alternatively, we may not be entirely altruistic, and a benefit that accrues to our own family may be taken as greater than a harm that accrues to many other people far away. If we really knew the actual marginal costs and benefits, and we really agreed on that utility function, we would in fact make the right decision. It’s our ignorance or disagreement that makes us fail, not total utilitarianism in principle. In practice, this means coming up with general rules that seem to result in a fair and reasonable outcome, like “families who want to have kids should aim for two or three”—and again we’re at something like rule utilitarianism.

Another case average utilitarianism seems tempting is in resolving the mere addition paradox.

Consider three possible worlds, A, B, and C:

In world A, there is a population of 1 billion, and everyone is living an utterly happy, utopian life.

In world B, there is a population of 1 billion living in a utopia, and a population of 2 billion living mediocre lives.

In world C, there is a population of 3 billion living good, but not utopian, lives.

The mere addition paradox is that, to many people, world B seems worse than world A, even though all we’ve done is add 2 billion people whose lives are worth living.

Moreover, many people seem to think that the ordering goes like this:


World B is better than world A, because all we’ve done is add more people whose lives are worth living.

World C is better than world B, because it’s fairer, and overall happiness is higher.

World A is better than world C, because everyone is happier, and all we’ve done is reduce the population.


This is intransitive: We have A > C > B > A. Our preferences over worlds are incoherent.

Average utilitarianism resolves this by saying that A > C is true, and C > B is true—but it says that B > A is false. Since average happiness is higher in world A, A > B.

But of course this results in the conclusion that if we are faced with world B, we should do whatever we can to annihilate the 2 billion extra unhappy people, so that we can get to world A. And the whole point of this post is that this is an utterly appalling conclusion we should immediately reject.

What does total utilitarianism say? It says that indeed C > B and B > A, but it denies that A > C. Rather, since there are more people in world C, it’s okay that people aren’t quite as happy.

Derek Parfit argues that this leads to what he calls the “repugnant conclusion”: If we keep increasing the population by a large amount while decreasing happiness by a small amount, the best possible world ends up being one where population is utterly massive but our lives are only barely worth living.

I do believe that total utilitarianism results in this outcome. I can live with that.

Under average utilitarianism, the best possible world is precisely one person who is immortal and absolutely ecstatic 100% of the time. Adding even one person who is not quite that happy will make things worse.

Under total utilitarianism, adding more people who are still very happy would be good, even if it makes that one ecstatic person a bit less ecstatic. And adding more people would continue to be good, as long as it didn’t bring the average down too quickly.

If you find this conclusion repugnant, as Parfit does, I submit that it is because it is difficult to imagine just how large a population we are talking about. Maybe putting some numbers on it will help.

Let’s say the happiness level of an average person in the world today is 35 quality-adjusted life years—our life expectancy of 70, times an average happiness level of 0.5.

So right now we have a world of 8 billion people at 35 QALY, for a total of 280 TQALY. (That’s tera-QALY, 1 trillion QALY.)

(Note: I’m not addressing inequality here. If you believe that a world where one person has 100 QALY and another has 50 QALY is worse than one where both have 75 QALY, you should adjust your scores accordingly—which mainly serves to make the current world look worse, due to our utterly staggering inequality. In fact I think I do not believe this—in my view, the problem is not that happiness is unequal, but that staggering inequality of wealth makes much greater suffering among the poor in exchange for very little happiness among the rich.)

Average utilitarianism says that we should eliminate the less happy people, so we can raise the average QALY higher, maybe to something like 60. I’ve already said why I find this appalling.

So now consider what total utilitarianism asks of us. If we could raise that figure above 280 TQALY, we should. Say we could increase our population to 10 billion, at the cost of reducing average happiness to 30 QALY; should we? Yes, we should, because that’s 300 TQALY.

But notice that in this scenario we’re still 85% as happy as we were. That doesn’t sound so bad. Parfit is worried about a scenario where our lives are barely worth living. So let’s consider what that would require.

“Barely worth living” sounds like maybe 1 QALY. This wouldn’t mean we all live exactly one year; that’s not sustainable, because babies can’t have babies. So it would be more like a life expectancy of 33, with a happiness of 0.03—pretty bad, but still worth living.

In that case, we would need to raise our population over 800 billion to make it better than our current existence. We must colonize at least 100 other planets and fill them as full as we’ve filled Earth.

In fact, I think this 1 QALY life was something like that human beings had at the dawn of agriculture (which by some estimates was actually worse than ancient hunter-gatherer life; we were sort of forced into early agriculture, rather than choosing it because it was better): Nasty, brutish, and short, but still, worth living.

So, Parfit’s repugnant conclusion is that filling 100 planets with people who live like the ancient Babylonians would be as good as life on Earth is now? I don’t really see how this is obviously horrible. Certainly not to the same degree that saying we should immediately nuke Somalia is obviously horrible.

Moreover, total utilitarianism absolutely still says that if we can make those 800 billion people happier, we should. A world of 800 billion people each getting 35 QALY is 100 times better than the way things are now—and doesn’t that seem right, at least?


Yet if you indeed believe that copying a good world 100 times gives you a 100 times better world, you are basically committed to total utilitarianism.

There are actually other views that would allow you to escape this conclusion without being an average utilitarian.

One way, naturally, is to not be a utilitarian. You could be a deontologist or something. I don’t have time to go into that in this post, so let’s save it for another time. For now, let me say that, historically, utilitarianism has led the charge in positive moral change, from feminism to gay rights, from labor unions to animal welfare. We tend to drag stodgy deontologists kicking and screaming toward a better world. (I vaguely recall an excellent tweet on this, though not who wrote it: “Yes, historically, almost every positive social change has been spearheaded by utilitarians. But sometimes utilitarianism seems to lead to weird conclusions in bizarre thought experiments, and surely that’s more important!”)

Another way, which has gotten surprisingly little attention, is to use an aggregating function that is neither a sum nor an average. For instance, you could add up all utility and divide by the square root of population, so that larger populations get penalized for being larger, but you aren’t simply trying to maximize average happiness. That does seem to still tell some people to die even though their lives were worth living, but at least it doesn’t require us to exterminate all who are below average. And it may also avoid the conclusion Parfit considers repugnant, by making our galactic civilization span 10,000 worlds. Of course, why square root? Why not a cube root, or a logarithm? Maybe the arbitrariness is why it hasn’t been seriously considered. But honestly, I think dividing by anything is suspicious; how can adding someone else who is happy ever make things worse?

But if I must admit that a sufficiently large galactic civilization would be better than our current lives, even if everyone there is mostly pretty unhappy? That’s a bullet I’m prepared to bite. At least I’m not saying we should annihilate everyone who is unhappy.