A few days ago Bryan Caplan wondered why economists question whether bringing someone into existence makes them better off, and I had some objections. Bryan has offered up a useful response, in which I think he has inadvertently answered his own question.
He responds to two of my challenges, in which I broadly claimed that if he were right, it would be a moral imperative which would trump all others to bring as many people into existence as possible, which seemed to violate common sense morality. He agrees that this is a bullet to bite for strict utilitarians, but adherents to other moral positions can rationalize not having to behave with an observation that begins “People who actually exist count a lot more than people who could exist but don’t.” This, however, answers the question he asked in the first place, which was:
If someone gives another person the gift of life, however, I’ve noticed that many economists suddenly become agnostic. $100? Definitely an improvement. Being alive? Meh.
It’s hard to see the logic. Why would a minor gift of cash be a clear-cut gain, but a massive gift of human capital be a question mark?
Understanding that the cash gift makes someone better off requires nothing more than strict utilitarianism, the mode of analysis economists are trained in. The gift of life however requires something more than strict utilitarianism, and requires some other moral position to justify it. Furthermore, it’s hard to think of a reasonable moral position according to which giving someone $100 does not make them better, whereas it is not so hard to imagine reasonable moral positions according to which the gift of life does not make someone better off. One is clear-cut and requires the usual tools of economic analysis, the other is not and requires appealing to other moral positions.
Elsewhere, and speaking of bullet biting utilitarians, Robin Hanson outlines an economic analysis of which creatures should exist and which shouldn’t. But I think Robin has some big unspoken assumptions in his analysis. The general problem is we don’t know the preferences of the non-existent. Here is how Robin broadly describes how the analysis of which creatures should exist should be done:
Economically, creature X should exist if it wants to exist and it can pay for itself. That is, in a supply and demand world, if our only choice is whether X should exist, then an X that wants to exist should actually exist if its lifespan cost of resources used (including paying for any net externalities) is no more than the value it gives by working for others.
The problem is that we don’t know the preferences of the non-existent, and so we don’t know Robin’s first requirement: whether creature X wants to exist. Not only that, but according to Robin’s efficiency criteria you have to know whether they prefer an existence conditional on that existence includes paying their costs, and not just existing as a freeloader. You could argue that we could poll the existing and see if they would have preferred to never exist, but we don’t know whether the preferences of the non-existent have any relationship at all to the existing. In addition, for many creatures we have no way to do even this post-existence polling. How do you understand a dogs preferences for existing versus never existing? And remember, showing a preference for continuing to exist over ceasing to existing is not the same as preferring to existing over never existing.
The problem with both of their analysis is the preferences for existing versus never existing are facts simply knowable through economic analysis, and must be brought from somewhere else. That is why, contra Bryan, I don’t think the value of the gift of life is not clear-cut to economists as the value of a $100 gift, and contra Robin, I don’t think knowing which creatures should exist is amenable to cost-benefit analysis.
I should add that, probabilistically, by simultaneously disagreeing with Robin Hanson and Bryan Caplan, I recognize I am likely wrong. So if I were to bet on these propositions, I would bet against them.

15 comments
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Tuesday ~ August 31st, 2010 at 11:33 pm
jazzbumpa
I’m astounded at the amount of mental effort you’ve put into this ultimately meaningless, frivolous, pointless, fatuous exercise.
As I pointed out in what I think was your first post on this subject, nonexistence is a null state. This is a simple and obvious identity.
The problem is that we don’t know the preferences of the non-existent,
As incredible as it seems, you must mean this statement seriously, since you said it twice. But, you see, the non-existent have no preferences since THEY DON’T EXIST.
Please re-read the previous sentence as many times as it takes for it to sink in.
Now, I must go hug a squid.
JzB
Wednesday ~ September 1st, 2010 at 8:28 am
Adam Ozimek
You’re sort of agreeing with me. To do cost-benefit you need to know the utility in both states (E and NE) and the preferences. Since those things are at best undefined for NE, you can’t do cost-benefit.
Tuesday ~ August 31st, 2010 at 11:38 pm
Robin Hanson
Surely there are many kinds of creatures where we could know with great confidence that they prefer to exist. Exact copies of other already existing creatures, for example. Can you accept that these creatures should exist?
Wednesday ~ September 1st, 2010 at 3:11 am
RickRussellTX
I believe JazzBumpa is on the right track. Look at it as a very simple “if p then q” logic problem.
If x does not exist, then x prefers to exist.
If x does not exist, then x prefers not to exist.
Neither statement can be true, since the definition of “exist” precludes the selection of an x that satisfies the description “does not exist”.
In direct reply to Mr. Hanson, I would say that no, I cannot determine the preferences of “exact copies of other already existing creatures”, because these exact copies do not exist. Neither can I accept that they “should exist”.
If you could create such a copy, I would readily admit that we can know its preferences, but it no longer resides in the set of creatures that do not exist. It exists, precluding it from our discussion of the preferences of the non-existent.
Wednesday ~ September 1st, 2010 at 7:50 am
Adam Ozimek
No, because we can’t know the creatures preferences for E (existing) over NE (never existing), since we can’t observe the preferences of the NE. Also, even if you take the E creatures stated preferences as proxy for that creature in a NE state, that limits you to the using cost benefit for creatures able to express their preferences for E vs NE. But doing so requires an assumption about preferences that takes you beyond cost-benefit and into philosophy.
Wednesday ~ September 1st, 2010 at 2:28 pm
RickRussellTX
“Sir, before you existed, what was your preference for existence?”
Even the “exact copies of already existing creatures” example has this problem; we can only determine their preferences in the existent state.
I think the only thing we can say about the non-existent exact copy of a creature is that its preferences are undefined, or perhaps that the concept of “preference” has no meaning when applied to a set which has no members.
Equally pressing and precisely equivalent questions would be, “If x does not exist, does it need to pee?” or “If x does not exist, does it like Pop-Tarts?”
Phrased in that sense, the question is clearly meaningless.
Tuesday ~ August 31st, 2010 at 11:50 pm
Sister Y
I like RH’s definition of who should exist – remarkably like R.M. Hare’s famous words on abortion. But:
“we don’t know whether the preferences of the non-existent have any relationship at all to the existing”
Yes. Exactly this. Thank you! Polling already existing beings is not a good proxy for finding the preferences of not-yet-existing beings. (And preferring existence, even a posteriori, is not unanimous. Even a fraction of lives ending in suicide should give us pause about the reproduction project, I think.)
On a positive note, at least RH and BC seem to be occupying a position in favor of suicide rights. Almost the only time I hear people suggest suicide as an option is when faced with the nasty problem of bringing nonconsenting beings into existence.
Wednesday ~ September 1st, 2010 at 9:37 am
Noumenon
I would bet against almost any proposition endorsed by Brian Caplan, actually…
Wednesday ~ September 1st, 2010 at 10:52 am
CM
Very good posts. I cannot believe anyone takes Bryan Kaplan seriously on these issues. Why are there so many economists who have internalized the naturalistic fallacy?
What do preferences matter, anyway? It is not sound to use a future preference to justify a current action (especially when the being who would hold the preference doesn’t even exist!). Plus, what Curator said about R.M. Hare. If I become a heroin addict, I will have a preference for heroin. Should I become a heroin addict, then? Never mind the fact that my countless other preferences would be frustrated as a result (kind of like in life). We also cannot use current heroin addicts’ preference for heroin as evidence that becoming heroin addicts was good for them.
Existence has no intrinsic value. It simply provides an opportunity for such values, and none of them are guaranteed. So equating breeders with philanthropists is thoroughly misguided, even if we ignore the obvious fact that existence does come with some pretty major guaranteed flaws.
Wednesday ~ September 1st, 2010 at 11:06 am
CM
Bryan Caplan, that is:)
Wednesday ~ September 1st, 2010 at 12:21 pm
Rebecca Burlingame
Now I hope this has been settled and the guys are tired of arguing – economically that is – how many angels are dancing on the head of a pin. Sister Y, I do like the mention of suicide rights, it almost never is there. Let’s go back to the original matter for a moment, as I said the value of $100 is presently economically “better” than the human life. What I did not mention previously in this argument is…why is that even necessary? We only have to give the right of true wealth creation to human potential, and the knowing that knowledge has the capacity to be an infinite resource. By so doing human life would be worth far more than any silly $100 bill.
Wednesday ~ September 1st, 2010 at 5:27 pm
blokeinfrance
All life strives to exist. But that’s not a preference, it’s a compulsion. Compulsion allows for no alternative, so inventing alternatives is splitting hairs. (Not that I haven’t been amused by the hares started by this discussion…)
Wednesday ~ September 1st, 2010 at 5:39 pm
Sister Y
What if we could create creatures that are completely miserable and suffer piteously all their long lives, except . . . we can endow them with a preference to exist?
Kinda like what natural selection has done for us humans.
Wednesday ~ September 1st, 2010 at 8:50 pm
Robin Hanson
I seems odd that I have to specify this in such detail, but here goes: For some creatures we know with great confidence that *if* they existed, they would prefer to exist. I now prefer to exist, for example. Those are the creatures I suggest creating, if they can pay for their existence.
Saturday ~ September 11th, 2010 at 12:03 pm
Ignorance of non-existent preferences | Meteuphoric
[...] Ignorance of non-existent preferences Posted on September 12, 2010 by Katja Grace| Leave a comment I often hear it said that since you can’t know what non existent people or creatures want, you can’t count bringing them into existence as a benefit to them even if you guess they will probably like it. For instance Adam Ozimek makes this argument here. [...]