Assuming Rawls’s veil of ignorance, I would prefer to be randomly born in a world where a trillion people lead billion-year lifespans than one in which a quadrillion people lead million-year lifespans.
I agree, but is this the right comparison? Isn’t this framing obscuring the fact that in the trillion-people world, you are much less likely to be born in the first place, in some sense?
Let us try this framing instead: Assume there are a very large number Z of possible different human “persons” (e.g. given by combinatorics on genes and formative experiences). There is a Rawlsian chance of 1/Z that a new created human will be “you”. Behind the veil of ignorance, do you prefer the world to be one with X people living N years (where your chance of being born is X/Z) or the one with 10X people living N/10 years (where your chance of being born is 10X/Z)?
I am not sure this is the right intuition pump, but it seems to capture an aspect of the problem that yours leaves out.
I agree, but is this the right comparison? Isn’t this framing obscuring the fact that in the trillion-people world, you are much less likely to be born in the first place, in some sense?
Rawls’s veil of ignorance + self-sampling assumption = average utilitarianism, Rawls’s veil of ignorance + self-indication assumption = total utilitarianism (so to speak)? I had already kind-of noticed that, but hadn’t given much thought to it.
Doesn’t Rawls’s veil of ignorance prove too much here though? If both worlds would exist anyway, I’d rather be born into a world where a million people lived 101 year lifetimes than a world where 3^^^3 people lived 100 year lifetimes.
So then, Rawls’s veil has to be modified such that you are randomly chosen to be one of a quadrillion people. In scenario A, you live a million years. In scenario B, one trillion people live for one billion years each, the rest are fertilized eggs which for some reason don’t develop.
Would you? A million probably isn’t enough to sustain a modern economy, for example. (Although in the 3^^^3 case it depends on the assumed density since we can only fit a negligible fraction of that many people into our visible universe).
But compared to 3^^^3, it doesn’t matter whether it’s a million people, a billion, or a trillion. You can certainly find a number that is sufficient to sustain an economy and is still vastly smaller than 3^^^3, and you will end up preferring the smaller number for a single additional year of lifespan. Of course, for Rawls, this is a feature, not a bug.
Assuming Rawls’s veil of ignorance, I would prefer to be randomly born in a world where a trillion people lead billion-year lifespans than one in which a quadrillion people lead million-year lifespans.
I agree, but is this the right comparison? Isn’t this framing obscuring the fact that in the trillion-people world, you are much less likely to be born in the first place, in some sense?
Let us try this framing instead: Assume there are a very large number Z of possible different human “persons” (e.g. given by combinatorics on genes and formative experiences). There is a Rawlsian chance of 1/Z that a new created human will be “you”. Behind the veil of ignorance, do you prefer the world to be one with X people living N years (where your chance of being born is X/Z) or the one with 10X people living N/10 years (where your chance of being born is 10X/Z)?
I am not sure this is the right intuition pump, but it seems to capture an aspect of the problem that yours leaves out.
Rawls’s veil of ignorance + self-sampling assumption = average utilitarianism, Rawls’s veil of ignorance + self-indication assumption = total utilitarianism (so to speak)? I had already kind-of noticed that, but hadn’t given much thought to it.
Doesn’t Rawls’s veil of ignorance prove too much here though? If both worlds would exist anyway, I’d rather be born into a world where a million people lived 101 year lifetimes than a world where 3^^^3 people lived 100 year lifetimes.
So then, Rawls’s veil has to be modified such that you are randomly chosen to be one of a quadrillion people. In scenario A, you live a million years. In scenario B, one trillion people live for one billion years each, the rest are fertilized eggs which for some reason don’t develop.
I’d still choose B over A.
Would you? A million probably isn’t enough to sustain a modern economy, for example. (Although in the 3^^^3 case it depends on the assumed density since we can only fit a negligible fraction of that many people into our visible universe).
If the economies would be the same, then yes. Don’t fight the hypothetical.
I think “fighting the hypothetical” is justified in cases where the necessary assumptions are misleadingly inaccurate—which I think is the case here.
But compared to 3^^^3, it doesn’t matter whether it’s a million people, a billion, or a trillion. You can certainly find a number that is sufficient to sustain an economy and is still vastly smaller than 3^^^3, and you will end up preferring the smaller number for a single additional year of lifespan. Of course, for Rawls, this is a feature, not a bug.