The version of negative utilitarianism I have in mind is not one that ignores net-positive lives, but one that denies their existence in principle, so the ui live in R−.
It’s easier to see in a preference framework: for a fixed set of preferences, maximising preference satisfaction is exactly the same as minimising preference frustration. But as soon as we can change the set of preferences, those two approaches are radically different. Those forms of NU are about minimising the amount of frustrated preferences, which can only be positive in principle. Or, equivalently, about maximising the opposite of that, which is always negative. This satisfies aggregation and Pareto axioms.
Ah, ok. Well, if then we still have TU on that set, it would satisfy all of the axioms including Aggregation, so Theorem 1 would apply, but I suppose you have some sort of asterisk that the A and Z populations (large perfectly-equal populations in which everyone has a positive (if slightly) life) are part of an impossible subset of the imaginable set of populations.
But of course the A and Z populations are already impossible, because we already have present and past lives that aren’t perfectly equal and aren’t all worth living. So—even setting aside possible boundedness on the number of lives—the RC has always fundamentally been about comparing undeniably impossible populations. That, of course, is yet another reason why we might downgrade the importance of the RC in our decisions about what to believe and do.
But of course the A and Z populations are already impossible, because we already have present and past lives that aren’t perfectly equal and aren’t all worth living. So—even setting aside possible boundedness on the number of lives—the RC has always fundamentally been about comparing undeniably impossible populations
I don’t find this a compelling response to Guillaume’s objection. There seems to be a philosophically relevant difference between physical impossibility of the populations, and metaphysical impossibility of the axiological objects. We study population ethics because we expect our decisions about the trajectory of the long-term future to approximate the decisions involved in these thought experiments. So the point is that NU would not prescribe actions with the general structure of “choose a future with arbitrarily many torturous lives and a sufficiently large number of slightly more happy than suffering lives [regardless of whether we call these positive utility lives], over a future with arbitrarily many perfectly happy lives,” but these other axiologies would. (ETA: As Michael noted, there are other intuitively unpalatable actions that NU would prescribe too. But the whole message of this paper is that we need to distinguish between degrees of repugnance to make progress, and for some, the VRC is more repugnant than the conclusions of NU.)
Thank you for your comment!
The version of negative utilitarianism I have in mind is not one that ignores net-positive lives, but one that denies their existence in principle, so the ui live in R−.
It’s easier to see in a preference framework: for a fixed set of preferences, maximising preference satisfaction is exactly the same as minimising preference frustration. But as soon as we can change the set of preferences, those two approaches are radically different. Those forms of NU are about minimising the amount of frustrated preferences, which can only be positive in principle. Or, equivalently, about maximising the opposite of that, which is always negative. This satisfies aggregation and Pareto axioms.
Ah, ok. Well, if then we still have TU on that set, it would satisfy all of the axioms including Aggregation, so Theorem 1 would apply, but I suppose you have some sort of asterisk that the A and Z populations (large perfectly-equal populations in which everyone has a positive (if slightly) life) are part of an impossible subset of the imaginable set of populations.
But of course the A and Z populations are already impossible, because we already have present and past lives that aren’t perfectly equal and aren’t all worth living. So—even setting aside possible boundedness on the number of lives—the RC has always fundamentally been about comparing undeniably impossible populations. That, of course, is yet another reason why we might downgrade the importance of the RC in our decisions about what to believe and do.
I don’t find this a compelling response to Guillaume’s objection. There seems to be a philosophically relevant difference between physical impossibility of the populations, and metaphysical impossibility of the axiological objects. We study population ethics because we expect our decisions about the trajectory of the long-term future to approximate the decisions involved in these thought experiments. So the point is that NU would not prescribe actions with the general structure of “choose a future with arbitrarily many torturous lives and a sufficiently large number of slightly more happy than suffering lives [regardless of whether we call these positive utility lives], over a future with arbitrarily many perfectly happy lives,” but these other axiologies would. (ETA: As Michael noted, there are other intuitively unpalatable actions that NU would prescribe too. But the whole message of this paper is that we need to distinguish between degrees of repugnance to make progress, and for some, the VRC is more repugnant than the conclusions of NU.)