What I defend is that, in the absence of a good argument based on welfare ranges and not p(sentience), we don’t know if the welfare range of simpler animals is below or above the bar above which their welfare would dominate over that of more complex animals (not that it is below!).
I suspect we disagree about how it is reasonable to apportion probabilities in the absence of empirical evidence. I think that conditioning on p(sentience) is sufficient to justify a non-negligible probability of similar levels of welfare range in the absence of any further empirical evidence. The empirical evidence that shrimp have small brains detracts from this probability, but not by much. That evidence makes it much more likely that they are not sentient at all, not much more likely that they only feel small feelings.
The empirical evidence that shrimp have small brains detracts from this probability, but not by much.
I very much agree that pretty much whatever our prior should be, the available evidence does not justify substantially updating away from it. I’m just uncertain about what the prior should be (see below).
I think that conditioning on p(sentience) is sufficient to justify a non-negligible probability of similar levels of welfare range in the absence of any further empirical evidence.
Yeah, agreed that’s the crux! :) I think you are applying a principle of indifference (POI) across welfare subjects (or have a significant credence in such a move, at least).[1] While I actually also have sympathy for something of the sort,[2] it is widely criticized in the literature on cluelessness and decision-making under uncertainty. Here’s a list of challenges and possible responses taken from a rough paper draft of mine on this exact topic:
1. Uncertainty about how to individuate welfare subjects within a “welfare-containing” entity or within a bigger welfare-containing entity this one is part of → important instance of the problem of the many. Research could help us non-arbitrarily individuate (see, e.g., Gottlieb 2022; Fischer et al. 2022; McIntyre forthcoming) but this research may face very similar challenges to that on moral weights (on how much we can update away from whatever our prior is) and not bring us far.
But maybe biting the bullet and accepting some arbitrariness here is the least bad option we’ve got?
2. Why apply POI at the level of welfare subjects or brains rather than at the level of, e.g., cells?
Maybe persons (i.e., welfare subjects) are themselves what is morally relevant rather than their experience moments (see, e.g., Bader 2022), but
we’d need a solution to the non-identity problem.
and an argument for why following our intuition on this is fine but not with moral weights.
3. Why endorse any form of POI to start with? In a complex cluelessness context like the one we’re in when estimating moral weights,[3] the plausibility of POI is infamously contested (see, e.g., this, that, and refs therein). Hence, maybe we can’t use POI to justify a precise prior. Maybe we should favor an imprecise one such as each non-human species = (0, X). (where X = 1 or a bit higher.) (which would lead to agnosticism about whether many interspecies tradeoffs we make are justified).
However, to the extent that people want to reject such agnosticism (for whatever reason), even as an uninformed prior, they have to pick a precise-ish alternative prior. In this case, “everyone counts for (~)one” may be more advisable than the other options. (Wager on the possibility that we can apply POI).
A tl;dr from Claude that I like: ignorance about X’s welfare range doesn’t automatically justify treating X’s welfare as if it equals human welfare — it might just justify suspending judgment. The move from “we don’t know the ratio” to “assume the ratio is 1″ needs much more justification.
One could nitpick that there’s technically no complex cluelessness if we’re truly uninformed and ignore the (conflicting) evidence. But in that case, sure, maybe we can start with POI, but then we update towards agnosticism once we consider evidence, so the POI argument for giving everyone the same moral weight wouldn’t work.
I suspect we disagree about how it is reasonable to apportion probabilities in the absence of empirical evidence. I think that conditioning on p(sentience) is sufficient to justify a non-negligible probability of similar levels of welfare range in the absence of any further empirical evidence. The empirical evidence that shrimp have small brains detracts from this probability, but not by much. That evidence makes it much more likely that they are not sentient at all, not much more likely that they only feel small feelings.
I very much agree that pretty much whatever our prior should be, the available evidence does not justify substantially updating away from it. I’m just uncertain about what the prior should be (see below).
Yeah, agreed that’s the crux! :) I think you are applying a principle of indifference (POI) across welfare subjects (or have a significant credence in such a move, at least).[1] While I actually also have sympathy for something of the sort,[2] it is widely criticized in the literature on cluelessness and decision-making under uncertainty. Here’s a list of challenges and possible responses taken from a rough paper draft of mine on this exact topic:
1. Uncertainty about how to individuate welfare subjects within a “welfare-containing” entity or within a bigger welfare-containing entity this one is part of → important instance of the problem of the many. Research could help us non-arbitrarily individuate (see, e.g., Gottlieb 2022; Fischer et al. 2022; McIntyre forthcoming) but this research may face very similar challenges to that on moral weights (on how much we can update away from whatever our prior is) and not bring us far.
But maybe biting the bullet and accepting some arbitrariness here is the least bad option we’ve got?
2. Why apply POI at the level of welfare subjects or brains rather than at the level of, e.g., cells?
Maybe persons (i.e., welfare subjects) are themselves what is morally relevant rather than their experience moments (see, e.g., Bader 2022), but
we’d need a solution to the non-identity problem.
and an argument for why following our intuition on this is fine but not with moral weights.
3. Why endorse any form of POI to start with? In a complex cluelessness context like the one we’re in when estimating moral weights,[3] the plausibility of POI is infamously contested (see, e.g., this, that, and refs therein). Hence, maybe we can’t use POI to justify a precise prior. Maybe we should favor an imprecise one such as each non-human species = (0, X). (where X = 1 or a bit higher.) (which would lead to agnosticism about whether many interspecies tradeoffs we make are justified).
However, to the extent that people want to reject such agnosticism (for whatever reason), even as an uninformed prior, they have to pick a precise-ish alternative prior. In this case, “everyone counts for (~)one” may be more advisable than the other options. (Wager on the possibility that we can apply POI).
A tl;dr from Claude that I like: ignorance about X’s welfare range doesn’t automatically justify treating X’s welfare as if it equals human welfare — it might just justify suspending judgment. The move from “we don’t know the ratio” to “assume the ratio is 1″ needs much more justification.
See also Dickens and Shepherd et al. (2023), who endorse this move.
Especially as an alternative to defaulting to our intuitions or “invertebrates don’t matter at all until proven otherwise”.
One could nitpick that there’s technically no complex cluelessness if we’re truly uninformed and ignore the (conflicting) evidence. But in that case, sure, maybe we can start with POI, but then we update towards agnosticism once we consider evidence, so the POI argument for giving everyone the same moral weight wouldn’t work.