To a first approximation, all farmed animals are bugs
To a first approximation, all farmed animals are bugs. (Recalling, of course, that shrimps is bugs.) We don’t know much about their needs in current production systems. The Arthropoda Foundation is trying to fix that. If we want to help the most numerous farmed animals, we have to answer some basic empirical questions. Arthropoda funds the scientists who provide those answers.
Good science isn’t cheap, fast, or flashy. But if we don’t fund it, we’re left guessing about the welfare of the most numerous animals on farms (and in the wild). The stakes are too high for guesswork.
This year, Arthropoda granted out ~$160K to fund seven studies. That’s seven studies for at least a trillion farmed animals. (And untold numbers of wild animals.)
We could easily grant out much more. And with a staff person, we could actively develop projects to support. But as it is, we’re at capacity.
In 2025, Arthropoda cost about $175K, over 90% of which went to grants. The rest covered costs associated with learning more about the state of the industry, running a small coordination event, and legal compliance with charitable regulations. We want to spend at least $205K in 2026. Currently, we’re about $55K short.
Anything toward that $55K is helpful. Anything beyond it means we can scale our grantmaking and field-building efforts. With additional funds, we could support two, three, or four times as many studies. With a part-time staff person (roughly $45K, all in), we could do more active grantmaking.
The elephant (beetle) in the room: Can these animals feel anything?
The question is fair: We have our doubts too. But just for a moment, consider the fruit fly. One research team denied them sleep and sex, finding anxiety-like states that were moderated by anti-anxiety medications. Another team inserted the human capsaicin receptor into fruit flies, laced their food with capsaicin, and then found that they starved to death instead of eating. A third burned them with a probe and discovered that this produced thermal allodynia, or sensitivity to temperatures that weren’t previously noxious (the way even slightly warm water feels scalding on a burn). A fourth research team activated their nociceptors with light to show that they have something like the kind of central gating that’s characteristic of the mammalian pain system. A fifth team manipulated the mechanism that inhibits nociceptive signals from their brains to their ventral nerve cords; the researchers found that, just as in mice and humans, this produced chronic-pain-like symptoms. Each new paper, like this preprint, seems to reaffirm the emerging picture: “Our findings reveal that adult Drosophila satisfy several of the criteria commonly used to define the experience of pain.”
None of this is decisive. At the very least, though, it’s suggestive, and probably justifies more concern for flies than is common. And if flies, why not others?
Please consider supporting the Arthropoda Foundation this Giving Season.
This is a really important write-up, and honestly, more people need to be talking about welfare research for invertebrates. The scale alone makes it impossible to ignore if there’s even a chance these animals experience something like pain, funding good science becomes a moral priority.
The work Arthropoda is doing seems incredibly high-leverage, especially given how little we currently understand. Even modest funding could meaningfully shift an entire field, so supporting them really does feel like one of those “small input, huge impact” opportunities.
I think there are good reasons for funding research on the welfare of soil animals instead of on farmed arthropods at the margin. So I would be curious to know more about how funding Arthropoda could lead to more research on soil animals. Would you recommend funding Arthropoda if all farmed arthropods had a probability of sentience of exactly 0, but the welfare capacity of soil animals was still described by your current views? I guess farmed arthropods are at least 50 % likely to be sentient, but the hypothetical may help assess Arthropoda’s effects on soil animals.
I have donated to Arthropoda in the past. However, I would be surprised if targeting (optimising for increasing the welfare of) farmed arthropods was optimal for increasing the welfare of soil animals. I would target:
Shrimps instead of chickens to increase the welfare of shrimps.
Chickens instead of shrimps to increase the welfare of chickens.
Humans in low income countries (LICs) instead of humans in high income countries (HICs) to increase the welfare of humans in LICs.
Humans in HICs instead of humans in LICs to increase the welfare of humans in HICs.
Chickens instead of dogs to increase the welfare of chickens.
Dogs instead of chickens to increase the welfare of dogs.
AI systems instead of shrimps to increase the welfare of AI systems.
Shrimps instead of AI systems to increase the welfare of shrimps.
I also wonder about how funding Arthropoda compares with funding Wild Animal Initiative (WAI) or The Center for Wild Animal Welfare (CWAW) from the point of view of increasing the welfare of soil animals. On the one hand, soil animals are invertebrates, and Arthropoda funds research on invertebrates, whereas only 9.39 % of the funds granted by WAI have supported projects on invertebrates, and CWAW’s focus on policy may mean their will also primary focus on vertebrates. On the other hand, soil animals are wild animals, and Arthropoda targets farmed animals, whereas WAI and CWAW target wild animals. I believe it would be worth doing research not only on the welfare of soil animals, but also on what are the most cost-effective ways of building capacity for it.
Hi Vasco! As we’ve discussed in other threads/emails/etc, we have different meta-ethical views and different views about consciousness. So I’m not surprised we’ve landed in somewhat different places on this issue :)
Bob and I make most of the strategic and granting decisions for Arthropoda, and we have slightly different views, so I don’t know exactly where we will land (he’ll reply in a second with his thoughts). But broadly, we both agree that we don’t think soil nematodes and some other soil invertebrates have enough likelihood of being sentient to be a high priority, nor do we think that (for those that are sentient) we have a good enough understanding of what would help them to make action-oriented grants (which is Arthropoda’s focus) — in part because we don’t endorse precise-probabilities approaches to handling uncertainty, and so want to make grants that are aimed towards actions that appear robustly positive under a range of possible probability assignments/ways of handling uncertainty.
That said, our confidence in our own position is not high. So, we’d be willing to fund things to challenge our own views: If we had sufficient funding from folks interested in the question, Arthropoda would fund a grant round specifically on soil invertebrate sentience and relevant natural history studies (especially in ways that attempt to capture the likely enormous range of differences between species in this group). Currently, much of our grant-making funds are restricted (at least informally) to farmed insects and shrimp, so it’s not an option.
As a result, I expect that Arthropoda is probably still one of the better bets for soil invertebrate interested donors. As a correction to your comment, Arthropoda is not restricted in focus as a matter of principle, but just has happened for contingent reasons to focus on farmed animals in its first rounds. We collaborate with Wild Animal Initiative (I’m the strategy director at WAI) to reduce duplication of effort, and have a slightly better public profile for running soil invertebrate studies, so we expect it will generally be Arthropoda rather than WAI who would be more likely to run this kind of program. I don’t want to speak for CWAW, so I’ll let them reply if they have interests in this area; but from my own conversations I doubt they would be in a good position to make soil invertebrates a priority in the next couple of years. Finally, you haven’t mentioned them, but Rethink Priorities may also be open to some work in this area (I’m not sure though).
I agree with Mal about Arthropoda being a good bet for this work. RP would be good too. On the macro-level issue of priorities, I’ve gathered some of my thoughts here.
Finally, I’ll say publicly what I’ve said privately: thank you for supporting Arthropoda. It means a lot to me that you donated.
In my mind, given 2 potential states of the worlds, one always has more, the same, or less expected welfare than the other. So I think any 2 potential states of the world are always comparable, although I would agree the vast majority of real comparisons are very uncertain.
In any case, I do not understand why expected welfare being imprecise (as a result of imprecise probabilities) would be a reason for prioritising research on farmed invertebrates over soil animals. Bob says “getting producers to shorten time to death during insect processing or stun farmed shrimp seems robustly good”, but I do not even know whether electrically stunning farmed shrimps increases or decreases animal welfare in expectation due to effects on soil animals. I believe pursuing robustly good actions, at least in the sense of mitigating the risk of decreasing welfare in expectation (amongst other considerarions), will very often require understanding effects on soil animals. I would be curious to know your thoughts on this, @Anthony DiGiovanni.
Thanks for sharing, Bob! I would publish that as a post.
Which are the soil invertebrates whose probability of sentience you think is too low for them to be a high priority? I assume soil nematodes, mites, and springtails, as Bob says “We have nothing like the evidence for sentience in Drosophila for mites, springtails, thrips, and the like”. Do you expect the probability of sentience to drop much more from black soldier fly (BSF) larvae to soil springtails, mites, and nematodes than from chickens to BSF larvae? I do not understand why one would expect this. Gemini guesses (random) soil nematodes, mites, and springtails have 300, 1.1 k, and 3.8 k neurons. Adult nematodes of the species C. elegans have 302 neurons. BSF larvae have 2.3 k to 20 k neurons depending on their stage of development (“L1: 2,300 [brain] cells [neurons]; L6: 20,000 cells”). So I believe BSF larvae have around 11.2 k neurons (= (2.3 + 20)/2*10^3), 37.3 (= 11.2*10^3/300) times those of soil nematodes, 10.2 (= 11.2*10^3/(1.1*10^3)) times those of soil mites, or 2.95 (= 11.2*10^3/(3.8*10^3)) times those of soil springtails. In contrast, chickens, as proxied by the red junglefowl, have 221 M neurons, 19.7 k (= 221*10^6/(11.2*10^3)) those of BSF larvae. In other words, the number of neurons decreases 4.29 (= log10(19.7*10^3)) orders of magnitude (OOMs) from chickens to BSF larvae, but only 0.470 (= log10(2.95)) OOMs from BSF larvae to soil springtails, and 1.10 (= log10(3.8*10^3/300)) OOMs from soil springtails to nematodes. “Number of neurons”^0.188 explains pretty well the welfare ranges in Bob’s book about comparing welfare across species across 6 OOMs of the number of neurons (RP estimated shrimps have 10^-6 as many neurons as humans; see Table 5), as illustrated below. This is many more OOMs than those from BSF larvae to soil springtails, mites, and nematodes.
Bob, do you mean the probability of sentience (or absolute value of the expected individual welfare per animal-year) is proportional to “number of neurons”^a, where a < 1, for a sufficiently high number of neurons, but that such power law dramatically overestimates the probability of sentience of soil nematodes, mites, and springtails? If so, why would the probability of sentience fall off a cliff over the 0.470 OOMs of the number of neurons from BSF larvae to soil springtails, but not over the 6 OOMs from humans to shrimps? I understand there is much less evidence for the sentience of springtails than for that of shrimp or BSFs. However, one should account not only for the evidence available now, but also for what would be found out given further investigation. Some decades ago, someone could have produced the graph above without shrimps and BSFs, and guessed the probability of sentience would fall off a cliff somewhere between carps and shrimps or BSFs, whereas assuming the probability of sentience is a power law of the number of neurons (or other neurophysiological feature) would have predicted much better your results.
Moreover, one should be sensitive not only to differences in the probability of sentience, but also in population, even if one does not strongly endorse maximising expected welfare (as I do). The number of individuals increases astronomically from farmed BSF larvae to soil springtails, mites, and nematodes, but little from chickens to farmed BSF larvae. I estimate there are 83.0 M (= 3.17*10^18/(3.82*10^10)), 166 M (= 6.33*10^18/(3.82*10^10)), and 12.8 billion (= 4.89*10^20/(3.82*10^10)) times as many soil springtails, mites, and nematodes as farmed BSF larvae and mealworms, but only 1.40 (= 3.82*10^10/(2.72*10^10)) times as many farmed BSF larvae and mealworms as chickens.
I’m sorry that I don’t have time to respond to all your questions, Vasco. The short version, though, is that I also want robustness in the case for sentience, so I’m much less inclined to make the kinds of extrapolations you’re suggesting here. I have the same view about our moral weight work: I put very little stock in any specific numbers, as I think that plausible moral weights will be defensible from several angles, each of which will suggest somewhat different estimates, with no obvious right way to aggregate them. (Again, there’s that skepticism about expected value!)
I don’t think the case for Vasco’s argument depends really on sentience in non-arthropods. There are like a billion soil arthropods for every person, so funding research on soil animals looks similarly important. And a lot of these are ants who are more likely to be sentient than black soldier flies.
I do find the comment “I also want robustness in the case for sentience,” a bit puzzling in context. As I understood it, Vasco’s argument was that it’s not very unlikely that animals even simpler than arthropods are sentient (mites, springtails, etc). That there’s not a robust case that they are analogous isn’t a strong argument for them not being analogous (and will, in fact, be a reason for uncertainty and research).
Broadly agree with a lot of the document though, especially the funding stuff! I think funding Arthropoda is great!
I guess you are saying you prefer narrower distributions of the probability of sentience holding the expected probability of sentience constant. This contributes towards you prioritising BSF larvae over soil springtails, mites, and nematodes (all else equal) because there is more uncertainty about the probability of sentience of the latter. What matters for me is expected welfare, which only depends on the expected probability of sentience. However, I think one would have to value narrower distributions of the probability of sentience to an unreasonable amount to prioritise BSF larvae and mealworms over soil springtails, mites, and nematodes if one prioritises farmed BSF larvae and mealworms over chickens. The distribution of the probability of sentience of chickens is much narrower than that of farmed BSF larvae and mealworms, and I estimate the population of farmed BSF larvae and mealworms is just 1.40 times that of chickens (see my last comment). In contrast, I believe the distribution of the probability of sentience of farmed BSF larvae and mealworms is not that much narrower than that of soil springtails, mites, and nematodes, and I estimate the population of soil springtails, mites, and nematodes is 83.0 M, 166 M, and 12.8 billion times that of farmed BSF larvae and mealworms (see my last comment).
Furthermore, I estimate the population of soil ants and termites is 1.31 M (= 5*10^16/(3.82*10^10)) and 2.62 M (= 1*10^17/(3.82*10^10)) times that of farmed BSF larvae and mealworms, and I suspect the probability of sentience of soil ants and termites is both higher in expectation and narrower, as I calculate soil ants and termites have 22.3 (= 250*10^3/(11.2*10^3)) and 8.93 (= 100*10^3/(11.2*10^3)) times as many neurons as BSF larvae and mealworms. In any case, I would prioritise soil ants and termites even if I thought the distribution of the probability of their sentience was much wider than that of farmed BSF larvae and mealworms. I would just focus on research on the sentience of soil ants and termites instead of ways of increasing their welfare.
Me too. Yet, I do not think the points I am making depend on a specific way of comparing welfare across species. I estimate the absolute value of the total welfare of soil animals is many OOMs larger than that of farmed BSF larvae and mealworms for indidividual welfare per animal-year proportional to “number of neurons”^”exponent of the number of neurons”, and this exponent ranging from 0 to 2 (see the 1st graph below), which covers dramatically different welfare ranges (see the 2nd graph below).
Thanks, all. Let me add something that may help clarify why we’re always at loggerheads. I’m not actually thinking about these questions in probabilistic terms at all. In my view, the evidential situation for most arthropods is so sparse that I don’t actually believe we’re in a position to assign meaningful probabilities of sentience—even extremely rough ones. We’re squarely in the domain of the precautionary, not the probabilistic. When the evidence is this patchy and the mechanisms this poorly understood, numerical probability assignments feel more like artifacts of modeling choices than reflections of the world. So, when I talk about “robustness,” I’m not covertly appealing to narrower or wider probability distributions; I’m saying that the entire framework of attaching numbers to these uncertainties feels inappropriate.
This is one of several reasons why focusing on well-studied insects makes sense to me. It’s not that I think BSF larvae are 10× or 100× more likely to be sentient than springtails. It’s that we have a type of evidence for some insects—convergent behavioral, physiological, and neuroanatomical findings—that simply doesn’t exist at all for mites, springtails, and nematodes. And without that evidential base, I’m wary of using a first-pass model to set priorities. Expected value becomes extremely fragile under those conditions, as the inputs aren’t grounded: they’re guesses stacked on guesses.
So the way I think about prioritization has less to do with estimated probabilities and more to do with where precautionary reasoning can actually get traction. Work on farmed and research arthropods produces immediate welfare improvements, helps develop welfare indicators, and builds the scientific ecosystem we’ll need if we ever hope to understand smaller arthropods. That’s a much more stable basis for action than trying to set priorities via BOTECs.
Anyway, we’ll just have to agree to disagree, as we just keep running up against the same issues over and over!
Lastly, this article is good. The possibility the they’re right is one of the things that makes me inclined to see insects as the limit case.
Thanks for the clarifications, Bob! @Bentham’s Bulldog, you may be interested in the 2 comments above from Bob.
In this case, I feel like it would also be reasonable to argue that the evidential situation with respect to comparing the individual welfare per animal-year (not probability of sentience) of different species is so sparse that one should just focus on increasing the welfare of vertebrates. At least from my perspective, any comparison of the welfare (not probability of sentience) of shrimps with that of humans involves “guesses stacked on guesses”.
In addition, I see the lack of robust evidence for the sentience of soil springtails, mites, and nematodes as a case for further research on their sentience (although I would be surprised if it updated me towards thinking their expected individual welfare per animal-year is much lower than suggested by “number of neurons”^”exponent”). At some point, there was not robust evidence for the sentience of BSF larvae.
In any case, I assume the points about the robustness of evidence do not apply to soil ants and termites.
This makes sense to me. I ranked Arthropoda 1st in the Donation Election on that basis. At the same time, I suspect the optimal spending on research on soil animals is not 0. I got no results for “ants”, “termites”, “springtails”, “mites”, or “nematodes” on WAI’s grantees page.
I wonder whether there are some calculations one could do to compare the cost-effectiveness of building capacity for research on soil animals via doing this directly, or indirectly through research on farmed invertebrates.
Thanks for sharing! I will have a look.
Strongly agree about “the evidential situation with respect to comparing the individual welfare per animal-year”! I’ve always taken the numbers from the MWP much less seriously than others. I see that work as one part of a large picture, depending heavily on other arguments.
And thank you for voting for Arthropoda!
Thanks for the comments, Mal and Bob! I strongly upvoted both.
Rethink Priorities (RP) works on many cause areas, but I agree funding their projects on invertebrate welfare is a good option assuming they are not being supported by unrestricted funds which could be moved to other projects. I asked them a question to understand this better yesterday.
I think the Animal Welfare Fund (AWF) is open to funding that. Neil Dullaghan, senior fund manager there, said the following.
A possibly naive question — does this mean:
Arthropoda needs $55k to remain at the same level of funding (inflation-adjusted) as 2025?
Or that Arthropoda needs $55k to fulfil its 2026 plan, which may involve an increase (or decrease) in funding?
Or is $55k the overall “room for more funding” in some other sense?
Arthropoda treasurer here—pretty much option 2. We are hoping to increase our expenditure next year to run an extra grants round, add a contractor to help manage some things (currently we’re almost entirely volunteer), add a bit to our strategic reserve (to carry us through donation fluctuations without needing to pause grant-making), and a few other small bits and pieces. A good chunk of this expansion can be covered by our reserves + some existing donor commitments, and 55k is about what’s left.
We have actually a much higher room for more funding in theory, up to several million to run a couple of targeted programs we have in mind. These activities would require hiring someone to run them as a program manager as well as a lot more in grants. But we’re not really expecting EA Forum readers to fill that gap unless they happen to run a large foundation :)
In the interest of clarity, I’ve updated the original post in response to @Hugh P’s helpful question.
Great post. Short & to the point with links to specific claims for those who want to understand more.
I found the linked Case for Insect Consciousness really compelling. This is the sort of mindset I want conducting this kind of research. Reading the honest skepticism combined with careful self examination greatly boosted my respect for the project. I’m keen to learn more.
Maybe I’m just unable to find this information, but it seems the website doesn’t give any information on what and who Antrhopoda actually is: No information on what kind of legal entity they are if any, no information on who works there or who is responsible for making grants. This wouldn’t make me comfortable at all to make donation.
Arthropoda is a 501(c)(3). As this thread indicates, Mal Graham and I run the organization. We keep a lean profile because many science funders keep a lean profile. I realize that it isn’t optimal for fundraising, but I think it’s normal enough from the perspective of our grantees. If you’d like to discuss further, happy to chat.
Thanks for the read. Will be tuning in to your talk on this at EAGxAmsterdam!
Thanks for the post, Bob!
Only half of farmed animals are arthropods? Among cattle, hens, broilers, and farmed black soldier fly (BSF) larvae, mealworms, finfishes, and shrimps, I calculate only 51.5 % (= 2.68*10^11/(5.20*10^11)) are arthropods (farmed BSF larvae, mealworms, or shrimps). In addition, I estimate the welfare of the aforementioned farmed arthropods is 11.4 % (= −2.02*10^9/(-1.77*10^10)) of that of the aforementioned farmed animals for my preferred way of comparing welfare across species (where individual welfare per animal-year is proportional to “number of neurons”^0.5).
I do not expect all farmed animals to be arthropods as a 1st approximation in the next few years, but it looks like their fraction will increase. My numbers above rely on Rethink Priorities’ (RP’s) estimate of 223 billion farmed finfishes alive at any time in 2022, 38.2 billion farmed BSF larvae and mealworms alive at any time in 2022, and 230 billion farmed shrimps alive at any time in 2020. However, for RP’s projections of 259 billion farmed finfishes, 417 billion farmed BSF larvae and mealworms, and 399 billion farmed shrimps alive at any time in 2033, there would be 36.0 billion (= (259 − 223)*10^9) more farmed finfishes, and 379 billion (= (417 − 38.2 + 399 − 230)*10^9) more farmed arthropods. So, holding the population of farmed vertebrates besides farmed finfishes constant, 69.2 % (= (2.68 + 3.79)*10^11/((5.20 + 3.79 + 0.360)*10^11)) of the farmed animals in 2033 would be arthropods.
Thanks, Vasco! Abraham’s post covers many more farmed insects than BSF and mealworms. (For instance, the lower end of his farmed cochineal estimate is 4.6T deaths annually.) When you include those other species, I think the “rounding error” claim becomes more plausible. (Sorry not to be clear in the post: I probably gave the impression that I was only thinking of the standard “insects as food and feed” species.)
I’m always skeptical of scientific studies weighing in on the question of animal sentience because it just isn’t a scientific question. It’s a philosophical one. You may find this passage from David Deutsch’s book The Beginning of Infinity illuminating (chapter 12):
I would echo Deutsch’s points re the “anxiety-like states that were moderated by anti-anxiety medications” and other examples you mention.
Thanks for your comment, Dennis. One worry here is that you might be holding work on animal minds to an impossible standard. Yes, no one has a way to detect qualia directly, but surely we can make some inferences across the species boundary. Minimally, it seems very plausible that Neanderthals were sentient—and they, of course, were not homo sapiens. What makes that so plausible? Well, all the usual evidence: behavioral similarities, neurophysiological similarities, the lack of a plausible evolutionary story about why sentience would only have emerged after Neanderthals, etc.
Admittedly, plausibility decreases as phylogenetic distance grows (though the rate of the change is up for debate). Still, our epistemic situation seems to differ in degree, not in kind, when we consider stags—and, I submit, stag beetles.
One way to appreciate the value of the evidence that you’re criticizing is to imagine it away. Suppose that Bateson and Bradshaw had not found “the measurable quantities denoted… by the words ‘stress’ and ‘agony’ (such as enzyme levels in the bloodstream).” Surely it would have been less reasonable to believe that stags suffer in those circumstances. But if it would have been less reasonable without that evidence, it can be more reasonable with it.
Hi Bob,
To me, the outcome of the experiment wouldn’t matter either way. I wouldn’t suddenly accept it if it corroborated my view. (At least I like to think I’d be too rational to do that.) The methodological issues of using science to sidestep a philosophical problem, and of assuming the conclusion, remain.
When it comes to Neanderthals, I’m no expert. But when it comes to present-day animals, I haven’t found many behavioral similarities between them and humans. On the contrary, having studied animals a bit, I repeatedly find them to behave utterly differently from humans. And on the rare occasions they do behave similarly, it’s whenever humans are not being critical but enacting automated routines, like when sleepwalking. That’s when humans are pretty comparable to animals.
I’ve documented extensive evidence of animals behaving as though they are not sentient but robotic. I also address the arguments from phylogenetic proximity and neurophysiological similarities here and here, respectively – along with all the other commonly raised objections and questions.
My current view is that animals lack a critical ability and that sentience stems from this ability alone. Following Deutsch, I believe this critical ability is a binary matter, not a matter of degrees. So an organism either has it or it doesn’t – a stag wouldn’t have more of it than a stag beetle. I don’t think either one has any of it. That said, with the right programming, both could be made sentient (though that would presumably be highly immoral).
The good news here is that, if I am right, maybe animal suffering is a non issue after all, which means a whole host of ethical problems just kinda… resolve on their own.
Yes: if you’re right! But that’s an awfully big bet. As you might expect, it isn’t one I’m prepared to make. And I’m not sure it’s one you should be prepared to make either, as your credence in this view would need to be extremely high to justify it.
In any case, thank you for the detailed reply. I have a much better understanding of our disagreement because of it.
We have different epistemologies. I don’t use credences or justifications for ideas. I hold my views about animals because I’m not aware of any criticisms I haven’t addressed. In other words, there are no rational reasons to drop those views. Until there are, I tentatively hold them to be true.
See also https://www.daviddeutsch.org.uk/2014/08/simple-refutation-of-the-bayesian-philosophy-of-science/
Let’s say you faced a situation where you could either (a) improve the welfare of 1 human, or (b) potentially improve (conditional on sentience), to the same extent as the human, the welfare of X animals which you currently believe are not sentient.
Does your epistemology imply that no matter how large X was, you would never choose (b) until you found a “rational reason to drop your views”? But you admit there is a possibility that you will find such a reason in the future, including the possibility that credences are a superior way of representing beliefs?
Yes to both questions (ignoring footnotes such as whether it’s one’s responsibility to improve anyone’s ‘welfare’ or what that even means, and whether epistemology is about beliefs or “representing” them and whatever that might mean – your questions are based on a rather math-y way of looking at things that I disagree with but am entertaining just to play devil’s advocate against my own views).
There’s also Pascal’s Wager.
The problem with Pascal’s Wager is that it ignores reversed scenarios that would offset it: e.g. there could as well be a god that would punish you for believing in God without having good evidence.
I don’t think this would be applicable to our scenario. Whether we choose to help the human or the animals, there will always be uncertainty about the (long-term) effects of our intervention, but the intervention would ideally be researched well enough for us to have confidence that its expected value is robustly positive.
There are many problems with Pascal’s Wager. The problem I was thinking of is that, by imagining the punishment for not believing in god to be arbitrarily severe, one can offset even the smallest ‘chance’ of his existence.
We could arbitrarily apply that ‘logic’ to anything. For example, I don’t think rocks can suffer. But maybe I’m wrong. Maybe there’s a ‘small chance’ they do suffer anytime I step on them. And I step on many rocks every day – so many that even the smallest chance would warrant more care.
Maybe video-game characters can suffer. I’m pretty sure they can’t, but I can’t be 100% sure. Many people play GTA every day. So much potential suffering! Maybe we should all stop playing GTA. Maybe the government should outlaw any game that has any amount of violence…
And so on.
Sure there is a small chance, but the question is: what can we do about it and will the opportunity cost be justifiable? And for the same reason that Pascal’s Wager fails, we can’t just arbitrarily say “doing this may reduce suffering” and think it justifies the action, since the reversal “doing this may increase suffering” plausibly offsets it.