Despite my criticisms/thoughts below, how has no organization (RP, ACE, AWF, etc.) hired @Vasco Grilo yet? He's published extremely detailed good quality stuff just in his spare time and with a little bit of guidance/directional thought, I think he would be a great addition to many, many organizations out there.
Thank you for this thought-provoking post. I deeply appreciate seeing attention given to non-charismatic and extremely neglected animals such as soil arthropods, and the willingness to invest serious time into exploring how we might help them. It’s rare and valuable work.
Most comments here focus on questions about the sentience of these small animals, the implications of your conclusions or the appropriateness of basing moral action on highly uncertain utilitarian calculations. I’d like to contribute from a different angle: your soil arthropod abundance estimates. This is the part I understand best, and where I think there may be relatively low-hanging fruit for improving the precision of your numbers. While I work in ecology, I’m not a soil specialist, so these are informed observations rather than definitive expert judgments.
- You note that "0.1 kg of chicken meat causes 2.87 animal-days more in directly affected animals, but 6.16 million animal-years fewer in soil nematodes, mites, and springtails for feed crops replacing temperate grasslands, savannas, and shrublands." I’d suggest also considering cropland replacing forest. In Europe, much former cropland has been abandoned as agriculture concentrated on more productive areas, and these lands often undergo natural succession toward forest. Reduced meat demand could plausibly accelerate this trend, leading to forest regrowth rather than grassland expansion. In tropical regions, the dynamics are less certain, but a significant share of meat production still comes from newly deforested land. To capture the true impact on soil arthropod communities, at least some fraction of cropland should be compared against forest densities, not only grassland or savanna.
- Your soil arthropod abundance estimates already account for regional and habitat variation, but they appear to treat pasture as a single global category. I’d expect large differences between, say, nutrient-poor Brazilian pastures and nutrient-rich Siberian steppe pastures. It seems unlikely that these support similar densities of nematodes, mites, and springtails. Regional differentiation here might significantly change the results.
- Using your numbers, pasture densities come out much lower than cropland densities, which is counterintuitive. Cropland is usually subject to tillage (which can kill many surface-dwelling nematodes) and often receives substantial insecticide applications that likely harm a broad range of soil arthropods. In contrast, pasture arthropods are primarily exposed to antiparasitics like ivermectin. While most antiparasitics take time to degrade and are likely toxic to some coprophagous invertebrates, their total mass applied per hectare and their spatial footprint (concentrated in dung pats) are far smaller than the mass and coverage of insecticides on cropland. To me, this suggests that soil arthropod densities in pastures should be higher than those in croplands within the same biogeographic region, at least outside intensively treated livestock systems.
- Most arthropod density studies in temperate and subarctic regions sample in summer, when abundance and richness peak. Winter densities can be orders of magnitude lower, especially in subarctic soils. Extrapolating summer values to the full year may overstate average densities, so a season-weighted metric could be more accurate. In tropical systems, I’d expect most sampling to occur in the wet season, when densities are also highest. Adjusting for these seasonal biases would make your cross-system comparisons more robust.
- In your product comparisons, you account for the land area needed per kilogram of product. But did you also account for the split between cropland and pasture for each product in each region? Beef and mutton in tropical rangelands or the Asian steppe, for example, are often produced primarily from pasture rather than cropland. This proportion matters if the two land uses have very different soil arthropod densities.
Overall, I suspect these factors (land-use change baselines, regional pasture differences, cropland vs. pasture toxicity profiles, seasonal sampling biases and land-use composition by product) could shift some of your estimates by an order of magnitude or more. If we want to translate your insights into actionable guidance for career choices, donations or consumption patterns, resolving these uncertainties and producing estimates specific to each product and biogeographic region would make the conclusions much stronger.
Thanks again for opening this conversation, and for taking seriously the welfare of animals most people overlook!
Thanks for the great points, David! I strongly upvoted your comment.
I presented results for cropland replacing replacing temperate grasslands, savannas, and shrublands, but I consider many other replacements in my sheet. I estimate tropical and subtropical forests have 1.76 (= 5.25*10^6/(2.99*10^6)) times as many soil nematodes, mites, and springtails per m2 as tropical and subtropical grasslands, savannas, and shrublands, and that temperate forests have 1.42 (= 8.92*10^6/(6.30*10^6)) times as many soil nematodes, mites, and springtails per m2 as temperate grasslands, savannas, and shrublands. These ratios are higher than 1, so I think replacements of cropland with forests would tend to decrease soil-animal-years more than suggested by the results I presented in my post. This would strengthen my point that effects on soil animals are much larger than those on directly affected animals. However, I very much agree with your broader point that one should consider a mix of cropland and pasture replacing a mix of biomes (instead of just cropland replacing a single biome, as I did).
I also agree that regional and seasonal differences should be taken into account. Table S4 of Rosenberg et al. (2023) has not only the mean densities I used for each biome, but also 95 % confidence intervals (CIs), and the number of sites regarding each estimate. Acari are mites, collembola are springtails, formicidae are ants, and isoptera are termites.
Overall, I am still thinking that increasing agricultural-land-years is a good heuristic to decrease soil-animal-years. However, I am only confident that the effects on soil animals are larger than those on farmed animals. It would be great to have way more research decreasing the uncertainty about the effects on soil animals, not only about their welfare per animal-year, but also about the changes in their animal-years.
However, I very much agree with your broader point that one should consider a mix of cropland and pasture replacing a mix of biomes (instead of just cropland replacing a single biome, as I did).
I have just published a post where I consider this.
(Not really an argument, although I do disagree with stuff like RP's moral weights. Just kind of an impression / thought, that I am addressing to Vasco but also to invertebrate-suffering folks more broadly.)
Reading through this interesting and provocative (though also IMO incorrect) post and some of your helpfully linked resources & further analysis, it's hard to wrap my mind around the worldview that must follow, once you believe that each random 1m^2 patch of boreal taiga, temperate grassland, and other assorted forest biomes (as you tabulate here; screenshot below), despite appearing to be an inert patch of dirt topped by a few shrubs or a tree, actually contains the moral equivalent of DOZENS of suffering humans (like 20 - 40 humans suffering 24/7 per cube of dirt)??
In this Brian-Tomasik style world, humans (and indeed, essentially every visible thing) are just a tiny, thin crust of intelligence and complexity existing atop a vast hellish ocean of immense (albeit simple/repetitive) suffering. (Or, if the people complaining that nematode lives might be net-positive are correct but all the other views on the importance of invertebrates are kept the same, then everything we see is the same irrelevant crust but now sitting atop a vast incomprehensible bulk of primordial pleasure.)
What is the best way to imagine this? I am guessing that insect-welfare advocates would object to my image of each cube of dirt containing dozens of suffering humans, saying stuff like:
"you can't actually use RP-style moral weights to compare things in that way" (but they seem to make exactly these comparisons all the time?)
"it's an equivalent amount of suffering, yes, but it's such a different TYPE of suffering that you shouldn't picture suffering humans, instead it would be more accurate to picture X" (what should X be? maybe something simpler than an adult human but still relatable, like crying newborns or a writhing, injured insect?)
"negative QALYs aren't actually very bad; it's more like having a stubbed toe 24/7 than being tortured 24/7" (I am very confused about the idea of negative QALYs, neutral points, etc, and it seems everyone else is too)
Here is a picture of some square meters of boreal tundra that I googled, if it helps:
I'd also be very curious to know what people make of the fact that at least the most famous nematode species has only 302 neurons that are always wired up in the exact same way. Philosophically, I tend to be of the opinion that if you made a computer simulation of a human brain experiencing torture, it would be very bad to run that simulation. But if you then ran the EXACT same simulation again, this would not be 2x as bad -- it might not be even any worse at all than running it once. (Ditto for running 2 copies of the simulation on 2 identical computers sitting next to each other. Or running the simulation on a single computer with double-width wires.) How many of those 302 neurons can possibly be involved in nematode suffering? Maybe, idk, 10 of them? How many states can those ten neurons have? How many of those states are negative vs positive? You see what I'm getting at -- how long before adding more nematodes doesn't carry any additional moral weight (under the view I outlined above), because it starts just being "literally the exact same nematode experience" simply duplicated many times?
Anyways, perhaps this perspective --wherein human civilization is essentially irrelevant except insofar as we can take action that affects the infinite ocean of primitive-but-vast nematode experience -- would seem more normal to me if I came from a more buddhist / hindu / jain culture instead of a mostly christian/western one -- mahayana buddhism is always on about innumerable worlds filled with countless beings, things persisting for endless repetitions of lifetimes, and so forth. In contrast to christianity which places a lot of emphasis on individual human agency and the drama of historical events (like the roman empire, etc). Or one could view it as a kind of moral equivalent of the copernican / broader scientific revolution, when people were shocked to realize that the earth is actually a tiny part of an incomprehensibly vast galaxy. The galaxy is physically large, but it is mostly just rocks and gas, so (we console ourselves) it is not "morally large"; we are still at the center of the "moral universe". But for many strong believers in animal welfare as a cause area, and doubly or triply so for believers in insect welfare, this is not the case.
Agreed with Marcus Abramovitch that (if nematode lives are indeed net-negative, and if one agrees with RP-style weights on the importance of very simple animals), I think it WOULD strongly suggest (both emotionally and logically) pursuing "charities that just start wildfires" (which IMO would be cost-effective -- seems pretty cheap to set stuff on fire...), or charities that promote various kinds of existential risk. Vasco comments that nuclear war or bioweapons would likely result in even more insect suffering by diminishing the scope of human civilization, which makes a lot of sense to me. But there are other existential risks where this defense wouldn't work. Deliberately hastening global warming (perhaps by building a CFC-emissions factory on the sly) might shift biomes in a favorable way for the nematodes. Steering an asteroid into the earth, or hastening the arrival of a catastrophically misaligned AI superintelligence, might effectively sterilize the planet where nukes can't. And so on. All the standard longtermist arguments would then apply -- even raising the chance of sterilizing the earth by a little bit would be worth a lot. From my perspective (as someone who disagrees with the premises of this insect-welfare stuff), these implications do seem socially dangerous.
(Pictured: how I imagine it must feel to be an insect-welfare advocate who believes that every couple meters of boreal taiga contains lifetimes of suffering??)
Not really an argument, although I do disagree with stuff like RP's moral weights.
I liked your comment. At the same time, I would not dismiss the conclusions just because they are counterintuitive. I only see this as a reason for further investigation. I would be curious to know about your best guess for the welfare range of nematodes. I estimated the annual welfare of soil nematodes is -296 k times that of humans, so the welfare range of nematodes would have to be less than 3.38*10^-6 (= 1/(296*10^3)) times my estimate of 6.47*10^-6, 2.19*10^-11 (= 3.38*10^-6*6.47*10^-6), for my estimate of the absolute value of the welfare of nematodes to be smaller than that of humans.
"you can't actually use RP-style moral weights to compare things in that way"
"it's an equivalent amount of suffering, yes, but it's such a different TYPE of suffering that you shouldn't picture suffering humans, instead it would be more accurate to picture X" (what should X be? maybe something simpler than an adult human but still relatable, like crying newborns or a writhing, injured insect?)
[...]
Philosophically, I tend to be of the opinion that if you made a computer simulation of a human brain experiencing torture, it would be very bad to run that simulation. But if you then ran the EXACT same simulation again, this would not be 2x as bad -- it might not be even any worse at all than running it once.
I think what matters is the intensity and duration of the pain, not its uniqueness. I believe 2 h of pain of a given intensity is exactly 2 times as bad as 1 h of pain of the same intensity, regardless of the specific content of the painful experiences. Intuitively, I do not see how the badness of my pain can depend on the extent to which there is a similar pain being experienced somewhere in the multiverse.
"negative QALYs aren't actually very bad; it's more like having a stubbed toe 24/7 than being tortured 24/7" (I am very confused about the idea of negative QALYs, neutral points, etc, and it seems everyone else is too)
In my post, -1 QALY is the welfare needed to neutralise 1 QALY.
I'd also be very curious to know what people make of the fact that at least the most famous nematode species has only 302 neurons that are always wired up in the exact same way.
It looks like there are around 1 M species of nematodes, 148 (= 1*10^6/(6.74*10^3)) times as many as the 6.74 k species of mammals.
Nematode species can be difficult to distinguish from one another. Consequently, estimates of the number of nematode species are uncertain. A 2013 survey of animal biodiversity suggested there are over 25,000.[4][5] Estimates of the total number of extant species are subject to even greater variation. A widely referenced 1993 article estimated there might be over a million species of nematode.[6] A subsequent publication challenged this claim, estimating the figure to be at least 40,000 species.[7] Although the highest estimates (up to 100 million species) have since been deprecated, estimates supported by rarefaction curves,[8][9] together with the use of DNA barcoding[10] and the increasing acknowledgment of widespread cryptic species among nematodes,[11] have placed the figure closer to one million species.[12]
Anyways, perhaps this perspective --wherein human civilization is essentially irrelevant except insofar as we can take action that affects the infinite ocean of primitive-but-vast nematode experience -- would seem more normal to me if I came from a more buddhist / hindu / jain culture instead of a mostly christian/western one -- mahayana buddhism is always on about innumerable worlds filled with countless beings, things persisting for endless repetitions of lifetimes, and so forth. In contrast to christianity which places a lot of emphasis on individual human agency and the drama of historical events (like the roman empire, etc). Or one could view it as a kind of moral equivalent of the copernican / broader scientific revolution, when people were shocked to realize that the earth is actually a tiny part of an incomprehensibly vast galaxy. The galaxy is physically large, but it is mostly just rocks and gas, so (we console ourselves) it is not "morally large"; we are still at the center of the "moral universe". But for many strong believers in animal welfare as a cause area, and doubly or triply so for believers in insect welfare, this is not the case.
Great perspectives! Maybe a video about them could be interesting ;).
Agreed with Marcus Abramovitch that (if nematode lives are indeed net-negative, and if one agrees with RP-style weights on the importance of very simple animals), I think it WOULD strongly suggest (both emotionally and logically) pursuing "charities that just start wildfires" (which IMO would be cost-effective -- seems pretty cheap to set stuff on fire...)
I would be open to donating to such charities in principle. I do not shy away from counterintuitive conclusions. However, I am just very sceptical they would be cost-effective, or even just beneficial instead of harmful. Their scale would necessarily be limited due to the illegal nature of their work, which means supporting them would also likely be illegal, and therefore have to be super cost-effective to outweigh the expected decrease in future donations linked to the risk of fines, and being arrested, and outweigh the expected decrease in direct impact linked to the risk reputational damage worsening one's career. I also do not know whether fires decrease the number of nematodes. I guess they do nearterm, because I think 90 % of nematodes are in the top 15 cm of soil, and I assume this would still heat up sufficiently to kill the nematodes. However, the fire might increase the number of nematodes longer term.
Deliberately hastening global warming (perhaps by building a CFC-emissions factory on the sly) might shift biomes in a favorable way for the nematodes. Steering an asteroid into the earth, or hastening the arrival of a catastrophically misaligned AI superintelligence, might effectively sterilize the planet where nukes can't. And so on.
I think my point that increasing the risk of catastrophes increases animal-years also holds for the catastrophes above. It is way way harder to end life on Earth than to cause human extinction, and this is way way harder than just marginally decreasing human population. So I believe increasing the risk of large catastrophes would overwhelmingly decrease human-years, thus decreasing cropland, and increasing animal-years, while only infinitesimaly increasing the probability o extinction of all life on Earth.
All the standard longtermist arguments would then apply -- even raising the chance of sterilizing the earth by a little bit would be worth a lot. From my perspective (as someone who disagrees with the premises of this insect-welfare stuff), these implications do seem socially dangerous.
I do not think reducing the nearterm risk of human extinction is astronomically cost-effective. Likewise, I do not think increasing the risk of extinction of all life on Earth is astronomically cost-effective. In addition, I believe the best ways of increasing the risk of extinction of all life on Earth involve a peaceful gradual expansion of the activities of humans and their eventual non-biological descendents.
Love your integrity @Vasco Grilo🔸. Comments like this show that you really put your money and lifestyle where you mouth is (or your mouth where your math is!), even when it seems strange at times to simpler folks like myself.
"My whole-food plant-based diet is cheaper than a standard diet, so it allows me to donate more, and I think the increased impact from this is larger than the harm caused by eating more plant-based foods."
I'm supportive of doing this kind of thinking, but I think taking your beliefs to their logical conclusion suggests we should be looking to found charities that will end all life on earth; nuclear PROLIFERATION charities, perhaps charities that seek to make and release bioweapons that will kill of small animals, insects, etc. and maybe just charities that start wildfires. Have you given much thought to this?
Also, why does everyone assume that small organisms necessarily live net negative lives?
One should think at the margin. Starting organisations working on extreme life extension does not have to be the best way to increase human-years. I think GiveWell's top charities increase human-years more cost-effectively than the vast majority of work on aging. Likewise, increasing the chance of all soil nematodes, mites, and springtails dying through increasing the risk of nuclear war or pandemics does not have to be among the best ways to decrease their animal-years. In fact, I believe they are super bad ways of doing it. I think they would decrease human-years due to increasing the expected annual deaths from nuclear war and pandemics, thus decreasing future food production, and cropland-years, and therefore increasing the animal-years of soil nematodes, mites, and springtails. Even if increasing the risk of nuclear war and pandemics decreased the animal-years of these, I predict the cost-effectiveness respecting an increase in the probability of extinction would be astronomically low. I got a nearterm annual risk of human extinction from nuclear war of 5.93*10^-12, and I guess the probability of all soil nematodes, mites, and springtails dying would be orders of magnitude lower.
I am sceptical that illegal activities like starting wild fires would be cost-effective. I would be open to donating to charities pursuing these in principle. I do not shy away from counterintuitive conclusions. However, I am just very sceptical they would be cost-effective, or even just beneficial instead of harmful. Their scale would necessarily be limited due to the illegal nature of their work, which means supporting them would also likely be illegal, and therefore have to be super cost-effective to outweigh the expected decrease in future donations linked to the risk of fines, and being arrested, and outweigh the expected decrease in direct impact linked to the risk reputational damage worsening one's career.
I am very uncertain about whether soil nematodes, mites, and springtails have positive or negative lives. I calculated soil nematodes, mites, and springtails have negative lives with a probability of 58.7 %, 55.8 %, and 55.0 %. Note at least some of nematodes' deaths seem to be quite painful[1]. From Félix and Braendle (2010):
C. elegans shares its natural environment with a diverse animal community, in particular arthropods, molluscs and other nematodes, some of which also feed on microbes proliferating upon plant decomposition. Many are potential dispersal vectors as well as predators of C. elegans. Frequently co-occurring predators include fungi, which, depending on the species, invade the nematode through spores attaching to the cuticle or the intestine, or use trapping devices that immobilize the animal and perforate it (Figure 2). Nematophagous mites, springtails and nematodes are other potential predators often encountered in the C. elegans habitat.
The broader nematode community associated with C. elegans comprises microbivorous nematodes, often including other rhabditid nematodes, such as Oscheius sp., diplogastrids or panagrolaims, which likely compete with C. elegans for microbial food resources. Also found in rotting fruits are fungal-eating and predatory nematodes. Sometimes, C. elegans co-occurs with other Caenorhabditis species in the same location or even in the same few square millimetres of substrate. Given the rapid proliferation upon food availability, intraspecific competition for food is probably substantial.
C. elegans also constantly interacts with a variety of obligate and non-obligate parasites, such as fungi, microsporidia, bacteria and viruses (Troemel et al., 2008; Félix et al., 2011; Félix and Duveau, 2012; Hodgkin et al., 2013) (Table 1). These parasites infect their host via the two most exposed parts of the nematode, the cuticle and the intestine. Some non-invasive bacteria form a biofilm along the nematode's cuticle or directly stick to it (Hodgkin et al., 2013). Other bacteria proliferate in the nematode gut, which may induce constipation and likely impairs nutrient uptake (Félix and Duveau, 2012). The most intrusive parasites enter and proliferate inside the nematode body. Some pierce the cuticle (e.g., Drechmeria coniospora [Couillault et al., 2004], Figure 2J), while others enter intestinal cells via the apical membrane (e.g., microsporidia and Orsay virus [Troemel et al., 2008; Félix et al., 2011]).
I am focussing on nematodes because I calculated the increase in the welfare of soil nematodes from increasing cropland to range from 90.5 % to 94.3 % of the increase in the welfare of soil nematodes, mites, and springtails, depending on the original biome.
I suppose I'm saying that I think your beliefs suggest we should try to annihilate the world or try to extinguish all life.
I think hidden in a lot of your analysis is one of the following
Negative utilitarianism. I think this is a fine belief to hold but I think it should be stated outright.
An assumption that the lives of many/most/all animals is net negative by default and we need evidence that they are positive for them not to be considered net negative.
I think 2 is more likely but I think a lot of the people that think along your lines (maybe someone like Bentham's Bulldog too), seem to assume that life is likely to be negative and I just don't see why this assumption should be expected. We don't really see any animals committing suicide, they clearly show desire/preference to live (they try to escape death at many costs), a lot of life for humans who we consider to usually be net positive is spent on things where we "struggle" to maintain existence and yet most people are fairly happy with their life.
I also agree that we should be highly uncertain about whether soil creatures live positive or negative lives but your analysis more or less assumes that the sign is negative and everything else follows from there.
On death, most of the life of a creature is usually not spent during it's death. I'm happy for interventions for farmed animals to reduce pain during death (and humans too!) but I think basing a lot of calculations on this doesn't capture most of the animal's life.
Last, I think your analysis ignores something I consider to be extremely important and in fact, the main reason I'm (and I think others should be) vegan. Namely, a ~daily reminder that animals matter and a reduction in cognitive dissonance and the effect it has on others. I think my (and any other) individual diet's direct harm is uncertain, has a lot of crucial considerations, etc. but, I think a lot of rationalists like to pretend they are above usual human thoughts/instincts on this matter. I discuss this more here.
I fully endorse expectational total hedonistic utilitarianism. I strongly believe there are many experiences that are better than nothing. Negative utilitarianism implies that the painless elimination of all experiences forever would be as good as utopian lives for all beings forever. So negative utilitarianism makes no sense to me.
As I said in my comment above, I am very uncertain about whether soil nematodes, mites, and springtails have positive or negative. However, I would not see the absence of suicide among these animals as compelling evidence that they have positive lives. I estimated 6.37 % of humans have negative lives, but only 0.00946 % commited suicide in 2021, 0.149 % (= 9.46*10^-5/0.0637) as many as those I estimate to have negative lives.
I would get more counterintuitive conclusions if I assumed soil nematodes, mites, and springtails have positive lives (although this is not a reason for me to assume their lives are negative). Generally improving human lives, and the conditions of farmed animals would then harm soil animals much more than it benefits humans and farmed animals.
@Marcus Abramovitch 🔸, I am tagging you because I forgot to reply to the last paragraph of your comment. I do not think it makes senses to remind myself and others to help animals by doing something that I believe actually harms animals. However, I still eat fully plant-based because I think the benefits from increased donations are greater than the harm caused to animals due to less agricultural-land-years.
Your model treats microbial interactions as universally negative. Yet the scientific literature shows nematodes host beneficial symbionts that aid growth and immunity. By omitting these, this model is incomplete—and biased toward suffering. Even slight adjustments to the qualia of rest or seeking behavior would skew the outcome.
I have not covered any microbes. Are you suggesting that increasing cropland, thus decreasing the number of soil ematodes, is harmful because it decreases the number of microbes? I would agree that increasing cropland decreases the number of microbes, and I would not be surprised if the effects on microbes were much larger than those on soil nematodes, mites, and springtails. From Table S1 of Bar-on et al. (2018), there are 10^30 terrestrial deep subsurface bacteria, 10^9 (= 10^(30 - 21)) times as many as nematodes, and I guess the welfare range of bacteria can seasily be much larger than 10^-9 that of nematodes. However, the number of bacteria per unit area is correlated with the number of soil nematodes, mites, and springtails per unit area, as both are driven by net primary production (NPP), and I speculate bacteria have negative lives. So I believe my conclusion that increasing cropland is beneficial would hold accounting for bacteria.
I only skimmed the post, but I want to say that it seems good to write posts like this, and I am surprised and slightly disheartened by the limited engagement you have gotten here and in various comments. These seem like very important topics, thanks for working on them!
@Vasco Grilo🔸 I have to admire your commitment to pursusing this kind of reasoning to wherever that leads. The evolution of your views on charity effectiveness over time has been fascinating, and I'm interested to see where it goes next as well.
I'm not sure if I've actually asked you this in a comment before, apologies if I have, but what is your reply to the Pascal mugger problem?
If I say to you:
"I am a sorceror from another dimension, who has the power to conjure arbitrary numbers of sentient beings at will. How likely do you think this claim is?"
Then whatever you reply, I say: "Give me your wallet, or I will threaten to torture/'give joy to' 10x the reciprocal of that probability estimate"... What do you say to this?
I feel like everyone just has a different threshold to what they feel is being Mugged by the main man Pascal. I think @Vasco Grilo🔸 just has a higher threshold than others - judging by comments like this "I would say a 10^-100 chance of 10^100 QALY is exactly as good as a 100 % chance of 1 QALY"
On that note I do wonder if I showed up at Vascos house and said "I am from the future, if you give me 20,000 dollars now I will reduce all animal suffering in the future by 50%" whether he'd hand me the cash on the off chance.... :D.
Might do a poll on this sometime asking peoples "Mugging thresholds", but I would need different orders of magnitude of probabilities on the poll (not just agree/disagree) so its probably ont possible at the moment...
On that note I do wonder if I showed up at Vascos house and said "I am from the future, if you give me 20,000 dollars now I will reduce all animal suffering in the future by 50%" whether he'd hand me the cash on the off chance.... :D.
This was funny. I would not hand you 20 k$. I would guess the probability of you decreasing future suffering by 50 % to be infinitesimal, although I would ask a few questions to make sure. However, I would be happy to buy you a dinner!
One should be scope-sensitive not only to astronomically large benefits, but also astronomically small probabilities. I would say a 10^-100 chance of 10^100 QALY is exactly as good as a 100 % chance of 1 QALY. However, I think the expected benefits coming from astronomically large benefits will be negligible for reasonable distributions describing the benefits. For example, if the benefits are described by a power law distribution with tail index alpha > 0, their probability will be proportional to "benefits"^-(1 + alpha), so the expected benefits linked to a given amount of benefits will be proportional to "benefits"*"benefits"^-(1 + alpha) = "benefits"^-alpha. This decreases with benefits, so the expected benefits coming from astronomically large benefits will be negligible.
Longtermists typically come up with huge amounts of benefits (e.g. 10^50 QALY), and then independently guess a probability which is only moderately small (e.g. 10^-10), which results in huge expected benefits (e.g. 10^40 QALY). Yet, the amount of benefits is not independent from their probability. In contrast, my estimates of the effects on soil nematodes, mites, and springtails are based on empirical evidence, although they are of course still very uncertain.
Thanks for the reply, I appreciate the distinction you're drawing between your arguments and strong longtermism, but I don't think that directly addressed my question?
In the version of the thought experiment I described, the mugger is claiming magical powers which would enable them to create arbitrarily many lives of arbitrary welfare. Unless you assign this claim a probability of literally zero, then you are vulnerable to mugging, because they can then adjust their threat to match your estimate.
I think about the expected benefits linked to an improving offer from the mugger as the benefits of increasing the chance of astronomically valuable futures. If the mugger improved the offer from 1 to 10^10 QALY, I would expect the benefits to become less than 10^-10 as likely to be instantiated, such that the expected benefits linked to an offer of 1 QALY would actually be larger. In agreement with this, in real life, I am more worried about someone asking me on the street for 100 $ than for 100 T$ (close to the gross world product). I expect the probability of losing 100 T$ to be way less than 10^-12 of the probability of losing 100 $.
The probability of arbitrarily large benefits does not have to be literally 0. The benefits can be arbitrarily large if they are described by a power law distribution, but I illustrated in my comment above the expected benefits linked to a given amount of benefits decrease to 0 as the amoung of benefits increases.
I would guess the probability is, for example, p(N) = 10^-N, which would imply the expected benefits approaching 0 as N increases (because the limit of N*10^-N is 0). I do not have a strong view about the specific function p(N) representing the probability, but I think reality is such that p(N)*N tends to 0 as N increases.
Might be missing something silly, but I think you're still dodging the question. There is no specific N in the claim I gave you. This magician is claiming that they have a spell that given any N, will create N beings.
So are you just saying you assign that claim zero probability?
"I am a sorceror from another dimension, who has the power to conjure arbitrary numbers of sentient beings at will. How likely do you think this claim is?"
I would reply by saying the likelihood of that is arbitrarily close to 0, although not exactly 0, and noting the number of sentient beings to be created times the likelihood of them actually having the ability to create them tends to 0 as the number of sentient beings tends to infinity.
I would reply by saying the likelihood of that is arbitrarily close to 0, although not exactly 0
I believe this is mathematically impossible! But probably not worth going back and forth on this.
I actually basically agree with your response to the Pascal mugger problem here. I'm still very uncertain, but I think I would endorse:
Making decisions by maximizing expected value, even when dealing with tiny objective probabilities.
Assigning lower prior probability to claims in proportion to the size of impact they claim I can have, to avoid decision paralysis when considering situations involving potential enormous value.
Assigning a probability of literally zero to any claim that says I can influence arbitrarily high amounts of value, or infinite amounts of value, at least for the purposes of making decisions (but drawing a distinction between a claim having zero subjective 'probability' and a claim being impossible).
But I think this approach makes me sceptical of the argument you are making here as well. You claim your argument is different to longtermism because it is based on empirical evidence (which I take it you're saying should be enough to override our prior scepticism of claims involving enormous value?), but I don't fully understand what you mean by that. To me, an estimate of the likelihood of humanity colonizing the galaxy (which is all strong longtermism is based on) seems as robust, if not more robust, than an estimate of the welfare range of a nematode.
For instance, I don't even know how you define units of welfare in a way that lets you make comparisons between a human and a nematode, let alone how you would go about measuring it empirically. I suspect it is likely impossible to define in a non-arbitrary way.
You claim your argument is different to longtermism because it is based on empirical evidence (which I take it you're saying should be enough to override our prior scepticism of claims involving enormous value?), but I don't fully understand what you mean by that. To me, an estimate of the likelihood of humanity colonizing the galaxy (which is all strong longtermism is based on) seems as robust, if not more robust, than an estimate of the welfare range of a nematode.
What is relevant for longtermist impact assessments is the increase in the probability of achieving astronomical welfare, which Iguess is astronomically lower than the original probability of this. For all the longtermist impact assessments I am aware of, such increase is always a purely subjective guess. My estimate of the welfare range of nematodes of 6.47*10^-6 is not a pure subjective guess. I derived it from RP's mainline welfare ranges, which result from some pure subjective guesses, but also empirical evidence about the properties of the animals they assessed. The animal-years of soil animals affected per $ are also largely based on empirical evidence.
Combining some empirical evidence with a subjective guess does not necessarily make the conclusion more robust if the subjective guess is on shaky ground. An argument may only be as strong as its weakest link.
I would not expect the subjective judgements involved in RP's welfare range estimates to be more robust than the subjective judgements involved in estimating the probability of an astronomically large future (or of the probability of extinction in the next 100 years).
I definitely agree that the subjetive guesses related to RP's mainline welfare ranges are on shaky ground. However, I feel like they are justifiably on shaky ground. For example, RP used 9 models to determine their mainline welfare ranges, giving the same weight to each of them. I have no idea if this makes sense, but I find it hard to imagine which empirical evidence would inform the weights in a principled way.
In contrast, there is reasonable empirical evidence that effects of interventions decay over time. I guess quickly enough for the effects after 100 years to account for less than 10 % of the overall effect, which makes me doubt astronomical longterm impacts.
I would also say there is reasonable evidence that the risk of human extinction is very low. A random mammal species lasts 1 M years, which implies an annual extinction risk of 10^-6. Mammals have gone extinct due to gradual or abrupt climate change, or other species, and I think these sources of risk are much less likely to drive humans extinct. So I conclude the annual risk of human extinction is lower than 10^-6. I guess the risk 1 % as high, 10^-7 (= 10^(-6 - 2 + 1)) over the next 10 years. I do not think AI can be interpreted as other species because humans have lots of control over its evolution.
Thanks Vasco for writing this post and being open minded to evolve viewpoints - much appreciated.
Do you have thoughts on whether long term it would be preferable for net suffering to have more cropland with higher amount of nematodes per sq/m etc supporting a given population size with current per capita animal consumption levels, vs relatively more consumption of land efficient alternatives to animal products, enabling higher human population and greater amount of urban/suburban land ie - with less nematodes per sq/m.
I am confident increasing the consumption of at least beef increases agricultural land, thus decreasing the animal-years of soil nematodes, mites, and springtails, despite decreasing the human population due to being less healthy. Eating 85 g of red meat is associated with losing 1 microlife, 30 min. I speculate the causal effect is 1/3 as large, which implies eating 100 g of beef shortens one's life by 11.8 min (= 30*1/3*100/85), 2.24*10^-5 year (= 11.8/60/24/365.25). For the global agricultural land per capita in 2022 of 0.60 ha, that implies a decrease in agricultural land of 0.134 m2-year (= 2.24*10^-5*0.60*10^4), or 1.34 m2-year/beef-kg (= 0.134*1/0.1). The urban land per capita in 2015 was 257 m2-year (= 1.91*10^12/(7.44*10^9)), so the decrease in urban land would be 0.00576 m2-year (= 2.24*10^-5*257), or 0.0576 m2-year/beef-kg (= 0.00576*1/0.1), only 4.30 % (= 0.0576/1.34) of the decrease in agricultural land, and therefore negligible. The decrease in agricultural land due to decreasing the human population is only 0.411 % (= 1.34/326) of the increase in it needed to consume the beef. So increasing the consumption of beef increases agricultural land.
Thank you for this interesting, weird, surprising, and important post. It is a mind f*ck.
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Question: You say, "In particular, it is crucial to know whether [soil nematodes, mites, and springtails] have positive or negative lives."
Is another crucial question to find out whether soil nematodes, mites, and springtails are sentient at all?
To me, reading this, the main emotional / System 1 reaction I had was, "But those animals are SO small and SO different from me. I can't even see them! It's hard for me to believe they're sentient." I looked briefly on the EA Forum and found this: https://forum.effectivealtruism.org/posts/jYdmcrgAj5odTunCT/demodex-mites-large-and-neglected-group-of-wild-animals ("Strictly speaking, it's unclear whether Demodex mites are sentient. But this is mostly because nobody has researched this question - for many groups of invertebrates where people have looked (e.g. insect groups), the science does support these groups being sentient. To me, it seems plausible enough that Demodex mites are sentient that we should be giving serious consideration to their interests.").
What is your opinion on how likely these small animals are to be sentient? E.g. do you think it's more like 10% likelihood or more like 90% likelihood?
To me "whether they have positive or negative lives" seems to imply that you think they likely do have lives with a valence one way or the other, as opposed to just unvalenced lives like we imagine plants and bacteria have. But maybe that's not what you meant.
I realize that there are SO many animals that even a small chance of them being conscious is a big important moral thing for us to consider. So to be clear I'm not trying to push back on caring about them even if the likelihood of them being conscious is only like 10%. I'm just curious what you think.
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Update: After posting this, I just googled to see what soil mites look like up close. And the pictures I found of them are SO CUTE. They just look like little bugs, with cute little legs and stuff. So that makes me change my System 1 reaction to a new System 1 reaction of "Oh, of course these little cuties are sentient." :-)
Thanks for the comment, Alene! I will focus on nematodes because I calculated the increase in the welfare of soil nematodes from increasing cropland to range from 90.5 % to 94.3 % of the increase in the welfare of soil nematodes, mites, and springtails, depending on the original biome.
I think decreasing the uncertainty about the probability of sentience of nematodes is less important than decreasing the uncertainty about whether they have positive or negative lives. I believe it would have to be unreasonably low for the effects on farmed animals to dominate. For example, I estimated eating chicken meat benefits soil animals 4.81 k times as much as it harms directly affected animals, so the effects on soil animals would have to become less than 0.0208 % (= 1/(4.81*10^3)) as large for the effects on directly affected animals to be larger. This could be achieved, for instance, if both the their probability of sentience, and welfare range given sentience became 1.44 % (= (2.08*10^-4)^0.5) as large. RP estimated a probability of sentience for nematodes of 6.8 %, 6.8 % that of humans of 100 %. As a result, for the effects of eating chicken meat on directly affected animals to be larger than those on soil animals, the probability of sentience of nematodes would have to drop by a factor 4.72 (= 0.068/0.0144) times as large as the factor linked to decrease in RP's probability of sentience from humans to nematodes.
I assume there is a probability of 93.2 % (= 1 - 0.068) of soil nematodes having practically negligible welfare based on RP's probability of sentience for nematodes of 6.8 %. However, whether they have positive or negative lives in expectation is determined by what happens given sentience.
RP's probability of sentience for nematodes of 6.8 % may seem low, but people take care to decrease way smaller risks. For example, travelling 370 km by car only increases one's risk of death by around 10^-6, but people still wear seat belts.
Got it. I think I understand what you're saying. I'm not as good with math so I'm not sure if I followed the calculations. But to try to put what you're saying in less mathy terms, I think you're basically saying:
1) There are WAY WAY WAY more nematodes than farmed animals.
2) Nematodes are significantly less likely to be sentient than farmed animals.
3) But the fact that there are WAY WAY WAY more nematodes than farmed animals still means that, from an expected value perspective, one would still expect the effect of farming on nematodes to be much bigger than the effect of farming on farmed animals.
Is that right?
Like, if you could enter a deal where a person is guaranteed to pay you $1 up front, but in exchange you accept a 6% chance that the person will later take $4,810,000 from you, it'd be a bad deal to make, even though the most likely outcome is you simply gain a dollar and don't pay anything. Is that a good analogy?
Yes, that is basically right[1]. For example, I estimate nematodes are 7.76 % (= 0.068/0.876) as likely to be sentient as chickens ("significantly less"), but that there are 16.7 billion (= 4.89*10^20/(29.2*10^9)) times as many soil nematodes as farmed chickens ("WAY WAY WAY more").
Yes, I think that analogy illustrates why I think broadly advocating for decreasing the consumption of animal-based foods tends to be harmful to animals.
With the caveat that what matters besides population is the welfare per animal-year, which is the product between the probability of sentience, welfare range given sentience, and welfare per animal-year as a fraction of the welfare range.
It is now unclear to me whether donating to HIPF from CEARCH is beneficial or harmful due to the possibility of their grants increasing food consumption.
I estimated buying beef, which I believe is the most cost-effective way of increasing animal welfare through diet, has a cost-effectiveness of 408 QALY/$, 3.14 % (= 408/(13.0*10^3)) of HIPF’s, for a cost of 6.32 $/meat-kg. Consequently, I infer buying food which is cheaper than this by more than 0.198 $/food-kg (= 0.0314*6.32), and donating the savings to HIPF increases animal welfare more. Legumes are generally cheaper than beef by much more than that.
I estimated buying beef has a cost-effectiveness of 37.8 % (= 408/(1.08*10^3)) of GiveWell's top charities, which had the highest cost-effectiveness besides HIPF's in my analysis. So I now infer buying food which is cheaper than beef at 6.32 $/meat-kg by more than 2.39 $/food-kg (= 0.378*6.32), and donating the savings to GiveWell's top charities increases animal welfare more. I feel like replacing beef with legumes is still worth it, but I am now much less confident.
It is now unclear to me whether donating to HIPF from CEARCH is beneficial or harmful due to the possibility of their grants increasing food consumption.
I have now estimated funding HIPF increases agricultural land 78.5 % as cost-effectively as I had calculated due to increasing calorie consumption. This is a minor change, so I maintain my recommendation of funding HIPF. I also confirmed that taxing beef decreases agricultural land. I estimated that consuming unprocessed red meat in the US increases agricultural land 1.72 k times as much as it decreases it from reducing life expectancy.
Hi Vasco! I’m reposting my reply to your comment in Lewis’s newsletter here given your (admirable) value of public discussion since this seems like the fitting spot to go back and forth about it:
I value your respect for large numbers and the breadth of your moral circle.
I just weigh the factors differently (putting a large premium on known suffering), and I put the likelihood of a net negative experience for soil animals and many wild animals in undisturbed habitats at 50% or less.
I care very much about the lives of wild animals, but I am skeptical that we know how to measure their subjective experience. For example, maybe nematodes experience pain often but find euphoric pleasure in burrowing through soil all day. Most wild animals experience fear often but maybe they find so much joy in being part of a family that the fear pales in comparison.
I come from a long line of humans whose amount of suffering was quantitatively much higher than their amount of pleasure, but the things that did bring pleasure (e.g., pursuit of meaning) made life feel worth living. A researcher wouldn’t know this through observation, especially because smiling and physical contact aren’t common in my culture (#soviets)
I’m not suggesting we can’t ever learn about the subjective experience of another species. Anyone who lives with chickens will easily identify chicken happiness. But we can only do this because we have lots of data (alongside some helpful similarities in the communication of our species).*
I do believe we’ll learn much more about wild animals through research. And even if we find out soil animals or others suffer constantly, I would likely still advocate for life improving** rather than life ending measures.
In part because I believe in the inherent dignity of any life and in part because we living beings are so deeply interconnected that it would be impossible to predict the unintended consequences of mercy killing large numbers of animals.
While I disagree with your conclusion, your approach has sparked lots of introspection for me, and I am eager to learn more about soil animals and our relationship to them, so thank you!
changes from my comment in the newsletter: *I clarified my perspective on measuring subjective experience, and **I changed the world “welfare” to “improving” since it seems your definition of welfare encompasses ending life, so my goal is to clarify the distinction I’m making. I also fixed a typo :) Otherwise the wording is the same.
Thanks for reposting the comment, and welcome to the EA Forum, Tania! For readers' reference, here is the thread in Lewis Bollard's newsletter. I have updated my last reply in the thread to include the below. The 1st paragraph is very similar to the initial version of my reply. The 2nd paragraph is new.
If soil animals had positive lives, instead of negative lives as I guess they do, I would want to decrease agricultural land to increase soil-animal-years, and therefore would tend to support increasing the consumption of plant-based foods, which tend to require less agricultural-land-years per food-kg than animal-based foods. However, in this case, I would become pessimistic about improving the conditions of farmed animals because this tends to increase agricultural land. Changing the sign of the welfare of soil animals from negative to positive in my cost-effectiveness analysis of cage-free and broiler welfare corporate campaigns, I would estimate these increase the net suffering of soil animals 1.15 k and 18.0 k times as much as they decrease the net suffering of chickens, thus being very harmful.
Hereis some context about the capacity for welfare, and suffering experienced by soil nematodes, which are the main driver of my estimated effects on soil animals.
I estimated buying beef, which I believe is the most cost-effective way of increasing animal welfare through diet
Eggs require 6.27 m2-year/egg-kg, and ones from cages in the European Union (EU) cost 2.98 $/egg-kg (= 2.55*1.17), so these eggs increase cropland by 2.10 m2-years per $ (= 6.27/2.98). I got 51.6 m2-year/$ for beef, 24.6 (= 51.6/2.10) times my estimate for eggs from cages in the EU.
Animal farming impacts soil nematodes, mites, and springtails hugely more than directly affected animals?
This is the third in a sequence of posts taken from my recent report: Why Did Environmentalism Become Partisan?
Summary
Rising partisanship did not make environmentalism more popular or politically effective. Instead, it saw flat or falling overall public opinion, fewer major legislative achievements, and fluctuating executive actions.
Public Opinion...
I think right now EAs might be making a significant mistake by paying insufficient attention to the political realm. As EAs we tend to figure out what’s most impactful for us to work on and focus hard. That’s great! But there are various actions that are ‘non-delegatable’ - the extent to which an individual can do the action is limited (like voting, going to a protest, making hard money contributions to particular campaigns). It might be useful if we were all more in the habit of doing variou...
This post presents the executive summary from Giving What We Can’s impact evaluation for 2025. At the end of this post we share links to more information, including the full report and...
Decreases the living time of (wild) soil nematodes, mites, and springtails hugely more than it increases that of directly affected animals.
Increases the welfare of soil nematodes, mites, and springtails hugely more than it changes that of directly affected animals.
My best guess isthat those soil animals have negative lives, so I think decreasing their animal-years by increasing land use is beneficial. I infer the following replacements are generally beneficial due to increasing land use:
Plant-based foods, farmed shrimp (prawns), eggs, or farmed fish with poultry or pig meat.
Poultry or pig meat with cheese.
Cheese with beef.
I believe broadly advocating for decreasing the consumption of animal-based foods tends to be harmful. I predict it decreases cropland due to predominantly resulting in the replacement of poultry and pig meat, and beef with plant-based foods. In agreement with this, I estimated School Plates in 2023, and Veganuary in 2024 harmed soil nematodes, mites, and springtails 5.42 k and 3.58 k times as much as they benefited directly affected animals.
I consider it very worth it to decrease the uncertainty about how interventions affect the living time of soil nematodes, mites, and springtails, and about their welfare in QALY/animal-year.
I have been eating fully plant-based for 6 years, and plan to continue. My whole-food plant-based diet is cheaper than a standard diet, so it allows me to donate more, and I think the increased impact from this is larger than the harm caused by eating more plant-based foods.
Impact of animal farming on the living time of animals
I estimate animal farming decreases the living time of soil nematodes, mites, and springtails animals hugely more than it increases that of directly affected animals. For example, I conclude 0.1 kg of chicken meat causes 2.87 animal-days more in directly affected animals, but 6.16 M animal-years less in soil nematodes, mites, and springtails for feed crops replacing temperate grasslands, savannas, and shrublands, which is 783 M times as many animal-years. For that land use change, among the 8 animal-based foods below, the decrease in the living time of soil nematodes, mites, and springtails ranges from 551 k (shrimp) to 436 billion (dairy milk) times the living time of directly affected animals.
I determined the decrease in animal-years in soil nematodes, mites, and springtails per food-kg multiplying the m2-years per food-kg fromPoore and Nemecek (2018) by estimates for the decrease in those animals per m2 due to expanding feed crops, which I computed from myestimates for the number of soil nematodes, mites, and springtails per m2. I set the density of soil mites, and springtails by biome to the values from Table S4 of Rosenberg et al. (2023), and got the density of nematodes from the product between the sum of the densities of mites and springtails, and 51.5, which is my estimate for the number of soil nematodes as a fraction of the number of soil mites and springtails. I underestimated the decrease in animal-years in soil animals due to assuming none of the land use regards the expansion of pastures, which I estimate have 41.7 % (= 1 - 734*10^3/(1.26*10^6)) less soil animals per unit area than crops.
I set the increase in animal-years in directly affected animals per food-kg of animal-based foods to estimatesfromFaunalytics for the United States (US) for the living time of farmed and wild animals, including farmed animals which die before slaughter, and 1 animal-day per wild feeder fish, which is supposed to be the time from catch to death.
Impact of animal farming on the welfare of animals
I estimate animal farming increases the welfare of soil nematodes, mites, and springtails hugely more than it changes that of directly affected animals. For example, I conclude 0.1 kg of chicken meat decreases the welfare of directly affected animals by 0.00593 QALYs, but increases that of soil nematodes, mites, and springtails by 28.5 QALYs for feed crops replacing temperate grasslands, savannas, and shrublands, which is 4.81 k times as many QALYs. For that land use change, among the 8 animal-based foods below, the increase in the welfare of soil nematodes, mites, and springtails ranges from 9.39 (shrimp) to 11.7 M (dairy milk) times the absolute value of the change in the welfare of directly affected animals.
Food
Decrease in the welfare of directly affected animals (QALY/food-kg)
Shrimp
7.38
Fish
0.0454
Chicken
0.0593
Eggs
0.0430
Turkey
0.0237
Beef
-0.00145
Pork
0.00716
Dairy milk
-1.78*10^-5
I determined the increase in the QALYs of soil nematodes, mites, and springtails per food-kg multiplying the aforementioned m2-years per food-kg by estimates for the increase in the QALYs of soil nematodes, mites, and springtails per m2 due to expanding feed crops, which I computed from myestimates for the QALYs of soil nematodes, mites, and springtails per m2. I got these multiplying the aforementioned densities of soil animals by a welfare of soil nematodes, mites, and springtails of -4.36*10^-6, -1.57*10^-5, and -2.35*10^-5 QALY/animal-year, which I calculated for welfare ranges equal to 0.324 %, 1.79 %, and 3.09 % of Rethink Priorities’ (RP’s) mainline welfare range of silkworms. I underestimated the increase in the welfare of soil animals due to assuming none of the land use regards the expansion of pastures, which I estimate have 41.1 % (= (-3.40 - (-5.77))/ABS(-5.77)) more welfare per unit area than crops.
I got the absolute value of the change in the QALYs of directly affected animals per food-kg multiplying the aforementioned increase in animal-years in directly affected animals per food-kg by the absolute value of estimates for the decrease in the QALYs of directly affected animals per animal-year, which I obtained from the product between this decrease as a fraction of the welfare range of the target animals, and RP’s mainline welfare ranges. I set the decrease in the QALYs of directly affected animals per animal-year as a fraction of the welfare range of the target animals to:
For shrimp, 8.77, as I got for increasing the living time of shrimp on an ongrowing farm with air asphyxiation slaughter.
For fish, chicken, turkey, and pork, 2.27, as I got for increasing the living time of broilers in a conventional scenario.
For eggs, 1.69, as I got for increasing the living time of laying hens in a conventional cage.
For beef, and dairy milk, -1/3, which is my guess. It is negative, thus representing an increase in the QALYs of directly affected animals, because I expect cows to have positive lives.
I illustrated above why I think animal farming impacts soil nematodes, mites, and springtails hugely more than directly affected animals. My best guess isthat those soil animals have negative lives, so I think decreasing their animal-years by increasing land use is beneficial. Below are the m2-years per food-kg fromPoore and Nemecek (2018).
The above are mean values. They do not apply to every single case. Nevertheless, I infer the following replacements are generally beneficial due to increasing land use:
Plant-based foods, farmed shrimp (prawns), eggs, or farmed fish with poultry or pig meat.
Poultry or pig meat with cheese.
Cheese with beef.
I believe broadly advocating for decreasing the consumption of animal-based foods tends to be harmful. I predict it decreases cropland due to predominantly resulting in the replacement of poultry and pig meat, and beef with plant-based foods. In agreement with this, I estimated School Plates in 2023, and Veganuary in 2024 harmed soil nematodes, mites, and springtails 5.42 k and 3.58 k times as much as they benefited directly affected animals.
I am glad farmed shrimp are the animal-based food from Poore and Nemecek (2018) requiring the least agricultural land per food-kg. This means replacing farmed shrimp with other animal-based foods tendentially increases cropland, thus having the added benefit of increasing the welfare of soil nematodes, mites, and springtails.
My recommendations
I recommend donating to HIPF from CEARCH. I estimated its cost-effectiveness is 20.3 times the past one of SWP’s HSI, 13.0 kQALY/$, due to increasing the living time of humans by 0.189 human-year per $, and therefore increasing cropland by 1.34 k m2-years per $, and decreasing the living time of soil nematodes, mites, and springtails by 2.84 billion animal-years per $, which is super good given my best guess they have negative lives.
It is unclear to me whether soil nematodes, mites, and springtails have positive or negative lives. I calculated they have negative lives with a probability of 58.7 %, 55.8 %, and 55.0 %. I do not think effects on them can be neglected just because they are uncertain. Nevertheless, I consider it very worth it to decrease the uncertainty about how interventions affect the living time of soil nematodes, mites, and springtails, and about their welfare in QALY/animal-year. In particular, it is crucial to know whether they have positive or negative lives.
Eating plant-based still makes sense to me
I have been eating fully plant-based for 6 years, and plan to continue. My whole-food plant-based diet is cheaper than a standard diet, so it allows me to donate more, and I think the increased impact from this is larger than the harm caused by eating more plant-based foods. I estimated buying beef, which I believe is the most cost-effective way of increasing animal welfare through diet, has a cost-effectiveness of 408 QALY/$, 3.14 % (= 408/(13.0*10^3)) of HIPF’s, for a cost of 6.32 $/meat-kg. Consequently, I infer buying food which is cheaper than this by more than 0.198 $/food-kg (= 0.0314*6.32), and donating the savings to HIPF increases animal welfare more. Legumes are generally cheaper than beef by much more than that.
I also expect a whole-food plant-based diet to increase my donations as a result of being healthier, and therefore decreasing my spending on health, and increasing my future earnings via extending my life. From Willett et al. (2019), the global adoption of a predominantly plant-based healthy diet, with just 13.6 % (= (153 + 15 + 15 + 62 + 19 + 40 + 36)/2500) of calories coming from animals (as implied by the values in Table 1), would decrease premature deaths of adults by 21.7 % (= (0.19 + 0.224 + 0.236)/3; mean of the estimates in Table 3).
I see the above as arguments for focussing on increasing donations, not for following a vegan lifestyle, or eating fully plant-based. I do not specifically look for vegan supplements, or non-food products. They are often more expensive, and I do not expect them to be better. In contrast, I expect whole plant-based foods to be healthier than animal-based foods.
Acknowledgements
Thanks to Aro Roseman for clarifications about Faunalytics’ estimates, and to Michael St. Jules for feedback on the draft. The views expressed in the post are my own.
Debate: organisations using Rethink Priorities’ mainline welfare ranges should consider effects on soil nematodes, mites, and springtails, or at least be transparent about their reasons for neglecting them?
Despite my criticisms/thoughts below, how has no organization (RP, ACE, AWF, etc.) hired @Vasco Grilo yet? He's published extremely detailed good quality stuff just in his spare time and with a little bit of guidance/directional thought, I think he would be a great addition to many, many organizations out there.
Thanks, Marcus! I would also be happy to work for free for Ambitious Impact (AIM; @CE), @Animal Charity Evaluators (ACE), Animal Welfare Fund (AWF; @KarolinaSarek🔸), @Open Philanthropy (OP), @Rethink Priorities (RP), The Navigation Fund (TNF; @Jesse Marks), and some other impact-focussed organisations. For examples, reviewing docs or sheets.