Should we consider the welfare of small soil animals? On the special relativity of welfare
There are interesting discussions on the Effective Altruism Forum concerning the welfare of the smallest but most abundant animals: Should we consider effects on soil nematodes, mites, and springtails? And does animal farming impact soil nematodes, mites, and springtails hugely more than directly affected animals?
If tiny soil animals such as nematodes have on average a negative welfare overall, even if that level of suffering is small, the numbers of those animals are so large that the total suffering of all soil animals could easily be larger than the total suffering of for example farmed animals. In agricultural land, there are much less nematodes than in natural habitats, such as forests. Animal farming increases agricultural land and hence strongly decreases the populations of soil animals on earth. If there are fewer soil animals, there is less soil animal suffering. Could the decrease in suffering of soil animals be larger than the increase in suffering of the farmed animals? In other words: could animal farming be net beneficial, by slightly increasing farmed animal suffering but strongly decreasing soil animal suffering? Could veganism be counterproductive and increase the total suffering on earth, by strongly increasing the suffering of nematodes?
The crucial consideration is whether those small soil animals have a positive or negative welfare significantly different from zero. My best guess is that for those animals, their average welfare is indeterminate or incommensurable with zero. A zero welfare is by definition the welfare level at which one is indifferent with non-existence: experiencing a life at zero welfare is as preferable as not experiencing anything at all. Incommensurable with zero means that the welfare is neither clearly positive, nor clearly negative, nor clearly zero. In other words: I believe a nematode’s welfare cannot be clearly, objectively or absolutely compared with a state of non-existence, not even in principle, if one had the most accurate welfare measurement device.
For this reason of incommensurability, I believe we can neglect population-changing effects on animals with indeterminate welfare levels. When animals have welfare levels incommensurable with zero, it becomes meaningless to say that the total welfare of those animals increases or decreases when the population size of those animals changes. The effects of agriculture on nematodes are such population-changing effects (agriculture decreases the population sizes of small soil animals), and hence can be neglected. I’m uncertain whether this also applies to insects and other small invertebrate animals: are their welfare levels also incommensurable with zero, such that we can neglect population-changing effects of agriculture on insects?
To explain this in more detail, let’s first introduce some definitions. The welfare range of a sentient being is the range of its welfare levels, from the most intense suffering that the sentient being could possibly experience to the highest happiness achievable. Also humans have a welfare range, and I believe that the welfare range of a nematode is much narrower or smaller than that of a human. If a nematode is not sentient and has no consciousness, its welfare range is zero: it cannot experience any welfare.
A welfare frame is a way of gauging or calibrating someone’s welfare, or more precisely: a way of comparing the welfare of someone’s life with non-existence. A welfare frame determines the zero-point welfare. But it is possible that there are many valid welfare frames. As I will explain, this is comparable to a reference frame in Einstein’s theory of relativity. If the speed of light is finite, we have a relativistic space-time continuum with many reference frames. If the speed of light is infinite, we have an absolute, Newtonian space-time with only one reference frame.
The neutral range of a sentient being is the range of welfare levels that are incommensurable with zero, meaning that for each welfare level in the neutral range, there is always a valid welfare frame according to which that welfare level is zero.
The crucial consideration is the welfare sign of a nematode. If there is only one unique welfare frame, there is a determinate welfare sign of a nematode: it is either positive or negative (or zero). Animal farming is very good if a nematode’s welfare is negative and very bad if it is positive, because the welfare effects of the nematode population dominate the welfare calculations. Nematodes dominate, even if their welfare levels and welfare ranges are very small, because there are so many nematodes. Some people believe the welfare sign of a nematode is negative, others say it is positive. I expect most people believe it is around zero. There does not seem to be any consensus about the welfare sign of a nematode. A question I would ask is: would the most empathic veterinarians prefer to euthanize a nematode, like they prefer to euthanize a dog when that dog has a negative welfare? I doubt it, which means nematodes do not seem to have a negative welfare. Would the most empathic total utilitarians (who want to maximize total welfare) prefer to breed more nematodes, like they prefer the existence of more individuals with positive welfare? I doubt it, which means the nematode welfare is not positive either. Would those people believe that all nematodes happen to have exactly 0 welfare? I doubt it: what a coincidence would that be? So a nematode’s welfare is not clearly negative, not clearly positive, and not clearly zero. Then what is it? It’s indeterminate, or incommensurable with zero. There is no objective, unique, absolute sign of a nematode’s welfare. The incommensurability with zero means for example that a nematode with welfare X can be considered equally good as a non-existing nematode, and increasing that nematode’s welfare with a tiny amount dX, such that its welfare becomes X+dX, can still be considered equally good as non-existence. This may seem paradoxical, but a similar paradoxical thing happens in relativity theory.
The incommensurability may be intrinsic because we have no clue how we can possibly answer this question whether a nematode’s welfare is positive or negative, what research method we could possibly use to determine the welfare sign. This is even more difficult than determining whether a nematode is sentient. I don’t expect a solution popping up somewhere the next few decades. I think the question whether the welfare of a nematode is positive or negative, is ill defined. According to one welfare frame, the nematode has a negative welfare, but according to another, equally valid welfare frame, the welfare is positive.
This can be compared with Einstein’s theory of special relativity, where the incommensurability of time is also intrinsic. The moment ‘now’ for another observer (like the welfare ‘zero’ for another sentient being) is ill defined and depends on your frame of reference (e.g. whether you move towards or away from that observer). Suppose you and I have super accurate clocks. I determine that “now!” corresponds with time zero on my clock. My “now!” is a space-time event: something that happens at a specific location in space and time. Relative to my “now!”, there are events in the past and future. But suppose you also determined your “now!” as time zero on your clock. And suppose that a signal that starts at my “now!” has to travel faster than light in order to arrive in time at your space-time event “now!”. Technically, we say that your “now!” lies outside the lightcone of my “now!”. The question is: is your “now!” in the future or the past of my “now!”? When the speed of light is finite, this question is always ill-defined, even if we had infinitely accurate clocks. You can always pick a reference frame according to which your “now!” exactly corresponds with time zero on my clock. And pick another reference frame according to which your “now!” is in the future of my “now!”. And according to a third reference frame, your space-time event is in my past.
In the analogy, the time of your “now!” on my clock corresponds with the welfare of the nematode relative to non-existence. My “now!” corresponds with zero welfare of non-existence, your “now!” corresponds with the welfare of the nematode. If your “now!” is in the future (past) of my “now!”, that corresponds with a positive (negative) welfare of the nematode. The different reference frames in special relativity correspond with different ‘welfare frames’ of the nematode.
The multitude of reference frames result in a weird kind of intransitivity in special relativity, where space-time events X and Y happen simultaneously (at time 0), space-time event Z is in the future of Y, and yet events X and Z also happen simultaneously (at time 0, but according to another reference frame). There is a similar strange kind of intransitivity of welfare: a nematode in state X (non-existence) and Y have the same welfare (equal to 0), the nematode in state Z is strictly happier than in Y, and yet there is a welfare frame according to which states X and Z are equally good (welfare 0). This intransitivity does not make the notion of welfare inconsistent, just like the intransitivity in special relativity does not make the notion of time inconsistent. Time is relative but consistent, and so is welfare. In special relativity, time is a continuous variable that can in principle be measured with infinite accuracy. So, the notion of time makes perfect sense in the theory of special relativity, but the notion of “now” does not. Similarly: the notion of welfare makes perfect sense in moral theories such as hedonism, but the notion of zero welfare does not.
As a human, I can compare my welfare with non-existence to a high degree, but not infinitely accurately. In the special relativity analogy, this corresponds with a space-time continuum in which the speed of light is very high. But for the nematode, the comparison with non-existence is much more difficult, which would correspond with a space-time with a very low speed of light. If the speed of light is extremely low, or say zero, almost all your space-time events are outside of my light cone, which means you can pick any moment along your timeline and I can pick a reference frame according to which that moment is simultaneous as my “now!”. With the nematode: give me any full description of its experiences, the physical forces that it feels and so on, and I can pick a welfare frame according to which that nematode has a zero welfare, and you can pick another welfare frame according to which that same nematode, with the very same experiences, has a negative welfare. And someone else can validly derive a positive welfare for that very same nematode. There is no objective way to determine which of our welfare frames is the correct one.
I believe a nematode’s welfare range is so small, that it is smaller than its neutral range, meaning that all its experiences that it could possibly have always correspond with a welfare level that is incommensurable with zero. A nematode may not be able to compare its welfare with non-existence. Even for me it may be hard to compare my welfare with non-existence: I find it difficult to imagine the exact level of welfare at which I would be indifferent with non-existence. My neutral range may be small, but is not zero.
I believe there is not always a straightforward answer when one’s welfare is at a similar level as non-existence. Just as in special relativity, there is not always a straightforward answer when a space-time event happens now. For sentient beings with large brains, such as humans, their neutral ranges may be small compared to their welfare ranges. Sentient beings with smaller brains may have both larger neutral ranges and smaller welfare ranges. In extremis, a nematode with only 300 neurons may have a very small welfare range that lies entirely within its wide neutral range. A nematode cannot reach such intense levels of misery to say that its welfare is absolutely, objectively negative, i.e. negative according to all welfare frames.
The ratio of the welfare range to the neutral range corresponds with the speed of light in the special relativity analogy. A nematode has a much lower “welfare speed of light” than a human. A neutral range of zero corresponds with an infinite speed of light, which means there is only one, absolute reference frame or welfare frame. If the neutral range is very large, the welfare speed of light is small. At an infinite neutral range, all welfare frames are valid and no welfare level is commensurable with zero. Similarly, at a zero speed of light, all reference frames are valid and all moments on your timeline are incommensurable with my “now!”.
The organization Rethink Priorities did a great job estimating the welfare ranges of different kinds of animals. The open question is: how can we determine or estimate the neutral ranges of different sentient beings?
Further reading:
Relativistic welfare, farm animal abolitionism and wild animal welfarism
I don’t quite see the connection here between having a small welfare range and having an indeterminate welfare sign. Suppose a being is only capable of having very slightly positive experiences. Then it has a very small welfare range but it seems to me that its welfare range is determinately positive. It has positive and no negative experiences.
There is some plausibility to the idea that there may not be uniquely correct ways of weighing different experiences against each other. E.g., perhaps there is no uniquely correct answer to how many seconds of a pleasant breeze outweigh 60 minutes of a boring lecture, or how many minutes of the intellectual enjoyment of playing chess outweigh the sharp pain of a bad papercut, even if there are incorrect answers (maybe one second of the breeze is definitely not enough to outweigh the lecture). This may be plausible in light of the Ruth Chang-type intransitivity arguments: if I am indifferent between X seconds of the breeze and 60 minutes of the lecture, I might also be indifferent between X + 1 seconds of the breeze and 60 minutes of the lecture even though I obviously prefer X+1 seconds of the breeze to just X seconds, and it’s not clear that this is merely an epistemic issue. If, as came up in your discussion with Vasco, someone wants to understand one’s experience outweighing another’s as being a matter of what you would prefer (rather than a realist understanding on which the outweighing comes first and rational preferences will follow), this perhaps seems especially plausible, as I doubt our preferences about these things are, as a matter of descriptive psychology, always perfectly fine-grained.
in that case, I could see it being the case that it’s sometimes indeterminate whether a being has positive or negative welfare because it has lots of very different types of experiences which sort of come out closely matched with no uniquely correct weighting. But that is orthogonal to the size of the welfare range: that could turn out to be true even if the individual experiences are really (dis)valuable.
I implicitly assumed the welfare range includes zero.
About the intransitivity argument: The comparison of the X seconds of breeze and the lecture is a coarse-grained comparison, i.e. in a coarse-grained frame. Also comparing X+1 seconds of breeze with the lecture is in a coarse-grained frame. But comparing X with X+1 seconds of breeze is fine-grained. So the comparisons assume different frames, as with reference frames in special relativity and welfare frames in utilitarian ethics.
I guess I’m not getting how this responds to my point. Suppose my welfare range (understood as representing the range of positive and negative experiences I can have) goes from -.01 to .01. I say I might have determinately positive welfare because, as a matter of fact, all, or the predominant majority of, my experiences are slightly positive. Otoh, suppose my range goes from −1000 to 1000. I say (I am open to the possibility that) it might be indeterminate whether I have positive welfare because I have a bunch of importantly different types of positive and negative experiences that are kind of closely matched without a uniquely correct weighting. So the indeterminacy is not related to the size of the welfare range but rather to having importantly different types of positive and negative experiences that are kind of closely matched without a uniquely correct weighting, or something like that. It could still be that it’s indeterminate whether nematodes have positive or negative welfare, but that won’t be just because their welfare range is small.
What’s your answer to that?
I guess you’re suggesting that the neutral range is not well-defined? When experiences are composed of positive and negative parts without correct weighting, the neutral range could be larger than when experiences are more dominated by either positive or negative parts? I’m open to such a possibility.
As far as I can see, there just isn’t such a thing as a neutral range. An individual could have an arbitrarily small welfare range and still have determinately positive or negative net welfare, or (I am open to the possibility of) an arbitrarily large welfare range while being such that it’s indeterminate whether their net welfare is positive or negative. And so noting that nematodes have small welfare ranges doesn’t tell us anything about this in and of itself.
Perhaps we should run a survey, ask people if they have a neutral range. Can they give values of X, Y and Z such that if they would experience X, Y and Z units of some welfare determining components, they would be indifferent between that experience and non-existence, whereas if they had X+dX, Y and Z units, they would state a positive welfare and X-dX, Y and Z units would correspond with a negative welfare. I’m personally very skeptical that most people’s neutral ranges are zero. You claim to have a zero neutral range?
So my view is that if I have (X,Y,Z) at (0,0,0), which is equal to nonexistence, then (.01,0,0) is positive and (-.01,0,0) is negative. Why wouldn’t it be? Why wouldn’t a life with a slight positive and no negatives be positive? And presumably, say, (.01,0,-.00000001) will also be positive.
I think people frequently conflate there being no reason for something and there being very little reason. E.g., they’ll say “there is no evidence for a flat earth” when there is obviously some evidence for it (that some people believe in it is some evidence). If people say (.01,0,0) is not better than non-existence, I’d suspect that’s what they’re doing.
Ok, let me exaggerate a bit. Assume when state S=(X,Y,Z)=(87455.668741, −258.142567, −11024.441253), you are indifferent with nonexistence. Now consider state S’=(87455.668741, −258.142567, −11024.441153). You can confidently say that S’ gives you a positive welfare? If yes: close your eyes and write down, for the given X and Y of state S, a value of Z that gives you a positive welfare lower than S’. I bet your brains are too small to do this exercise. Now consider a nematode with much smaller brains....
So I understand: are you denying that the life with a tiny bit of positive welfare and no negative welfare, or the life with a tiny bit of positive welfare and a tiny tiny tiny tiny tiny bit of negative welfare, is determinately net positive? If so, I think that is an important crux. I don’t see why that would be.
I guess it had better not be a question of whether, as a matter of actual fact, I have the brainpower to do the exercise (with my eyes closed!). Babies, I assume, have no concept of their own non-existence, and so can’t compare any state they’re in to non-existence, yet they can have positive or negative welfare. Or someone who lives long enough will not be able to remember, much less bring to mind, everything that’s happened in their life, yet they can have a positive or negative welfare. So what matters is, if anything, some kind of idealized comparison I may or may not be able to do in actual fact. (And in any event, I guess the argument here would not be that nematodes have indeterminate welfare because their range is small, but rather that they do because they are stupid.)
What I’m suggesting could be the case is a situation where, say, the correct weighting of X vs Z is not a precise ratio but a range—anything between 7.9:1 and 8:1, let’s say for the sake of argument—such that the actual ratio falls into this indeterminate range, and a small change in either direction will not cause a departure from the range. I see how that could perhaps be the case. But that kind of indeterminacy is orthogonal to the size of the welfare range. It would still hold if the values were .087455668741 and .011024441253 or 87455668741 and 11024441253, and wouldn’t hold if the values were .087455668741 and .010024441253.
You raised a good point. Yes, I guess I agree that when there is only a positive experience and no negative, the welfare is definitely positive, even if the positive experience is very small. But thinks get tricky when there are both positive and negative experiences, as is the case for almost all sentient beings, and probably also for nematodes if they are sentient. The more welfare is composed of positive and negative parts, the more difficult it becomes to compare it with a zero welfare level. Might have to do with information processing capacity. Adding up many positives and negatives is more difficult that considering a single positive or negative value. Evaluating mixed experiences (with both positive and negative parts) might require a more coarse-grained approach. The level of coarse-graining might relate to the neutral range: the more coarse-graining is used, the wider the neutral range.
Thanks for the post, Stijn! I strongly upvoted it, although I am not convinced at all. Readers may be interested in the discussion between me and Stijn about it.
I strongly disagree that effects on nematodes (or any other potential beings) can be neglected in principle.
There was an interesting paper a couple of years ago in one of the world’s best philosophy journals arguing that incommeasurability as understood in a lot of the philosophical literature simply isn’t possible: https://philarchive.org/rec/DORTCF-2 Though it’s not clear if the alternative view they like is really best described as one on which incommeasurability doesn’t exist at all, rather than as an alternative theory of incommeasurability on which it might still make sense to say the nematode welfare is in some sense not distinguishable from zero but not exactly zero either.
Thanks for the reference. I quickly read that paper, and at the very end the authors seem to defend what I interpret as an account of incommensurability (the part about context-sensitivity). Perhaps I misunderstand that paper, but anyway, I’m not yet convinced that incommensurability of welfare is impossible, in particular because of the analogy with special relativity, where time is really (mathematically) incommensurable: the notion of ‘now’ depends on the reference frame.
Executive summary: This exploratory post argues that the welfare of small soil animals like nematodes may be incommensurable with zero—meaning their welfare cannot meaningfully be compared to non-existence—and therefore population-level changes (e.g., due to agriculture or veganism) may not morally matter; this hinges on the speculative idea that welfare, like time in special relativity, is frame-dependent rather than absolute.
Key points:
Tiny soil animals are vastly numerous, and if their welfare is even slightly negative, they could dominate total suffering calculations—potentially even making animal farming net beneficial by reducing their populations.
The author argues that nematodes’ welfare is incommensurable with zero—not clearly positive, negative, or neutral—so we cannot say whether their existence adds to or detracts from total welfare.
Population-level impacts on such beings may be morally negligible: if we can’t meaningfully assign a welfare sign to their lives, increasing or decreasing their numbers doesn’t clearly raise or lower total welfare.
The concept of “welfare frames” is introduced, likened to reference frames in special relativity; just as simultaneity depends on the observer’s frame, so too might assessments of welfare depend on an observer-relative welfare frame.
This analogy implies that welfare is consistent but relative, and that for beings with small welfare ranges (like nematodes), all possible experiences might fall within their “neutral range”—making comparisons to non-existence ill-defined.
The post ends with a call for research into “neutral ranges” (not just welfare ranges), suggesting this could help clarify how we morally weigh the lives of small or simple organisms.
This comment was auto-generated by the EA Forum Team. Feel free to point out issues with this summary by replying to the comment, and contact us if you have feedback.