Thanks for the great post, Rory. In reality, I think the intended output often increases as any of the input factors increases. However, your point remains that increasing the most limiting input factor may increase the output much more than increasing other input factors.

Level 1: Ignorable (40°C – 43°C)

I think you meant 44 ºC instead of 43 ºC. Level 2 starts at 44 ºC.

1-) As I stated earlier, duration is not just a multiplier; it is a catalyst for a qualitative shift. ( In the context of my Five-Phase Model, after a certain threshold, a prolonged Level 3 experience does not simply "add up" to a large Level 3 sum, it undergoes a functional priority shift, effectively transforming into a Level 4 state for example.)

It makes sense the maximum level of pain increases with duration, but I do not think this solves the core issue. There will still be very small changes in temperature or duration leading to a change in the level of pain. Consider the function f(T = "temperature of the water", t = "time with a hand under water") which outputs the highest level of pain (1 to 5). Below is an illustration from Gemini. It assumes the temperature ranges you provided apply to a duration of 1 min, and the level of pain increases with duration as you mentioned. The specific shape of the boundaries between pain level is not important. What matters is that boundaries exist. Imagine 45 ºC for 3 min separates the levels of pain 2 and 3, as it is roughly the case below. Would you prever averting i) 45 ºC for 3 min 0.1 s (maximum pain level of 3) for 1 person with probability 10^-100 over ii) 45 ºC for 2 min 59.9 s (maximum pain level of 2) for the 8 billion people on Earth with certainty? i) corresponds to 1.80*10^-98 s (= (3*60 + 0.1)*1*10^-100) of level 3 pain in expectation, and ii) to 1.44*10^12 s (= (2*60 + 59.9)*8*10^9*1) of level 2 pain in expectation. I understand you would prefer averting i) because you prioritise averting level 3 pain infinitely (lexically) more than averting level 2 pain. I do not understand this. People would not distinguish between 45 ºC for 3 min 0.1 s (maximum pain level of 3), and 45 ºC for 2 min 59.9 s (maximum pain level of 2).

You are welcome. Feel free to get in touch in the future if you want me to have a look at other CEAs of animal welfare interventions.

Hi Alfredo. Thanks for the great post.

I think your question was relevant. I did not feel like you were derailing the post. Thanks for the support.

Hi Cynthia. Thanks for the helpful clarification. Are there any medical conditions that make people regularly experience excruciating pain (for example, for a few minutes per week)? Maybe people suffering from cluster headaches?

Thank you too for making me understand your perspective better. I think it is shared by many people.

Could you recommend any charity directly concerned with soil animals and arthropods that you think is good and that you yourself donate to? I'd like to know, perhaps I could donate some.

Also I'm wondering if they do just research at this phase, or are they already actively helping?

I am glad you are open to supporting work targeting invertebrates. My top recommendation for this is funding the Arthropoda Foundation. I donated a few k$ to them last year. Here is the post announcing their launch, and here is their post during the last Marginal Funding Week. They have been funding research informing how to increase the welfare of farmed arthropods, and "are particularly interested in research with a clear path to impact, whether by shaping future science or informing real-world decision-making".

Hi.

"I speculate birds cause 1 s of excruciating pain to each arthropod they eat. So I estimate the decrease in the welfare of each arthropod is equal to that from them losing 24 h of fully healthy life" 

Did you just equal 1 second of suffering to a whole day of good life? 

The sentence before the one you quoted above has the additional context.

I guess I am roughly indifferent between 1 s of excruciating pain, like “severe burning in large areas of the body, dismemberment, or extreme torture”, and losing 24 h of fully healthy life. I speculate birds cause 1 s of excruciating pain to each arthropod they eat. So I estimate the decrease in the welfare of each arthropod is equal to that from them losing 24 h of fully healthy life (= 24*60/22.4).

I assume that 1 s of excruciating pain (very extreme suffering) is as bad as losing 24 h of fully healthy life.

I like Peter Godfrey-Smiths concept of a life worth living and the thought experiments that come with it. So basically you get to decide if you want to be reborn and live the life of certain animal or not. If you say you would take the chance to live a certain life, you consider this to be a life worth living.

I like this thought experiment too.

If some people feel that 1 second of excruciating pain is worth 24 hours of living while others think it's not a big deal you can just type in any numbers in your calculations in order to get the result you want.

My conclusions do not depend on whether arthropods have positive or negative lives. "For simplicity, I ignore changes in the population of arthropods", and I still conclude bird-sage glass may impact arthropods much more than birds.

But we should probably take care about ourselves first and make the world robustly good for humans. I wouldn't feel particularly good about myself letting kids die due to concerns for insects or even chicken.

Do you think there should still be some spending on animal welfare? Each 4 k$ or so spent on animal welfare could have saved one child if donated to GiveWell's top charities.

The ill dog can even have some real fun in last days with morphine or other drugs (I'm not joking... opioids cause euphoria and pleasure to everyone)

Interesting perspective.

Maybe you're right if we're strictly thinking on margin. In this case you can say, on margin, for me it's best to help arthropods. And it might indeed be the case. In your particular case you have this kind of luck that your visceral care is so well aligned with utilitarian calculus. So you can help arthropods and feel great about it.

Yes, I am thinking at the margin. I believe soil animals are very neglected in the current portfolio of animal welfare interventions. The animal advocacy movement spent around 259 M$ in 2024. The vast majority was spent on farmed animals, and almost nothing on soil animals. I am only aware of 2 projects on soil invertebrates funded by WAI on spiders totalling 56.9 k$ (= (29.9 + 27.0)*10^3). If one of these happened in 2024, spending on research on soil invertebrates was 0.0110 % (= 56.9*10^3/2/(259*10^6)) of that targeting farmed animals. In contrast, I estimate there are 959 M times as many soil animals as farmed animals, and that soil animals have 13.6 k times as many neurons in total as farmed animals. The ratio between total number of neurons and spending is 124 M (= 13.6*10^3/(1.10*10^-4)) times as large for soil animals as for farmed animals. I am very uncertain about whether the total number of neurons is a good proxy for potential benefits, but I see it as a reasonable option.