everyone matters - so if we can help birds in ways that seem cheap and straightforward we should do it

Imagine an intervention can help a group of people "in ways that seem cheap and straightforward", but this may decrease human welfare due harming a much larger group of people, and that overall you are very uncertain about whether the intervention increases or decreases human welfare (in expectation). To increase human welfare, it would be reasonable to invest less in that intervention, and instead pursue ones which decrease the uncertainty about its effects, or ones which robustly increase human welfare? I agree that everyone matters, but this is precisely what makes me more pessimistic about bird-safe glass. I think one should account for effects on all potential beings.

Now even more importantly, I think we shouldn't even think in this way. If we conclude that extra years of life are net negative for birds, what should we do? Should we go and kill all birds?

The welfare of birds can be increased by decreasing the number of birds with negative lives, but also by improving their lives (making them less negative or positive), and this may increase the welfare of birds more cost-effectively. Would you oppose killing a bird if this was the most cost-effective way of increasing its welfare? If yes, do you oppose euthanising pets even when this is the most cost-effective way of increasing their welfare?

I know this, but I think offsets can help us escape it.

Money used for offsets can be used for other altruistic purposes. For example, according to Animal Charity Evaluators (ACE), The Humane League (THL) helped 11 chickens per $ in 2024, and the Shrimp Welfare Project's (SWP's) Humane Slaughter Initiative (HSI) helped 10.4 k shrimps per $ in 2024. So one has to decide between helping 1 chicken or 945 shrimps (= 10.4*10^3/11).

eating bugs might even be useful... Maybe it is way to keep insect population from exploding

I do not understand. Catching wild insects for human consumption would be more expensive than increasing the production of farmed insects, and this would require a greater population of farmed insects.

First of all, all people are in the same category according to most moral theories.

Which moral theories put birds and insects in different categories?

Second interventions that help one group of people and harm other group even more don't seem like they could look good on any intuitive measure. It would seem like some form of exploitation, slavery, war, genocide, or something like this, which doesn't look good.

The actions you have in mind described by the above have looked intuitive to lots of people at certain points in history, even if they were described differently when they were performed?

Third, windows are not a natural part of environment, it's something introduced by us, that directly harms birds. Predation of worms and bugs by birds has always been there and it might have benefits for the birds, for the ecosystem, and perhaps even for the bugs, if it keeps their number in check and avoids overpopulation, which could result in much worse life conditions, hunger, etc... Of course it won't help the insect that's eaten, but it might help the population of insects as whole by controlling their population.

Vaccines are not naturally part of the human environment, and the diseases they mitigate could be a good way of keeping human population in check, even though they harm the people who suffer from them?

Thank you for the comment, Zlatko.

I agree with your logic, but I'm wondering how you psychologically deal with this?

I sometimes feel a bit demotivated that increasing welfare seems very hard. However, I try to focus on what I can do to improve the situation. I also find comfort in determinism. I already thought I could not contribute to a better or worse world even before learning about effects on soil animals. I believe what I do (or, more precisely, the probabilities of my potential actions) is fully determined by the laws of physics.

Here's the most uncomfortable part and what I'm genuinely afraid of: it is the possibility to arrive at negative conclusion about an intervention that is by our very strong intuitions very positive, benevolent and altruistic, and that probably does, indeed help birds.

I am not confident that bird-safe glass increases the welfare of birds. From Mal's post:

Birds saved from window collisions don't become immortal — they die later from other causes, most commonly predation, as far as we can tell (Hill et al., 2019). Based on age-structured mortality models for affected species like song sparrows, collision victims who survive gain approximately 1–2 additional years of life^[1]. Whether this is net positive depends on comparing the suffering of window collision deaths versus alternative deaths (predominantly predation), plus the value of those additional life-years. Critically, if the difference in the amount of suffering caused by the new death outweighs the joy gained from an additional 1–2 years of life, the intervention could be net negative for birds themselves. Whether you think this is possible or likely depends both on empirical facts we don’t currently have access to, as well as philosophical beliefs about what makes a life worth living.

I personally think this is not a good approach. I think this constant triage is very cruel and cold as it directly puts interests of one group directly against the interest of other group.

We are always in triage?

My approach would be to let interventions benefiting birds be about birds without worrying about effects on arthropods, while at the same time trying to directly help arthropods as well, by some other interventions directly aimed at arthropod welfare.

Would you advocate for bird-safe glass if it increased the welfare of birds, but robustly increased suffering, and robustly decreased happiness accounting for effects on soil animals and microorganisms?

Since you care a lot about arthropods and soil animals and think that their welfare should dominate our moral concerns

I can see the total welfare of soil animals being practically negligible or all that matter. For individual welfare per fully-healthy-animal-year proportional to "individual number of neurons"^"exponent", and "exponent" from 0 to 2, which covers the best guesses that I consider reasonable, I estimate that the absolute value of the total welfare of soil ants, termites, springtails, mites, and nematodes is 2.04*10^-5 to 17.9 billion times the total welfare of humans.

maybe it would be valuable to try to think of interventions that could directly help them without hurting other animals or damaging the whole ecosystems

I agree. I do not recommend pursuing interventions aiming to change land use, or decrease the welfare of non-soil animals.

I recommend research on i) the welfare of soil animals and microorganisms, and ii) comparisons of welfare across species.

So my take is that concern for arthropods and concern for other beneficiaries should not be mixed. It should be two separate things. Both are worthy and valuable, but one should not be judged in terms of other.

Would you advocate for an intervention which harms a group of people A much more than it benefits another group of people B? If not, one should also consider not advocating for an interventions which may harm a group of animals C much more than it benefits another group of animals D?

Also, interventions that directly help arthropods and soil animals could plausibly have more effects on their welfare than interventions where effects on arthropods and soil animals are just a side effect.

I agree.

Or maybe you think "here's another example showing how indirect effects on tiny animals may dominate" and that this will convince some people to also prioritize (i) and (ii)? (people who were not convinced by your previous largely-overlapping posts but might by this one?)

I was mostly motivated by this, but I would not be surprised if my post ends up having a very minor effect.

Hi Jim. No. For all the non-research interventions I am aware of, including all on Rethink Priorities' (RP's) Wild Animal Welfare Intervention Database (WAWID), I think the effects on soil animals or microorganisms may be much larger than those on the target beneficiaries. So I recommend decreasing the uncertainty about the effects on soil animals and microorganisms via research on i) their welfare, and ii) comparisons of welfare across species.

Hi Mal.

We don’t know if bird-window collisions affect bird population sizes. If populations are resource limited, preventing collision deaths might not increase population size — it might just shift which individuals die and how they die. If populations do increase, though, this creates cascading effects on prey species (primarily insects); scavengers who feed on collision victims; other animals who compete with birds for space, food, or other resources; and broader ecosystem dynamics.

I think replacing standard with bird-safe glass may impact arthropods much more than birds.

Hi Ben and Richard.

We’ve already started engaging policymakers on wild animal-friendly urban infrastructure (e.g. bird-safe glass). [...]

[...]

• Supporting an existing amendment which would mandate bird-safe glass in new buildings. We provided advice and research on European bird-safe glass legislation and regulation, and generated positively-framed media coverage (e.g. in The Guardian).

I think replacing standard with bird-safe glass may impact arthropods much more than birds.

Hi David. Thanks for the post.

I have an annual reminder to tell my closest family about the charities I would like to leave 90 % of my assets to if I die. I tell them they could take the other 10 %, which I think results in a greater fraction going to charity than if I told them to leave 100 % to charity.

I considered setting up a will, but I concluded it is not worth it for me. I estimate it would cost 234 € for financial cost of 159 € in Portugal, and time cost of 75 € for 5 h at 15 €/h. The risk of death of people in Portugal in 2023 with age 25 to 29, which covers my age, was 0.0416 %. So it would only be worth it if I could lose more than 562 k€ (= 234/(4.16*10^-4)). My total assets are much smaller than this, and I expect this to continue to be the case. I aim to keep my savings equal to 6 times the global real gross domestic product (GDP) per capita, which is currently around 80 k€ in Portugal.

I replied here.

Do you think pain A having a higher intensity than B implies that averting an infinitesimal duration of pain A with an infinitesimal probability is better than averting an astronomically long time of pain B with certainty? If not, what is required for you to believe this besides A having a higher pain intensity than B?

Consider someone holding their hand in hot water for 1 min. If you think there are only 5 pain intensities, what would be the range of temperature for each pain intensity? If the ith pain intensity starts at T_(i - 1), and ends at T_i, what would change so much from temperature T_i_before = T_i - 0.001 ºC to T_i_after = T_i + 0.001 ºC that makes you prioritise averting pain at T_i_after infinitely more than pain at T_i_before? Do you believe empirical studies of people's preferences would find a few temperatures (4 if you believe in 5 pain intensities) with this property, where people would prefer averting any time in pain at temperature T_i_after over an arbitrarily long time in pain at temperature T_i_before?

Hi Vince.

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This just links to their logo. Here is ACE's review.