This is a crosspost for The Case for Insect Consciousness by Bob Fischer, which was originally published on Asterisk in January 2025.
[Subtitle.] The evidence that insects feel pain is mounting, however we approach the issue.
For years, I was on the fence about the possibility of insects feeling pain — sometimes, I defended the hypothesis;[1] more often, I argued against it.[2]
Then, in 2021, I started working on the puzzle of how to compare pain intensity across species. If a human and a pig are suffering as much as each one can, are they suffering the same amount? Or is the human’s pain worse? When my colleagues and I looked at several species, investigating both the probability of pain and its relative intensity,[3] we found something unexpected: on both scores, insects aren’t that different from many other animals.
Around the same time, I started working with an entomologist with a background in neuroscience. She helped me appreciate the weaknesses of the arguments against insect pain. (For instance, people make a big deal of stories about praying mantises mating while being eaten; they ignore how often male mantises fight fiercely to avoid being devoured.) The more I studied the science of sentience, the less confident I became about any theory that would let us rule insect sentience out.
I’m a philosopher, and philosophers pride themselves on following arguments wherever they lead. But we all have our limits, and I worry, quite sincerely, that I’ve been too willing to give insects the benefit of the doubt. I’ve been troubled by what we do to farmed animals for my entire adult life, whereas it’s hard to feel much for flies. Still, I find the argument for insect pain persuasive enough to devote a lot of my time to insect welfare research. In brief, the apparent evidence for the capacity of insects to feel pain is uncomfortably strong.[4] We could dismiss it if we had a consensus-commanding theory of sentience that explained why the apparent evidence is ir
Argument: The money can be spent over a long time and like will be able to be spent.
The footnote on the main question says:
Likewise @Will Howard🔹 argues that this isn't that significant an additional amount of money anyway:
Argument in favor of giving to humans:
Factory farming will stop at some point in this century80%, while human civilization could stay for a much longer time. So you can push humanity in a slightly better long-term direction by improving the circumstances in the third world, e.g. reducing the chance that some countries will want to acquire nuclear weapons for conflict because of wars because of famines.
So there's an option to affect trajectory change by giving to global health, but not really for animal welfare.
Argument: Approximations are too approximate.
@Henry Howard🔸 argues that much of the scholarship that animal welfare estimates are based on is so wide that that it doesn't make clear conclusions:
My response to this is that we can always take medians. And to the extent that the medians multiplied by the number of animals suggest this is a very large problem, the burden is on those who disagree to push the estimates down.
There isn't some rule which says that extremely wide confidence intervals can be ignored. If anything extremely wide confidence intervals ought to be inspected more closely because the value inside them can take a lot of different values.
I just sort of think this argumend doesn't hold water for me.
Argument: Nietzschean Perfectionism
@Richard Y Chappell🔸 theorises that:
To my (Nathan's) ears this is either a discontinuous valuation of pleasure and pain across consciousnesses or one that puts far more value at the higher end. In this way the improvement to the life of a human could be worth infinite insects or some arbitrarily large number.