Thanks for your questions. I’ll let Marcus and Peter answer the first two, but I feel qualified to answer the third.
Certainly, the large number of invertebrate animals is an important factor in why we think invertebrate welfare is an area that deserves attention. But I would advise against relying too heavily on numbers alone when assessing the value of promoting invertebrate welfare. There are at least two important considerations worth bearing in mind:
(1) First, among sentient animals, there may be significant differences in capacity for welfare or moral status. If these differences are large enough, they might matter more than the differences in the numbers of different types of animals.
Hi Dan,
Thanks for your questions. I’ll let Marcus and Peter answer the first two, but I feel qualified to answer the third.
Certainly, the large number of invertebrate animals is an important factor in why we think invertebrate welfare is an area that deserves attention. But I would advise against relying too heavily on numbers alone when assessing the value of promoting invertebrate welfare. There are at least two important considerations worth bearing in mind:
(1) First, among sentient animals, there may be significant differences in capacity for welfare or moral status. If these differences are large enough, they might matter more than the differences in the numbers of different types of animals.
(2) Second, at some point, Pascal’s Mugging will rear its ugly head. There may be some point below which we are rationally required to ignore probabilities. It’s not clear to me where that point lies. (And it’s also not clear that this is the best way to address Pascal’s Mugging.) There are about 440 quintillion nematodes alive at any given time, which sounds like a pretty good reason to work on nematode welfare, even if one’s credence in their sentience is really low. But nematodes are nothing compared to bacteria. There are something like 5 million trillion trillion bacteria alive at any given time. At some point, it seems as if expected value calculations cease to be appropriately action-guiding, but, again, it’s very uncertain where to draw the line.