I wasn't calling out you specifically, more explaining my attitude here in general. Sorry for not being more clear about that.
> My question would be, why not use humans? At what point would the "very high expected return" justify this? Never? Why not?
Very good question! Obviously we are heading into sci-fi territory now, but in a world where all suffering was valued according to some agreed-upon objective metric I would suggest the following:
- yes much more human testing, especially volunteers who are terminally ill/suicidal etc.
- in such a world testing would presumably be much more expensive, so they could afford more complex research substrates that we don't bother with because we can just use animals
- eg. lots of brain organoids and other synthetic experimental substrates
And for the record, I do think such a world would either be some sort of anarchocapitalist chaos or painfully slow to develop. But at least it would be morally coherent!
Joking aside I guess my only real message here is, people who find this stuff disgusting should think about their dinner plates. In my ideal world, we use approximately 50% as much animal testing and 0.1% as many animal food products.