Why would that reasoning apply only to certain animals and not others? If it's okay to be cruel to rats for the service of the greater good, then why not dogs, apes or dolphins? Why not humans? Where and how do you draw the line?

I'm not going to defend this study, but we already have a line between humans and nonhumans, particularly when legally speaking. For example, the sentences handed down for killing another human are far more severe than killing an animal. These lines already exist.

Well there is a line. I don't think twice using insecticide when confronted to a mosquito.

Killing a mosquito is an act of self preservation, as valid now as it was 10.000 years ago. Many of us live an existence pretty removed from the threats of the wild, but we we’re not totally detached from the need to “protect” ourselves. :)

The greater good is the slipperiest slope in the history of slippery slopes. Plus, this only "applies" if you are a utilitarian. The same rationale was used by the Nazi Scientists and the Japanese Unit 751 during WWII to justify psychopathically sadistic human experiements on POWs.

Sentient beings do not want to be brutally experimented on. This self-selecting industry of sociopaths belongs in the 19th century.

>Sentient beings do not want to be brutally experimented on

This is obviously false, because transplanting a uterus to a genetic male was done on a human, voluntarily, long before this experiment.

Well, they were capable of consent and consented. I also doubt that they had their circulatory system fused with another female human by surgically splicing them together. I imagine they would have declined if that were the case.

How her suffering and death (in 1931) compared with the rats is irrelevant to my point which is just about the value of the research to humans.

I can't argue whether someone should be concerned about humans or rats and how much and what experiments are worth it. How you balance one creature's suffering with another. Nobody can or has ever answered that.

I meant to counter the idea that transplanting a uterus has to be without purpose and can only be attributed to idle cruelty.

https://en.wikipedia.org/wiki/Lili_Elbe