Scientists do work to acquire knowledge but that must also be within the bounds of what is ethical. To work on humans or animals you have to apply to ethics committees and apparently the animal ethics committees are far more strict. Compassion and empathy is something that is valued when designing an experiment. Though you do mention that values back then were different, but it seems like there was scientific opposition to these experiments even at the time. It's things like this that led to the creation of ethics committees.
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind."
~John Stuart Mill~
Scientists do work to acquire knowledge but that must also be within the bounds of what is ethical. To work on humans or animals you have to apply to ethics committees and apparently the animal ethics committees are far more strict. Compassion and empathy is something that is valued when designing an experiment. Though you do mention that values back then were different, but it seems like there was scientific opposition to these experiments even at the time. It's things like this that led to the creation of ethics committees.
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind."
~John Stuart Mill~