Re Jainism, adherents practice lacto-vegetarianism, but they, for example, don't eat tubers because they consider them too advanced, if I understand correctly. A deep respect for all forms of life is hard to get right in a world where every living thing eats some other living thing, or dies.
edit: there are also just SO many ways moral philosophies start to diverge at that point. Like we're talking about what is "necessary" animal experimentation. It's an important question, and one that really does boil down to a personal exercise.
Like... Personally I have no idea how to answer it. If you remove animal experimentation, well there goes a bunch of carcinogen studies which could result in a lot of human suffering. I also would need to do a ton of research to figure out if BCI research is at a level where primate brains are necessary instead of simpler organisms.
I also need to examine my own lifestyle, since hypocrisy severely undermines moral positions and having integrity/cogent beliefs and actions is essential if we are to engage with these subjects honestly.
For example, personally I have sometimes consumed meat in the last year (although I generally avoid it). Supporting factory farming absolutely violates my deontological moral imperative that "it is wrong to cause unnecessary suffering to others", in a ton of different ways. So who am I to espouse views on how people should behave with regards to animal research, when my own behaviour is in such a state of disarray?
Anyways... Getting pretty long again lol. Hope that response is helpful I know it's a bit rambling.
Like moral imperatives are essential to understanding Kantian Deontology, but the wikipedia article on it goes on a weird tangent about a "Global Economic Moral Imperative," which I have never head of before and is absolutely not something somebody trying to wrap their head around Kantian moral philosophy should be distracted with. I'm kind of annoyed it's even on there, it's absolutely not something Kant ever talked about.
If you want a better highly detailed resource I would recommend the Stanford Encyclopedia of Philosophy at https://plato.stanford.edu
But if that's too much (it is VERY detailed)... I can highly recommend chatGPT. For whatever reason it genuinely excels at philosophy. I've used it to discuss different absurdist philosophers before and it did an excellent job, which surprised me because I find it to be otherwise unreliable for a lot of subjects.
You can ask it to compare and contrast philosophies like Utilitarianism, social contractionism, deontology, etc, and tell it to simplify or summarize things, it is impressive how good it is.
Another approach is, also surprisingly, Youtube!
The channel PBS Crash Course Philosophy is at the level of an introductory philosophy course at a University and has good episodes on concepts like Kant's Categorical Imperatives (a favorite of mine):
https://www.youtube.com/watch?v=8bIys6JoEDw
Also the channel the School of Life has fun little overviews of different philosophers that I can vouch for like this one:
https://www.youtube.com/watch?v=xxrmOHJQRSs
And for longer format documentaries the BBC has great documentaries like this one on Nietzche that are similarly entertaining:
https://www.youtube.com/watch?v=u9f1F5jUzaM
So I would recommend trying these different resources and seeing what combination you like.
For the record, my background is in mathematical logic (first order predicate calculus and all that) but from a computer science, rather than philosophical point of view, so I find the SEoP accessible. I just don't have any background in moral philosophy (except of course that I'm Greek and so grew up with the classics, because you can't avoid that).
