That would get at the core of the absolute vs relative morality debate and I don't think humanity will ever settle on that. It's far more likely that a "Prime Directive"-like non-interference law comes into effect instead. The natural world is cruel but heavily interdependent; as long as we assume that each creature or plant has a right to exist and reproduce, all we can do is eliminate our own effects on ecosystems. Humans are nature's worst transmission vector for pathogens, invasive species, habitat destruction, etc and there's little evidence we'd do anything but make the suffering a lot worse.
Similarly we are foolish to concern ourselves with the quantity of serotonin or histamine in any given creature.
Humans are generally social, we developed to be concerned with our community rather than our individual survival and it has served us well. We developed systems to extend that concern to future generations, and sometimes we disguised them as deities. Now in our ever blooming quest to socialize we are assimilating more species into the fold, but at a point we should stop and ask if our moral tools are overstepping.
Isn't rusting metal just metal that's trying to return to its natural form?
There's a famous phrase about humans being Nature's tool for adding plastics into the world.
1) Life is just a chemical reaction, human sadness / happiness don't matter
2) Humans are fundamentally different than other animals - our pain is somehow more real than animal pain
3) Animal pain does matter.
Personally I favor 3)
Humans are fundamentally different because that's us. And even between humans, there is a scale. To me, the only real pain is mine. But, I also have the ability to feel other people's pain, so the pain of people close to me is also real, but less so, it is indirect. To feel pain for a random human requires some active thinking. The further we go, the less real pain is, simply because our brain can't process and mirror it.
Animals look a bit like us and show similar pain reaction so we can emphasize somehow. But for everything after plants, we are getting too far. And then, we can introduce computers: can an AI feel pain? How advanced does it have to be if it does? Maybe it is all programs. Unit tests must hurt...
But from an ethical perspective, the pain of a random person is just as important, right?
> Animals look a bit like us and show similar pain reaction so we can emphasize somehow. But for everything after plants, we are getting too far.
Animals don't just show similar pain reactions - the biochemical pathways are the exact same. For me, I have to assume basic physical pain is nearly the same, at least for mammals. For plants I don't know. It's possible they have some pain, but I'd expect it to be very different and lesser. For computers I see no reason to think there's any physical pain (though perhaps in the future)
Humans will need to either learn to:
- Terraform the Earth and keep it cool -- this can keep the Earth habitable for maybe 1-2 billion years at most instead of a few hundred million which is the current expectation. After that it will be of no use and the sun will eventually engulf the Earth in ~4 billion
- Not rely on other species or the oceans to survive, and find artificial ways to manufacture food
- Evolve into (i.e. develop) an intelligent but inorganic life form that can withstand higher temperatures and carry on the legacy of intelligent civilization
- Move to Mars or beyond, terraform it, and take animals with us
Considering the complex inter-dependencies of various species (e.g. humans need to eat plants, plants need insects and worms but their numbers are kept in check by birds, birds need huge plants to reproduce, plants also need to eat shit from animals, animals need yet other plants to make said shit, etc.) I have most hope in creating an inorganic lifeform that can reproduce given only light and raw materials available on planets, and without dependence on other life forms.
Terraforming our planet is a megaengineering project in itself. It's not much of a stretch to imagine megaengineering changing the orbit of earth, or increasing the lifespan of our star by collecting the gases for later use.
You should watch Isaac Arthur the youtube channel.