Since human beings are also just animals, I assume you have some non-arbitrary reason for favoring one species over another?
Keep in mind that speciation is technically arbitrary, and that we can just as easily decide that you and I are not the same species. Go ahead, explain to me why I’m entitled to farm and eat you. I can’t wait to hear this.
“Murder” is an illegal killing. I don’t oppose murder; I oppose immoral killing. That’s different.
If you simply claimed that you’re against pointless killing I wouldn’t consider that arbitrary, since I share your strong intuition that causing meaningless suffering is deeply wrong. That is, in fact, precisely why I find it confusing that you would violate this intuition.
An arbitrary moral distinction would be like claiming that you are against ending innocent lives, unless they’re a different race, gender, species, nationality, or color than you, given that none of these factors have any moral relevance.
What is the moral significance of a creature’s nationality or species? Moral philosophers consider this question fairly settled, so let me know if you have some novel insights.
If you simply claimed that you’re against pointless killing I wouldn’t consider that arbitrary, since I share your strong intuition that causing meaningless suffering is deeply wrong. That is, in fact, precisely why I find it confusing that you would violate this intuition.
And that is where you will find your answer, I have a personal intuition both about what lives I value- I don't believe all pointless killing is bad, regardless of life form, I don't care if someone pulls up the plants in their yard because they feel like it. And you clearly value some life less than human life given that you eat to exist.
An arbitrary moral distinction would be like claiming that you are against ending innocent lives, unless they’re a different race, gender, species, nationality, or color than you, given that none of these factors have any moral relevance.
What? You understand an intuitive belief can exist for all of those things right?
What is the moral significance of a creature’s nationality or species?
Pretty obvious, I care about the lives of some species and not others. (Do you take antibiotics?). It is based on some framework, that is ultimately based on intuition as well.
In the example you gave, the plant killing wasn’t “pointless” (meaning unjustified). If a person is pulling up weeds because they like how things look without the weeds, that’s potentially justifiable.
A reason is a fact that counts in favor of some belief or course of action. The reason that you like something could be such a fact. But the reason that it might cause suffering or end an innocent life would be a countervailing fact. Human beings are capable of rational judgement. We do this all the time in science, and we have to assume that our judgements aren’t arbitrary, or we descend into nihilism, which would undermine your capacity even for logic (whose axiomatic structure is also based on intuitions).
This is why nihilism is not a position any serious philosopher defends. It’s self undermining. You would need to reason your way to the conclusion that nihilism is true in order to conclude that reasoning is impossible.
You understand an intuitive belief can exist for all of those things right? (Nationality, race, speciation.)
The meaning of the word “intuition” in philosophy is a bit different. It’s an intellectual given, part of a web of belief that would ideally be free of contradictions. Your belief that 1+1=2 is an intuition.
We don’t think of people as having an “intellectual given” that being a different nationality is morally relevant. We think of them as having a bias (or a prejudice), because the whole concept of a nationality is made up, and any intellectual examination of nationalism will reveal it’s not an intellectually coherent category.
Even if it were, it would be a very weak intuition, because the whole concept of nationality is made up. Race and speciation are like that. We made up these categories out of convenience and they have no real meaning.
Suffering is not made up. The goodness of life is not made up. How do I know that? Because I have suffered and I have lived. I am in direct contact with these phenomena.