Nobody is saying that fish are moral agents that can empathise with other beings. That doesn’t man that they’re not moral subjects; the ability to understand that one is causing harm is not a prerequisite for the ability to suffer oneself. I think everyone knows this intuitively, but it does feel good to have our less moral habits be justified by memes that we would otherwise find to be illogical.
By eating vegetables you are doing harm anyway, they are living organisms after all.
Even if we grant that plant “pain” is 100% morally equivalent to the pain of other beings (it isn’t, and you don’t earnestly believe that), we still have to eat them as a matter of biology, since humans aren’t producers and must consume nutrients from other life. It’s the same reason we can’t pass moral judgment on a carnivore like a lion for eating a Zebra.
Morality depends on culture, what is wright in one culture is wrong in another. This is easy to see and pretty obvious, unless that you are some kind of supremacist that thinks that your beliefs are the only valid. If your problem is pain you can kill the animal with one shot in the head and it will be painless, some farmers do this in order to avoid suffering.
I am curious. Do you believe that humans has always had the option to not eat animals?
What I am asking is, is there some point during the evolution of homo sapience where it shifted from being morally acceptable to being morally wrong to eat other animals?
Common mistake, but plants are not moral subjects. If you harm any animal, even an insect, it will respond in ways that you or I would; fleeing, retaliating, or generally just panicking. I think you already understand that plants do not (although they do have biochemical adaptations to sense and respond to stress).
You are right, but I believe putting a cease to life is not inherently bad. If we could kill animals without letting them feel anything, that wouldn’t really be bad.
Ethical consideration has to extend to more than just painless death to be worth a damn. I can’t walk into an infant ward and painlessly murder infants in their sleep for a reason.
This is why we should be killing pigs with nitrogen, rather than CO2. CO2 is how a mammal determines it is suffocating, meanwhile the air is mostly made up of nitrogen so we ignore it. However, it’s precisely this which makes it dangerous to humans working nearby (also the fact that CO2 is heavier than air so you can have open pits), and it’s ruled too expensive to do it humanely.
