At the end of the day, it's not about our diet. It's about the fact that non-human animals are individuals, too, who want to live. The same things that give humans intrinsic dignity also apply to other animals with brains and nervous systems.
I would like to find some other way of referring to them besides "non-human" animals... humans are animals, too, so it's logical. But if we've seen other ideas, please let me know. I want to decentralize the human and not collectivize everyone else.
It's less about "veganism" and who is "vegan" and more about... are we recognizing animals' intrinsic dignity and will to live, and are we willing to take steps to put that into action.
Centering their lives, not our own comforts and desires. Because we're capable of the added reflection, we have this moral duty to use such knowledge and put it into practice. If we don't, we're wasting this faculty.