I’m not really sure what “person” means, other than people, which currently seems to mean the same thing as human beings, members of the human biological species.
If some human beings are not persons, or some nonhuman beings are, then “person” is probably a human socially constructed category rather than a natural or biological kind.
And like all socially constructed categories, it can be modified and extended, as in dubbing temples, mountains or corporations formal “legal persons.”
But as unsure as I am abut what “person” means, I’m sure about what feeling (sentience) means and what a feeling individual, a feeling being is.
And I’m just as sure that nonhuman animals are feeling individuals (sentients) as that other human beings are.
Maybe it will help, somehow, to modify and extend the category “person” to include nonhuman animals. It’s certainly necessary if personhood is a club that it’s necessary to belong to in order to qualify for mercy from human beings.
Or maybe just being a feeling individual is enough, and knowing that feelings can be hurt.
Whatever it takes to stop the horrors.
Broude, Gwen J. (2016) Who is a person? Whoever you want it to be Animal Sentience 2016.112
Harnad, Stevan (2016) Animal sentience: The other-minds problem Animal Sentience 2016.001
Rowlands, Mark (2016) Are animals persons? Animal Sentience 2016.101
Wise, S. M. (2012). Nonhuman rights to personhood. Pace Environmenal Law Review 30, i.