Dave Munger contemplates limits of animal personhood:
So while many animals display remarkable cognitive abilities, there are clearly limits to what they can do. Does this mean they aren’t entitled to be considered “non-human persons?” Is it even appropriate to judge non-human animals in such anthropomorphic terms? Suppose we decide it’s wrong to keep an orca in captivity because of its intelligence. Then what about a slightly less-intelligent animal like a pig or a dog? Where do you draw the line?
Henry Karlson tackles the question from a religious perspective:
What has been suggested by Lewis is that we can have a positive influence in the development of animal personality, and that this role was one we were expected to have from the beginning. ...This positive role we can have in the lives of animals presents to us one example of what it means to be mediators of God’s grace to animals.
It does not have to be the only way our mediatorship can be understood, but rather, it presents the simplest way in which we can see that we possess such a role. It helps us understand that we do have an effect on animals and that we can help them find their own perfection. The happiness we find in this accomplishment indicates that this is indeed a part of our own moral role in the world. But this means, as said above, that there are all kinds of considerations which must be examined. If we understand ourselves as having a priestly role to nature, then we can see, as Lewis did, that abuse of nature, of animals, is sacrilegious. This is why we must be careful it is both a great ability but also a great responsibility placed upon us.
(Video hat tip: Waking Up Now)