Suppose a dog lives forever. Assuming the dog stays roughly dog-sized, there is only a finite number of possible configurations of the dog’s matter (disregarding insignificant differences on the order of magnitude of a Planck length, say). Then, eventually, all of the dog’s matter configurations will be re-runs, as we will run out of possible new configurations. Whatever the dog is feeling, remembering or doing is something the dog has already felt, remembered or done. It will be literally impossible to teach the dog a new trick (without swelling the dog beyond normal dog size).
But a dog’s life is a material life, unlike perhaps the life of a person. Plausibly, a dog’s mental states are determined by the configuration of the dog’s (brain) matter. So, eventually, every one of the dog’s mental states will be a re-run, too.
And then we will run out of states re-run once, and the dog will only have states that are on their second or later re-run. And so on. There will come a day when whatever the dog is feeling, remembering or doing is something the dog has felt, remembered or done a billion times: and there is still eternity to go.
Moreover, we’re not just talking about momentary re-runs. Eventually, every day of the dog’s life will be an identical re-run of an earlier day of the dog’s life (at least insofar as the dog is concerned: things beyond the power of the dog’s sensory apparatus might change). And then eventually every year of the dog’s life will be a re-run of an earlier year. And then there will come a year when every coming year of the dog’s life will already have been done a billion times already.
This doesn’t strike me as a particularly flourishing life for a dog. Indeed, it strikes me that it would be a more flourishing life for the dog to cut out the nth re-runs, and have the dog’s life come to a peaceful end.
Granted, the dog won’t be bored by the re-runs. In fact, probably the dog won’t know that things are being re-run over and over. In any case, dogs don’t mind repetition. But there is still something grotesque about such a life of re-runs. That’s just not the temporal shape a dog’s life should have, much as a dog shouldn’t be cubical or pyramidal in spatial shape.
If this is right, then considerations of a dog’s well-being do not lead to the desirability of eternal life for the dog. As far as God’s love for dogs goes, we shouldn’t expect God to make the dogs live forever.
This is, of course, the swollen head argument, transposed to dogs, from naturalist accounts of humans.
But maybe God would make dogs live forever because of his love for their human friends, not because of his love for the dogs themselves? Here, I think there is a better case for eternal life for dogs. But I am still sceptical. For the humans would presumably know that from the dog’s point of view, everything is an endless re-run. The dog has already taken a walk that looked and felt just like this one a billion times, and there is an infinite number of walks that look and feel just like this one to the dog ahead. Maybe to the human they feel different: the human can think about new things each time, because naturalism is false of humans, and so differences in human mental states don’t require differences in neural states (or so those of us who believe in an eternal afterlife for humans should say). But to the dog it’s just as before. And know that on the dog’s side it’s just endless repetition would, I think, be disquieting and dissatisfying to us. It seems to me that it is not fitting for a human to be tied down for an eternity of a friendship with a finite being that eventually has nothing new to exhibit in its life.
So, I doubt that God would make dogs live forever because of his love for us, either. And the same goes for other brute animals. So, I don’t think brute animals live forever.
All this neglects Dougherty’s speculative suggestion that in the afterlife animals may be transformed, Narnia-like, so that they become persons. If he’s right, then the naturalistic supervenience assumption will be no more true for the animals than for us, and the repetition argument above against dogs living forever will fail. But the argument above will still show that we shouldn’t expect brute animals to live forever. And I am dubious of the transformation hypothesis, too.
At the same time, I want to note that I think it is not unlikely that there will be brute animals on the New Earth. But if so, I expect they will have finite lifespans. For while an upper temporal limit to the life of a human would be an evil, an upper temporal limit to the life of a brute animal seems perfectly fitting.
