How the Categorical Imperative Entails that we cannot Treat Animals as Means Only

‘Perhaps one may object that they could will a maxim which was limited to non-rational sentient beings. But then you have the usual problems with infants, the mentally infirm, and senile senior citizens. Perhaps we could limit it to non-human sentient beings? But this is to make an exception to a universal rule, which is the very indication that one is acting contrary to the Categorical Imperative!’

This is exactly what I would do — it seems to me that since sentience ≠ rationality (or rational capability, if you like), sentient beings which are nonrational are not owed consideration under the categorical imperative. I’m perfectly prepared to accept the implication that the mentally infirm, senile, or undeveloped are not to be considered ‘persons’ for the purposes of Kantian ethics under this interpretation.

I think that this agrees with the intuitions of many, and with the American legal tradition, in that we often limit the rights, which would otherwise be considered universal or guaranteed, of children (no right to vote, no rights to certain forms of self-determination as in the signing of a contract), the elderly, and the mentally handicapped (also cannot give consent in certain situations), etc. It doesn’t mean that these individuals get *no* moral consideration, but it seems to me that the rights owed to some creature cannot be determined by the mere fact of a simple notion of personhood. I would argue that instead, the many, particular rights we often associate with personhood (‘human rights’) are really owed individually to specific elements of the definition of the notion of personhood. For example, the obligation to avoid hurting one another is owed to the *specific* property of the capacity for pain, and *not* to personhood. (We have a separate obligation not to ‘damage’ one another based upon the fact that it impairs our autonomous functioning, so an action like stabbing someone is wrong for two reasons, and so it remains wrong even if you first anaesthetize your victim.)

So to me, the notion of personhood as a primitive property which earns us various moral rights seems only to confuse the issue, even under a Kantian view. A compromise of one’s rationality constitutes a compromise of one’s personhood. And though I’d rather avoid the usage of a concept of personhood at all, I think it’s still salvageable if we accept the fact that it makes sense that one individual can be more completely a ‘person’ than another, and owed more, less, or different moral considerations on that basis.

This would have implications for your human analogy argument against eating meat. To me, as your brain function declines, you are actually to be considered less a person. When you are totally dead, your personhood is entirely gone, and eating your corpse is only using a non-person as a means to an end. I don’t think cannibalism is wrong, but just icky. I feel that similarly, you’ve only really argued for the ickiness of eating meat, not the wrongness of it.

I agree that we can’t make any special moral exceptions for human beings on the grounds of our DNA. But I believe that without being speciesists, we can recognize a need to treat animals differently from ourselves (and from each other!) for the same reason that we treat them differently from plants. We owe a gorilla less moral consideration than we owe a human, but naturally we owe it much more than we would a Harmonium in the caves of Mercury, even as we might likewise owe a Harmonium a bit more moral consideration than a potted fern.