Abstract
Animalism is the doctrine that you and I are animals. Like any substantive philosophical position, animalism faces objections. For example, imagine a case of conjoined twins, where there are two heads, but only one “body,” and where each head seems to have its own typically human and fully discrete mental life. It would be natural to assume that each of the twins is a thing like you and me—each twin is one of us. But it appears that each twin cannot be a distinct human animal, since it appears in this case that there is only one animal. So it appears that animalism renders the wrong verdict in this case. I present two responses to this worry, drawing on Aristotelian claims about the centrality of sensation to animals, and on an account of organism-hood from Maureen and Samuel Condic. I close by considering craniopagus parasiticus and cephalopagus, and show the Aristotelian response is effective in such cases as well.
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Notes
See Tim Campbell and Jeff McMahan, “Animalism and the varieties of conjoined twinning,” in Stephan Blatti and Paul F. Snowdon, eds., Animalism: New essays on persons, animals, and identity (Oxford: Oxford University Press, 2016), 286.
Olson, “The metaphysical implications of conjoined twinning,” Southern Journal of Philosophy 52 Spindel Supplement (2014), 24–40; at 31. This is connected to, but slightly distinct from, another reply Olson offers to the objection, which is that it doesn’t actually introduce a new problem for the animalist: it is not a fundamentally different case from worries about, for example, cerebrum transplants. In a cerebrum transplant case, the cerebrum is removed from living animal P, leaving P alive, and placed in Q—a distinct living animal whose own cerebrum had previously been removed. When the animal Q awakens from this surgery, it thinks it is P: has P’s memories, beliefs, maybe habits, etc. According to the “Transplant Intuition,” we are inclined to say something like this: P is now ‘in’ Q: P ‘went with his consciousness’; or something similar. But the animalist must deny this, for if we are identical to animals, we can hardly be moved from one to another. The twinning argument gets at the same issue from a slightly different angle, but it presents no new problem for the animalist. Thus, Olson thinks, animalism is already committed to the denial of psychological identity conditions for things like us: and the upshot of the twin case, with two distinct centers of consciousness in one animal adds nothing fundamentally different to the discussion.
Of course, there could be a human organism that doesn’t think—a severely brain damaged one, for example, or an extremely young one. What I mean is that it’s unbelievable that the organism involved in typing (or reading) this sentence isn’t thinking.
“Conjoined Twinning and Biological Individuation,” Philosophical Studies 177 (2020), 2395–2415.
I don’t think it’s necessary for me to work through the surveyed material in detail, but roughly put, she divides current scientific opinion into two groups, and then further subdivides those groups. The two main groups are comprised of those views according to which individuation is based on physiological facts, and those views according to which individuation is based on evolutionary facts. The physiological approach focuses on functional integrity: candidates include metabolic and immunological integrity. The evolutionary approach might focus on reproduction, or populations “exhibiting heritable variance in fitness,” or a kind of functionalism. (Boyle, 2402).
Boyle, 2403.
In his 2014 article, Olson wound up in a different spot in cases where the two persons each had a distinct brain stem, for at that time Olson held that the brainstem played a crucial role in the individuation of higher organisms. What Boyle has done through her work on the science of individuation, in part, is to have make an even stronger case for the irrelevance of the brainstem to the discussion.
Boyle, 2412.
Due to a dispute with Olson that isn’t relevant to my purposes here, she also takes herself to have shown that animalists have to accept the reality of these cases. Olson had previously suggested that in real life cases of twinning where there are distinct psychological streams, it would be plausible to claim that in fact there were two organisms present, and he gave the response I dealt with above more or less as a gesture in the direction of addressing mere possibilities rather than actualities. If Boyle is right, then these cases are indeed actualities, so she is also adding that point to the discussion.
“Generic Animalism,” The Journal of Philosophy 118 (2021), 405–429.
Persons, Animals, Ourselves (Oxford: Oxford University Press, 2014), 184.
As I’ve said a couple of times above, I don’t see a need to really delve into the details of the theory here: my purpose in mentioning it is not to either praise or blame it, as much as to simply note it as a possible solution to the problems I’m addressing here. Very briefly, you can see the heart of Bailey and van Elswyk’s move in this formal account of two views. First, Unrestricted Animalism, which translates the English claim “We are human animals” into logical form this way: (∀x)[human-person(x)] [human–animal(x)]. Then, Generic Animalism which (in one version) translates the English claim “We are human animals” into logical form this way: (∀x)[normal-human-person(x)] [human–animal(x)]. (Bailey and van Elswyk, 415) In a different version, the translation is “(GEN x)[human–person(x)][human–animal(x)],” and here of course you can see that they’ve introduced a new quantifier to capture the sense of ‘normal,’ which they explain in great and careful detail.
See, [author’s papers]. “Thomistic” views are worked out by others in ways that of course overlap my way, but also differ from it in ways trivial and profound. For one example of a competing Thomistic view, see Jason Eberl’s The Nature of Human Persons (Notre Dame, IN: University of Notre Dame Press, 2020). Of course, there are hylemorphists who are in no real sense Thomists, and obviously the differences between their views and mine are much greater than in the case of Eberl.
The Basic Works of Aristotle, ed. Richard McKeon (New York: Random House, 1941), 557.
Commentary on Aristotle’s De Anima, Book 2, Lecture 3 (South Bend: Dumb Ox Books, 1994).
In a complete account, there is more to being an animal than merely being a living, sensing thing. For example, they also have sensory appetites, divided into the concupiscible and the irascible. See, for example, Henry J. Koren, An Introduction to the Philosophy of Animate Nature (Piscataway, NJ: editions scholasticae, 2014, repr. of 3rd ed. 1960). More, in cashing out what it is for an animal to be alive, we will find ourselves dealing with a group of characteristics that in many respects resemble criteria discussed by Boyle. On the Aristotelian story, animals, qua living things, include the purely vegetative functions (viz. reproduction, growth, irritability, nutrition). Some of these elements would need to be cashed out very carefully to take into account things like teleology and potentiality—a couple of items I touch on unsatisfactorily later on. Because this paper isn’t meant to be an account of Aristotelian biology, but merely the application of one principal notion from it, and because it is long as it is, I hope I can leave aside serious exegetical work on animals in this tradition.
This may be plausible, you say, in the case of eyes, nose, mouth and ears. But what about the sense of touch? That’s much more distributed. Fusion arguably has its own skin, right? Be that as it may, the ability to engage in tactile sensation isn’t found in the skin, it’s found in that sense organ plus the remaining neurological system, especially the brain: and the brains, like the eyes and ears, etc., belong plausibly primarily to A and B. I think the same could be said for other ‘sensory’ activities such as proprioception.
This objection comes from a referee for this Journal.
To be sure, the Generic Animalist might say something like this: what differentiates the two people in this twinning case from two human persons is that the twins are people that can’t sense, although each twin believes she senses. But given the Aristotelian account of organisms and its ability to yield two persons and two animals in this case, Generic Animalism would be here unmotivated.
Also taken from a referee for this Journal.
For some relevant discussions, see [author’s paper]. The material by the Condics, discussed in the next section of the paper, is also very relevant and while for purposes of this paper I present it as an independent account, it is clear that a full Aristotelian account of organisms will include some notions about finality, such as those defended by the Condics. See also works such as Patrick Lee’s Abortion and Unborn Human Life, 2nd ed. (Washington, DC: Catholic University of America Press, 2010). Fabrizio Amerini’s work is also highly relevant, though I disagree with many of his conclusions and applications. See Aquinas on the Beginning and End of Human Life, trans. Mark Henninger, SJ (Cambridge, MA: Harvard University Press, 2013).
There is a scholarly dispute about whether Aristotle eventually changed his position on this matter and asserted that form is primary substance. I think we can ignore that point: anyway, St. Thomas didn’t, and I’m writing as a Thomist, not as an Aristotle scholar.
Yet another way to think of this objection is to say that of course, in one sense A and B are living things. But are they living things in the right sort of way to allow them to be animals? For any one of my cells is a living thing, but it’s not the right kind of thing to be a human animal, even if it’s a living human…thing.
Boyle, 2401.
“Defining Organisms by Organization,” National Catholic Bioethics Quarterly 5 (2005), 331–353 at 338.
Boyle, 2401.
Condic and Condic (2005), 338.
Condic and Condic (2005), 338–339.
Sameul B. Condic and Maureen L. Condic, Human Embryos, Human Beings (Washington, DC: Catholic University of America Press, 2018), 178. One might add to this, taking into account the thought in the previous long quotation, that even if the being is not actually capable of reasoning when the developmental process is complete, it might still be a human being, given that this failure in its ability to reason nevertheless occurs in a developmental process that is in other respects distinctively human, so that the failure to reason might be explained by the child’s failure to grow a normal brain.
You might say that putting it this way begs the question against Olson, who would say instead that distinct patterns of reasoning are realized in distinct brains spatially located in the heads of “A” and “B,” but this does not imply that there are distinct persons, A and B, doing the reasoning. But this response misses the point, given where we are in the argument. I’m not rebutting Olson’s rebuttal to the objection. I’m criticizing Boyle’s response to it. Boyle has argued that on any current biological account of organism-hood, Fusion is an animal, and A and B are not. That is the contention here, and the contention is being urged as part of a defense of animalism against the commonsense objection noted in the introduction to this paper. For her, a great part of the force of the argument that A and B aren’t people like us lies in having established independently that they’re not organisms. And I’m saying she hasn’t done that: in doing so, I am accepting, to be sure, the appearance—obvious enough!—that A thinks, and that B thinks. If that weren’t obvious, the objection prompting this paper would have no force.
Boyle, 2405.
Boyle, 2405.
And their track record when they take on this question is pretty poor. See, for example, Edwin Black, War Against the Weak, 2nd ed. (Washington, DC: Dialog Press, 2012).
Boyle, 2411.
The case comes from his Material Beings (Ithaca, NY: Cornell University Press, 1990), 59.
Of course, there are replies to this: for example, she might say that we should rely on intuitions unless we have a good scientific reason not to. I don’t claim this is a knock down argument.
Campbell and McMahon, 291.
If the ‘parasitic’ head lacks a mental life, we lose the force of the objection. If we’re supposing, that is, that the extra had is just an appendage that looks like a head, but doesn’t do any thinking or sensing—that has no self-awareness and so forth—then we’re not troubled, as animalists, by any objections from the existence of such a head.
See, for example, his “The Role of the Brainstem in Personal Identity,” in Andreas Blank, ed., Animals. (Munich: Philosophia Verlag), 2016. Boyle also gives several reasons why the brainstem issue is irrelevant to the case. See 2398-2399; 2406.
Campbell and McMahon, 298. This is an imagined case, but with roots in reality. We could imagine cases somewhat like this where it was not at all clear to us as outsiders whether there was any mentality present at all, or whether there was one sensory life, or whether there were two sensory lives. And this brings us back to a point I made earlier: the solution here is a metaphysical one, not an epistemological one. Perhaps the most we can say in some cases is that if there is one living sensing thing here, then there is one animal here; but we can’t use that knowledge to actually count the animals present. This I regard as inescapable, but not as a problem for the account.
Many thanks to two anonymous reviewers for this Journal, and to members of the Wake Forest Philosophy Department for very helpful questions and comments.
References
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Toner, P. Hylemorphic animalism and conjoined twins. Philos Stud 181, 205–222 (2024). https://doi.org/10.1007/s11098-023-02060-z
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DOI: https://doi.org/10.1007/s11098-023-02060-z