Friday, October 30, 2020

Slippery In-Between Persons: Growing, Fading, Merging, Splitting

Philosophers normally treat personhood as all-or-nothing. An entity either is a person or is not a person. There are no half-persons, and no one has more personhood than anyone else. We usually don't think much about vague or in-between cases.

One exception is the literature on so-called "marginal cases" -- humans with severe disabilities, for example, or entities in the slow progression from fertilized egg to self-aware toddler, who either wholly or partially lack features that philosophers sometimes regard as essential to personhood.

The literature on personal identity offers other exceptions -- classically in Derek Parfit's wild thought experiments in Reasons and Persons and recently in Luke Roelofs' Combining Minds. "Split brain" callosotomy patients are another interesting case, as are craniopagus twins.

[P.T. Selbit, in an early attempt at person splitting]

The latter cases, though less common (and often purely hypothetical), present a deeper challenge to our notion of personhood than the former cases. The difference between one and two persons is more difficult to manage, conceptually and socially, than the difference between zero and one, which can be handled partly through extending our ordinary thinking about ordinary persons to a range of "marginal" cases, with some tweaks or reductions.

I won't press that point here. What I want to note instead is this: On almost all notions of personhood, we think of personhood as coming in discrete countable numbers -- zero, one, two, etc. -- not 1/8 or 2.4. At the same time, on most accounts of personhood, personhood is grounded in smoothly gradable phenomena, such as cognitive and emotional capacities, social role, and the history of or potentiality for these.

Thus we can in general constuct a gradual series from cases in which we have, clearly, a single person, down to zero or up to two, forcing a theoretical trilemma. In general form:

(1.) Case 1: an ordinary human being who no one would reasonably doubt counts as one person.

(2.) Case n: an entity that is either clearly not a person (the zero case) or a situation in which there clearly are two distinct people (the two case).

(3.) A series of arbitrarily slow and finely-graded steps between 1 and n.

The zero case is tricky if we want to use real-life examples, given that some philosophers would want to describe as persons both a fertilized egg and someone in an irreverisble comatose state due to extreme brain damage. Rather than entering those fights, we can use science fiction: Imagine removing cells from a person's body, one at a time, while keeping the body alive, until eventually only a single neuron remains.

For the two case, we might imagine slowly budding one brain off of another, or we might imagine two people whose brains are slowly interconnected eventually becoming an entity operating as a single person with a single stream of conscious experience.

Imagine, then, such gradual series between 1 and 0 or between 1 and 2. Here's the trilemma.

Option 1: A discrete jump. You might argue that despite the slow series of changes, there will always be a sharp threshold at which personhood vanishes, arrives, merges, or splits. Despite continuity in the grounding properties of personhood, personhood itself remains discrete. Removing a single cell might cause a metaphysical saltation from personhood to nonpersonhood. Adding a single connection between two slowly merging brains might cause a metaphysical saltation from two people to one.

Option 2: Gradations of personhood. At some point between zero and one, you have a kind-of person. More radically, at some point between one and two, you have... what, a person and a half?

Option 3: Conceptual collapse. Some concepts have false presuppositions built into them and should be rejected entirely (e.g., exorcism, the luminiferous ether). Other concepts are okay for a limited range of cases but fail to apply, either yes-or-no, to other cases (e.g., primeness to things that aren't numbers). Maybe personhood is such a concept -- a concept built exclusively for ordinary countable-persons situations.

Option 1 strikes me as implausible. (Admittedly, some people are more willing than I to see sudden metaphysical saltations in gradual continua.)

On Option 3, we might eventually need to retire the concept of personhood. Maybe -- far-fetched science fiction, but not impossible -- the world will eventually be populated with intelligent AI or biological systems that can divide or merge at will (fission/fusion monsters). Our concept of personhood, if it's inherently and unchangeably committed to discrete countability, might end up looking like the quaint, unworkable relic of old days in which brains were inevitably confined to single bodies.

On Option 2, we face the task of modifying personhood into a gradable concept. I worry about the implications for our thinking about disability if we rush to do that too quickly for the zero case; but the one-to-two case is intriguing and insufficiently explored.

[image source]


Mike Almeida said...

The properties n&s for personhood-at least on a Lockean account-are all vague. So you do get vague or indeterminate persons and, worse, indeterminate rights(an indeterminate right to life, for instance. There are a few papers on this issue.

Eric Schwitzgebel said...

Right! The "marginal cases" literature, for example. It has been less explored for the one-to-two case than for the zero-to-one case. I'd be grateful for pointers on that, if you know any.

Eric Schwitzgebel said...

I already know this one (Briggs and Nolan 2015):

Arnold said...

Wouldn't this also apply to gradations of philosophical persons...progressing to...

...progress, progressive, progression, progressing...different meanings at different times?

SelfAwarePatterns said...

In terms of natural kinds, I think Option 3 will eventually be the reality. This isn't unusual. Nature has never cared about our little categories.

But that doesn't mean we might not preserve the concept as a matter of convention, one that all us persons would have an interest in preserving. Just as society has a lot of rules about human procreation, if we had the ability to split, merge, or duplicate ourselves, I'm sure a whole bunch of new rules would eventually be developed to deal with things like the effects on property rights and other legal relationships, not to mention the ethical implications.

Of course, just because society sets up such rules doesn't mean everyone will follow them.
A scary scenario might be criminals, person predators, who copy others or merge with them without their consent. People might have to protect their identity in a much more primal way than they do today.

Luke Roelofs said...

I think it’s useful here to think about why our concepts are the way they are, and I’d suggest that one reason is that persons are self-counting. They don’t just *have* certain cognitive capacities, they use those capacities to organise their thoughts and behaviour into a coherent ‘self-that-is-aware-of-itself’. At least, the ones that grow up in our societies do (maybe partly because we encourage them to?).

That makes me think that when we’re dealing with these intermediate cases that might be confusing or complex, the first principle to follow would be to try and defer to the person(s) themselves - within the ‘system’ (to put it as neutrally as possible), is there a single coherent self-awareness forming, or two, or none (or something else)? That’s not a simple principle to apply (think of the difficulties of detecting self-awareness in animals, for instance, or of defining what it is we’re trying to detect), but I like the idea of an orientation that would start by trying to listen to what we’re being told by the system, even when we have trouble making that out.

Of course that would still break down in cases where there is, within the system, conflicting or incoherent patterns of self-awareness - as well as in cases where we think of ourselves as dealing with an incipient person(s), possessed of the potential to identify itself or themselves but not yet actualising that potential. Something like option 3 - conceptual collapse - seems like the right position here, but I think it’s somewhat noteworthy that this isn’t simply a situation where ‘we’ are trying to apply a concept to some difficult phenomenon outside its usual parameters, and the concept breaks down. Rather, it's be a case where ‘we’ are trying to cooperatively apply the concept together with the phenomenon itself (i.e. it’s among the ‘us’), and finding that it breaks down. I think that fact somewhat shifts how we would (or will) go about trying to rebuild or extend the concept, though it doesn’t do too much to actually tell us how to proceed.

Ryan Clark said...

What if we replace the word "person" with a word that I think is equivalent but much more to-the-point: "experiencer"?

If we make this replacement, it seems to become intuitively clearer that it's nonsensical to talk about "half an experiencer" or "2.5937 experiencers". It seems like talking about "experiencers" in anything but discrete integer terms does violence to the very concept of "having an experience" (i.e. subjective, first-person experience -- is there truly any other kind?).

Is part of the problem here, perhaps, that the word "person" simply carries too much baggage, and is too vague and imprecise? I think "experiencer" is much clearer and gets right to the point. I wonder why it doesn't seem to get used much in the philosophy of mind.

Any thoughts anyone?

Philosopher Eric said...

I think you’re on to something with that Ryan, except the reason they don’t use a classification as broad as “experiencer” seems to be because the “person” term is meant to reference a human experiencer. We don’t consider cats “persons” for example, even if they do experience their existences. I guess they’re allowed to inherent money, though only “persons” are legally suitable for marriage with us for example.

Regardless if we go with “human experiencer” then there should only be discrete experiencers as you suggest. This is to say zero, one, two, and so on. Of course we could define a given human experiencer to be less than a full person given various disabilities, or perhaps legal status (like slaves?), but that’s arbitrary.

My favorite funky case on the matter is the conjoined craniopagus Hogan twins, still alive up in Canada. The cool thing about them is that they share a Thalamus by which each are able to directly experience the qualia of the other to some degree. Still it does seem that they’re two separate human experiencers who simply have this partial ability to share their qualia with each other. And why might this be the worlds only case where one person is able to directly experience the qualia of someone else? The shared Thalamus link makes this a strong case against substance dualist accounts of mind.

Simon said...

I come at it from a different direction but a quick question, can an ontological status like personhood change while reasonable grounds for continuing identity is conserved?

Arnold said...

Are philosophical treatments of personhood today...infinitism...

But without grounded and progressive attitudes, towards the necessity and certainty of a self...

Then into the infinite we go...

Eric Schwitzgebel said...

Thanks so much for the continuing comments, folks!

Luke: Yes, I like adding that approach to the mix. As you note, it doesn't end up avoiding the problem and might even make it more stubborn.

Ryan & Eric: Yes, it does seem especially strange for the case of persons and human experiencers. Craniopagus twins are a fascinating case. I wish we knew more about what they experienced and how they interacted, but for understandable reasons scientific study of them is limited.

Simon: I'm inclined to think so as long as the "identity" in question isn't personal identity but rather something like identity as a biological organism or as a physical object. (I'm inclined to think that identity is always relative to a sortal, or something like that. The same lump of clay can become different statues, for example.)

chinaphil said...

You've written this as though it's a question about the world, and what things in the world count as persons. But of course that can be inverted, and your question can be restated as something like: To which contiguous group/range of things in the world, can the word "person" be felicitously applied?
Which is fine, and a nice analytical way of approaching things, but... I don't think words work like that. You're no longer doing natural language philosophy.
To make an analogy, we all know what a banana is. I have no doubt that under EU regulations (because there are EU regulations for everything), there is some rule about how bent a fruit can be if it is still to count as a banana under the law. Which is fine, but it's got nothing to do with the meaning of the word banana. It's part of a separate enterprise, the enterprise of regulating commerce. Regulating commerce demands that a category must exist for every possible tradable item, and every tradable item must be assigned to a category. Whereas a natural language demands no such thing.
Similarly, you can create continuous or discrete scales of personhood. But those scales will only ever have a distaff relationship to the concept of personhood in the English language (as it exists in 2020), I suggest. Because our concept of personhood is based firmly in a world where only single persons exist, except in very tiny handfuls of exceptions that have not yet significantly influenced the concept.
All of which tortuous prelude is to get to this point: so your continuous or discrete scale cannot be grounded in natural language. In order to create it effectively, you have to base it on something else. There would need to be a purpose or use or some other grounding for this scale.
Medical ethics could definitely prove to be such a grounding, and there's a sense in which it already works that way, in the consensus that medical professionals have built around terminations of foetuses and cessation of treatment for those with unrecoverable illnesses. But in both cases, as yet, only binary distinctions between 0 and 1 persons have been made. Xenobiology could/will be another potential grounding.
I'm now rereading your post, and I increasingly think that I've recreated it, rather than responded to it! I've essentially come to the conclusion that you refer to as: "Maybe personhood is such a concept -- a concept built exclusively for ordinary countable-persons situations...might end up looking like the quaint, unworkable relic of old days in which brains were inevitably confined to single bodies." So, yep, I agree with that option!

Eric Schwitzgebel said...

Thanks for that thoughtful comment, Chinaphil. Yes, I mostly agree with what you say there. Our ordinary language concept is probably not suited to handle such possibilities, and so if we're going to face them, we'll probably have to tweak the concept in a way that goes beyond ordinary language, probably grounded partly in scientific and ethical criteria.

Arnold said...

Ok you guys, please isn't physiological and ontological interaction what we want...
... in front of a/my person working for personhood (in general)...

My question, that personhood is a struggle in ethics and effort too...thanks