John Finnis has a very simple argument for fetal personhood (in "Abortion and Health Care Ethics," which is reprinted in Bioethics, edited by Kuhse and Singer) -- 
"Any entity which, remaining the same individual, will develop into a paradigmatic instance of a substantial kind already is an instance of that kind. The one-cell human organism originating with the substantial change which occurs upon the penetration of a human ovum by a human sperm typically develops, as one and the same individual, into a paradigmatic instance of the rational bodily person, the human person; in every such case, therefore, it is already an actual instance of the human person."
Making the argument about my own one-cell zygote (call it "Z"), it goes like this--
  1. Z developed into a paradigm case of a human person, i.e. JK, the person writing this post.
  2. Z is the same individual as JK, not a different individual.
  3. Personhood is a substantial (or essential) kind, not an accidental kind - it's a property that an individual can't gain or lose while remaining the very same individual.    THEREFORE,
  4. Z was a person.
Premise 1 is obviously true.  I think I could also go along with premise 2 as well--or at least I'm not violently opposed to it.   What I don't find at all obvious is premise 3.  Adulthood is obviously just an accidental kind--it's gained part way through the career of one and the same individual.  Butterflyhood seems more essential than adulthood, but it's accidental too. It's gained part way through the same lifespan of one individual.

Why not think personhood is just as accidental as butterflyhood?  A butterfly would no doubt be appalled by the suggestion that she -- she -- was once a lowly crawling caterpillar.  I'm not sure there's anything more backing up the essentialness of personhood than the human equivalent of butterfly-pride.


Wayne said...

I agree... Personhood has to be an accidental quality... Say that personhood is not an accidental quality... Z would retain personhood, assumedly, after death, since nothing about the person is significantly different before and after death, then Z would be a person, despite being dead.

If this is a significant change (death) then it would appear that there is something about consciousness or mental life, that is essential to personhood, in which case Z (for zygote) doesn't get personhood.

If its something about it being animate... alive/metabolizing, then it was a person prior to fertilization. But its not... its attached to paradigmaticness... Part of being human, paradigmatically, is death, so assumedly Z is still paradigmatically a human after death.

That of course is nonsense.

Wayne said...

Hmmm.. after re-reading the definition, maybe my objection won't work...

He says it has to be a paragdigmatic case of a rational person, or will be the case...

But I'd attack the will be part... I really don't know if this particular Z will be a paradigmatic case of human rationality. Are mentally handicapped paradigmatic cases of human rationality? Clearly not.

Heck, am I a paradigmatic case of human rationality? arguably not. I'm above the norm (or maybe below the norm). So far from it, it is not yet a paradigmatic case of a rational human.

ɻɵʗɺʍɔʥʅɑɯɒɠʨʂʫɒʡɼʌɒ said...

I see that "typically develops" becomes "in every such case".

So every fertilized egg is paragdimatic of its actual future, (if we suppose some deterministic evolution), rational or handicapped, and the choice to include this paradigm into some class (e.g. the handicapped, the human, the mammal, the vertebrate, the living, ...) is not factual but normative.

Also, I think the separation between the fertilised egg and the environment is quite arbitrary, since any living system exchanges a lot of matter and energy with its environment. I think Parfit could come up with some nice example of some evil scientist replacing cell by cell and asking, "where is the individual?". Personal identity "doesn't matter" probably ...

And also, even if we could prove some identity, we should show that this identity over time is morally relevant ...

it seems to be a pretty weak argument ...

Aeolus said...

"...remaining the same individual", "as one and the same individual" -- This seems to beg the question, unless "individual" is equivalent to "organism", in which case the plausibility of the argument depends on not noticing the slide from "organism" to "person". I think John Locke would have given this a failing grade.

Faust said...

I don't think it goes through. Of course I'm pretty convinced that newborn infants aren't "the same individuals" that they will one day become. So obviously this argument isn't going to be very effective in my case.

Wayne said...

@Faust I'm not sure a person has to be the same individual to have the same properties. Let's just say for the sake of argument that my identity is not the same to the person who I was when I was in my mother's womb (I wouldn't believe this normally).

My fetal self has certain properties that I still have today, like he has arms, and legs, and I have arms and legs. So even if I'm not identical to that person, doesn't mean that some of the properties of that person don't persist through time to today. Arguably my personhood persisted as well as my arms and legs.

Faust said...


When you write "Let's just say for the sake of argument that my identity is not the same to the person who I was when I was in my mother's womb (I wouldn't believe this normally)."

Are you saying that normally you do believe that you have the same "identity" that you did when "you" were in your mothers womb?

If so I'm curious what this "identity" consists in.

To elucidate my own position a bit further I have trouble with/struggle with all of the following:

1. The notion that anything has "intrinsic" worth.

2. I generally find that I don't think anyone has a clear idea what they are talking about when they say "person," "Person" frequently seems to just mean "a living being that has full moral worth," or similar. So to me a sentence like "Personhood is a substantial kind" is similar to saying "A being with full moral worth is a substantial kind." Maybe that is so? But generally I think "person" is not a helpful concept. It doesn't seem to do much work.

3. "Identity" is a concept that is very difficult to cash out. Currently, I'm inclined to agree with Mark Johnston's argument that Identity is "construal dependent" which Jean has elsewhere rejected, though frankly I think she just didn't engage the argument.

Anyway the cruicial question here seems to be:

When do "beings that have full moral worth" aquire their full moral worth? Where does this moral worth come from.

My view is that moral worth is granted by agents, and does not have any other source (is not intrinsic).

In a related note, this whole line of thinking reminds me very much of an old post that Jean put up about the "do you benefit a child by giving them existence even if you immediately give them up/sell them into slavery" question. But I can't find the original post.

Simon Rippon said...

I think you're absolutely right about this argument - and the butterfly/caterpillar analogy is a great choice to illustrate the problem.

I'd describe the flaw as an equivocation on "individual" between the second and third premises (so I'm agreeing with Aeolus). On one reading of "individual" - the "individual entity" reading, your personhood is unnecessary to what makes you an individual. On that reading, premise 2 may is true of a fetus and the paradigm human person it grows into, but premise 3 is false. On a second reading of "individual" - the "individual person" reading, continuity of person is a necessary criterion of identy of an individual over time. On that reading, premise 3 is tautologically true, but premise 2 can only implausibly and question-beggingly be claimed to hold true of a fetus and the paradigm human person it grows into.

Anonymous said...

The things that make up an essence of a human are those things that can't be taken away without destroying its "humanness." I think the are things Z lacks that humans - as far as a general definition goes - requires to maintain it's humanness, especially if it's still a one celled organism (or even a couple hundred cells). If a human characteristic is to be able to communicate, then Z can't fulfill this quality. Breathing air? Being able to sit unassisted for a couple hours? Having bones? Z doesn't have any of these characteristics. Of course, you may want to argue if these even make up the essence of a human, but you'd have to have a pretty lame definition of what makes up a human's humanness for it to include Z.
Can Z become, eventually, all that humanness demands? Sure. And coal can eventual become everything "diamondness" demands. But it's not a diamond. And we'll burn it when convenient.