Reconciling Humani Generis with the human genetic data showing that there never were just two first parents

[Freddy]

Freddy:

The only argument would seem to be your claim that one generation could show all the characteristics of rationality but they wouldn’t really be rationality as they didn’t have an immortal soul.

I would agree that if an animal shows all the characteristics of rationality, including a speculative intellect, then that animal has a rational soul, which is immortal because of the incorruptible nature of intellect per se.

Wouldn’t you agree that in the grand scheme of things a parent would show a degree of rational behaviour indistinguishable from its child. Or indeed, if the difference was meaningfull in any way that the parent could be more rational than the child. Surely the parent being but one step away from being fully human also had the potential to be rational?

Else you are arguing for this bright line between human and non human which we know doesn’t exist. And which Aquinas was unaware of.

Do you honestly think that if you could go back in time and explain to him that there is no dividing line between us an other animals, that we weren’t always human, that our rationality gradually evolved, then he wouldn’t have changed his arguments?

 

[otjm]

I plead ignorance; the last I read (and some time ago) indicated that through mitochondria, we trace back to one mother.

Has that been disproved?

 

[Neithan]

Else you are arguing for this bright line between human and non human which we know doesn’t exist. And which Aquinas was unaware of.

We don’t know that, and I do think there is a bright line that must have happened in one generation: one generation that we can point at and say, they are behaviorally modern. Recursive language, for example, would be a bright line. The “Romulus and Remus” hypothesis published last year is one possible scenario for how it appeared. I noted earlier that the distinction is between the biological species and behaviour, or between anatomical morphology and neurocognitive function.

 

[Wesrock]

I plead ignorance; the last I read (and some time ago) indicated that through mitochondria, we trace back to one mother.

Has that been disproved?

We can, but the most recent common ancestor is just that: the most recent. It doesn’t mean the first. I don’t necessarily take the most literal-history reading of Genesis, but even the Bible provides an example of this, as rossum pointed out. Adam was the first man, but more recent common male ancestor than Adam is Noah.

Now, in Noah’s case the human population is depicted as bottlenecking to just his family. However, a most recent common male or female ancestor doesn’t require that type of population bottleneck to happen.

You mentioned mitochondrial DNA, which is actually passed down by the mother. For the paternal line (my examples were all male) they look at the Y chromosome. The same logic applies for each, though.

 

[Wesrock]

Neithan:

Freddy:

The only argument would seem to be your claim that one generation could show all the characteristics of rationality but they wouldn’t really be rationality as they didn’t have an immortal soul.

I would agree that if an animal shows all the characteristics of rationality, including a speculative intellect, then that animal has a rational soul, which is immortal because of the incorruptible nature of intellect per se.

Wouldn’t you agree that in the grand scheme of things a parent would show a degree of rational behaviour indistinguishable from its child. Or indeed, if the difference was meaningfull in any way that the parent could be more rational than the child. Surely the parent being but one step away from being fully human also had the potential to be rational?

Else you are arguing for this bright line between human and non human which we know doesn’t exist. And which Aquinas was unaware of.

Do you honestly think that if you could go back in time and explain to him that there is no dividing line between us an other animals, that we weren’t always human, that our rationality gradually evolved, then he wouldn’t have changed his arguments?

Well, we haven’t proved that rationality is simply a more complex version of what animals do, and Aristotleans and Thomists today still reject that. It’s a distinct power (refering to a abstracting the universal forms of things from the conditions of matter) not reducible to just adding more connections between neurons.

 

[Neithan]

Let’s say for the sake of argument that we explore other planets and find organic life there: how would we know if it is rational? [If this is way too far out for this thread, feel free to ignore this post.]

 

[Allyson]

I plead ignorance; the last I read (and some time ago) indicated that through mitochondria, we trace back to one mother.

Has that been disproved?

Just to add to @Wesrock said, the last common male ancestor based on the Y-Chromosome lived 180K before the last common female ancestor. Although there is no good reason to expect them to the MRCA to be Adam and Eve in any sense, it is helpful to see just how complex the genetic data is. My attempt to head off that line of thinking at the beginning of the thread went down a side road in the subsequent responses. I know that some people do think that it is somehow proof for Genesis, much to the chagrin of my Anthropology professors.

 

[Neithan]

Correct me if I’m wrong, but Adam (biblical Adam, not Y-chromosome Adam) does not need to be a patrilinear MRCA. Our MRCA is unknown and could be as recent as a few hundred years before Christ.

 

[Gorgias]

Aquinas refers to Aristotle to say that powers of the soul that are not rooted in the senses are what distinguishes the human soul from the animal.

That it “distinguishes” the two doesn’t imply that it “causes” the soul.

So there is the question of how a regular soul turns into an immortal soul. Thomism doesn’t address that, no?

It’s the direct, unmediated action of God.

In my view it simply doesn’t matter what we think is a rational enough hominid to be granted immortal status to their soul. It was God’s decision to decide at what point we were rational enough to be granted the grace to reciprocate love back to God.

I think that’s backward – ‘rationality’ doesn’t cause the soul, nor have we any inkling in God’s revelation that this is how it happens.

You can’t therefore claim that characteristics that could have been evidence for rational behaviour can therefore claim that they are once the rational animal posesses one.

Isn’t that precisely what you’ve attempted to do in these threads, though? Claim that behavior in animals that has the appearance of rationality when applied to humans is a claim for rationality in animals?

It doesn’t BECOME rational when given an immortal soul as that it implies that it was given rationality at the same time .

Just for the sake of argument: why is this not the case, or even reasonable to argue?

And in any case, how on earth could characteristics be associated with rationality and not actually be rationality itself?

As I’ve said, over and again: by invalidly extrapolating from observation to conclusion.

It seems you can change the definitions of things depending on your viewpoint.

Pot, meet kettle?

We grant that an embryo has a soul because it is potentially a rational animal

No: we grant that an embryo has a soul because it’s human. In particular, because as a human, it receives an immortal soul immediately from God.

 

[Allyson]

Correct me if I’m wrong, but Adam (biblical Adam, not Y-chromosome Adam) does not need to be a patrilinear MRCA. Our MRCA is unknown and could be as recent as a few hundred years before Christ.

I am with you on the first sentence and have no disagreement. I am confused on the second sentence. Could you elucidate?

 

[Allyson]

This is why I disagree with @Allyson’s suggestion that “if the soul is having an effect on the evolution of the genome, that is a testable hypothesis.” We do not have a precise enough definition of the soul to tell if it is the soul affecting the genome or the genome affecting the soul.

You stated the following:

On another issue, I would count the rational soul as exterior to the genome, though the genome has adapted to it. Any genetic changes are after the soul, by natural selection to improve our use of our rationality.

You implied a spiritual cause on material reality, which we should be able to test for by looking for extraordinary effects not expected based just on natural causes. If you cannot eliminate natural causes, then why in heck does the Church claim to test to verify miracles and private visions. It can’t just be a racket to make money???

 

[Neithan]

Our most recent common ancestor is someone who all living humans today can trace our genealogy back to, and they would be significantly more recent than either our matrilinear or patrilinear MRCA, which are both quite strict criteria. The 300 BCE number is some conjecture I read by mathematicians Douglas Rhode, Steve Olson and Joseph Chang, published about 15 years ago [you’ve probably seen it before somewhere]. Biblical Adam certainly didn’t live that recently, but he could be much nearer to us in time than his Y-chromosome ancestor. Adam and Eve as a pair of MRCAs could be as recently as 3,000 BCE if I understand this correctly.

 

[Allyson]

Let’s say for the sake of argument that we explore other planets and find organic life there: how would we know if it is rational? [If this is way too far out for this thread, feel free to ignore this post.]

I like this thought experiment, and I do not think it is too far outside this thread. I am going to think on it a it a bit, but just to tie back to what you and @Freddy have been discussing, I have couple thoughts.

First, assuming for the sake of argument that God ensouled just two true humans, Adam and Eve, and they propogated their spiritual gift to everyone now on earth (some how - I have downloaded the article you linked to to review ), there is still the issues of them sharing a culture were other humans who are like them in every other respect. We are used to a fast pace of change in technology, but even with the changes, most people have kept up year to year. How is it reasonable that their descendents would continue to share culture with their contemporaries if the rationality of the soul is a bright line?

I don’t think I articulated that thought very well, because I have some other thoughts going on at the same time. I am going to take a look at that article and see if I can iron out my other thoughts.

 

[Allyson]

I think the link just gave me the first page (working from a tablet), but either way I looked up the authors and I do remember that idea, although it is quite old in science years. It was published well before we had ancient genomes to study. It seems that they are focused specifically on the ancestor that you last share genetic material with, and in so far as that goes, it makes sense. I am not clear on why is should make an Adam closer in time to us.

 

[Neithan]

I am not clear on why is should make an Adam closer in time to us.

Maybe we’re defining “Adam” different? What Rhode et al. call the IA point, or identical ancestors of all living humans today, would be much more recent than either our patrilinear (Y-chromosome) or matrilinear (mtDNA) most-recent-common-ancestor (which actually set an earliest possible MRCA, whichever is oldest). Biblical Adam and Eve, if they lived at the same time, could be IAs before populations became isolated anywhere (conjecturably about 10,000 years ago) without being either our patrilinear or matrilinear MRCA, respectively.

How is it reasonable that their descendents would continue to share culture with their contemporaries if the rationality of the soul is a bright line?

Could you illustrate this? I’m not sure what you mean. Dr. Vyshedskiy hypothesizes the most articulate individuals of a hominin group would be the leader, and when those with recursive language appeared they would have become the leaders, which could explain why they had preferential mating and spread their genes quickly.

 

[Allyson]

Maybe we’re defining “Adam” different? What Rhode et al. call the IA point, or identical ancestors of all living humans today, would be much more recent than either our patrilinear (Y-chromosome) or matrilinear (mtDNA) most-recent-common-ancestor (which actually set an earliest possible MRCA, whichever is oldest). Biblical Adam and Eve, if they lived at the same time, could be IAs before populations became isolated anywhere (conjecturably about 10,000 years ago) without being either our patrilinear or matrilinear MRCA, respectively.

Okay, just to frame the discussion. When I am speaking of Adam and Eve I mean what Pius XII meant. That there were two first parents from whom all men and women now living have received through generation a fallen rational and immortal soul. (I am granting that there was no genetic bottleneck of just two people to make it work for the sake of this part of the discussion.)

So are you saying, that the first two people on the history of the human genus to have immortal souls lived 10,000 years ago?

I don’t necessarily have a requirement that they be the MRCA of the whole extant genome, so if that is what is tripping you up, we can leave that aside. However, if the claim is that every human alive received their fallen nature from Adam and Eve’s choice, then they have to have existed far enough back in time to make it biologically possible that every human alive by, say, the time of Christ had a rational soul by this process. Otherwise the great commission is a fool’s errand because not everyone had a soul to save.

Could you illustrate this? I’m not sure what you mean. Dr. Vyshedskiy hypothesizes the most articulate individuals of a hominin group would be the leader, and when those with recursive language appeared they would have become the leaders, which could explain why they had preferential mating and spread their genes quickly.

Once we establish a common starting point for the time line again, I will be better able to answer this with an illustration. For now, I think it will suffice that there are populations in Africa whose origin on the human family tree goes back at least 100kya. The genetic diversity in Africa was not as well understood in 2004 as it is now, and we have only scratched the surface. I wonder how that would change their mathematical analysis. As for Veshynsky, I do not think he has Adam and Eve in mind in the same way. So, taking out any theological claims, his theory could have explanatory value.

 

[Neithan]

I agree with you about the unlikelihood of 10,000 years ago; I am just separating the different hypothetical possibilities, and as you know, scientific theories can always change. We should probably go much farther back than Christ, or even Abraham, for the doctrine of original sin and suitable IAs. We do not need to go as far back as Y-chromosome patrilinear or mtDNA matrilinear MRCA descent, however.

Dr Vyshedskiy is not concerned with Adam and Eve; however, “Romulus and Remus” are, as monozygotic twins, the least likely possibility according to his hypothesis. We could suppose a male and female in the same tribe of hominins who are the first “true” human beings, who then mate. This is only one possible hypothetical way to reconcile the genetic and anthropological record with Humani Generis and I venture to say you will never find certainty on this point, only a lot of speculation.

 

[Dovekin]

how on earth could characteristics be associated with rationality and not actually be rationality itself?

There are lots of behaviors among animals that are associated with rationality. Crows use tools to get food. Bees have complex social systems, including ritual like language. Etc. It is possible for hominids to have these behaviors as well, while remaining animals.

At some point in history, a rational soul was given to a true human, presumably the child of hominids. The hominid behaviors that look like rational behavior are not lost, but the child who has a rational soul will give them a new significance and importance by using them rationally.

A rational soul is not a fully defined term. A continuous development of rational characteristics may occur from the immediate gift of a rational soul in the middle, or it may be the evolution into a rational soul. I do not think we can tell which it is without further defining the rationality and soul. But I think Aquinas would understand it as the immediate gift of a rational soul to a first individual.

 

[Dovekin]

the determining factor as to whether something has a soul or not becomes…whether it has a soul or not.

Yes, this is the situation. Some think they can define rationality, intellect, or soul well enough to be able to identify the soul’s presence by examining behaviors or body parts. I have my doubts. The soul is a spiritual reality with a spiritual definition that does not correspond directly to physical behaviors.

 

[Gorgias]

I don’t necessarily have a requirement that they be the MRCA of the whole extant genome

M R CA. Kinda loses its meaning when you’re attempting to posit the very first ancestor, no? The “LRCA”, as it were?

However, if the claim is that every human alive received their fallen nature from Adam and Eve’s choice, then they have to have existed far enough back in time to make it biologically possible that every human alive by, say, the time of Christ had a rational soul by this process. Otherwise the great commission is a fool’s errand because not everyone had a soul to save.

Why is this so difficult to believe?