Question about Thomistic Philosophy and Evolution.
#11
(05-05-2020, 04:31 PM)MagisterMusicae Wrote:
(05-05-2020, 10:36 AM)FultonFan Wrote: Therefore, in the light of Thomistic philosophy, the change would be in the accidents rather than in the essence.

In what is often termed "microevolution", yes. That would be accidental change. A species develops dark hair vs. light hair.

However, "macroevolution" would assert not mere accidental changes, but substantial changes. A species is transformed into a new species. At some point these are different kinds of things, meaning a change in the essence/nature/substance, not mere accidental change.

The problem with the latter from a scholastic perspective is that there must be a sufficient cause for this substantial change. If the new species is more complex, then that added complexity cannot come from the lower complexity without an proportional cause, which "random chance" is not.

Which is why one would need to assert some external proportional cause for this increase complexity, such as God directing these changes.

A flea is not directly disposed to become a cat through mutation, nor is even a horse disposed to become a zebra, and so if there is a lack of disposition, then there has to be some external force which disposes if that were to happen.

In short, Darwinian unguided evolution presents a philosophical impossibility without invoking additional causes.


Re: Macroevolution problem.  If you took a ball composed of 100 quadrillion grains of sand, such that each grain and spacing from the other grains was uniform, and then pulled grains together into clusters to form spirals, tendrils, filaments, etc., the sum of sand grains would certainly be aesthetically more complex, but wouldn't they, as a whole and individually, be substantially unchanged in complexity from their uniform state?
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#12
(05-06-2020, 11:26 AM)Melkite Wrote: See, that's my problem with applying Thomistic substance/accident language to non-human creatures. How do we know that all those animals you mentioned are in "essence" cats? That label was arbitrarily applied the a certain group of animals based on biological aspects. In other words, we determine the substance of an animal by its accidents. That seems illogical. If we can only use accidents to determine substance, and accidents are not essential and are thus able to change from animal to animal, it would follow that we have no reliable method of even determining what the "substance" of the animal is.

This leaves us with two options:
1. Animals are composed purely of accidental nature. In other words, the physical aspects of an animal determine its identity.
2. All animals have the same substance. Though maybe differing in degree, if you believe that animals have some sort of a spiritual reality, and that more complex ones have more complex spiritual realities.


Imo, the bolded part is the logical checkmate to the anti-evolutionist position.  The idea that evolution can happen on a microscale within clades is the pinnacle of defending literal creationism in the face of a superabundance of evidence in favor of some kind of evolution.  Once this pinnacle is taken down, there is nowhere else for the literal creationist to go, other than to return to an insistence that the biblical account is literal history and fossils are lies placed in the dirt to test our faith.
The metaphysics of what makes a cat a cat, etc., are not relevant to the discussion as to how the cat emerged. Nor is it relevant to the question as to whether a lion and a tiger are relatable as cats. The argument in bold is thus a non sequitor. It's not a logical checkmate since the question doesn't even address anything substantial to the metaphysics of species. These are entirely different  issues and philosophical questions.
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#13
newenglandsun Wrote:The metaphysics of what makes a cat a cat, etc., are not relevant to the discussion as to how the cat emerged. Nor is it relevant to the question as to whether a lion and a tiger are relatable as cats. The argument in bold is thus a non sequitor. It's not a logical checkmate since the question doesn't even address anything substantial to the metaphysics of species. These are entirely different issues and philosophical questions.

Well, I'm an armchair philosopher at best, so perhaps that is correct in a way I don't understand. But what I bolded in Luke's comments is correct. We presume a cat is a kind because lions and tigers and domestic cats have features we recognize as similar. But if we admit these things can change somewhat within a kind, how can we propose to set the limits to that kind? The creationist defines kinds based on arbitrary aesthetic resemblance. The evolutionary biologist at least uses more substantial evidence in his definition of clades. Bearcats look like the rabid demon-spawn of a cat and a raccoon, and hyenas don't look like cats at all. I imagine creationists would not recognize hyenas as being in the kind of cats, yet if you look at evidence beyond the superficial, we can see that they are. I think Luke's point stands. We define kinds arbitrarily based on a presumption of the thing's essence. Yet we cannot know for sure what its actual essence is, if we admit to the changing of features such that the one becomes unlike the other. This is why I see it as a checkmate of the literal creationist position.
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#14
Melkite,
What exactly of what I said indicates I don’t understand the argument?
The giraffe analogy is essentially exactly what I understood as the evolution argument.
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#15
(05-06-2020, 02:31 PM)FultonFan Wrote: Melkite,
What exactly of what I said indicates I don’t understand the argument?
The giraffe analogy is essentially exactly what I understood as the evolution argument.


I guess I misread you, but in your original post, it sounded like you were saying the mutation doesn't lead to a true change of species because it may not reappear in the mutated individual's offspring.  Sometimes that's true, but sometimes it's not.  Some traits automatically present if one of the parents possesses the gene and pass it onto their offspring.  It sounded as if you were dismissing the whole thing because sometimes traits don't pass on.  But if that's not how you meant it, ok.
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#16
(05-06-2020, 10:18 AM)lukeg03 Wrote: See, that's my problem with applying Thomistic substance/accident language to non-human creatures. How do we know that all those animals you mentioned are in "essence" cats? That label was arbitrarily applied the a certain group of animals based on biological aspects. In other words, we determine the substance of an animal by its accidents. That seems illogical.

You've got it backwards.

A definition of a species would be genus + specific difference. Human beings are rational animals. We are animals, and the specific difference is "rational". This is something of our essence which distiguishes us from all others.

The problem with non-human animals, plants, and even non-living matter is that while we can grasp something of the essence in using our senses and reason, we cannot make a proper definition. We know that a lion is an animal, and so is a cat, but we cannot see exactly what makes this animals specifically different from another. So we resort in such cases to an improper definition, which is a description of proper accidents which effect the same thing : to distinguish this species from another.

"Cats" would be the genus, or the "kind". But what makes a common house cat specifically different from wild species that look very much like it is not clear, and perhaps, there is no difference in essence, only in accidents.

The problem is that we don't have direct knowledge of the specific difference of most things, so we resort to descriptive definitions. A listing of unique or "proper" accidents is a substitute for the specific difference.

That is not "determining the substance" by the accidents. Substance is not essence. It is trying to use accidents that we notice are unique to certain substances which can then suggest that these substances share a common nature which is distinct from other natures.

Perhaps you're just confusing your terms, and that's the reason for your statement. It seems to me, though, that you have done a bit of Thomistic/Aristotelian study, enough to learn the terms and have a basic understanding a few things, but you did not engage much in Metaphysics or Informal Logic taught in this a Thomistic manner (or perhaps are forgetting those parts) if you can't see that making an improper definition from proper accidents since the actual specific difference is unknown, is not "determining a substance from its accidents".

(05-06-2020, 10:18 AM)lukeg03 Wrote: If we can only use accidents to determine substance, and accidents are not essential and are thus able to change from animal to animal, it would follow that we have no reliable method of even determining what the "substance" of the animal is.

Again, you seem to confuse "essence" and "substance", which are very different things.

Accidents are not essential. Neither is substance "essential". The essence is the nature of a substance. A substance possesses a nature and is an individuated thing which participates in that nature. I am a human being, which means I am a substance which is an individuated participation in human nature. We usually say, I possess a human nature. It is that nature which gives the essence of what I am.

The problem in Thomism about evolution is the question of sufficient reason/disposition.

Certainly we have substantial changes, and the new form which is take up in a substantial change is essentially different from the previous form. This happens all the time, but only when the former substance is disposed to the new substance. Wood can become ash by burning (a substantial change) which also causes accidental changes. The essence of wood and ash are different, but since we do not know what they are we describe them rather than give their specific difference.

It is clear that an animal with dark hair is disposed to have light hair, and that our genetics certainly can be changed through natural processes to pass on accidental traits. A substantial change, however, is impossible without a sufficient cause and the disposition of the subject.

Chance or "Survivial of the fittest" is not a sufficient cause, and kind produces kind, so there is no moment at which one animal could give birth to a new kind of animal with a different essence. That is a kind of "creation" if the form/essence is not already potentially in the animal, which does not seem to work.

Rather if a Thomist is going to posit some "evolution" he has to invoke an external and intelligent force. A Thomist could be a Theistic Evolutionist, or Progressive Creationist, but not a Darwinian evolutionist.

(05-06-2020, 10:18 AM)lukeg03 Wrote: This leaves us with two options:
1. Animals are composed purely of accidental nature. In other words, the physical aspects of an animal determine its identity.
2. All animals have the same substance. Though maybe differing in degree, if you believe that animals have some sort of a spiritual reality, and that more complex ones have more complex spiritual realities.

And because of your lack of exposure to Informal Logic and Scholastic Metaphysics, or perhaps because you've neglected that, you then end in a fully insane dilemma, which simply does not follow at all.

Neither of these two options is possible or follows if you understand your terms correctly. Confuse substance with essence (a very fundamental error) and in fail to understand the Scholastic method of definition and substitution of proper accidents as an informal definition (a still fundamental, but more excusable error), and then I'd agree with your two options.

But correct those errors and these two options simply do not follow.
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#17
(05-06-2020, 12:03 PM)Melkite Wrote: Re: Macroevolution problem.  If you took a ball composed of 100 quadrillion grains of sand, such that each grain and spacing from the other grains was uniform, and then pulled grains together into clusters to form spirals, tendrils, filaments, etc., the sum of sand grains would certainly be aesthetically more complex, but wouldn't they, as a whole and individually, be substantially unchanged in complexity from their uniform state?

You're describing an accidental change only, so yes, they would be substantially unchanged.

That said, 100 quadrillion grains of sand is 100 quadrillion substances, not one substance, unless we consider them an accidental unity/whole. So what you are describing is rearranging parts in an accidental unity, or 100 quadrillion individual substances in a particular spatial arrangement.

It's still 100 quadrillion grains, unless something happens which unites them to produce something other than 100 quadrillion grains of sand.

My sand castle is still just sand. I happen to have given it an accidental form, but not substantially changed it. Melt it and produce glass and I have.
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#18
(05-06-2020, 11:10 AM)Melkite Wrote: Proto-giraffe with a normal neck procreates, and the embryo mutates a gene.  This gene makes the baby giraffe have an abnormally long neck.  Baby giraffe grows up, eats low leaves with his peers, and also high leaves his peers can't reach. Baby giraffe mates a few times, passes the gene onto half of his offspring.

Next generation: several long-necked giraffes compete for food with several short-necked giraffes.  Because of the broader height range of food availability, the long-necked giraffes are better nourished overall than the short-necked giraffes.

Next generation: more long-necked giraffes have been born now, and a few of them bully the short-necked giraffes by eating all the leaves closer to the ground.  A few short-necked giraffes are malnourished, and don't survive long enough to procreate.

Next generation: a sufficient number of long-necked giraffes exist to put the short-necked giraffes in their communities into serious threat of starvation. 

Over the course of the next many hundreds or even thousands of generations: Many short-necked giraffes are unable to procreate before their early deaths.  Of the females that survive, their mating options are increasingly likely to be a long-necked giraffe.  Each new generation has even more long-necked giraffes being born.  Because the long-necked giraffes are getting adequate nutrition to sustain them until mating age, and the short-necked giraffes are not, the long-neck population is growing exponentially, and the short-neck population is frequently halving.  Eventually, there are only a handful of short-necks left, and they cease to exist when either the last one dies before procreating, or procreates but its progeny do not display the short neck gene.

When does one of these animals cease to be a giraffe with mutated features and start to be some other kind of animal which is non-giraffe?

That's the issue.

There is no philosophical issue with accidental changes. The issue is with substantial changes.

So at what point does mama giraffe give birth to something which is non-giraffe?

The only explanation I have heard is that eventually we call that new animal a different species, which means we fall into nominialism (there are no essences/universals, it's just individual substances that we give names to and group together) or eventually a kind of pantheism or monism.
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#19
MagisterMusicae Wrote:When does one of these animals cease to be a giraffe with mutated features and start to be some other kind of animal which is non-giraffe?

That's the issue.

There is no philosophical issue with accidental changes. The issue is with substantial changes.

So at what point does mama giraffe give birth to something which is non-giraffe?

The only explanation I have heard is that eventually we call that new animal a different species, which means we fall into nominialism (there are no essences/universals, it's just individual substances that we give names to and group together) or eventually a kind of pantheism or monism.


I do think that nominalism here is partially correct. In your response to luke, you mentioned that we can't be sure of the essence; we can only observe differences that may refer to its essence. What if our cataloguing is all wrong? Or not particularly accurate. Perhaps the species of a lion and the species of a wolf are substances in the essence of a carnivore (if I'm using substance and essence correctly - still not sure if I am, although I think I have it based on your explanation above). In the same sense that all men are in Adam, could it be that all animals are in one essence, such that macroevolution no longer poses a philosophical problem? Is it possible the essence we are speaking of is life itself, and is not to be divided any further than that? This is where I was going with my sand analogy.
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#20
(05-06-2020, 05:03 PM)Melkite Wrote: I do think that nominalism here is partially correct.

And that's really what one sees in the modern naturalistic/atheistic science, and it is that thread that leads us to the whole "identifying as" whatever in today's world. If a man is just what we call someone who feel a particular way ...

So, I don't see nominalism as any solution, but really as part of the denial of reality ... that's a separate discussion, perhaps.

(05-06-2020, 05:03 PM)Melkite Wrote: In your response to luke, you mentioned that we can't be sure of the essence; we can only observe differences that may refer to its essence.

Sort of.

The essence/quiddity/nature are more or less the same thing which describes deeply what a thing is. This essence relates (in the created world) the substantial form that a thing possesses.

Adam knew the essences of everything, which is why he could name them—a true name being in some way related to what these things are. If we had to define a "lion" we would normally identify the genus (kind) and the specific difference—what specifies this species. A lion might be a leonine animal, just as a man would be a rational animal.

The problem is that we don't know what constitutes "leonineness". We can only describe it using accidents that do not seem to belong to other things or whose combinations do not seem to be found elsewhere.

A zebra is a zebrine animal, but the best we can do is say something unique to a zebra is that it's a black-and-white stripey equine quadruped. It distinguishes it, but fails to completely express the essence, it only gives a hint at things which belong to this essence.

Our definitions are meant to be definitive, but often can only be descriptive.

(05-06-2020, 05:03 PM)Melkite Wrote: What if our cataloguing is all wrong?  Or not particularly accurate.

Absolutely possible, given that accidents are not entirely definitive, but more descriptive. We could identify two things which are essentially different as one, if those differences are so minute that we're unable to distinguish.

I'd say that's very much like what has happened in particle physics. The name "atom" comes from α + τόμος (a + tomos) meaning "inseparable" because the atom was thought to be the basic building block of matter. Refine things and now we have 38 elementary particles, arguably more.

So it's entirely possible that we've done some of the descriptive work in biology wrongly.

(05-06-2020, 05:03 PM)Melkite Wrote: Perhaps the species of a lion and the species of a wolf are substances in the essence of a carnivore (if I'm using substance and essence correctly - still not sure if I am, although I think I have it based on your explanation above).

No, you're not using substance and essence correctly, but I get what you're saying.

The division is genus (kind) and species. There can be many levels of this provided a specific difference exists between genus and the species in that genus. A genus can have a nature or essence in a broad way of speaking, so we could speak of an animal nature, or that sensory powers belong to the essence of animals.

Substances are individuals with a particular essence. So a particular cat is a substance. Essences are what deeply a thing is, so a cat has the essence of a feline.

Cats (in the abstract) are not substances in some essence. They are species in a genus, who have a feline essence/nature.

Okay. That aside, because genus (kind) and species are just relational divisions, there's no issue suggesting that the "kinds" that God created are in fact larger groups, such as carnivores, rather than the biological clade, family or genus that we use, however this really can only work to a point, because while a dog and wolf are close enough in behavior and accidents that perhaps they have the same nature/essence, it's pretty clear that a panther and a dog are different in nature/essence.

This derives from the axiom that "a thing acts according to its nature" so if we see significantly divergent behavior in two animals, we would propose that they do not share the same nature, and so while we might group them together as similar in kind, they are really distinct species.

Modern biology, unfortunately doesn't look at behavior and action, but instead at genetics and the ability to mate to determine biological species. Granted, these are accidents, and descriptive, but this creates problems. For instance the bottlenose dolphins in the Northern Hemisphere and Southern are quite different in appearance, and so some think they are a different species, since they do not mate (even though they could possibly) and have some distinct genetic markers, but others say they are just two separated groups in one larger species because they act the same and genetically could mate, even if they don't.

It is important to remember that the genus-species in Thomistic philosophy is only analogical to the biological divisions.

In short, we could expand the idea that the biological "genus" and "species" are badly defined (I'd agree, in fact), and perhaps the "kind" mentioned in Genesis is really at the biological level of "family" or even higher. The question will be at what level are we so different in behavior that these things are clearly different kinds.

Thomistic Philosophy would not have any issue with purely natural processes (though always intended by and so willed by God anyway) generating many biological "species", which are really just variations on the same "kind" and sharing the same essence/nature.

The problem comes in the jump from one nature to a new nature, like the giraffe. It's repugnant that mama giraffe would not give birth to a giraffe, even if 1,000 generations later they are short stripey creatures that look like zebras. They would still be giraffes, unless some exterior force has caused some change.

(05-06-2020, 05:03 PM)Melkite Wrote: In the same sense that all men are in Adam, could it be that all animals are in one essence, such that macroevolution no longer poses a philosophical problem?  Is it possible the essence we are speaking of is life itself, and is not to be divided any further than that?  This is where I was going with my sand analogy.

Life is a genus, and different kinds of life certainly are "species" or sub-genera, but again, because nature specifies action, clearly my tomato plants are of a vastly different nature/essence than me, or my pet ducks (if I had any).

So life is too general to be the "essence" we all share. It is a part of that essence.

Look. I don't think there is a philosophical problem with "evolution" if one is a "theistic evolutionist" or "progressive creationist" materially these produce the same biological result. I don't hold those positions, but I don't see the philosophical problem with these, because one asserts a sufficient cause for the changes and new natures/essences which are being created.

The philosophical problem in Darwinian or similar evolutionary systems is in the "random" changes, and the jumping between natures without sufficient cause. Take the Darwinian randomness out and substitute in God, or the Providential plan as the sufficient cause, and it does solve the issues in philosophy, but then does bring up some theological difficulties. These are not unsolvable, but one reason I don't choose a system is that none (even 168-hour Creation) provides a very comfortable setup.

The 168-hour creation seems to pose problems with God's Providence in seeing fossils that are veritably much older that 10,000 years ago. The YEC solution is to throw out modern science is unreliable or unable to access the antediluvian universe (and oddly then many appeal to "Creation science" based on that "unrelaible" science). Sticking to this calls into question God's veracity, since it seems He is suggesting an old earth by science, but in fact it's all a deception. Seems to go against that Act of Faith in He "who can neither deceive nor be deceived".

The theistic evolution position and progressive creationist positions also suffer from questions in theology about requiring either God's constant intervention in the world to produce new creatures, which is not very easy to fit into the notion of Creation as the production of something from nothing and Providence all at once disposing in a single act all of Creation in His plan. The alternative is that Providence put into the primitive kinds all of the information/dispositions to potentially become the variety we see, but then you would think we would see that in the genetics or information storage, but in fact DNA works the opposite way, in that the more primitive life forms are less informationally complex.

In short, I really think all of these viewpoints suffer from deficiencies, but each has something about it which it does contribute, and so is worth exploring, which, since you've been around here long enough, you know reflects my position. Many would like to make me out to be an "evolutionist" but I really do not have any position here. I'm just interested in the scientific, theological and philosophical truth. Those are interesting enough to keep me busy enough rather than shilling for any position.
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