Phil, I appreciate your taking so much time to assemble those arguments. A thorough rebuttal would take a lot more time than I have available, so I'll have to make do with a few general comments.

If I understand you correctly, you are attempting to demonstrate the mind-independent existence of concepts, particularly of those concepts we refer to as universals. My position is that, while such their existence as such may be assumed, reason does not compel that assumption, and so I am epistemologically blameless if I don't assume it. I have also offered an account of how we could have acquired the ability to use concepts notwithstanding their nonexistence outside of our minds.

"Triangularity", "redness", "treeness" are not reducible to any particular triangle, red thing, or particular tree.

My account requires no such reduction.

Geometry deals with perfect lines, perfect angles, perfect circles, etc. and we discover objective facts about them. We didn't invent these facts, we discovered them, and since we can't change them--they do not depend on our mind.

I think that's a non sequitur. I don't see what changelessness has to do with mind-independence. Besides, we did have to change a few of the "facts" we thought we knew about geometry, when we discovered the coherence of non-Euclidean geometries.

Mathematical truths in general are necessary and unalterable, but the material world is contingent and changing.

Again, you aren't showing me how "necessary and unalterable" entails your conclusion.

Also, while I note your "in general," which implies that there could be exceptions, I don't think those exceptions are irrelevant to your argument. Over the course of history, mathematicians have had to revise some pretty fundamental ideas about what they can truthfully say.

These mathematical truths were true before the human mind existed and would still be true is the human mind ceased to exist.

I suppose so. Two plus two was four before we came along, and it will be true after we're gone. I just don't see how that makes two, four, or any other number any more mind-independently real than Capt. Kirk or his starship.

Propositions cannot be idenified with anything that is purely material or purely mental (in the mind).

They don't need to be so identified in order to be useful. They just need to have some correspondence with things that are material or mental.

Even if there never was a material world or a human mind, the proposition "there is neither a material world nor a human mind" would still be true. Therefore propositions are neither material in nature, nor do they rely on the human mind for existence.

You seem to be conflating truth with existence. We can make true statements about things that aren't real.

A person can utter the same word and it applies to many different physical existing things--such as saying "red". This is enough to show that the meaning attached to the word transcends our mind and the physical world.

Meaning is not the same as reference. A word can refer to something that is neither in our minds nor in the physical world, but the meaning exists only in our minds.

When we entertain the same concept, say "treeness" or "redness", we are each entertaining the same one concept. You aren't entertaining your private concept of "red" and "tree" and I my own private ones, with nothing in common in between them.

We have to assume that, if we're using those words and understanding one another. As soon as it becomes apparent that we're not understanding one another, we have to question that assumption, because it might be unwarranted.

This leads to the next point. We would never have access to each others private concepts of "red" and "snow", and therefore interpersonal communication would become impossible. But we can communicate, therefore concepts are not purely mental.

You cannot access my private concepts the way I can access them. I am the only one who can know, certainly and precisely, what the word "snow" means to me. The same goes for you and what the word means to you. But we can confirm, just by talking to each other, that we mean the same thing when we talk about snow. This, as far as I can tell, proves nothing beyond the fact that you and I speak the same language.

Hey Doug,

So I was able to put together a short list that goes over the reasons we have for believing that universals/concepts are not a physical thing and are also not purely a mental entity that exists only in the mind This also shows why it is rational to believe, beyond a reasonable doubt, that immaterial abstract concepts do exist (and humans can in turn understand them, which tells us something about the nature of the human intellect!):

1) One over many argument: "Triangularity", "redness", "treeness" are not reducible to any particular triangle, red thing, or particular tree. Or even to any group of those things. Any of those particular instances of them could go completely out of existence, but they could always come back into existence (e.g., all "red" objects disappearing, but "redness" could always come back into existence).

Also, the "redness" of an object exists even when no human being is thinking about it. Hence concepts/universals are not material things nor collections of things, and neither do they only exist in the human mind.

2) Geometry: Geometry deals with perfect lines, perfect angles, perfect circles, etc. and we discover objective facts about them. We didn't invent these facts, we discovered them, and since we can't change them--they do not depend on our mind. Since they are necessary and unalterable, and no material object has the perfection that geometrical objects have, they do not depend on the material world either. Hence geometrical objects are immaterial concepts that exist outside our mind, yet are not physical objects.

3) Mathematics in general:Mathematical truths in general are necessary and unalterable, but the material world is contingent and changing. These mathematical truths were true before the human mind existed and would still be true is the human mind ceased to exist. The series of numbers is infinite, but there can only be a finite number of physical things, or a finite number of human ideas. Therefore, mathematical truths are not material things, but they do not also depend on the human mind. They are immaterial abstract entities.

4) Nature of propositions: Propositions cannot be idenified with anything that is purely material or purely mental (in the mind). Some propositions like mathematical ones are necessarily true and remain true if the material world ceased to exist or if the human mind went out of existence. Others like "Einstien was born in Germany" also would remain true if the material world ceased to exist or if the human mind went out of existence. Even if there never was a material world or a human mind, the proposition "there is neither a material world nor a human mind" would still be true. Therefore propositions are neither material in nature, nor do they rely on the human mind for existence.

5) Science: Science points out facts that are mind-independent, and relies on mathematical formulations and universals. To affirm the findings of science is to affirm the non-material nature of universals/concepts, and therefore the non-material nature of the human mind.

6) Words are universals too: A person can utter the same word and it applies to many different physical existing things--such as saying "red". This is enough to show that the meaning attached to the word transcends our mind and the physical world.

7) The objectivity of concepts and knowledge, and possibility of communication: When we entertain the same concept, say "treeness" or "redness", we are each entertaining the same one concept. You aren't entertaining your private concept of "red" and "tree" and I my own private ones, with nothing in common in between them. This leads to the next point. We would never have access to eachothers private concepts of "red" and "snow", and therefore interpersonal communication would become impossible. But we can communicate, therefore concepts are not purely mental.

[Note: these are a summary from some of the books I have recommended around here]

If memory serves, he provides a clear example of something human beings do, which cannot possibly be done by any algorithmic computing device.

It was clear to him, perfectly clear, that the example proved his point that the brain was doing something that no computer could ever do. That argument depends on defining computers in terms of strict reliance on algorithms.

It is apparent that our brains, whatever they do, aren't doing it the same way that electronic computers do what they do. It does not follow that our brains are not doing what electronic computers do.

Penrose presented a rebuttal in that book. It was not a refutation.

If memory serves, he provides a clear example of something human beings do, which cannot possibly be done by any algorithmic computing device. It was structured around the question of whether an algorithm will complete or not.

If you put certain information into a system and get certain other information out, then the system is a computer.

Is the digestive system a computer? How about rainfall on a mountain? I read some time ago that materialist reductionist accounts eventually lead to pantheism or animism.

I will call it a day as I think we are, as you said, at a point where there is just a fundamental difference. I do appreciate the great conversation!

You've presented some interesting challenges. Thank you for the workout.

This is great--Nagel ends his overview chapter by stating:

"That order would have to include physical law, but if life is not just a physical phenomenon, the origin and evolution of life and mind will not be explainable by physics and chemistry alone. An expanded, but still unified, form of explanation will be needed, and I suspect it will have to include teleological elements. All that can be done at this stage in the history of science is to argue for recognition of the problem, not to offer solutions."

It is as if Nagel does not realize that Aristotle provided us with a very powerful explanation almost 2000 years ago (which then Aquinas expanded it to unify it even more, and Edward Feser is expanding our understanding of its harmony, and explanatory power, with the natural sciences even more today).

At least Nagel recognizes the need for teleology, hence Aristotle's "final causality"!

I will call it a day as I think we are, as you said, at a point where there is just a fundamental difference. I do appreciate the great conversation!

In the end it seems that the main difference is that you don't mind holding an assumption that cannot be supported by its own theory (that human minds are all the same/similar, which is indefensible because one has to know the nature/universal of the mind to show it to be true), while I would hold that all endeavors for truth, whether they be scientific or philosophical in nature, should not lead directly to internal incoherency of this nature.

---

Anyway, wanted to pass along that I started reading this interesting book by Thomas Nagel--"Mind and Cosmos". He is talking about the prominent issues with reductionistic materialism and its inability to account for mind. (Ultimately, he holds that this metaphysical worldview will come to be held as prominently false.) He comes at it simply from a philosophical and scientific POV.

I am only about a third of the way through and his focus of the book is not to propose an alternative, but simply to show that materialism is false beyond a reasonable doubt. He throws out some ideas of what could replace it, but interestingly enough it doesn't appear that a hylomorphism along the lines of the Aristotelian-Thomistic metaphysical tradition is on his radar!

He says that he is staying away from any type of religious motivation in this book, so I always wonder if non-religion affects a person's ability to genuinely address hylomorphism. (Or it could be the fact that he is not familiar with it. After 2000 years of staying power, it makes me wonder how someone in the philosophical community could not be familiar with it!) Oh well, at least he makes his point well about the incoherency of materialism!

Have a blessed new year!

but I still think the big point of difference is that you would not hold that universals/concepts/natures exist whatsoever outside the human mind, right?

I have no idea. Are you talking about three different things, or are you offering me a choice of labels for the same thing? I don't believe universals = concepts = natures.

I hold that they exist, and actually originate, in external entities and the human mind is capable of abstracting these universals/concepts/natures from external reality.

So I gather. That is the topic we've been debating, isn't it?

but on your proposal that is all we receive; only random bits of sense data which the mind then places into order with what we call "universals/natures".

My proposal says nothing about our sensory data being random.

Does the sense data that comes to us have any order already, or is it just random and the mind places order upon it?

We should not presuppose that it is all either one or the other. Some of it seems ordered and some of it seems random. It's up to us to figure out, using the cognitive tools we have, how much of it really is ordered and what kind of order it really has. We should be prepared to discover that there is order in some of the apparent randomness and that some of the apparent order is illusory.

It seems that you might hold that the human person receives sense data that isn't just random, but actually has order to it? This means you would not hold as I said in my previous comment that "we only receive random bits of sense data which the mind then places into order with what we call "universals/natures". Is this correct?

I'm uncertain whether it is correct because your meaning is not entirely clear to me.

As I just got through saying, we should not presuppose one way or the other. But having said so, I also note that we could not long survive without assuming that there is some order in at least some of the sensory data we get.

Now if you do hold that the data comes already to us ordered, then you do actually hold that universals do exist outside the mind.

That depends on what you mean by "hold." I have already stated, more than once, what I believe about the existence of universals, and you have said nothing yet that makes me think I have been mistaken.

On the theory you are proposing (conceptualism): . . . . you first have to assume that the human mind bestows a universal concept/nature upon the object of "human mind" in a correct and similar/same way as most everyone else.

That is not my theory or what it must assume. That is your restatement of something it must assume.

The only thing I'm assuming about human minds is that, in general, those of other people are just like mine in certain basic respects. If you think this is an indefensible assumption, then you and I are at a dialectical impasse. But please note that I can make this assumption without having the foggiest notion of how anybody's mind actually does work. It is consistent with any general theory of human cognition. It is just as consistent with Roger Penrose's thinking as it is with mine. Indeed, I don't think Penrose could defend his own theory without this assumption.

Then, given this assumption, if I believe more particularly that my own mind works as my theory says it works, then I reasonably believe that other people's minds work that same way. This is not a circular argument.

when it comes to proposing explanations/theories for explaining reality, no matter whether it be a scientific or philosophical theory, the most rational and best explanation to hold is the one that is the most internally coherent (i.e., does not have internal issues, internal contradictions), is the most consistent (i.e., internally logically, and with other reasonably accepted theories), and is the most comprehensive (i.e., explains the most data).

So far as I can judge, mine meets those criteria, and I think it also has the advantage with respect to parsimony. Yours asserts the existence of entities that mine does not.