My Ontology – Part 2: Mind-dependence

Open MindIn Part 1 I laid the foundations for my ontological framework and came to the conclusion that my position is currently best categorized as that of conceptualism. In this post I would like to dig into this deeper and examine some of the key issues surrounding the topic of mind-dependence and some of the arguments against the conceptualist view. What does it mean to say that a mind-dependent thing (hereafter referred to as a concept) exists? Some may initially balk at the prospect that concepts actually do exist in some sense, but I think our experience infers our acceptance of this proposition on a regular basis. I suggested in Part 1 that we often include concepts when we speak of things which exist. In addition, we routinely say that we “have an idea” and we can recognize the feeling of “getting it” when an explanation “sinks in”. We have a word “on the tip of our tongue” when we are aware of the concept but unable to express it. A placebo can change our well-being. It seems to me that these are all manifestations of concepts.

In the entry on Platonism, the Stanford encyclopedia of philosophy states that “[conceptualism] has serious problems and not very many people endorse it.” Chris Swoyer suggests that conceptualism warrants renewed consideration and starts by noting that “Somewhere in the twentieth century… conceptualism fell off the map….it’s surprising it continues to receive even the perfunctory nod it often gets…”. As an alternative many either come to accept that these things I call concepts are actually mind-independent (realists) or that they don’t exist at all (nominalists). I hope that in this post I am able to make the case that conceptualism has been overlooked. Of course, it is also possible that somebody will come along and straighten me out and make me realize that I’m actually a nominalist or a realist; but we won’t know unless we try.

A naturalist account of concepts

As it currently stands, I find that the naturalist account of reality is more probably true than the Christian (or theistic) perspective I once held. This means that I should be able to reconcile naturalism with the ontology that I have proposed. The naturalist position unashamedly equates the mind with the brain, and so the existence of concepts must be defined within that context.

neuronsTo start this exploration, I want to re-iterate a perspective that I have offered before. In Part 1 of my epistemology, I proposed that logical reasoning can be explained as a process of mapping relations between experiences (and the labels assigned to those related portions of our experiences) and in the end I came to the conclusion that I am an empiricist. Similarly, in Part 1 of this series, I argued that experiences define our knowledge of objects and thus inform our ontology. Taken as a whole, this perspective appears to be highly compatible with our modern understanding of the brain. Allow me to try and briefly outline this congruence.

First, we are well aware that the brain is highly associative. We regularly employ mnemonic devices to improve our recall, and basic introspection reveals how our train of thought tends to follow along paths which relate concepts. Second, we know that the brain is a somewhat flexible configuration of what is very roughly estimated to be 100,000,000,000 neurons and 1,000,000,000,000,000 synaptic connections, where by “flexible” I mean that the connections can change. The neurons and synapses combine to form neural networks that, as far as we can tell, serve to encode sensation and train our response. Sense data, both external and internal interfaces with the brain and causes the relevant neural networks to update accordingly. Obviously all of this is a rather gross simplification and so, when coupled with the fact that my knowledge of neuroscience is both limited and informal, you would be wise to investigate these things further on your own. Regardless, all of this leads me to a rather simple definition of a mental concept: with each experience our brains are modified with a “shadow” of the sense data from that experience. These shadows are linked with each other (perhaps even shared in some way) when the sense data is phenomenally or temporally similar. Symbols associated with these experiences become linked into the networks, tying words into the mesh. The result is a massive network of neural relations that can be broken into symbolically identifiable segments, where each segment represents a discreet aspect of one or more experiences. This defines a concept. They can be linked to define new, more complex concepts, or dissected to define simpler concepts. The following TED talk (20 min) offers a glimpse into this amazing network.

So, to put it simply, concepts are patterns in the brain. These patterns are byproducts of our experiences and genetics, and persist with varying fidelity. As a result, they are unique to each individual. The sensory encoding process for humankind, however, is generally the same. The resulting patterns then share enough commonality, and relations to symbols, that we are able to agree on the external reality from which they were formed. We communicate this to each other primarily through the use of the word symbols linked to the concepts.

Now lets take this idea to its natural conclusion. If mind-dependent things are really just patterns in the brain, then what is this thing that we are calling a pattern? As I see it, there are two options under this framework: either patterns are themselves something independent of the mind and are a foundational part of all concepts, or patterns are themselves patterns. The first seems to be a theoretical leap based on nothing but the fact that we’ve hit the end of our rope. Alternatively, the second option puts us into an interminable self-referential loop (aka, recursion). While there is something disquieting about this, I am at a loss to explain why it is in any sense invalid. In fact, this may be the only kind of infinite that exists. As a software engineer, I myself have on rare occasion created these interminable self-referential loops. There are other reasons to prefer the self-referential option. For one, we intuitively identify a pattern as an abstract object. It only makes sense, then, that it would remain as such. Recursion also makes sense when you consider the neurophysiology outlined above. If concepts exist within a massive web of interconnectivity, then the potential for self-reference should come as no surprise. I have here breached a rather massive topic to which many are devoting entire lives, yet I shall leave it at that. It is only necessary at this time to define the foundational ontology of concepts for the purpose of further scrutiny.

Objective relations

Mt. Everest, Lhotse, Nuptse

The Stanford article on platonism suggests that one of the stronger objections to conceptualism can be summarized as follows: “…relational claims seem to be objective; e.g., the fact that Mount Everest is taller than Mont Blanc is a fact that holds independently of us; but conceptualism about universals entails that if we all died, it would no longer be true that Mount Everest bears the taller than relation to Mont Blanc, because that relation would no longer exist.”

I may have fried a few neurons thinking about this one. I was at first inclined to suggest that this was no different than my thought experiment in Part 1, where I proposed that the only reason the story of Paul Bunyan seems to survive the death of its lone storytellers is because the concept of the story remains in my mind. Similarly, I thought, the “taller than” relation (and similar relations) only appear to be objective because the concept remains in our mind when we consider the example. It then occurred to me, however, that there is a key difference to be taken into account. The “taller than” relation would seem to be clearly discoverable without having ever been transferred from another mind. In some sense, it appears that the relation is not completely mind-dependent.

So I started working from the ground up. I asked myself what it means when we say that something is “taller than”. I concluded that we are expressing a perceived difference in the amount of space the objects occupy in the vertical dimension. This space is a quantifiable, observable object. So the “taller than” relation actually has a referent – the space that is occupied by the taller object and is not occupied by the shorter object. I am venturing to propose that this holds for all objective relations. For example, “brighter than” refers to the photons emitted by the brighter object which are in excess of the photons emitted by the dimmer object. “Faster than” refers to the change in space-time covered by the faster object that isn’t covered by the slower object. The examples could go on and on. If you have a counter-example of an objective relation that has no referent in the physical world (i.e., space / time / matter / energy), please send it my way.

What does this mean? It means that objective relations are very much like concrete particulars and their corresponding universals. The particulars are differences which correspond to quantitatively identifiable aspects of the physical world that we experience. These experiences are then linked together in generalizations that we assign labels. The “taller than” relation is an effective and convenient shorthand for expressing differences in the amount of vertical space occupied by objects, just as calling something a table is an effective and convenient shorthand for referring to all our past experiences of similar objects. So it would seem that the ontology of objective relations should be viewed no differently. If all minds are extinguished then the universal concept of a table no longer exists, but the particular table objects remain. Likewise, the generalized concept of a “taller than” relation does in fact disappear when all minds are extinguished, but the particular instances of physical differences do not.

The problem of universals

If I have thus far explained myself well, it should already be obvious that I see universals as concepts in the mind. Even so, it would be careless for me to summarily dismiss it on that note. Conceptualism, some say, doesn’t address the problem of universals. To quote from the Internet Encyclopedia of Philosophy:

Conceptualism’s appeal to concept application must concern only correct concept application. As such, it is fair to ask, “What makes it the case that the concept red is rightly applied to both a and b, but not of some third individual, c?” To treat this fact as brute and inexplicable is to revert to problematic Predicate Nominalism. So it seems the Conceptualist must say that the concept red applies to a and b, but not c, because a and b share a common feature, a feature c lacks. Otherwise, the application of red is unconstrained by the individuals to which it applies. But simply noting that a and b resemble each other isn’t going to help, because that just is the fact we originally sought to explain, put differently. The Conceptualist might now say that a and b share a property. But if this isn’t to amount to a restatement of the original datum, it must now be interpreted as the claim that some entity is in both a and b. That, of course, turns our supposed Conceptualist strategy back into Realism. Critics say Conceptualism solves no problems on its own. In trying to ground our right to predicate the concept red of a and b, we are driven back to facts about a and b themselves and that leaves Conceptualism as an unstable position. It teeters back and forth between Realism, on the one hand, and Nominalism, on the other.

I suspect that this objection is levied against a form of conceptualism in which concepts are not formed through experience. Allow me to try using the proposed framework to answer the key question of this objection: “What makes it the case that the concept red is rightly applied to both a and b, but not of some third individual, c?” Answer: There is a frequency range in the electromagnetic spectrum for which objects a and b emit or reflect light and object c does not. The sensory input from electromagnetic waves in that range is associated with neural structures that collectively form the concept of redness, and we call this concept “red” because those structures have further associations with the word “red”. The sensory input from object c does not create the same associations and so the concept of “red” is not applied to it. At the risk of sounding pompous, it seems to me that the discussion ends there. Have I missed something?

“Red”, as a universal, can be easily associated with particulars, namely the electromagnetic waves in a certain frequency range. When the universal in question is the type which is a categorization of particulars (e.g., red, table, chair, etc…), the application of conceptualism is clear – the universal is the concept that links our experiences of the particulars together. There are other types of universals, however, which assign properties to objects and that have no obvious referent. We might say that something is hot, flat, smooth or loud. How do these types of universal properties fit into the conceptualist framework? The answer lies in the discussion of relations above. The similarity between relations and these types of property universals becomes clear upon consideration of what these properties are really saying. When we say that something is hot or cold, flat or steep, smooth or sharp, or loud or quiet, we are in fact expression a relation to the norm, or a relation to other spatially or temporally nearby objects. If we’re standing in a walk-in freezer then we might say that an object at 10° C is warm, but we might say that the same object is cold if we are in a stifling equatorial jungle. A knife is sharp because most objects don’t have edges that cut, but a knife can be dull if it doesn’t cut like it used to. These are all relations and, as previously discussed, that means that they all have particular referents in the physical world from which the experiences combine to form concepts.


Mary the color scientist Mary is a brilliant scientist who is, for whatever reason, forced to investigate the world from a black and white room via a black and white television monitor. She specializes in the neurophysiology of vision and acquires, let us suppose, all the physical information there is to obtain about what goes on when we see ripe tomatoes, or the sky, and use terms like ‘red’, ‘blue’, and so on. She discovers, for example, just which wavelength combinations from the sky stimulate the retina, and exactly how this produces via the central nervous system the contraction of the vocal chords and expulsion of air from the lungs that results in the uttering of the sentence ‘The sky is blue’.… What will happen when Mary is released from her black and white room or is given a color television monitor? Will she learn anything or not? It seems just obvious that she will learn something about the world and our visual experience of it. But then is it inescapable that her previous knowledge was incomplete. But she had all the physical information. Ergo there is more to have than that, and Physicalism is false.Frank Jackson, Epiphenomenal Qualia (1982)

The “knowledge of” entails a completely different kind of pattern in the brain than does the “experience of”. Setting aside the likelihood that color concepts do not consist of the exact same pattern in each person, the knowledge that Mary possesses is only present in the form of the patterns of the information she has acquired through her research. According to the story, the pattern which results from the stimulus of the wavelengths themselves was never realized. So, yes, she does “learn” something new. Now, we could perhaps propose that Mary not only knows how to translate sensory experience into neurophysiology but also has the incredible ability to manipulate her own neurology accordingly. In this case, I would propose that the problem has gone away. Mary has induced the experience of color independent of the actual visual reception of color. She would now have the patterns of color experience encoded in her brain and will thus have created the qualia in the same way that actually seeing it would have.

Who cares?

Door to...

Good question. As I noted at the outset, it wasn’t long ago that I would have considered these musings to be pointless and absurd. What I’ve come to find, however, is that this all actually plays a significant role in the God debate. Why? Because if some type of realism is true, and it can be said that even some small subset of abstract objects or universals exist on their own, then we have accepted the independent existence of the immaterial. This in itself is not necessarily troublesome for the naturalist position. After all, science is in the business of discovering new aspects of “nature” that were previously mysterious. There does seem to be a difference this time, though. If these things exist, and we know about them, then the implication is that we have accessed them in some non-empirical way. This accessibility elevates the mind to a privileged position which gives it access to things in a way that isn’t found anywhere else in nature. Furthermore, the current reckoning of the naturalist position would infer that this special access came about as the result of blind evolutionary forces acting on material that didn’t yet have any interface with these things. Is that just a coincidence?

To the theist, this is the gateway to further interrogation into the immaterial realm (God, soul, spirit, free will, etc…). To the naturalist, this is a crack in the door that was supposed to have been closed. While it may not serve as evidence for God, it would suggest that there is more to reality than the naturalist is typically willing to grant. There’s no telling what all lies behind that door. Of course, this potential conflict is no reason to avoid the questions and shun sensible answers. We should pursue truth wherever it may lead.

With that in mind, you may have noticed that I have skirted some of the big questions. I am ending this two part series having merely outlined my perspective on what is means to say that something exists while showing how, within the conceptualist paradigm, there does not appear to be any problem reconciling the existence of mind-dependent objects with a naturalistic account of reality. By aligning myself with conceptualism I have inferred that abstract objects exist only by virtue of their mind-dependence, but I have avoided asking whether or not some things (morality, mathematics and, of course, God) are truly mind-independent. That said, I believe that this framework presents a coherent mechanism by which we may suggest that they are mind-dependent. Even so, those will have to be addressed another time; perhaps after much more contemplation. I do not yet feel comfortable with any one position on these, among others, and this should not be a surprise. We have been debating these things for centuries. In the end, I will openly concede that a deep dive into those topics, or a persuasive refutation of my reasoning here, could potentially turn this entire framework on its head. And that is where you come in. Please, dear reader, tell me why I’m wrong.


My Ontology – Part 1: Foundations

John Stuart Mill

The tendency has always been strong to believe that whatever received a name must be an entity or thing, having an independent existence of its own; and if no real entity answering to the name could be found, men did not for that reason suppose that none existed, but imagined that it was something peculiarly abstruse and mysterious, too high to be an object of sense. The meaning of all general, and especially of all abstract terms, became in this way enveloped in a mystical haze.

John Stuart Mill in Analysis of the Phenomena of the Human Mind

Not too many years ago I probably would have placed ontological discourse under the category of “pointless and senseless blather”. I say this not to denigrate the subject matter but rather to expose the naivety with which I constructed my worldview. That said, the John Stuart Mill quote does well to capture my current sentiment. Though I still find myself bewildered by certain ontological perspectives, I cannot escape the ramifications therein and so I am obliged to make an effort to address the topic.

I think it’s worth repeating the disclaimers that I offered when I presented my epistemology:

Disclaimer #1: I have no formal philosophical training, so forgive me if I abuse the terminology and/or overlook well established points and counter-points. My goal is not to educate others on philosophy, but to work through and explain the current state of my own view of ontology. This is armchair philosophy.

Disclaimer #2: I am trying to avoid using complicated and confusing language, but that is not always easy in these types of discussions. I apologize in advance if I have failed in that endeavor. I’m almost certain that I will.

First things first

I’m not sure that I could have given you the definition of ontology if you had asked me three years ago. I am now all too aware that ontology is the branch of philosophy which deals with the nature of existence. My journey over these last couple years has introduced me to the world of the existential, a land which was utterly foreign to me before I began to question my foundational assumptions. So, when I set forth my epistemic framework some time ago (see Part 1 and Part 2) I never considered the possibility that I was doing things out of order. According to some there is a very simple explanation for why our ontology (theory of existence) must precede our epistemology (theory of knowledge). They would suggest that we must assert that something does or does not exist before we can say that we know anything about it. On the surface this seems like a fair proposition, but then I am compelled to ask how it is that we can say whether something exists, or the form of its existence, without considering how it is that we even know about that something? As far as I am concerned the entanglement between ontology and epistemology is too deep to warrant any claims that one is prior to the other. I am tempted to leave it at that but it seems appropriate to examine this further with an example.

Frequent exposure to philosophical discussion over the last few years has bred familiarity with certain ‘pet’ scenarios and examples. When it comes to ontology, it seems that tables and chairs have been favorites for centuries. I shall continue the tradition to investigate the relation between the epistemology and ontology of tables. This starts with a brief thought experiment.

Suppose a child grows up in a house where the only tables in the house are square, four-legged tables which are set up on their side. A wire is run between the legs and used to hang clothes for drying. Suppose this child is never exposed to any other use of tables. Upon discovering the neighbors sitting and eating at a four-legged table, she may or may not recognize that it is a table but, if she does, she will suppose that it is being used in a strange way. Alternatively, upon seeing a neighbor sitting at a circular pedestal table the same child will almost certainly fail to recognize the object as a table at all because (a) it doesn’t look like the tables she knows, and (b) it has no obvious utility for running wires to dry clothes even if it were set on its side.

At this point you may be wondering if I have drifted off into a confusion between semantics and ontology but I hope to link this all together, so bear with me. The point of the ridiculous thought experiment above is to see that words, like ‘table’, are a type of expression of our experience, or what philosophers refer to as ‘qualia’. To say that something exhibits the property of ‘tableness’ is to say that it is a fair approximation of past experiences with other objects that have been labeled as tables. Words give us a way to relate those experiences between each other and this is most evident where one person’s association of a word to an experience is very different from another person’s association, even if they talking about the same physical object. Our qualia of tables includes both sensory perception of the table itself (color, texture, shape, etc…) but also relational observations (how tables are used, where they tend to reside, etc…). As the number of experiences with tables grows, so does our understanding of ‘tableness’.

While we are reliant on experience to develop a concept of ‘tableness’ we also generally expect that tables exist in the world regardless of whether we ever experience them. But I contend that this expectation only exists because we have already experienced tables, or similar objects, as independent and persistent entities; our experiences enable us to comprehend what it means for tables to exist. If we ignore this, that is, if we suppose that existence can be comprehended without any relation to experience then it would seem that existence itself becomes an incoherent concept. I cannot escape the conclusion that our comprehension of the existence of tables (ontology) cannot in any coherent way be separated from the knowledge of tables (epistemology), yet our knowledge of tables (epistemology) is apparently dependent on their existence (ontology). You cannot claim one without the other. Our ontology is necessarily informed by our epistemology. Attempts to deduce ontology independent of epistemology are actually relying on epistemology while at the same time claiming to ignore it.

Disclaimer #3: Lest it should appear that I am addressing a particular work, please note I wrote and titled this section before encountering James W. Sire’s book “Naming the Elephant: Worldview as a Concept”, which contains a chapter entitled “First Things First” that is an evangelical argument for ontology prior to epistemology (and which can be read on Google books). He considers views where ontology comes first and where epistemology comes first, but never one in which they cannot be prioritized relative to each other. I guess we disagree.

Defining existence

Plato's cave

In the previous section I did not discount the possibility that ‘tables’ exist as something separate from any particular instance of a table. That is, to say that we have experienced ‘tableness’ may allow that we experienced something distinct and possibly independent from the tables themselves. I have just waded into some deep and murky waters and sanity requires that we review some definitions.

We can broadly split all ontological positions into two groups:

  • Realism: The position that something exists.
  • Anti-Realism: The position that something does not exist.

Simple enough. We typically apply ‘realism \ realist’ and ‘anti-realism \ anti-realist’ as qualifiers for a category of things (e.g., moral realist, mathematical anti-realism, etc…). For the most part this distinction isn’t very interesting until we start talking about abstract objects and universals. It is here where we open the proverbial can of worms, so I need to proceed by first defining the main categories of “things”. As it is with all philosophical language, there is widespread disagreement about definitions; and fringe cases abound. Regardless, this is what I understand to be the majority perspective:

  • Concrete Object: Something which can be located in space and time.
  • Abstract Object: An idea, non-physical representation or categorization.
  • Individual (or Particular): A singular instance of an object. (Wikipedia says that ‘particular’ is the adjective and ‘individual’ is the noun, but I find that they are actually used interchangeably in practice).
  • Universal: A quality or property which is common between individual objects.

I find it especially true in philosophy that examples are invaluable for clarifying definitions. The following table tries to offer some examples that show the relationship between the categories given above.

Concrete Objects Abstract Objects
  • The pixels in the shape of a 7 on your screen
  • My dining table
  • An electromagnetic wave with a 520nm wavelength
  • Tonight’s sunset as viewed from your house.
  • The number 7
  • The table described in a fictional story
  • The green I see in my front yard
  • The beauty of tonight’s sunset
Universals Empty?
  • Numbers
  • Tables \ Tableness
  • Green \ Greenness
  • Beauty

There are several points of contention here. The most obvious is whether anything should be categorized as a concrete universal. Somebody might also argue that “the green I see in my front yard” is just a synonym of “an electromagnetic wave with a 520nm wavelength” – but philosophers will often suggest that the qualia of ‘green’ is something different; we’ll touch on this more later. Regardless, now that we have a set of words to describe the possible constituents of reality, let’s look at the ontological positions that have historically been held:

  • Realism \ Platonism: The position that abstract objects and universals exist on their own in addition to concrete particulars.
  • Conceptualism: The position that abstract objects and universals exist only as a concept while concrete particulars exist in and of themselves.
  • Nominalism: The position that abstract objects and universals don’t exist whereas concrete particulars do.
  • Idealism: The position that everything exists only as a mental concept. In a sense, there is no “physical” world.
  • Nihilism: The position that nothing exists. No need to discuss this further then, eh?

Having laid all of these definitions out it immediately becomes apparent that there’s a huge problem: every definition relies on an agreement as to what it means for something to exist. At first blush, existence appears to be defined by the set of things which we say exists, but that type of definition will just make us dizzy (if you weren’t already). So, to start, I want to narrow down the concept of existence a bit. At the risk of confusing things further, I want to bring two more categories into play: mind-dependent things and mind-independent things. Mind-dependent things are those which are only identifiable as conceptions of the mind. Fictional characters like Paul Bunyan and Captain Kirk are clear examples. Depending on your ontological position, certain abstract objects may or may not also be examples. Mind-independent things are those which can be said to exist even if there is no mind, like Ayers Rock, the keyboard I’m typing on or the screen you are reading this on. They are “out there” and can be discovered or accessed by minds. We generally agree that all concrete particulars are mind-independent things. A moral realist would also say that morality is mind-independent and an idealist might say that nothing is mind-independent (except perhaps God).

Paul BunyanNow, to define existence, I want to examine how it is that we use the word in our everyday practice. In my experience we will generally agree that things which are mind-independent can be said to exist. The remaining question, then, is whether that completes the set of things which exist or whether there are cases in which mind-dependent things can also be said to exist (setting aside the question of which things are mind-independent). Probing this further, it is also my experience that we will generally agree that certain mind-dependent things do not exist. We will generally agree that Paul Bunyan the person does not exist, but what about Paul Bunyan the story? My intuition tells me that I should say that Paul Bunyan the story exists but that Paul Bunyan the person does not. What is the distinction? Time for another thought experiment.

Consider a scenario where the story of Paul Bunyan exists only in the oral tradition of an isolated tribe. The story is never reproduced except through verbal communication between the tribe’s members. Imagining myself as a member of this tribe, I find it very easy to say that the story of Paul Bunyan exists. Now suppose that a nasty virus sweeps through and kills every member of the tribe (and that ‘mind’ does not survive the body). Would I still say that the Paul Bunyan story exists? I am inclined to answer yes, but only because I know that it was at one time part of a mind. If you instead asked me whether the Luap Naynub story exists and could tell me absolutely nothing about it and could not even explain why you asked that question in the first place then I am inclined to say that it does not exist. The difference is that in the first case the knowledge of the story’s existence survives in my mind (even if I don’t know any details of the story – which almost certainly means its existence in my mind is vastly different than its existence in the context of the tribe) and in the second case there is no identifiable mind, past or present, in which the knowledge of the story exists. I can see no difference between mind-dependent things which do not exist and mind-dependent things which are universally unknown. I then find myself with a few options. Either mind-dependent things:

  1. Never exist (and my intuitions about the existence of the story of Paul Bunyan were incorrect), or
  2. Come into and out of existence (under an A-Theory of Time), or
  3. Exist if they ever have been, are, or will be synthesized in a mind (under a B-Theory of Time), or
  4. Always exist for all possibilities (and are “out there” waiting to be discovered).

I propose that the 2nd option is the best fit for our everyday understanding of existence, with the 3rd option as the equivalent formulation under a B-Theory of time. It appears that this definition applies equally well to mind-independent things.

OK, so what about Paul Bunyan the person? Why don’t we say that he exists? Let’s look at this through the lens of concrete versus abstract objects. The story of Paul Bunyan is a particular of the universal type “story”, and particulars of type “story” are also abstract. We are content to say that abstract objects exist as mind-dependent things, so it makes sense to say that the story of Paul Bunyan exists. However, the person of Paul Bunyan is a particular of universal type “people”, and particulars of “people” are concrete. If we say that a concrete object exists, we expect it to be mind-independent, and we have no reason to believe that Paul Bunyan the person is mind-independent (and good reasons to doubt it). This means that there is a problem if we say that Paul Bunyan the person (a concrete object) exists. The solution, then, is to say that he does not exist. Conversely, we can accept the proposal that the idea of Paul Bunyan the person does in fact exist, because now the particular is the idea (an abstract object), not the person (a concrete object).

So this is where I will settle. I will use “exist” to indicate that something is a constituent of reality even in the absence of mind (i.e., it is mind-independent) or that it is identifiable as a concept within a mind. This approach unfortunately requires that we qualify whether we are speaking of concrete existence or conceptual existence, but that is simply an artifact of language. Finally, note that the actual substance (if there is any) of abstract objects is tangent to this and can be safely ignored for the purposes of defining existence this way. If I then had to classify myself according to the ontological positions given above, I suppose this means that I am a conceptualist.

In Part 2 I take a closer look at mind-dependent things and how I think that a naturalist can plausibly account for their existence. It may be fair to say that this post (Part 1) is just a primer for the discussion there.