However, certain of those concepts, ideas, thoughts, whatever you wish to call them, are not empirically verifiable as others are. They serve a different purpose, It's merely that we should distinguish one kind from another, and not treat them as the same or having the same function. — Ciceronianus the White

Sure, but say we wanted to know whether dragons could exist on some other planet. The first line of inquiry would be whether there is a reasonable path evolution could take to produce a creature we would consider a dragon (large reptile that can spit fire and fly at a minimum). If not, then the second line would be whether a dragon could be bioengineered within what we know of chemistry and biology.

We don't have any empirical evidence for dragons, nor do we possess the means to check for them on extrasolar planets, but we might be able to conceive of them coming to exist within known science. If so, the existence of dragons somewhere in the cosmos would be a possibility.

The point here is that dragons existing somewhere else is an intelligible proposition despite our inability to verify it (at least currently). Similarly, the number of hairs on Julius Caesar's head the moment before he died is intelligible, even though we lack the ability to extract that information from the past.

our inability to verify it (at least currently). — Marchesk

Nobody thinks that's a criterion for meaningfulness. Anyone who goes down the verificationist road will say, x is a meaningless proposition if it cannot in principle be verified.

Nobody thinks that's a criterion for meaningfulness. Anyone who goes down the verificationist road will say, x is a meaningless proposition if it cannot in principle be verified. — Srap Tasmaner

Okay, so dragons on planets too far away for us to ever visit or resolve the image to tell. For Caesar, we have no means for recovering the number of hairs on his head. Of course we can invent hypothetical ways to verify both involving time machines and warp drive, but then the verification turns into a theoretical exercise, which is not empirical.

hypothetical ways to verify — Marchesk

We could start there. "In principle" is up for negotiation.

Can you come up with a hypothetical way to verify that there really are entities you'd call universals?

Can you come up with a hypothetical way to verify that there really are entities you'd call universals? — Srap Tasmaner

I'm not a verificationist, so I'd say an argument could in principle settle the manner. According to the SEP entry, hard realism and trope nominalism are the only two candidates left standing in the debate, as all others have been shown to be untenable.

Street or Apo might have a different approach to the question that avoids the typical answers in the universals debate. My contention is that it's intelligible because we can meaningfully debate the issue (regardless of how it's approached), with the in principle possibility of resolving it in favor of some theory one day.

Can you come up with a hypothetical way to verify that there really are entities you'd call universals? — Srap Tasmaner

Actually, I don't think we have to be able to in principle determine the truth of a proposition to say it's meaningful. Universals are meaningful because the issue that gives rise to them is the discrepancy between our perceptions of particulars and the use of universals in language. How is it that we come to think and speak of the world in abstract terms? Does this say something about the nature of the world, or just our cognition or linguistic practices?

That's a meaningful question.

Actually, I don't think we have to be able to in principle determine the truth of a proposition to say it's meaningful. — Marchesk

And that just looks like choosing not to engage with the verificationist position at all. (I would add a caveat about "determining" the truth: a verificationist would at least like to know what would count as evidence, whether obtainable or not, whether dispositive or not.)

You assert that Carnap is wrong, and give what you consider counterexamples.
You assert that these counterexamples have a property M that Carnap says they don't.
Carnap asks how you know your examples have the property M?
What's your next move?

That people talk doesn't entail they're saying anything.

I think people are being disingenuous when they say they understand what the universals debate is about. My evidence for this is that when asked what it is about, they can't explain it. Ho hum.

One sign that someone understands what they're talking about is that they can paraphrase it, or put it in other words, or find different angles to come at it from. A universal, we've learned in this thread, is simply that which explains that different things have the same property. This is not a sensical way to introduce something or make it intelligible, and misunderstands how explanations work. Some other angle would be necessary to make the notion intelligible, and none is forthcoming.

My evidence for this is that when asked what it is about, they can't explain it. — Snakes Alive

Did you find the programming example lacking in explanation where you can create a class for objects which share behavior and types of properties in virtue of the class? You can also create class-level properties that all objects of that class have access to.

Classes are the role universals would play in the real world if they exist. The idea of classes and objects is inspired by our conceptualization of the world.

I never disagreed that there were groups of things that shared properties. Earlier you seemed to want something else, though, and asked the question, in virtue of what is a tiger a member of the tiger-group (presumably the desired answer is, "in virtue of a universal," though we aren't sure what's meant by that).

But as I said then, this is silly: to ask why a tiger is a member of the tiger-class is to ask why a tiger is a tiger. If this is the "problem," then it's not a very difficult one.

But as I said then, this is silly: to ask why a tiger is a member of the tiger-class is to ask why a tiger is a tiger. If this is the "problem," then it's not a very difficult one. — Snakes Alive

The simplest way to put it is that if the world consists of individuals, then how can there be a tiger class? Your answer is that they share properties. Okay, how do they share properties? What do you mean by "share"?

Why on Earth would the existence of individuals be in conflict with the existence of classes?

Why on Earth would the existence of individuals be in conflict with the existence of classes? — Snakes Alive

Because classes aren't individuals.

So your argument is:

(1) Classes aren't individuals
(2) Therefore, there can't be classes, if there are individuals?

Compare:

(1) Teams aren't individuals
(2) Therefore, there can't be teams, if there are individuals

???

(I would add a caveat about "determining" the truth: a verificationist would at least like to know what would count as evidence, whether obtainable or not, whether dispositive or not.) — Srap Tasmaner

(1) Classes aren't individuals
(2) Therefore, there can't be classes, if there are individuals? — Snakes Alive

No, there can't only be individuals. Classes are a universal concept.

No, there can't only be individuals. Classes are a universal concept. — Marchesk

I have no notion of a class except a group of individuals, or a criterion for sorting individuals into groups. Obviously, from the fact that multiple individuals exists, it follows that groups of individusls, and therefore classes, do.

What else do you mean by "class?"

I would add a caveat about "determining" the truth: a verificationist would at least like to know what would count as evidence, whether obtainable or not, whether dispositive or not. — Srap Tasmaner

I believe I only need to provide the truth condition for a non-verificationaist account of meaning. What would it mean for a verification-transcendant statement to be true?

In the case of universals, truth would be that particulars have the same properties because of universals. It could be possible to determine this truth if an argument showed that universals were necessary for particulars to have the same properties.

I have no notion of a class except a group of individuals, or a criterion for sorting individuals into groups. — Snakes Alive

So hard core nominalism. Are your groupings completely arbitrary? You mentioned before that individuals can share the same properties. I assume you group based on shared or similar properties. The class is what is common to the particulars in your group.

So hard core nominalism. — Marchesk

There is no "nominalism." These positions are all non-positions.

You mentioned before that individuals can share the same properties. I assume you group based on shared or similar properties. The class is what is common to the particulars in your group. — Marchesk

???

You can group things together however you want. It can be by a shared property, or not. It makes no sense to ask "how you group."

If the class is what is common to the particulars in the group, then you seem to be talking about a property. If so, why not speak ordinary English and refer to it as a property?

You can group things together however you want. It can be by a shared property, or not. It makes no sense to ask "how you group." — Snakes Alive

Sure, but we do in fact group things in non-arbitrary manner most of the time, and it's based on properties in common.

If the class is what is common to the particulars in the group, then you seem to be talking about a property. If so, why not speak ordinary English and refer to it as a property? — Snakes Alive

A class isn't one property, it's all the properties shared by a group. But okay, we can focus on one property. How is it that particulars can have the same property?

How is it that particulars can have the same property? — Marchesk

There is no one answer to this question. For example, tigers have a bunch of properties in common because they sexually reproduce according to a biological template. Nuts and bolts made from a factory have a lot of properties in common because they're cut according to a mold. Jokes by comedians can have properties in common because comedians have similar sense of humor, etc.

There is no one answer to this question. For example, tigers have a bunch of properties in common because they sexually reproduce according to a biological template. Nuts and bolts made from a factory have a lot of properties in common because they're cut according to a mold. Jokes by comedians can have properties in common because comedians have similar sense of humor, etc. — Snakes Alive

Alright, here is the thing. If there are properties that are the same across particulars, then there are universal properties. That means in addition to particulars, there are properties. However, we only ever perceive the individual properties. You still end up with this dichotomy between the particular perception, and the generality of properties. So you've replaced the problem of universal categories with the problem of universal properties.

If your question is about why, given that people perceive that something has a certain property, they conclude other things have it too, this is a psychological question.

If your question is about why, given that people perceive that something has a certain property, they conclude other things have it too, this is a psychological question. — Snakes Alive

So you're saying that things in the world don't actually have the same properties, we just think they do.

Also, properties "in addition" to particulars is a misleading way of putting things. A property P is just that thing you have when you're P. This exhausts the notion of a property. So when we talk about the property of being blue, and say multiple things have that property, this is the same as saying that multiple things are blue.

No.

A class isn't one property, it's all the properties shared by a group. — Marchesk

In mathematics properties are sometimes defined as the equivalence class of all objects possessing that property. For instance, once can define the class 'three' as the collection of all sets that have two elements.

This raises an interesting question: If the only green things in the universe were also glossy (as opposed to matt), and no non-green things were glossy, would we be able to develop separate concepts of green and of glossy? I suspect we would not.

The way we learn properties when we are learning language as children is by looking at examples with and without the property, and being told words for them, until we get the idea that the word for all the things with the property relates to that shared property. That learning technique (and I can't imagine any other) would not be available in a world where green <--> glossy.

It seems reasonable to me to say that in the real world as well as in maths, a universal is the set of all objects that have the relevant property.

Because our world is so richly diverse, we can always find examples where two commonly-associated properties are not shared by an object, to allow us to distinguish between the two.

The examples you use don't involve statements, though, and statements (actually, psuedo-statements) are what Carnap is addressing. Statements may be prompted by questions, of course,but are purported to be answers to them. A statement using the dragon motif would be something like "There are dragons on Neptune." We know what that means, but absent some proof, have no reason to think it's true, and good reason to believe it's not true." The result is the same with the statement "Caesar had X hairs on his head" or "No more than 278 angels may dance on the head of a pin."

It's clearly pointless to debate these statements, though not because they're meaningless. They're preposterous.

The examples used by Carnap are statements unlike those, made by a philosopher I will not name and involve what the nameless one called "the Nothing." Carnap claims statements such as those regarding "the Nothing" are meaningless, and in support notes that, first, "the Nothing" is used as a name for something, But, the one who cannot be named seems to understand that it can't be so used. His association of "the Nothing" with anxiety suggests he's using "nothing" in his own peculiar, uncustomary fashion. However, it turns out he's using it in a customary way, and that he acknowledges its use in the form of "the Nothing" is contrary to logic. He then dismisses logic and science, and states in a conclusory fashion that the superiority of science becomes ridiculous it does not take "the Nothing" seriously. "Thus we find here a good confirmation of our thesis; a metaphysician himself here states that his questions and answers are irreconcilable with logic and the scientific way of thinking."

Carnap is addressing pseudo-statements which purport to expressly say something "true" or correct, i.e. assertions, claims. It seems he's quite willing to acknowledge that statements of the kind he believes are meaningless as such may have other uses and purposes, though.

The examples used by Carnap are statements unlike those, made by a philosopher I will not name and involve what the nameless one called "the Nothing." — Ciceronianus the White

And it may very well be that Carnap is right in this case. I'm not arguing that all metaphysical statements are meaningful. However, I'm not well versed on Heidegger, so I don't know what he was trying to say there. Maybe it was like poetry.

This raises an interesting question: If the only green things in the universe were also glossy (as opposed to matt), and no non-green things were glossy, would we be able to develop separate concepts of green and of glossy? I suspect we would not. — andrewk

We can in principle, and there are real-life examples of this. One of them is ancient: a human is not [just] a featherless biped. The words we use to predicate don't just have extensions determining the individuals to which they apply. They also have intensions, mapping to extensions based on the way the world is. Coextensive terms are not necessarily cointensive, and we learn the difference based on their application, even when we have no examples of them coming apart in the actual world.