I’m confident users of this forum are capable of understanding metaphysical questions.

I agree with this; although I would say some people do take it seriously, in the sense that they are emotionally invested in reality being one imagined way or another, even though those imagined ways are not really clear conceptions of anything substantive. — Janus

It's interesting that appeals are made to emotion to explain away the existence of arguments for metaphysical positions. As if a philosopher's motivation has anything to do with the soundness of the arguments they produce. And if it does, then all argument is impugned, since humans make arguments, and humans possess emotions.

But that's a logical fallacy. It really doesn't matter what sort of emotional investment someone has in an argument, when it comes to analyzing the argument itself. The only thing that matters is wether the argument is valid, and whether it's premises are true.

There are abstract implication-facts, in the sense that they can be stated and discussed. What more "existence" should they have? — Michael Ossipoff

There are many reasons to think experience is not primary.

1. We have bodies upon which our experiences depend.

2. Our bodies were born.

3. Human bodies evolved.

4. The universe existed prior to human experience. It's also much larger than our experience.

And so on.

Is Hawking some sort of universal expert such that he can make pronouncements on the status of entire domains and declare them "dead"?

Or does he just draw media attention?

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. — andrewk

Right, so we at least recognize that the world and math have a structure such that we can classify based on relevant properties. And yeah it makes sense that we know about properties by the fact that there are different properties to distinguish between. The world appears to be both particular and universal.

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.

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.

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.

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?

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.

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 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.

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

Because classes aren't individuals.

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"?

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.

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.

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.

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.

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.

Language is an empirical phenomenon, its existence and its use are verifiable; why should its meaning be otherwise? — Ciceronianus the White

Language use is empirical. Language understanding is cognitive. We can form concepts which are not empirical. Some of these can be applied to the world in order to explain the observable.

A metaphysical question is meaningful if it's content is intelligible. I'm convinced that universals, as an example, are intelligible. They may not exist, but they are a concept with cognitive content that doesn't involve contradiction.

Yet you cannot explain what it means. Shouldn't that give you pause? — Snakes Alive

I did explain it. Also, SEP has an in-depth article on the universals debate. Russell devoted a chapter to it. Plenty of people have found it intelligible. If you don't, then I don't know what to say.

Honestly, I feel like people are being disingenuous when they use this tactic in a discussion. Not saying Carnap was being disingenuous, because he provides an argument for his position, although I think his premises are wrong.

And a good reason for thinking Carnap's premises are wrong is precisely because plenty of people find arguments such as universals to be intelligible.

those debating it do not seem to understand what they are saying — Snakes Alive

Is that because you refuse to acknowledge hat what they're saying is meaningful? Because I find it meaningful.

but not really possible to be taken seriously on its own terms (and indeed, those who debate it seem not to take it seriously on its own terms either – it's a kind of game whose playing has other edifying effects). — Snakes Alive

I don't agree with this. Most metaphysics might not have implications for daily life anymore than a math or physics problem. But that doesn't mean it isn't taken seriously by those who engage in it.

The statements of a fairy tale do not conflict with logic, but only with experience; they are perfectly meaningful, although false. Metaphysics is not "superstition "; it is possible to believe true and false propositions, but not to believe meaningless sequences of words. — Ciceronianus the White

Right, and he provides the criteria for what makes a statement meaningful. In that paper, it's anything which is logical or can be verified by experience. It's an empirical grounding of meaning.

he point is that talk of universals does not merely "have issues" – there is no body there to have issues to begin with. It's just empty. — Snakes Alive

I've done my best to explain why it's not. Universals might be rubbish on closer inspection, but they're intelligible. If not universals, then something else is needed to explain similarity.

alk of properties is part of our pre-philosophical heritage. I see no reason to think of properties as philosophers have. If philosophers want to talk about properties, it's their job to pay respect to the pre-philosophical usage, not vice-versa. — Snakes Alive

You do realize that many of the concepts from ordinary, pre-philosophical language have their issues upon closer inspection, right?

Or should philosophers just respect what the common man means by free will, for example, and not try to do any further inquiry?

They disagree with him because they dispute his definition of the word 'meaningful'. But Wittgenstein tries to show how it is not possible to accurately derive the 'right' definition for a word like 'meaningful' and so disagreements are dissolved. — Pseudonym

And where exactly does that leave us? Because it doesn't leave me agreeing with Carnap. I still find metaphysical statements to be meaningful, at least some of them.

You could do, but you have three options; — Pseudonym

Clever. I'll opt for option 3, where some metaphysical statements are meaningful. That means Carnap's might be meaningful, with the qualification that it's the only exception to it's own rule.

Now is there a way to determine which metaphysical statements are meaningful and which ones aren't? Carnap argues that meaning is determined by verification and internality to a framework. But those like me who think some metaphysical statements are meaningful will disagree with his definition of meaning.

So basically, I disagree with his starting premises.

Here's the main competitor to universals. Let me know if tropes sound any more meaningful to you:

Trope theory is the view that reality is (wholly or partly) made up from tropes. Tropes are things like the particular shape, weight, and texture of an individual object. Because tropes are particular, for two objects to ‘share’ a property (for them both to exemplify, say, a particular shade of green) is for each to contain (instantiate, exemplify) a greenness-trope, where those greenness-tropes, although numerically distinct, nevertheless exactly resemble each other. — SEP

No, because I still don't know what a universal is, and saying that it qualifies as a possible answer doesn't make it so, because I have no notion of what they are, and so no notion of what they are supposed to "answer," or how. — Snakes Alive

You do know what a category is, and you admit that particulars can have the same properties and relations. So a universal would be applying the category to the world to explain sameness.

So by "do universals exist" do you mean "can more than one thing have the same property, or be in the same relation to something else?" Then the answer is yes. — Snakes Alive

Right, so this leads to the question of what makes it so. Universals are one possible answer to that. Tropes are another. It doesn't really matter what the answer is for this discussion (I have no idea). Only whether it's meaningful.

Betrand Russell’s exposition of such topics is as close as philosophy can come to being canonical. — Wayfarer

Russell was also a top notch logician, not that it makes his argument right. But he would likely have been aware of the critiques of metaphysics.

In my lexicon other universes or events outside the light cone are metaphysics. — andrewk

Does that mean you think it's meaningless to ask if an alien civilization exists one light year outside our light cone?

What do you mean by using it in a universal manner?

Are you asking how people tell when one thing is to the north of another? — Snakes Alive

Yes, where that one thing is any thing that can have another thing north of it. That's what makes the relation universal.

The difference between these two is that it is hard to imagine any experience that would answer the question about whether universals are real, but one can easily imagine one that would answer the question about physics inside a black hole. — andrewk

And why do we need to be able to experience something in order for it to be a meaningful statement? Does all of physics include only events or things which can in principle be experienced by us? What about outside or light cone or other universes?

If you ask them whether the relation 'north of' exists, or where it is, the only appropriate answer, it seems to me, is to ask what they mean, or to comment that the question is deeply confused. — Snakes Alive

The problem is accounting for how we can use north of in a universal manner when talking about the world. As Wayfarer asked, what makes north or the natural numbers so useful when dealing with the world? Is there something about the world that makes this so?

I fail to see how that question is meaningless.

Some have made arguments that they thought were rational. I don't agree with them on that. If they were rational they would be conclusively persuasive to anybody that understands logic, regardless of that person's prior opinion on the conclusion. Yet they are not. — andrewk

Doesn't that rule out any argument that people disagree on? It would certainly rule out Carnap's, since not everyone agreed with his anti-metaphysical arguments.

It reads to me as very bad philosophy. I'm not sure I would quote that passage in support of anything. — Snakes Alive

Russell is pointing out that "north of" is a universal relation that doesn't apply to any particular situation, but rather every situation in which one thing is north of another.

The programming language above employs the concept of a universal in the form of the class Dog. Two particulars (objects) are created with unique names and weight. They share the same behavior of barking their name, weight and color. The color is also the same between them.

However, the code actually shares the bark function in virtue of the class. But the color property exists for both objects, it just happens to be the same.

This is clearly meaningful in a programming language, and examples are often taken to be modeling how we think about the world, with it's individuals and categories.

If you ask me why two things can be tigers, I could give you a causal, biological explanation; but this is apparently not what you want. — Snakes Alive

You certainly can, but you're going to have to invoke universal processes like evolution and natural selection to do so. Also genes. What is a gene? It's a mechanism for passing information for how to build organisms along. All of that involves universalist language.

However, you've said nothing about them other than that they are an explanation; hence, I don't know what they are, and so don't know in what sense they're intended to be an explanation. Hence, the question of their existence is meaningless to me until this can be answered. — Snakes Alive

We have the concept of universals in our language and thought. Tiger is an abstract concept for the individual members having similar characteristics. Even better, E=MC^2 is a universal law applying to all matter and energy in the universe.

So do we have these abstract concepts because of something in the world which isn't particular? Well yes, the similarities between things. So what is this similarity? Are the abstract concepts of our language mirroring the similarities in nature?