But that's not what has been said. What has been said is that if a proposition is true then it is justifiable. — Michael

And again, if that is no more than that it can be made the consequent of a material implication, that is trivially right. So again, what is it to be "justified"?

What has been said is that if a proposition is true then it is justifiable. — Michael

Doesn't that lead to an infinite regress of justifications?

But that's not what has been said. What has been said is that if a proposition is true then it is justifiable. — Michael

Yes. And if B then A→B, for any A or B. So if we take justification as being the consequent of a material implication then that any truth is justified is trivial.

But is that what you mean?

(do I need to add that if it is justified, then it is by that very fact justifiable?)

But you know that this is mostly crap. Realism/idealism is a false opposition.

Propositions are bits of language, so they are human... "mind-dependent" in the casual sense thrown around here. Constructed, if you like.

What is the case will often be the case regardless of what you or I believe, yet how we talk about what is the case is a construct made up by us.

That is, not everything that can be believed is true. Truth and belief are different.

SO the supposition that it's all either mind-independent or it isn't, that's simplistic shite.

It's not that things always conform to thoughts, nor vice versa.

Which is why I keep rabbiting on about direction of fit.

Everything human could be said to be mind-dependent (not that I am enamoured of the terminology).

If things existed prior to humans or any other percipient, there is no sense in which the Universe could be said to be mind-dependent (unless you posit panpsychism).

Neither of those is quite right. It's a silly argument. We do talk about how things are. Sometimes what we say is true. Sometimes not.

Neither of those is quite right. It's a silly argument. — Banno

I agree it is a silly argument in the sense that it really doesn't matter. However, for the sake of clarity, how could it not be right to say that the prebiotic Universe was not dependent on mind? Granted the saying of it is dependent on mind, but to say the Universe was dependent on mind prior to the existence of any mind is tantamount to saying that it either didn't exist or that it is fundamentally mental in nature..

how could it not be right to say that the prebiotic Universe was not dependent on mind? — Janus

This sort of question is risible. The Orion Nebula is not dependent on you, nor are trilobites. But your saying anything (thinking, believing, doubting...) about them is dependent on you.

Yawn.

But you know that this is mostly crap. Realism/idealism is a false opposition. — Banno

No it isn't, although I know from long experience it is not a distinction that makes sense to you. Which is why you keep rabbiting on about cups and saucers. That's where the simplistic shite is.

Fine, Waif.

"Everything exists within experience" is wrong. It's only experience that sits within experience. The world is not limited by you.

What was the significance of the remark Wittgenstein made 'I am my world?'

For Wittgenstein, the "world" is understood as a logical space in which facts exist, defined by the relationships between elements. When he says "I am my world," he is not referring to a literal equivalence but rather to the philosophical idea that the boundaries of a person's experience and understanding constitute their subjective world. Here he distinguishes between the "subject" as a metaphysical entity and the "self" as a part of the world. The subject, in his view, is not a thing in the world but rather a limit of the world. As he writes in Tractatus 5.632, "The subject does not belong to the world: rather, it is a limit of the world." The world, in this sense, is shaped and defined by the subject's perspective and capacities for representation. This remark resonates with a solipsistic tendency in his early thought—the idea that one's experience is fundamentally bounded by one's own perspective. However, his solipsism is nuanced: he does not claim that the external world does not exist but that it is only knowable through the structures and limits of the subject's representational capacities.

Which pretty much what I mean by it, also. (I refer to Wittgenstein because I know you're familiar with his writing.)

The realist view that most take (usually unawares) is a perspective outside perspective: seeing oneself as an individual in 'the vast universe'. But where does that perspective exist, if not in the mind?

This sort of question is risible. The Orion Nebula is not dependent on you, nor are trilobites. But your saying anything (thinking, believing, doubting...) about them is dependent on you. — Banno

You're just basically repeating what I said in slightly different words. So it seems you are agreeing with me despite your boredom.

My take is that when Wittgenstein refers to the world he is referring to the world of human experience and judgement. He's not referring to the extra-human Universe.

'I am my world — Wayfarer

Whatever it might have been, it is not "The world is me".

He stepped beyond the solipsism that traps you.

You're just basically repeating what I said in slightly different words. — Janus

Then I haven't been able to follow what you are saying.

My take is that when Wittgenstein refers to the world he is referring to the world of human experience and judgement. He's not referring to the extra-human Universe. — Janus

But again - how do you see the 'extra human universe'? Even if you're an astrophysicist aware of the vastness of the Universe, you are providing the perspective within which that is meaningful. That is also a feature of the 'umwelt' or 'lebenswelt' of phenomenology. Wittgenstein’s remark that "the subject is a limit of the world" (Tractatus, 5.632) aligns with the idea that the Umwelt represents the horizon of what a subject can perceive and engage with. The subject does not appear in the world as an object but constitutes the horizon or boundary within which the world appears.

Similarly, in phenomenology (e.g., Heidegger or Merleau-Ponty), the world is not an objective domain "out there" but is always encountered through the structures of embodied, situated being.

He stepped beyond the solipsism that traps you. — Banno

I would take that remark seriously if you demonstrated any grasp of the point I'm making. There is no way that I support, suggest or endorse any form of solipsism.

I would take that remark seriously if you demonstrated any grasp of the point I'm making. — Wayfarer

It's a trick question in philosophy. Wittgenstein talking about the world and the subject.

"The subject does not belong to the world: rather, it is a limit of the world." — Wayfarer

W stepping outside to talk about the subject. If what's he's saying is correct, then he is incorrect. It is a paradox.

It is a paradox. — L'éléphant

No kidding. Just the kind of thing that will trip up your average "realist".

Deleted for excessive sarcasm. (I'm trying to avoid it.)

The point I'm trying to make is that there is a kind of 'dual perspective' at work in understanding this question, which is deep question. There's common sense realism, in which we are just individual subjects in a vast world. But there's also the philosophical understanding of the role of the mind in constructing the world. It doesn't mean literally constructing the physical earth, but the 'meaning-world' which provides the framework for judgements about what is real.

Sure, all that; and yet we also have surprise, error and agreement. So the world is not completed by experience.

I would take that remark seriously if you demonstrated any grasp of the point I'm making.

I would take that remark seriously if you demonstrated any grasp of the point I'm making. — Banno

You appear to believe that I must insist that nothing can exist outside my knowledge of it, that, according to what I'm saying, there can be nothing new, or nothing I'm mistaken about, on those grounds. But that is not entailed by the kind of antirealist argument that I'm advocating. I am criticizing mind-independence as the criterion for what is real - what is said to exist outside of or apart from any experience. That is what I take realism to be defending.

As per the OP

1. There exist objects that are mind-independent

2. We can grasp the features of objects external to our mind

3. We can justify our knowledge of objects external to our minds — Sirius

No kidding. Just the kind of thing that will trip up your average "realist". — Wayfarer

Apologies. I thought you were one.

The point I'm trying to make is that there is a kind of 'dual perspective' at work in understanding this question, which is deep question. There's common sense realism, in which we are just individual subjects in a vast world. But there's also the philosophical understanding of the role of the mind in constructing the world. — Wayfarer

Fair enough. In so far as the use of language influences the way we see the world, then yes, the mind plays a role in constructing the world.

It just now caught my attention that there seems to be a pervasive agreement among thinkers in this forum that the way the world reaches our consciousness, which is different than the way the world actually is, constitutes an automatic error or subjectivity on our part.

When is it subjective? If the construction of our eyes is such that the cones carry the photo pigment and communicates with the brain when light waves enter, which causes us to see colors, then how is that subjective?

You appear to believe that I must insist that nothing can exist outside my knowledge of it... — Wayfarer

You introduced constructivism, as

Constructivism emphasizes the role of human activity, interpretation, and social practices in constructing knowledge, reality, and meaning. — Wayfarer

I maintain that there is stuff that is true even if we don't know, believe, or whatever, that it is true.

Do you agree?

If so, then constructivism is not the whole story.

When is it subjective? If the construction of our eyes is such that the cones carry the photo pigment and communicates with the brain when light waves enter, which causes us to see colors, then how is that subjective? — L'éléphant

It is subjective in that there is a subject to whom the colour appears. As to whether that is erroneous in principle is another question, and besides, colour perception is only a very narrow and specialised instance of perception generally - we perceive a good many things other than colours.

But other than that, the question you're touching on is the age-old one of reality and appearance - whether the world is as it appears, or different, how so, why, and so on. A good deal of philosophy (and nowadays even a lot of science) is concerned with such questions.

I maintain that there is stuff that is true even if we don't know, believe, or whatever, that it is true. — Banno

Plainly - I don't even know most of the people in my street. But that's not the point. The point is the overlooking of the fact that even so-called objective knowledge is the possession of subjects, the significance of which is not generally not considered, and who are explicitly left out of the account by metaphysical realism. Metaphysical realism insists that there are objects that are just so, the same for all observers, and that these are fundamental. Whereas the 'antirealist' is saying that how we categorise and sense these objects and interpret their meaning, is just as fundamental as the objects themselves. Constructivism may not be the whole story, but it's inextricably part of it. Realism will generally insist that 'the world' is just so, and would be just so, whether there was anyone in it or not. But as I keep saying, even that relies on an implicit perspective.

So my argument against mind independence *is not* that the entire cosmos is dependent on the existence of my mind, which is how you appear to be interpreting it.

Anyway I have to sign out for a few hours, back tomorrow.

↪Leontiskos It's in that post above. There's Hart, McGinn, Mackie, and Routley. And of course Fitch himself. — Michael

The names appear, but where is the claim that they are realists? To take an example at random: Mackie. Here is what your quote says about Mackie:

Mackie (1980) and Routley (1981), among others at the time, point to difficulties with this general position but ultimately agree that Fitch’s result is a refutation of the claim that all truths are knowable, and that various forms of verificationism are imperiled for related reasons. — SEP

How in the world do you construe this as, "Mackie is a realist who falls into my criteria for realism"?

But that's not the point — Wayfarer

It was my point.

There's also the IEP article I quoted here. Although in that specific case they consider the proposition "I am a brain in a vat" rather than the proposition "the cat is in the box". — Michael

1. If metaphysical realism is true, then global skepticism is possible
2. If global skepticism is possible, then we can be brains in a vat
3. But we cannot be brains in a vat
4. Thus, metaphysical realism is false (1,2,3) — Brain in a Vat Argument | IEP

The simplest answer here is that (3) is false. The second answer is that even if we grant (3), it then follows that (3) is not unjustifiable. That is, if it is possible to justify a (necessary!) claim about brains in a vat, then the matter of brains in a vat is not unjustifiable. I would guess that the average realist is fine with either approach, depending on how (3) is presented.

Specifically, you want to say that realism entails that <"We are brains in vats" can be true even if it is not possible to justify such a proposition>. You then go on to attempt to justify the proposition, <"We are brains in vats" is false>. Even supposing you succeed, your success would show that the putatively unjustifiable proposition is in fact justifiable, which moots the criterion of realism (per your strange/exaggerated definition).

Check out Is Reality Real?

Even if you're an astrophysicist aware of the vastness of the Universe, you are providing the perspective within which that is meaningful. — Wayfarer

Sure, but that doesn't entail that the existence of the universe depends on a perspective. You seem to be confusing or conflating two different things.

Similarly, in phenomenology (e.g., Heidegger or Merleau-Ponty), the world is not an objective domain "out there" but is always encountered through the structures of embodied, situated being. — Wayfarer

For the "world" yes but for the Universe, no—as far as I know this is not correct for Heidegger at least (who I studied extensively at one time).I believe that Heidegger acknowledges the existence of the extra-human universe, but that is not what he is concerned with when he deals with being (being-in-the-world) or Dasein.

I mean you can define existence in an eccentric way to mean something perceived, but that is not what Heidegger is doing. I doubt it is what Merleau-Ponty is doing either, but I can't be sure of that as I have not read much of his work.

For Heidegger the world is neither "out there" nor "in here". That is a false dichotomy.

But there's also the philosophical understanding of the role of the mind in constructing the world. — Wayfarer

The body/ mind doesn't construct the world it participates in co-constructing the world of human experience and judgement. there is a very great deal of the world (in the sense of the universe) that has nothing to do with the human.

For the "world" yes but for the Universe, no—as far as I know this is not correct for Heidegger at least (who I studied extensively at one time).I believe that Heidegger acknowledges the existence of the extra-human universe, but that is not what he is concerned with when he deals with being (being-in-the-world) or Dasein. — Janus

But one may be an empirical, without being a metaphysical, realist.

I don't see that you can substitute □(p → ◊Kp) for ∀p(p → ◊Kp). — Banno

Yeah, going over it again I think I misunderstood what the article was saying about the relationship between the two.

Specifically, you want to say that realism entails that <"We are brains in vats" can be true even if it is not possible to justify such a proposition>. You then go on to attempt to justify the proposition, <"We are brains in vats" is false>. Even supposing you succeed, your success would show that the putatively unjustifiable proposition is in fact justifiable, which moots the criterion of realism (per your strange/exaggerated definition). — Leontiskos

It's a simple modus tollens:

1. If realism is true then it is possible that we are (unknowably) brains in a vat
2. It is (knowably) not possible that we are brains in a vat
3. Therefore, realism is false