It's fine to say "P is true if P corresponds with reality," but then we need to ask, "Okay, how, exactly, does that obtain? How, exactly, does a statement correspond with reality." And the answer to that is that a person makes a judgment about it. — Terrapin Station

Words have their referents in reality. Once it is chosen which words refer to what in reality, it is an objective fact whether a statement made of those words corresponds to reality (accurately describes reality), not a matter of subjective judgment. If you jump out of window you will fall, no matter what anyone's judgment may be.

But a statement is true if it corresponds to reality. It is irrelevant whether anyone subjectively judges it as true.

Do you think there is no objective truth? No external reality?

It can't mean that there are 4 of one world and 1 of the other, since four of them would be identical, and thus violate the law of identity. — noAxioms

You can have copies of a world that are the same as that world. Their only difference would be their different position (place) in reality.

No. Propositions are the (meanings of) the statements. — Terrapin Station

Propositions are the meanings of statements, that is, the referents of statements in reality.

Take the proposition "There is no unicorn on Main Street". The proposition is true in our world, so it is a property (characteristic, feature) of our world. On the other hand, the proposition "There is a unicorn on Main Street" is false in our world, so it is not a property of our world. Maybe it is a property of some other world.

The proposition "A circle is not a square" is a tautology because it is true in every possible world, so it is a property of every possible world. On the other hand, its negation is false in every possible world, so it is not a property of any world.

I don't agree that "reality itself" issues propositions. It's something that individual persons do. — Terrapin Station

Propositions are a kind of properties of reality. People's statements refer to these properties.

Joe's not saying anything about a unicorn not existing on Main Street, is he? So where is a proposition that a unicorn doesn't exist on Main Street coming from? — Terrapin Station

It is coming from the same source as the proposition that a circle is not a square: from reality. Every thing exists in the sense in which it is defined (constituted, placed) in reality. Unicorns don't exist on Main Street; it's part of their definition.

But it illustrates a point: Objectively, there seem to be no hard rules to be violated. I have a hard time justifying a four-sided triangle, but it presumes that three is not identical to four. Pretty obvious, but is that true given no rules at all? — noAxioms

"contradictory statements cannot both be true in the same sense at the same time"
https://en.wikipedia.org/wiki/Law_of_noncontradiction

So if in one sense you mean wheels only as those on which the car currently travels and in another sense also as a spare wheel, your statement about the wheels is consistent. A contradiction arises only when something is asserted and denied in the same sense.

In arithmetic, four is not identical to three. It is the successor of three. So to claim that four is identical to three in the arithmetical sense is a contradiction.

So if all these outcomes exist, why do empirical measurements find more occurrences of the probable ones than the improbable ones? — noAxioms

The only reason I can think of is that the more probable outcomes occur in more worlds than the less probable outcomes. But I heard that this is still an unsolved problem in MWI because it is not clear how to calculate frequentist probabilities when there are infinitely many worlds. Maybe the number of worlds that split at a measurement cannot be infinite. Maybe a unified theory of QM and gravity will give the answer? (just my lay speculation)

The other solution is that some realities are more probable than others, and in the case of your proposed view, it means some things are more logically consistent than other things. This world exists more than the possible but more improbable ones. — noAxioms

I don't know what it would mean that some things are more logically consistent than others.

Okay, so sticking with the unicorn example, what's the proposition that's both being asserted and denied unequivocally? He's not denying "There is a unicorn on Main Street." So what proposition is both he asserting and denying? — Terrapin Station

It is contained in the definition of a unicorn that it doesn't exist on Main Street (at least in our world), just as it is contained in the definition of a circle that it is not a square. So the idea that a unicorn exists on Main Street says that something that doesn't exist on Main Street exists on Main Street.

You're not getting the square circle thing right, first off. The issue there isn't the shapes. It's the idea of constructing a square equal in area to a given circle. — Terrapin Station

I said nothing about the area of a circle or a square. I said a circle is a square, which is a clearly inconsistent statement. The statement "There is a unicorn on Main Street" is inconsistent too, even though it may not be obvious.

Anyway, note that I'm not claiming that someone can not have an inconsistent belief. So jumping to other examples isn't very useful. — Terrapin Station

The example about the circle is similar to the example about the unicorn, only in the unicorn example the inconsistency may not be obvious. So I wanted to show the parallels. Joe's idea is inconsistent no matter whether he believes it. If he believes it then his belief is inconsistent too.

So you would say that Joe's idea that a circle is a square is consistent?

How would you state a specific example of P & ~P re the idea? — Terrapin Station

Joe has the idea "There is a unicorn on Main Street". He may not know that there is no unicorn on Main Street, but his not knowing it doesn't make his idea consistent. He may only be aware of "There is a unicorn on Main Street" but his idea is de facto "There is a unicorn on Main Street & there is no unicorn on Main Street" (because there is in fact no unicorn on Main Street).

He might as well have the idea that a circle is a square without knowing that a circle is not a square, but his not knowing it doesn't make his idea consistent. He may only be aware of "A circle is a square" but his idea is de facto "A circle is a square & a circle is not a square" (because a circle is in fact not a square).

If Joe believes that there's an extramental/objective unicorn on Main Street, then we could say that he "defines" as his idea that there's an extramental/objective unicorn on Main Street. — Terrapin Station

But his idea is inconsistent, because it is about an inconsistent thing (a unicorn on Main Street).

It seems to leave completely empty the question of if something exists. — noAxioms

A consistent something, whether it is abstract or concrete, exists. An inconsistent "something", whether it is defined as concrete or abstract, doesn't exist (is nothing).

I own a four wheeled car with five wheels. Does my car not exist? — noAxioms

Of course it doesn't. You just defined a concrete inconsistent "thing".

Now if logical consistency is equated with ontic existence, then the unicorn exists. Does 'instantiation' also mean that same thing? — noAxioms

I am not sure what you mean by "instantiation". I mean the instatiation to be the relation between an abstract (general) thing (property) and its instance, for example between red color and a particular red thing. Both the red color and the particular red thing exist.

No one is defining a unicorn as "not being what it is" though. — Terrapin Station

If someone imagines a unicorn existing on our planet, then they define it inconsistently, even when they are not aware of the inconsistency. They define it as existing in a place where it doesn't exist, and thus as something that is what it is not.

Whenever you have an idea of a thing, you define that thing. You define what that thing looks like, its properties, its parts, its environment etc.

What would be inconsistent about that? You must be defining "inconsistent" in some unusual way. — Terrapin Station

An inconsistent idea defines something as not being what it is. For example the idea of an apple that is not an apple. That's why it has no referent in reality.

Only if you're conflating an objective unicorn with a subjective idea of a unicorn. — Terrapin Station

An inconsistent idea is a collection of thoughts/qualia that doesn't refer to anything in reality. The collection of thoughts/qualia itself is consistent and exists as a mental thing.

What doesn't exist is the extramental/objective unicorn.The idea of the unicorn is logically consistent insofar as it goes though. — Terrapin Station

If the idea requires environmental conditions that are inconsistent with the existence of a unicorn then the idea is inconsistent.

So you made no claim about a unicorn existing in external reality? Then there exists just a picture of a unicorn in your mind. It is consistent and exists as a mental thing.

You defined the unicorn as existing in external reality (according to an imagination) and at the same time you said that it doesn't exist in external reality.

First sentence is an assertion. Why should I accept that to be is the same thing as logical conherence? — Chany

Because there seems to be no fundamental difference between logical possibility and existence. All logical possibilities exist in the sense that they have an identity and therefore they are not nothing. To deny existence to selected logical possibilities would be arbitrary, without a fundamental reason. Instead we can talk about various kinds of existence - spatio-temporal, abstract, mental etc.

The concept of unicorns is logically coherent. — Chany

But if you suppose that the unicorns exist in a place, for example on our planet, where the conditions are inconsistent with their existence (the requisite genes have not evolved here), then the concept of unicorns existing on our planet is inconsistent.

If the conditions on our planet were consistent with both the existence and nonexistence of unicorns then both scenarios would exist - but in different worlds, because it would be inconsistent for these scenarios to exist in the same world.

You would have to embrace multiverse theory and say that every single possible world is a real world, as real and concrete as the actual world. — Chany

Indeed, that's what I am doing.

This leads to a contradiction, as it is also logically coherent (possible) that only the actual world exists and that the other possible worlds do not exist (or if they do exist, as mental objects only). — Chany

If the other worlds are consistent then they exist, and it is not possible that they do not exist. In the second part of my paper I elaborate that the principle of logical consistency entails the existence of relations between things and that there are three logically necessary relations: similarity, composition and instantiation. With these relations you can consistently define many worlds and their copies.

You're using "it" there as if the thing in question exists and has properties. It doesn't beyond something we're imagining. So it doesn't have an inconsistent set of properties a la "it exists and it doesn't." — Terrapin Station

You define the thing as "existing where it doesn't exist"; such a definition is contradictory, it defines an inconsistent thing and that's why such a thing doesn't exist. It is not that there exists a thing that has an inconsistent set of properties, it is just you attributing an inconsistent set of properties to a thing.

How can a physical object be logically anything? Logic applies to statements, not things. — T Clark

An object is logically consistent iff it is identical to itself and different from other objects.

I don't know what that means. Is a four-sided triangle not what it is or is it what it's not? — T Clark

A four-sided triangle is a triangle that is not a triangle (because a triangle has three sides). In this sense it is inconsistent.

What would it mean for the moon not to be what it is? — T Clark

It would mean for the moon not to be a moon. Of course, that's an absurdity and that's why such inconsistent "things" cannot exist.

It almost sounds like you're saying that existence is dependent on consciousness, but I don't think that's what you mean. — T Clark

Right, existence is about things, their identities.

Do abstract objects (the form of square) exist? — Chany

They are difficult to imagine/visualize and cannot be interacted with, so they are ontologically controversial. But they seem to be a necessary part of logic, and especially in mathematics they can be clearly and consistently defined, so I regard them as real entities. In my paper I regard the instantiation relation as one of the three fundamental, logically necessary relations in reality.

Do unicorns, in some ontologically relevant sense, exist? — Chany

If they are consistent, they exist. Apparently not on our planet.

I thought you had equated existence to 'logically consistent', not to 'something, not nothing', which is a weaker, circular definition. — noAxioms

That which is logically consistent has an identity and so is something. That which is logically inconsistent does not have an identity and so is nothing. We may speak of an inconsistent thing as of "something", but due to the absence of identity it is not really something or a thing.

If existence is consistency, then the consciousness is not evidence unless it can be shown to be consistent. The fact that they've named 'the hard problem of consciousness' implies that the self-consistency of it is in question. — noAxioms

Consciousness is difficult to explain but that doesn't have to mean it is inconsistent. I think qualia of consciousness could be intrinsic identities of things, as opposed to structural/relational identities of things, and that's why they are indescribable and yet related to other things (correlates of consciousness). I elaborate it in my paper An outline of reality.

Now picture two of those persons, identical, except one instantiated, and the other not. What would be the difference between the thought processes (consciousness) of the instantiated one vs. the uninstantiated one? — noAxioms

If it is consistent for a property to be instantiated in a thing then it is instantiated in that thing (because consistency = existence). If a property is not instantiated in a thing then it is inconsistent for that property to be instantiated in that thing.

Is 2+2 objectively equal to 4, or does the arithmetic require instantiation for the sum to be true/performed? — noAxioms

I think a property (abstract entity) would not be a property if it was not a property of something. In other words, uninstantiated properties are a contradiction, and so they don't exist.

Sorry, I didn't completely answer your question about properties of an inconsistent thing, but I named some of the lowest positive real number. Those properties still seem valie, even if they lead eventually to inconsistencies. If the inconsistencies are subtle enough, the nonexistence of the thing might not be so clear. — noAxioms

Yes, but whether the inconsistencies are clear to someone is ontologically irrelevant.

A couple of weeks later you ask me "can a four-sided triangle exist?" I don't say "No, a four-sided triangle can't exist." I don't say "That's inconsistent." I say "You've broken the arbitrary rules of the geometry game." — T Clark

Whatever rules you make, if they refer to reality they cannot say that something has and in the same sense doesn't have three sides.

Reality is made up of our perceptions. If we want to change our reality, we need to first change our own perceptions. Once we change our perceptions, we change our reality. — ArguingWAristotleTiff

But our perceptions are created from information that comes to our senses from external reality, no? So there is also an external reality that is the source of our perceptions.

What we imagine, exists in our minds, as thoughts or mental images. But if we imagine that some thing exists in some place in external reality where it doesn't exist, then this thing is not consistent. It may seem consistent to us because we don't know all the details of that thing or of its environment. But the thing is inconsistent, because we attribute it existence where it doesn't exist.

You might say that it would be consistent for the thing to exist under different conditions, but then you can't argue that the nonexistence of the thing under present conditions is a proof that a consistent thing can be nonexistent. Under present conditions, the thing is inconsistent - and that's why it doesn't exist.

Well, people in history questioning their own existence (Descartes most famously) cannot start from a begging position of considering nonexistence absurd. Why ask the question if you know what the answer is going to be? — noAxioms

I never really asked myself the question if I exist - I take my existence for granted. The reason I take it for granted is that I am conscious (consciousness) and consciousness is something rather than nothing, so it exists. Regarding the existence of my body, I am not 100% sure because it might be an illusion in my consciousness and I am not totally certain that the body is necessary for my consciousness. But there seems to be a lot of sensory as well as rational converging evidence that my body exists too, and in that case the body must be logically consistent too.

An inconsistent thing doesn't exist, but it still seems to have properties, so having properties is not proof of existence. — noAxioms

How can something that doesn't exist have properties? There is nothing that would instantiate those properties.

I didn't read through it yet, but from your abstract, I disagree with taking existence and logical consistency to be identical. I'm fine with saying that existents are logically consistent with respect to how you're defining logical consistency, but I don't agree that the two are identical. — Terrapin Station

And what is the difference between a logically consistent thing that exists and a logically consistent thing that doesn't exist?

Can you be more specific? The paper addresses many things.

I didn't assert existence yet. Suppose I am self-contradictory and thus don't exist. I am not identical to myself then, but how would I know that? — noAxioms

I assert at the beginning that existing things must be consistent because it seems absurd to me that an inconsistent thing (such as a four-sided triangle) could exist. So to suppose that I am self-contradictory means to suppose that I don't exist, which is absurd.

Your statement above presumes the existence of the inconsistent thing. — noAxioms

On the contrary, I presume that inconsistent things don't exist.

If I (or my universe context) was self-contradictory, what test for that might there be? — noAxioms

I think it would be absurd if there existed something that is not identical to itself, or something that is not different from other things. So your existence is a guarantee that you are consistent with all reality, even though it is in practice impossible for you to check the consistency of your relations to all your parts, properties, and everything else.

We don't think entirely differently, do we? If no world has it, then it is logically impossible. If this is a uni-world sort of physics (non-MW interpretation), then hard-determinism is what makes the alternative with the button an impossible thing. — noAxioms

Yes. Although it doesn't seem to be inconsistent for there to be parallel worlds.

AF(F(Vulcan) <-> F(Vulcan)) is tautologous.
Therefore, Vulcan exists ??? — Owen

It depends on whether Vulcan is consistently defined. Does it have a consistent identity? If not, then it has no identity and it makes no sense to say that it is identical to itself. So we have to examine what properties the presumed Vulcan has, what parts, if any, it has, and whether these properties and parts do not contradict each other or whether they do not contradict the environment in which they presumably exist.

Wouldn't something nonexistent be identical to itself? Take the smallest postive real number, or javra's dfjsl-ajf'l, something not logically possible (mostly due to that four-sided triangle bit). — noAxioms

A nonexistent has no identity, so I don't think it makes sense to regard it as identical to itself. The definition of a four-sided triangle, for example, denies that the triangle is a triangle; it denies its identity. It refers to nothing. All contradictory definitions refer to nothing.

How about the 'like' button on this forum. It seems not to exist, but it is logically consistent, and identical to itself. Perhaps it exists, but is not present in the context of the features of this forum. Were it not to exist at all, I could not complain of the nonexistence of it in this context. — noAxioms

Maybe the existence of the 'like' button on this forum is logically consistent, but obviously its nonexistence is logically consistent too. If both scenarios are consistent then they both exist - but in different worlds (contexts), because it would be contradictory if the button existed and simultaneously didn't exist in the same world. We happen to live in a world where the button doesn't exist, but perhaps our copies in a different world (which is a copy of our world) can enjoy the button.

Interestingly, the naming of it creates it. To physics, it is all just particles and events and relations, but the grouping of them, extended in spacetime, is encapsulated by the name 'candle', which has meaning to the user of the language. — noAxioms

I wouldn't say that naming something creates it. The candle is objectively there, as a collection of atoms. Just because we find this collection interesting enough to give it a name doesn't mean we created this collection by naming it.

Thank you for this different definition, which admittedly seems not to reference a context, but is one implied? — noAxioms

Every thing must be differentiated from other things, so those other things provide a context. But I mean the word "context" in the sense of "all other things". Those other things need not be just outside a whole but also inside the whole - the parts of the whole. Because the whole is also different from its parts.

Not according the to model of spacetime which breaks down and thereby leads to the inference of a gravitational singularity. — javra

If the model is inconsistent then it is not an accurate representation of reality, because reality cannot be inconsistent. I am talking about reality, not a model. Apparently there is spacetime in reality and there is a Big Bang at the beginning of our universe.

Are you saying there is no universe? — javra

If by universe you mean the collection of all existing things then there is no universe in this sense. Why? Suppose there is a collection of all existing things. Then this collection is a thing too, and another collection can be defined in which this thing is included as a part, so what you supposed to be a collection of all existing things is in fact not a collection of all existing things.

If by universe you mean all existing things then there is universe in this sense but it is not a single thing.