Shadow thread for MOA H2H Debate

[rikuoamero]

As the title says, this is a shadow thread for the Head-to-Head debate currently in progress here
viewtopic.php?t=32046

Other than this post, I will NOT interact with this thread. I merely wanted to provide a set space for discussion on the debate for other users.

[Divine Insight]

Metaphysical "speculation" has uses in the real world. Look no further than semiconductors and imaginary numbers.

Imaginary numbers are used in engineering all the time to represent actual physical quantities. So I'm not sure where why you suggest that imaginary numbers should be an example of something that is metaphysical.

If Modal Logic DEMANDS that there needs to exist ACTUAL WORLDS...

What's this about needing to exist actual worlds? There is only one ACTUAL WORLD, our world, which is one possible worlds out of many. I have no idea what misconception you have that lead to you make such a statement, with Catherine Zeta-Jones or otherwise.

How can you be sure that there is only one actual world? Physicist have been suggesting that there may be infinitely many actual worlds.

Of course, then we can get into the semantic argument of what we mean by a "world". But clearly even in Modal Logic people speak about possible "Worlds" (i.e. plural) So they are allowing that all worlds aren't considered to be the same world.

In fact, I would suggest that where you are failing to pay attention in modal logic is the difference between "Physical Possibility" and "Metaphysical Possibility".

You might think that countless universes where Catherine Zeta Jones is married to a different man in everyone of these universes is certainly a physical "possibility".

But it's not a physical "necessity". And just because it's physically "possible" doesn't mean that those actual physical universes then need to exist.

What on Earth made you think that you need to point this out? Who has ever suggested that Catherine Zeta Jones being married to every man a physical necessity?

Well the moment you claim that all those possible worlds "exist", then they must exist physically. Otherwise where do they exist? Just in your imagination? If so, then once again, that's not a very impressive logical formalism.

If you think Modal Logic is saying that those physical universes need to exist I suggest you study Modal Logic more closely. I doubt very seriously that it is demanding this. And if it does demand this then it's an extremely flawed formalism to be sure.

The question is why would you even think that I was hinting/suggesting/implying/saying anything along the lines of "physical universes need to exist."

Well, what does it mean for a world to "exist" if it only exists in your imagination. The boogeyman exists in your imagination too! Along with Santa Claus and the Tooth Fairy, etc.

What good is a logical system that allows for anything you can imagine to "exist"?

What could it ever be used to "prove" or "verify"? Nothing.

This is why Stephen Hawking has pronounced pure philosophy DEAD. And I totally agree with him.

~~~~~~

By the way, I've been thinking about what you mentioned concerning the Truth Values for the conditional statements. Of course Step #4 in the MOA end up being "TRUE". But that's only because the proposition P ends up being necessarily "False".

This is NOT what the proponents of the MOA had in mind.

Moreover, if the only way you can say that step #4 of the MOA is "True" is be recognizing that it's proposition must be false then you're still using step #4 as proof by contradiction that the MOA and its MGB are a logical contradiction.

To then proclaim that step #4 must be TRUE because its proposition is FALSE is a bit belated at that point.

You'd have to have already shown that the MGB doesn't exist to do that.

You believe that you can do that by "imagining" a world with no beings thus thwarting argument #1 of the MOA. But why choose that criteria? Why not just imagine an evil world that's not benevolent? That would work just as well. Or you could claim to simply imagine a world where the MGB doesn't exist. And then you could thwart it by simply imagining a world other than the one being proposed as a premise.

I don't see where your imagination should qualify as a proof that an argument must be false.

[Divine Insight]

I would say to that person...

Perhaps I misunderstand your question?

No, that's the kind of answer I was fishing for. Divine Insight was saying (a) "If a MGB exists in every possible world, then a MGB exists in every possible world" is somehow invalid/false because (b)" MGB does not exist in the actual world." You don't even need to be familiar with modal logic to know (a) is true. It functionally equivalent to the claim that "if a phone exists inside every house, then a phone exists in my house." No amount of phone searching could make that false.

But now you're just game-playing.

Look at the truth table:



In this case P = a phone exists inside every house
and Q = a phone exists in my house

Fine, if P is TRUE AND Q is TRUE then the conditional statement as a whole is TRUE by line #1 in the truth table.

However, if you look around in the real world and discovered that some houses don't have phones in them, AND you continue to hold that P is TRUE (as the proponents of the MOA are attempting to do), then by line #2 in the truth table the statement is clearly FALSE.

The ONLY way to get it to become "True" again is to confess that the original proposition "P = a phone exists inside every house" is itself FALSE, only then can you claim that this conditional statement is once again TRUE.

So this deals a lethal blow to the MOA.

Never mind the silly arguments you can make about whether or not the overall conditional statement is "True or False".

If the only reason the overall conditional statement is true is because "P = a phone exists inside every house" is itself FALSE, then the argument is pretty well dead anyway.

So this really isn't about the "Truth Value" of this statement. But rather it's about what is being claimed about the truth values of P and Q.

That decides whether or not the overall conditional statement is ultimately true or false.

You made it sound in your quote above like as if it's a tautology that the statement must always be TRUE. That's baloney. If that were the case there would be no point in having a truth table for it where it can actually be false in some situations.

[Divine Insight]

@ Bust Nak,

Just FYI, I fell in love with mathematics and logic at a very young age. And the conditional statement in logic was one of my most favorite logical statements. And I confess that one reason I found it to be so attractive was that it blew my mind that it would be "TRUE" if the proposition was FALSE! It took me quite a quite to wrap my mind around why that actually makes perfect sense.

But once I did, I fell in love with the conditional statement and I've been using it extensively ever since. So if you think you're going to trip me up on the conditional statement you are sadly mistaken. I know exactly what it takes for a conditional statement to be true or false.

And in the case of the MOA the proponents who are arguing for the MOA are arguing that the proposition of step #4 is TRUE. Therefore all you need to do to show that the overall statement is "False" (given their claim that the proposition is TRUE) is to show that the conclusion Q is false. And that's what I did.

The fact that this then necessarily makes their proposition FALSE too is moot at that point.

[Bust Nak]

How can you be sure that your imagination doesn't contain logical contradictions?

Simple, because such a thing is logically impossible.

I have no clue why it would be the case that our universe would be "observer created". But I can't rule this possibility out either. So I'm stuck with it as a "possible" world in so far as I can tell. And according to you if it's possible then it must exist.

Exist as a possibility, yes, this is trivially true.

Also you claim that the can still be other "possible" worlds that are not "observer created". But how can you be so sure of that? How can you know that it's possible for a world to exist that isn't "observer created"?

Simple, I know this because it is logical consistent.

This is the problem with your idea of a totally arbitrary logical system.

Woah there, what's this about totally arbitrary?

If you can claim that just anything is "possible", then according to you Modal Logic will support any arbitrary opinion you can come up with.

Firstly, no where have I claimed that just anything is "possible" at all. Did I or did I not bring up married bachelor as an example of impossibility? What is this with your constant strawman? Secondly, put your money where your mouth is - I want you to use modal logic support any arbitrary opinion I can come up with. How could it possibly do that?

I can imagine a LOT of things that are impossible!

Oh? Name one.

Just because I can imagine something doesn't mean that it has to be possible.

It does, by definition.

I can imagine floating through the universe at faster than the speed of light in nothing but bluejeans and a T-shirt. But just because I can imagine doing this doesn't mean it must then be possible.

Actually it does. It is entirely possible to float through the universe at faster than the speed of light in nothing but bluejeans and a T-shirt. We have indeed been through this, you just laugh it off.

According to YOU the MOA is perfectly fine if you take step #4 OUT of it.

Incorrect. No where have I implied, let alone state this. This is yet another strawman argument.

According to YOU all a person needs to do is be able to IMAGINE this world and it has to exist!

That much is true.

I can imagine a perfectly moral world, can you?

Yes, that's easy.

I can also imagine that all worlds are perfectly moral, including ours. All I would need to do to accomplish that is to also imagine that every immoral act I ever thought I saw was nothing but a daydream and never really happened. I can imagine that too!

Sure, what of it?

So according to you as long as I can imagineit, then it must be possible. And according to you, if it's possible, then it must exist.

Exist in your imagination. You just confirmed it.

You're never going to get anywhere with that line of thinking. You have Modal Logic all wrong if you think it can be used to support anything you can imagine.

Whatever gave you the impression that I would think that it can be used to support anything I can imagine?

Meaningless truths?

Yes, something along the lines of IF the sky is pink THEN the sky is pink. It's trivially true but useless to know.

Meaningless "truths" are exactly as described. Totally meaningless in any sense of the word.

But still true though.

So apparently you are the one who is conceding that Modal Logic produces "meaningless truths"?

Not necessarily, it can produce meaningless truths, it can also produce truths, given true premises.

That's because the latter violates the definition of the terms.

DING DING DING, we have another winner. Some things are impossible to imagine.

The problem with trying to imagine a world with no beings is that you can't know if these concepts are mutually exclusive or not.

Of course I can, I am imagining one right now.

The only possible worlds are "observer created" then it wouldn't be anymore possible to have a world with no beings than it would to have a married bachelor.

Then prove it.

Just because you don't KNOW that a world without beings is impossible doesn't mean that can't be mutually exclusive in some way that you are simply unaware of. Just like the terms married and bachelor are mutually exclusive.

I don't have to know anything about the external world to rule out married bachelor.

It sounds to me like you would just end up arguing semantics at that point.

It would be good if you familiarised yourself with the lingo to avoid arguing semantics.

Sure it does. In fact, that's exactly what it says:

2. If it is possible that a maximally great being exists, then a maximally great being exists in some possible world.

You are once again conflating existing, and existing in some other world. Why would you think existing in some other world implies existing in this world?

You could argue that in a purely metaphysical argument one would assert that this must be the case. But remember when the MOA gets to step #4 any bets that it's speaking metaphorically are OFF.

This is why step #4 kills it. As soon as step #4 is introduced the argument can no longer claim to be a metaphysical argument and thus producing a "meaningless truth" as you had referred to previously.

Not if you throw in true premises.

I've already addressed this. In Modal Logic the difference between "Physical Possibility" and "Metaphysical possibility" has been covered...

Right, so why on Earth would you think "existing in a possible world" means the same thing as "existing" fullstop, if you know this?

Proponents of the MOA appear to be trying to MIX these two without acknowledging that they have clearly stepped over the boundary to the physical limitations in STEP #4.

So what exactly?

Until they get to step #4 they could claim that they are speaking of Metaphysical Possibilities and not actual physical possibilities.

This is where their real ERROR lies.

That's not an error at all.

You are trying to claim that you can prove their argument to be false even on purely metaphysical terms because you claim you can imagine a world with no beings thus violating their argument.

Correct.

The problem is that you may as well have claimed to imagine a world that is not benevolent. That would work too.

Sure I can imagine a world that is not benevolent, what of it?

In fact, you could even claim to imagine a world where the MGB does not exist!!!

That's exactly what I did claim that - a world with no beings, is a world where the MGB does not exist!!! Why are you having such difficulty following?

If you claim that you can imagine such a world and that if you can imagine it, it must then be possible, then you can WIN ANY metaphysical Modal Logic argument by simply claiming that you can imagine something that would violate whatever they other person is arguing for.

You are forgetting that you cannot imagine married bachelor again.

You claim that you can imagine a world with no beings, and therefore such a world must be POSSIBLE!

Correct.

Sorry but that's just absurd.

You say that but you can imagine one just fine.

EXACTLY MY POINT!

You are clearly making absolutely no distinction between metaphysical arguments and physical arguments.

What ever gave you that impression?

I claim that purely metaphysical arguments are utterly meaningless. You may as well be playing the blues. You are doing nothing more than entertaining yourself.

Which is why it is important to have true premises. That's what bridge the game between purely metaphysical and reality.

The only arguments that can have any value or meaning at all are arguments about the real physical world. And the MOA DEMANDS that is is an argument about the real physical world in step #4.

Exactly. It is about the real physical world.

I don't really see the point in arguing with you about this any further. Clearly you are mixing metaphysical arguments with physical arguments willy-nilly without acknowledging the difference between them.

That's simply not true. Record will show that I said metaphysical necessities are physical necessities. Nothing willy-nilly about that.

Just because you think you can imagine something doesn't mean that your imagination doesn't contain logical contradictions.

Many people believe that they can imagine a "Perfect Circle" or even a line that is an actual continuum. But in truth you really can't imagine either one of those things because they both require logical contradictions in order to exist ANYWHERE, even within your imagination.

Perfect Circles are entirely possible, why on Earth would you use that as an example?! I want to know what logical contradictions you have in mind.

So just because you think you can imagine something doesn't mean that the thing you believe to be imagination can actually exist without logical contradictions.

What's this about actually existing?!

I posted the TRUTH TABLE for conditional statements. What more do you want?

I want you to retract your claim that step 4 is false. Can you do that?

There's only ONE WAY a conditional statement can be false. There are THREE ways it can be true.

Right, so fill in the truth table for "IF MGB exist in every possible world THEN it exist in this world."

Here, let me give you a head start:

Code: Select all

MGB exist in every world | MGB exist in this world | MGB exist in every world -> MGB exist in this world
-------------------------|-------------------------|----------------------------------------------------
         TRUE            |          TRUE           |
         TRUE            |          FALSE          |
         FALSE           |          TRUE           |
         FALSE           |          FALSE          |

In which instances would that conditional statement be false?

[rikuoamero]

[Replying to post 94 by Bust Nak]

Oh? Name one.

I'll give this a try...how about reversing entropy?

[Bust Nak]

I'll give this a try...how about reversing entropy?

That's not even physically impossible. Adding energy to a system can reverse entropy. More to the point - I am looking for examples of things you can imagine that is logically impossible. Things along the lines of square circles and married bachelors.

[Bust Nak]

Imaginary numbers are used in engineering all the time to represent actual physical quantities. So I'm not sure where why you suggest that imaginary numbers should be an example of something that is metaphysical.

Because there the root of a negative number exist only in the imagination. If that qualify as non-metaphysical, then neither would modal logic.

How can you be sure that there is only one actual world? Physicist have been suggesting that there may be infinitely many actual worlds.

Physicists have been suggesting that there may be infinitely many actual universes. If they are correct, then these infinitely many actual universes exists in the one and only actual world.

Of course, then we can get into the semantic argument of what we mean by a "world".

There ought not be any arguments, it's standard language used in logic. Any semantic argument would be the result of your unfamiliarity with logic. It's best if you just adopt the language instead of arguing about it.

Well the moment you claim that all those possible worlds "exist", then they must exist physically.

Why on Earth would you think that?!

Otherwise where do they exist? Just in your imagination?

Of course. Where else would Catherine Zeta Jones be your wife?

If so, then once again, that's not a very impressive logical formalism.

First order logic is not impressive either, it's not there to impress you, it's there to aid our reasoning.

Well, what does it mean for a world to "exist" if it only exists in your imagination. The boogeyman exists in your imagination too! Along with Santa Claus and the Tooth Fairy, etc.

What good is a logical system that allows for anything you can imagine to "exist"?

It lets you formally reason about possibility. Pretty useful.

What could it ever be used to "prove" or "verify"?

Possibilities. Things like IF it rains THEN I would need my umbrella; it is possible for it to rain today, therefore it is possible for me to need my umbrella today. You may say that's trivial, and I would agree, but that's what modal logic formalises.

By the way, I've been thinking about what you mentioned concerning the Truth Values for the conditional statements. Of course Step #4 in the MOA end up being "TRUE". But that's only because the proposition P ends up being necessarily "False".

Thank you very much, it only took a week to get that out of you. Like getting blood from a stone.

This is NOT what the proponents of the MOA had in mind.

Not my problem. I am not a proponent of the MOA.

Moreover, if the only way you can say that step #4 of the MOA is "True" is be recognizing that it's proposition must be false then you're still using step #4 as proof by contradiction that the MOA and its MGB are a logical contradiction.

Not necessarily, there are other ways of showing step #4 of the MOA is true - alternatively you could show it is true using second order logic; but more to the point, why not just look at it:

If there is a sock in every drawer then there is a sock in this drawer.
If there is a car in every garage then there is a car in this garage.
If there is a sandwich in every lunchbox then there is a sandwich in this lunchbox.
If there is a book on every shelf then there is a book on this shelf.
If there is a bug in every program then there is a bug in this program.
If there is a woman on every show then there is a woman on this show.
If there is a ghost in every basement then there is a ghost in this basement.

It's so trivial that it is true by observation. You even don't need to know a thing about the entities being mentioned:

If there is a "cobite" in every "sotaz" then there is a "cobite" in this "sotaz."

You believe that you can do that by "imagining" a world with no beings thus thwarting argument #1 of the MOA. But why choose that criteria?

Because I can. This only came up because you were fixated on step #4.

Why not just imagine an evil world that's not benevolent? That would work just as well.

Why imagine one when the actual world is not benevolent? Seems a bit redundant.

Or you could claim to simply imagine a world where the MGB doesn't exist.

That's what a world with no being is - a world where the MGB doesn't exist.

I don't see where your imagination should qualify as a proof that an argument must be false.

I addressed this already, if someone complains about whether an empty world is actually imaginable, I can still point towards the fact that the MOA hinges on whether the MGB is actually imaginable or not, which renders the argument question beginning. It's asking us to accept a premise that is as dodgy as the conclusion it's trying to prove.

[rikuoamero]

I'll give this a try...how about reversing entropy?

That's not even physically impossible. Adding energy to a system can reverse entropy. More to the point - I am looking for examples of things you can imagine that is logically impossible. Things along the lines of square circles and married bachelors.

Oh I misunderstood the challenge then. Very well...I submit an omniscient being. The problem of unknown unknowns means we can never actually be sure that a being is omniscient, even if it claims to be.
I cannot conceive of an omniscient being.

[Bust Nak]

But now you're just game-playing...

...if you continue to hold that P is TRUE (as the proponents of the MOA are attempting to do)

Not my problem, I am not a proponent of the MOA. The only way for "IF P THEN Q" to be false is when P & !Q, ('!' is my preference over '¬' for the "not" operator) ie. a phone exists in every house AND a phone does not exist in this house - even a casual glance should tell you that is a logical contradiction. Or if you cannot see it, I can formalise it as:

1) Assume a phone exists in every house.
2) Assume a phone does not exist in this house.
3) If a phone does not exist in this house, then a phone does not exist in every house.
4) A phone a phone does not exist in every house.
5) 1 & 4 is a logical contradiction, therefore one or both of the assumption above is false.

Therefore !(P &!Q), therefore P->Q.

If the only reason the overall conditional statement is true is because "P = a phone exists inside every house" is itself FALSE, then the argument is pretty well dead anyway.

Seriously, is the fact that there isn't a phone in every house, the ONLY reason you can see for accepting that "IF a phone exist inside every house THEN a phone exist inside this house?"

You made it sound in your quote above like as if it's a tautology that the statement must always be TRUE.

I AM saying that, the statement must always be TRUE.

If that were the case there would be no point in having a truth table for it where it can actually be false in some situations.

According to the truth table, in what situations would "IF a phone exist inside every house, THEN a phone exist inside this house" be false? Be explicit. Next question, are those situations possible? In short, could you follow what I stated above?

...And in the case of the MOA the proponents who are arguing for the MOA are arguing that the proposition of step #4 is TRUE. Therefore all you need to do to show that the overall statement is "False" (given their claim that the proposition is TRUE) is to show that the conclusion Q is false. And that's what I did.

The proponent of MOA say P, you say !Q, therefore P & !Q, therefore !(P->Q)? Nevermind the fact that P->Q? That's why I jumped on you in the first place, it's illogical.

P->Q is always TRUE, where P= MGB exists inside every world, Q=MGB exist inside this world.

[Bust Nak]

I'll give this a try...how about reversing entropy?

That's not even physically impossible. Adding energy to a system can reverse entropy. More to the point - I am looking for examples of things you can imagine that is logically impossible. Things along the lines of square circles and married bachelors.

Oh I misunderstood the challenge then. Very well...I submit an omniscient being. The problem of unknown unknowns means we can never actually be sure that a being is omniscient, even if it claims to be.
I cannot conceive of an omniscient being.

It seems I was still not clear enough. I am looking for things that are logically impossible, and yet conceivable. Here you say you cannot conceive of an omniscient being.