Well i have been having a discussion with a theist and he has just brought up the modal ontological argument. I have now done some research on modal logic and have sites marked to further educate myself on it, but i am still way to new to it to have any clue whether my argument holds water or not, and i would really apreciate some help.
the argument he used goes like this
"1. It is possible that a maximally great being exists.
2. If it is possible that a maximally great being exists, then a maximally great being exists in some possible world.
3. If a maximally great being exists in some possible world, then it exists in every possible world.
4. If a maximally great being exists in every possible world, then it exists in the actual world.
5. If a maximally great being exists in the actual world, then a maximally great being exists.
6. Therefore, a maximally great being exists."- him
to which, after very little research i replied with
"Now the modal ontological argument is not proof of anything .The modal ontological argument applies a string of logic but fails to test the logic. If the same string of logic can be used to come to an opposite conclusion, then the logic has been disproven through contradiction.
1) It is possible that a maximally great being does not exist.
2) If it is possible that a maximally great being does not exist, then a maximally great being does not exist in some possible world.
3) If a maximally great being does not exist in some possible world, then a maximally great being does not exist in any possible world.
4) If a maximally great being does not exist in every possible world, a maximally great being does not exist in the actual world.
5) If a maximally great being does not exist in the actual world, then a maximally great being does not exist.
6) Therefore maximally great being does not exist.
This uses the exact same logic to reach an opposite conclusion that is at odds with the original conclusion. This proves that the logic of the MOA is completely faulty and as such, illogical."-my reply
To which he replied
"The issue I hold that you does not effectively deny the rationality of there existing God. Here I would re-enter the absence of evidence ,does not, = evidence of absence argument. Due to the nature of the atheist's presuppositional base for the arguments against the existence of God, it undermines the evidences that are provided for the existence of God because to say there is no evidence for the existence of God suffices to say that the atheist's knows all possible proofs that God exists, which is logically absurd. This is what I meant with my ontological argument as a preface for the evidence of absence. There is enough rational proof for the existence of God and that's where Plantinga's argument comes into play. Philosophically, it is possible. Yes, you can flip the logic but I don't believe that's sufficient enough to prove the argument holistically false. The difference here is I am saying that a maximally great being is necessarily possible and not simply possible. The reason for providing Plantinga's argument in the first place is because I am meaning to exhibit that there are no logical objections to the maximally great being unless the objector can prove that to be false. Rendering us back to premise 1. that it is possible. " - hes reply
Now this is where i am at the moment. now form my limited understanding it seems the major problem with this argument is that it uses two different meanings for the word possibility and only gets away with this argument by confusing them. the one type of possibility has to do with something that is either true or false but which the laws of logic cannot say one way or the other . such as the possibility england will win tomorrows rugby match.
The other possibility seems to be a logical possibility, something that has always been either true or false and always will be either true or false and so then has to be neccesarily true or false. and the only reason we can call it a possibility is because we do not have the answer yet.
Now this is what i have come up with so far to answer back to what he replied just and i would like to know if it is valid or not
" what i am saying is that this argument proves nothing. lets us replace god with some other proposition which is possible and if true is neccaserily true for all possible worlds , but that we do not know the answer to. lets call it (x) and (x)= the statement that the 12 billionth and first digit of pi is a 7. now we dont know the answer so it is possible that (x) is true , and if true in any world it would be true in all worlds,so if true it is neccaseraly true. now i will use your exact same argument
1. It is possible that (x) is true
2. If it is possible that(x) is true , then (x) is true in some possible world.
3. If (x) is true in some possible world, then it true in every possible world.
4. If (x) is true in every possible world, then it true in the actual world.
5. If (x) is true in the actual world, then (x) is actualy true
6. Therefore, (x) must be true
Now we do not need to know the actual answer to be able to say this does not prove (x) is true. yes it is possible (x) true, there is a 1/10 chance it is, but this does not prove it is true and we do not need to be able to prove (x) is untrue to be able to say this does not prove anything."
Now this seems fine to me and the only objection i can think of is if , in modal logic, it is possible for worlds to exist where logical and mathematical truths are not true any longer. ie if there is a world where 2+2=563 or something
But so far I'm not buying this argument.
But it's not a question of buying the argument. None of us buys the argument. It's a question of whether your critique is valid when it comes to the argument. It's not. Because you're ignoring the modal logic concepts on which the argument is based.
It's as if someone were to argue that 1+1=3 and you replied with a critique that said "That's not accurate because you first need to stipulate what color 3 is." While it IS true that the argument is false, your critique of it has no merit.
One concedes my point because, lets be honest, how can you even claim something is *possible" if you cannot define *what* it is that you are claiming is "possible"?
This is what I'm talking about...
On modal logic, the assumption is that we are talking about possible worlds already. There is NO need to back up and question whether the world is possible. The argument doesn't stand or fall or whether indeed a particular world is possible. So to insist that the a particular world needs to be defined so that you can determine whether it is in fact possible is such a fundamental irrelevancy as to render your critique without merit. It's actually less than wrong. Because if it were wrong it at least would be on same page as the argument. But it's not.
I understand the finer point you are making, but I think the objection I'm making is yet more slippery than yours.
No I don't think you do. And no your objection isn't. I'm sorry. It's not.
I am not the only one who has made objections of this type before to numerous philosophical arguments.
That some other person or persons has been ignorant of the modal logic assumptions of the argument and as a consequence has offered the same objection doesn't mean that the objection therefore has merit.
A slew of mathematical physicists have made this point time and again and that is where I first learned of it. And the type of objection is an objection related to *definition itself* and how that determines what one can say about reality
I would venture that, no, they haven't; not with regard to the modal ontological argument. And if they did they'd be just as wrong as you are.
I hope that makes more sense.
I'm afraid not. =/
What I need to hear from you to be sold is that I do not need to define the very thing I am claiming is possible in order to say it is possible
Except that's irrelevant to the argument. So... no, you don't. Not when you understand the argument.
to me this statement is utterly meaningless
And it will be to anyone that doesn't understand the modal logic assumptions of the argument.
If you have no clue what something means, you probably should not voice your opinion on it.
I'd modify this to say that you probably shouldn't voice your opinion in a way that is authoritative. You shouldn't sound more confident in your opinion than you have any right to be given your ignorance. Of course, this is often complicated because if you've misunderstood the argument then you may not be aware of your ignorance. And I think that's what's going on here. Some of the critiques aren't taking into account modal logic because so few people are aware of it or know enough about it that they can recognize it when they see it and apply it in their critique of the argument.
Also, if the experts think an argument is serious and you are not an expert and think it is easily defeated, you are probably dead wrong and just don't understand the topic.
I agree. But then to apply this advice you'd first have to be aware that experts think an argument is serious. And someone without any knowledge of modal logic is perhaps unlikely to know this.
This may sound condescending, but non-experts simply have no place openly dismissing concepts from a legitimate field of study.
And here's the same issue. Few people without some knowledge of modal logic will know that arguments using modal logic are representative of a legitimate field of study. Because, let's be honest, even with a bit of knowledge of modal logic, because of the counterintuitiveness of the implications of S5, there's still something inside you that goes "Wut? C'mon! You can't be serious!" LOL
Nevertheless, I do agree that there's enough in the discussion so far that should caution a person from ending their post to tell the person they're addressing "You can just copy and paste my critique as your own!" That's being way, WAY overconfident given the concepts under discussion.
"Few people without some knowledge of modal logic will know that arguments using modal logic are representative of a legitimate field of study."
Just reading this thread made my phreakin' head hurt! I am completely ignorant about a lot of subjects and modal logic is there at the top.
But I do have one simple honest question: Are there practical applications for modal logic? If so, what would be a layman's example? Thanks.
Don't think that you're alone in having your head hurt reading modal logic. LOL.
Not practical applications I wouldn't think, no. At least not one I can think of. It's all philosophical and academic.
Also computer science to an extent I think. I'm pretty sure it's the Matrix.
LOL. Right. My mistake. :)
"...or you take the red pill and I show you how modal logic works. The choice is yours..."
I'll send you a message about the modal logic. Sounds interesting.
Aside from the fact that what you just typed is at least semantically incoherent and makes patently false accusations about what I said, your entire critique is self defeating.
You are trying to attack logic with logic. If you succeed, you undermine logic and your argument's logical underpinnings are wrong. Therefore, it fails. If you try to retort with logic, you are admitting that logic is needed to argue, thus admitting your entire argument is wrong. QED
you can't accuse people of ad hominems because that entails formalized logic. Accusing people as such defeats your earlier post attacking logic that Nelson responded to. Also, you can not deconstruct anything without logic because it requires logic to do so.
"I disagree. I think you are trying to attack the messenger for reasons that I will let the reader observe candidly. This also sounds like an attempt to attack the messenger by implying - or just stating - that the messenger is incapable of logic. Did I misunderstand your statement?"
No, I attacked your nonsensical argument. You confused me saying "you can't use logic (meaning that if your argument is correct, then logic doesnt work)" with me saying "you can't use logic (you have some kind of mental deficiency)." I said the first and am nowhere near big enough of a jerk to say the second to anyone. I'll repeat my argument again.
"You (meaning your argument) are trying to attack logic with logic. If you (meaning your argument) succeed, you (your argument) undermine logic and your argument's logical underpinnings are wrong. Therefore, it fails. If you (any future use of logic made by another argument) try to retort with logic, you (that argument) are admitting that logic is needed to argue, thus admitting your entire argument is wrong. QED"
I am not saying "you lack the skills use logic". I am saying if your argument succeeds then the entire discipline of logic is wrong. Thus, your argument and any other which uses logic, is also wrong.
Just because someone shows why your argument is abjectly self defeating does not mean they are personally attacking you. I am not conceding anything. I showed that your argument is self defeating because it attacks its own logical underpinnings (as I just restated). I am at a loss if proving an argument is completely wrong is counted as avoiding it.
Also, your other argument is wrong about possible worlds. The point of a possible world is merely to see if something is necessary, possible, or contingent. This is a logical construct, not a physical world. Logicians use this method by stipulating only what is different. If something is like 1+1=2 is true in every possible world, then they would conclude that it is a necessary truth. Since this is a logical testing method, it does not require them to speculate about anything else. Nelson already answered this mischaracterization.
If you would like to learn about this, I recommend the following books:
1. Eric Steinhart's More Precisely
2. Ken Konyndyk's Intro to Modal Logic
3. Brian Chellas' Modal Logic: an Intro
Modal logic is so well accepted that you could pretty much open any college level logic textbook and find a discussion on it. These books are particularly easy to read though.
It should also be noted that modality is a core concept used in computer language, so if your argument is right that possible world semantics don't work, your computer doesn't work. Since your pc works, possible worlds modal logic is correct. Therefore, your argument attacking modal logic is incorrect if you can respond to this post.
"Ok, no worries about the logic thing, it just sounds to me like you're saying your "opposite number" is incapable of logic."
Where did I say that? LOL
"In reading your post I cannot find anything that addresses my objection at all. It is certainly informative and educational, but I don't see any mention of "definition", "possibility", etc. which is where I think this discussion has landed.
As for the explanation of logic, I'm sorry, but I do not understand where or how you answered my earlier question regarding this digression, if I can call it that:
... how am I attacking logic? Did I say that? Where?"
your entire argument (everything you have said) has been an attack on modal logic, which is the foundation of modern logic. Thus, if you are right, logic (which modality is the foundation to) is wrong.
Also, possible was defined. Something is logically possible if and only if it is not logically impossible (nessecarily false) in any possible state of affairs (a possible world).
or as dictionary.com put it.
|capable of being described without self-contradiction|
"but I think the objection I'm making is yet more slippery than yours."
in philosophy, slipperiness is a really bad thing. it means your argument is vague and vacuous. Thanks for the compliment.
If you understood what I am saying you would have seen that modality is the foundation to logic and computer science. Thus, you are wrong if you can post a response (computer science and modality would be right if you could and your argument wrong) or if you can even make a successful argument (your argument based on logic would mean that your argument against logic fails. -self defeating).
Who has made these objections you are talking about? If you do not name them, you are comitting a logical fallacy of appealing to unnamed authority. So who are these physicists who have disproved logic?
well what you mean by those terms is irrelevant. If your arguments are not addressing the terms as they are used by professional logicians then your argument is committing the logical fallacy of straw maning (categorically redefining words to make the opponents case into something they do not mean it to be).