cnearing

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The Modal Ontological Argument Begs the Question
« on: March 23, 2016, 09:02:02 pm »
Let G be the proposition "a maximally great being exists."

By definition, then, if G exists, G exists necessarily.  Hence:

1.) G iff []G
2.) <>G iff <>[]G (from 1)
3.) <>[] G iff []G (s5)
4.) G iff <>G (from 1 - 3)

It is fairly trivial, as this argument shows, that G and <>G entail each other.  This means, definitionally, that they have identical entailments and therefore identical extensions--literally, identical literal meanings.

And, of course, we can continue:

5.) If a premise in an argument and the argument's conclusion have the same literal meaning, the argument begs the question.
6.) <>G is a premise in the MOA and G is the conclusion of the MOA.
7.) <>G and G have the same literal meaning. (From 4)
C.) Therefore, the MOA begs the question.
P((A => B), A) = P(A => B) + P(A) - 1

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alex1212

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Re: The Modal Ontological Argument Begs the Question
« Reply #1 on: March 27, 2016, 01:20:37 pm »
Let G be the proposition "a maximally great being exists."

By definition, then, if G exists, G exists necessarily.  Hence:

1.) G iff []G
2.) <>G iff <>[]G (from 1)
3.) <>[] G iff []G (s5)
4.) G iff <>G (from 1 - 3)

It is fairly trivial, as this argument shows, that G and <>G entail each other.  This means, definitionally, that they have identical entailments and therefore identical extensions--literally, identical literal meanings.

And, of course, we can continue:

5.) If a premise in an argument and the argument's conclusion have the same literal meaning, the argument begs the question.
6.) <>G is a premise in the MOA and G is the conclusion of the MOA.
7.) <>G and G have the same literal meaning. (From 4)
C.) Therefore, the MOA begs the question.

No.

1. If it is possible that God exists, then God exists.
2. It is possible that God exists.
3. Therefore, God exists.

2 and 3 are not the same. The evidence for premise 2 can not include the conclusion, 3.  Proposed evidence for premise 2 includes things like modal intuitions, religious experience, and other arguments for God's existence.

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cnearing

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Re: The Modal Ontological Argument Begs the Question
« Reply #2 on: March 27, 2016, 02:26:32 pm »
Given that I have proven your claim trivially false, already, and you responded with nothing more than a flat denial and no response to the actual logic of my proof, you'll forgive me for assuming that you are the troll you certainly appear to be.

If you want to have an actual discussion, feel free to address my *formal logical proof* in some substantive manner.
P((A => B), A) = P(A => B) + P(A) - 1

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Atheist in Louisiana

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Re: The Modal Ontological Argument Begs the Question
« Reply #3 on: March 28, 2016, 12:03:58 am »
To answer your original question, yes the ontological argument begs the question in modal form.  It does it in the others too.
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alex1212

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Re: The Modal Ontological Argument Begs the Question
« Reply #4 on: March 28, 2016, 02:26:33 pm »
Given that I have proven your claim trivially false, already, and you responded with nothing more than a flat denial and no response to the actual logic of my proof, you'll forgive me for assuming that you are the troll you certainly appear to be.

If you want to have an actual discussion, feel free to address my *formal logical proof* in some substantive manner.

I don't see the problem, and I'm not trolling. It seems to me that all you've done is just described the nature of a deductive argument. I don't see, "Possibly P" and "P" as identical. I don't think the argument is a good argument but not because I think it begs the question. I did respond to the OP and you didn't reply to what I said.

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alex1212

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Re: The Modal Ontological Argument Begs the Question
« Reply #5 on: March 28, 2016, 02:33:57 pm »
But for those who think there's a problem, Craig responds by noting the de dicto and de re distinction. (of the thing vs. of the word)

https://www.youtube.com/watch?v=thr4cKyUuO4

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alex1212

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Re: The Modal Ontological Argument Begs the Question
« Reply #6 on: March 28, 2016, 02:39:30 pm »

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cnearing

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Re: The Modal Ontological Argument Begs the Question
« Reply #7 on: March 28, 2016, 02:41:44 pm »
P and possibly P are not the same in all cases, but hey are trivially the same in the case of P = "a maximally great being exists" or "maximal greatness is instantiated."

As I have proven.

Craig's response regarding de dicto and de res does not address this argument at all.

My proof holds in both the de dicto mode and the de res mode.
P((A => B), A) = P(A => B) + P(A) - 1

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cnearing

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Re: The Modal Ontological Argument Begs the Question
« Reply #8 on: March 28, 2016, 02:52:37 pm »
Also, note that *by definition* you cannot actually offer the modal ontological argument in the de res mode.

Specifically, possibility and necessity are, by definition, features of propositions, since possible worlds themselves are explicitly sets of propositions.
P((A => B), A) = P(A => B) + P(A) - 1

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alex1212

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Re: The Modal Ontological Argument Begs the Question
« Reply #9 on: March 28, 2016, 02:58:43 pm »
P and possibly P are not the same in all cases, but hey are trivially the same in the case of P = "a maximally great being exists" or "maximal greatness is instantiated."

As I have proven.

Craig's response regarding de dicto and de res does not address this argument at all.

My proof holds in both the de dicto mode and the de res mode.

What I mean is that Possibly P (the premise) entails P (conclusion). In other words, you've just described the nature of a deductive argument. The support for God possibly existing is not that God exists. If P is possibly necessary, then it's necessarily possible that P.

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cnearing

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Re: The Modal Ontological Argument Begs the Question
« Reply #10 on: March 28, 2016, 03:38:21 pm »
The support for the possibility of Gid existing cannot--by definition--be anything *less* than the existence of God.

As I proved, the existence of God is a *necessary condition* for the possible existence of God.

You literally cannot support a proposition without supporting all of its necessary conditions at least as well.  That's what necessary conditions are.
P((A => B), A) = P(A => B) + P(A) - 1

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alex1212

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Re: The Modal Ontological Argument Begs the Question
« Reply #11 on: March 28, 2016, 04:42:38 pm »
The support for the possibility of Gid existing cannot--by definition--be anything *less* than the existence of God.

As I proved, the existence of God is a *necessary condition* for the possible existence of God.

You literally cannot support a proposition without supporting all of its necessary conditions at least as well.  That's what necessary conditions are.

That's totally backwards. It has to be possible for God to exist in order for God to exist. If it's impossible for God to exist, then God does not exist.

What points do you disagree with in the video?

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alex1212

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Re: The Modal Ontological Argument Begs the Question
« Reply #12 on: March 28, 2016, 04:46:27 pm »
The only thing that I will grant that you have "proved" is that you can describe the nature of deductive arguments. The nature of a deductive argument is that the conclusion is already hidden in the premises waiting to be revealed by the rules of logic.

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ParaclitosLogos

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Re: The Modal Ontological Argument Begs the Question
« Reply #13 on: March 28, 2016, 06:29:02 pm »

1. Clark Kent is with louise at niagara falls

2.  Clark is superman (Clark Kent exists iff Superman exists.Clark is with Louis iff Superman is with Louise)

3. Superman is with louise at niagara falls

To beg the question Louise needs to believe 1 or 2 because she believes 3.

Support for 1. Louis Lane is with Clark at niagara falls on an assignment.

Sport for 2. when Louis went at Niagara Falls with Clark he felt onto fire and did not burn, and his eyeglasses fell(his wonderful disguise), at all, and, after all he looks like superman.

She does not believes 1 because she believes 3, nor believes 2 because she believes 3

Sadly, afterwards Louise got a defeater for 2 since Clark Kent did not give up his facade and tried to save her when she jumped into the falls.


Arguments do not beg the question. People beg the question.







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aleph naught

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Re: The Modal Ontological Argument Begs the Question
« Reply #14 on: March 28, 2016, 06:30:54 pm »
This means, definitionally, that they have identical entailments and therefore identical extensions--literally, identical literal meanings.

That's false. Just because P and Q are logically equivalent, it doesn't follow that they mean the same thing. <>T is only logically equivalent with T on S5, it's not logically equivalent on S4. But obviously it's not a matter of semantics whether or not S5 or S4 are the proper modal logic system to do metaphysics in.