anonymousj

All,

Some of the response to my argument G have been decidely uncivil. Watch out for the moderators!

cheers,

anonymousj

BLoggins02

And a simple second look at the following line:

clearly shows that line three is not in the assumption set. As can be seen by the assumption set, the conclusion rests solely on the first two assumptions, not on the third.

Besides, the argument wasn't sound to begin with, that was the whole point.

anonymousj

CurbyIII,

I offered the argument as a sound argument-- an argument with all true premises and that is valid. I stand by that claim. Nothing that anyone has produced has shown that one or more of the premises is false or that the argument is invalid. My argument is not 'making any assumptions' (whatever this is supposed to mean) about anything, nor am I.

It is true that I have not shown that premise 1 is true. It is also true that I have not shown that the argument is sound. It does not follow, however, that all I have shown you is an example of modus ponens. You are running together 'producing a sound argument' and 'showing that a sound argument is a sound argument'.

So far, there is no contradiction. It is not part of any definition of sound argument that I am aware of in any logic text that, in addition to all true premises and valid, the premises must be proved to be true also. Indeed, if proofs are sound arguments, this condition could not be satisfied. One would have to produce a sound argument, then produce sound arguments with each of the premises of the original argument as conclusions, then produce sound arguments with each of the premises of those premise-demonstrating arguments as conclusions, and so on.

I said To which you responded, (my emphasis) As a comment on my 'preliminary remark 1, this is almost incoherent, but it looks as though once again you are running together 'producing a sound argument' and 'showing that a sound argument is sound'

cheers,

anonymousj

Jesus Tap-Dancin' Christ

Proof that cows fly:
1)If something exists, cows fly
2)Something exists
-----
3)Therefore, cows fly

Proof that black is white:
1)If something exists, then black is white
2)Something exists
------
3)Therefore, black is white

Proof that eating cabbage will make you turn into the Hulk:
1)If something exists, then eating cabbage will make you turn into the Hulk
2)Something exists
------------
3)Therefore, eating cabbage will make you turn into the Hulk

And for shits and giggles: Proof that anonymousj's poof of God is invalid:
1)If something exists, the anonymousj's proof is invalid
2)Something exists
-----
3)Therefore, anonymousj's proof is invalid.

Wafel

Ok, I must admit I'm really new to this structured logic thing, but uh here we go.


Argument G' - God's existance can be doubted

P1 - We know about god through the bible
P2 - If a something(a text) is proven to be at least partially invalid/wrong, it can't be fully trusted
P3 - The bible says god is omnipotent
P4 - The bible says god is all good
P5 - There is harm/evil in the world

C - God is either not all good or omnipotent (either he's unwilling or unable to stop harm/evil), thus the bible is invalid about P3 and/or P4, therefore the bible is at least partially invalid, therefore we can't trust the bible when it says God exists. Thus it is proven Gods existance can be doubted


Argument N - God's existance can never be proven

P1 - Something can only be proven if there is nothing that questions it's validity based on logic
P2 - Conclusion of G' doubts the existance of God based on logic

C1 - God's existance can't be proven if G' (or another [valid] argument questioning G) is not disproved or invalidated
C2 - Argument G (God exists) is invalid until G' is disproved or invalidated and no valid logic argument doubts the conclusion of G.

anonymousj

philechat,

When you say that premise 1 is not an axiom, if you mean that it is not a necessary truth, what point does this make, if it is true? It is not part of the definition of sound argument that the premises must be necessary truths.

With respect to the third sentence 'It already assumed such argument: "Something exists if and only if God exists".', Will you put this in other words, please! I do not understand your point here-- it is not that I disagree; I just don't understand it and, perhaps a simple rephrasing will clear it up for me.

It is quite true that you are not obligated to accept my premise 1. But, that shows nothing about whether or not it is true, as I am sure you will agree. The truth of premise 1 is consistent with your disbelief, your denial, your ridicule (although to look at some of the responses above you wouldn't think this rather trivial point is true.)

cheers,

anonymousj

anonymousj

BLoggins02,

Your argument is, You later say,
(6) is the conclusion of the argument. It is deduced from (4) and (5) as I understand your notation. (5) comes from (1) and (3)[as you have it presented-- is this what you mean]. Hence the conclusion does depend upon premise (3)

What am I missing?

cheers,

anonymousj

BLoggins02

What you're missing is that I'm using reductio ad absurdum in line 5 to discharge assumption 3. The third assumption was made for the purpose of using reductio.

This is a standard approach in sentential logic.

BLoggins02

Let me be more explicit:

Notation: m,n RAA(k)

Rule: Given a sentence at line m and it's denial at line n, conclude a denial of the assumption at line k.

Assumption set: the union of the assumptions at m and the assumptions at n but not the assumption k.

Bill Snedden

anonymousj:

Okay, it is agreed that the form of the argument you have used is valid. As many have demonstrated, there is no reason to accept the conclusion based on the fact that its first premise can be denied without contradiction. As others have also demonstrated, we can all construct arguments of valid form with disputable premises; neither do they provide any sort of "proof". So...

What's your point?

Regards,

Bill Snedden

[ May 01, 2002: Message edited by: Bill Snedden ]</p>