This is taken from this thread (I think it belongs in "Philosophy" rather than in "Physical and Life Sciences"):
http://www.christianforums.com/t7607122-23/#post59079264.
The relevant discussion starts around post #230.
I´d be glad to hear your critical opinions on my attempt at a refutation.
Here´s the argument, as presented by Naraoia (my attempt at a refutation is directed at this very presentation, but I think it is valid against the "rock too heavy" argument in general):
Here´s my response:
http://www.christianforums.com/t7607122-23/#post59079264.
The relevant discussion starts around post #230.
I´d be glad to hear your critical opinions on my attempt at a refutation.
Here´s the argument, as presented by Naraoia (my attempt at a refutation is directed at this very presentation, but I think it is valid against the "rock too heavy" argument in general):
Naraoia said:A rock God can't lift cannot logically exist in the same universe as a god that can do anything. Either God can lift the weight he can't lift (which is a logical contradiction) or he cannot create such a weight (which means he is not omnipotent).
Let's start with A = God is omnipotent, and put the correct letters on this one:
God is omnipotent (A). Therefore, God can create a rock he cannot lift (B). But if there is a rock God cannot lift, then God is not omnipotent. (~A)
Thus, A ==> B and B ==> ~A. Therefore, A ==> ~A.
Oops?
There is nothing "hard" about this. It is the most basic logic. An omnipotent being cannot exist in a logically consistent world.
Here´s my response:
quatona said:When we start our considerations (be it about gods or whatever) we first have to decide whether we want this discussion, the topic and our arguments be constrained to the logically possible, or whether we allow for the illogical.
(Personally I´m all for the first, simply because the latter allows for all sorts of nonsensical assumptions and claims. On top, the fact that we typically argue with means that imply the acceptance of logic as the limiting framework - we use words like "because", "since", "hence", "either - or" etc. - doesn´t leave much doubt that this is a mutually accepted premise).
So this would be my first question to you:
Before we start our considerations, contemplations, arguments - can we agree on the premise that keep it within the limitations of logic?
1.If your answer were "no", nothing could be shown to be a contradiction - because "contradiction" is depending on logic. If we allow for the illogical there aren´t any contradictions (and your attempt to point out a contradiction would be moot): God could lift a rock he can´t lift, God could simultaneously exist and not exist etc.etc.
2. Hence I am assuming your answer is "yes": You agree with the premise that logic is the limiting framework for our consideration. This means that we don´t allow for anything illogical and also don´t expect nor postulate anything illogical.
Consequently, postulating that "omnipotence" means to be able to do the logically impossible is prevented by virtue of our premise.
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Now for God and rocks.
Premises:
Appeal to God´s omnipotence 1: "God can lift any rock, no matter how big or heavy".
Appeal to God´s omnipotence 2: "God can create rocks of any size and weight".
Both these claims are - although exceptional - meaningful and within the limitations of the logically possible.
Now, logic dictates that these two premises don´t allow for a rock that´s
a: created by God that or
b: that God can´t lift.
Conclusion:
Your synthesis - demanding God to be capable of creating a rock God cannot lift (i.e. to do the logically impossible) - violates our most basic premise: to keep our considerations within the logically possible.