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  1. #1
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    God, Logic and Knowledge

    If a Creator God DOES exist, then any argument, however logical, based on the false premise of Godís non-existence is necessarily false. And all knowledge based on the false premise of Godís non-existence is also false.

    Likewise, if a Creator God DOES NOT exist, then any argument, however logical, based on the false premise of Godís existence is necessarily false. And all knowledge based on the false premise of Godís existence is also false.

    Are these statements true or false?




    Edit: Note to mod.

    I am wondering whether this thread would have been better placed in Hypothetical than in Free Thought. If so, please move and apologies for any inconvenience.
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  2. #2
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    Re: God, Logic and Knowledge

    Quote Originally Posted by disinterested View Post
    Edit: Note to mod.

    I am wondering whether this thread would have been better placed in Hypothetical than in Free Thought. If so, please move and apologies for any inconvenience.
    Neither; the thread sounds like it would be more appropriate in Religion or Philosophical Debates. I'll go with the latter.
    Trendem

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    Re: God, Logic and Knowledge

    Quote Originally Posted by disinterested View Post
    If a Creator God DOES exist, then any argument, however logical, based on the false premise of Godís non-existence is necessarily false. And all knowledge based on the false premise of Godís non-existence is also false.

    Likewise, if a Creator God DOES NOT exist, then any argument, however logical, based on the false premise of Godís existence is necessarily false. And all knowledge based on the false premise of Godís existence is also false.

    Are these statements true or false?
    It appears to me like you're asking about the Priciple of Contradiction, where two conflicting statements cannot both at the same time be true.

    If "X" is true, then "Non-X" is false. "X" could have been "Non-X" at some point in its existence, but if "X" is true right now, then "Non-X" is false right now.

    For example: I am an adult "A". I was once a child "C".

    Right now, I am "A", so I cannot right now be "C". So, as it relates to me, "A" is true and "C" is false.

    EDIT: I would add, however, that knowledge gained from a false premise is not necessarily false. Examples include Issac Newton's theory of motion and Einstein's theory of Relativity, both of which are grounded in the idea of a static universe (which is false).

    EDIT 2 (Rep to disinterested for making me think!): In fact, the search for truth and knowledge is predicated on our capacity for sniffing out false premises, for if everything we know proved to be true, there would be no change in our level of understanding. In science in particular, it is the things they DON'T expect to be true that guides them down the path of understanding. They don't go around confirming what they already know; they chase the anomalies. So, in a sense, everything we know to be "true" these days is based on things we discovered to be "false", which utterly destroys the assertion that any knowledge gained from a false premise is necessarily false.

  4. #4
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    Re: God, Logic and Knowledge

    Quote Originally Posted by disinterested View Post
    Are these statements true or false?
    Neither true of false. This falls under the principle of soundness, see the link below.

    Your OP can be reworded to say: Any logical reasoning with an erroneous premise is unsound. True or false ? In this case, the question would be answerable as true.

    The difficulty in this case, is that the big IF that starts both statements will likely never be resolved or answered with certainty.

    Edited
    Last edited by Vandaler; July 11th, 2009 at 07:17 AM.
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  5. #5
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    Re: God, Logic and Knowledge

    Quote Originally Posted by Vandaler View Post
    Neither true of false. This falls under the principle of soundness, see the link below.

    Your OP can be reworded to say: Any logical reasoning with an erroneous premise is unsound. True or false ? In this case, the question would be answerable as true.

    The difficulty in this case, is that the big IF that starts both statements will likely never be resolved or answered with certainty.

    Edited
    Not quite the case.

    I'll copy and paste from an older post: http://www.onlinedebate.net/forums/s...3&postcount=25
    You got some terms mixed around.

    Valid = of proper form
    True = what is said of the subjects and objects is true.
    Sound = both valid and true.

    Here is an example of a valid, untrue argument (unsound):

    1. All cats are mammals.
    2. All mammals live in California.
    3. Therefore, all cats live in California.

    It follows proper form, but premise #2 is untrue. Mammals also live elsewhere than CA. The conclusion however follows the other 2 premises. The argument is valid, but untrue (unsound).

    Here is an example of an invalid, true argument (unsound):

    1. All cats are mammals.
    2. The natural habitat of a dolphin is the ocean.
    3. Therefore, dolphins are mammals.

    All premises are true, even the conclusion. But it does not follow proper form. And the conclusion cannot validly come from the previous premises. It is true, but invalid (unsound).

    The following is a valid, true argument (sound):

    1. All cats are mammals.
    2. All mammals are warm-blooded.
    3. All cats are warm-blooded.

    It is both true and valid, which makes it sound.
    A deductive argument is sound if and only if it is both valid, and all of its premises are actually true.

    The link you provided explains the same thing.

    The answer to both of his questions, is "true". As long as the "then" correctly follows the "or" operator (in both form and truth value), the hypothetical statement is true.
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  6. #6
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    Re: God, Logic and Knowledge

    Quote Originally Posted by Apokalupsis View Post
    Not quite the case.

    I'll copy and paste from an older post: http://www.onlinedebate.net/forums/s...3&postcount=25
    You got some terms mixed around.

    Valid = of proper form
    True = what is said of the subjects and objects is true.
    Sound = both valid and true.

    Here is an example of a valid, untrue argument (unsound):

    1. All cats are mammals.
    2. All mammals live in California.
    3. Therefore, all cats live in California.

    It follows proper form, but premise #2 is untrue. Mammals also live elsewhere than CA. The conclusion however follows the other 2 premises. The argument is valid, but untrue (unsound).

    Here is an example of an invalid, true argument (unsound):

    1. All cats are mammals.
    2. The natural habitat of a dolphin is the ocean.
    3. Therefore, dolphins are mammals.

    All premises are true, even the conclusion. But it does not follow proper form. And the conclusion cannot validly come from the previous premises. It is true, but invalid (unsound).

    The following is a valid, true argument (sound):

    1. All cats are mammals.
    2. All mammals are warm-blooded.
    3. All cats are warm-blooded.

    It is both true and valid, which makes it sound.
    A deductive argument is sound if and only if it is both valid, and all of its premises are actually true.

    The link you provided explains the same thing.

    The answer to both of his questions, is "true". As long as the "then" correctly follows the "or" operator (in both form and truth value), the hypothetical statement is true.
    I side with Vandaler (and Dio) on this one. A conclusion derived from false premises, while unsound, could still be true. For example:
    1) The existence of God is a necessary condition for objective morality.
    2) God does not exist.
    3) Therefore, there is no objective morality.
    Now, assuming that God does exist (thus negativing premise 2), does that automatically mean that there is an objective morality? No - the God which exists might be an amoral God that does not decide on moral issues. After all, premise 1) merely states that God is a necessary condition, not a sufficient condition. Thus, the conclusion is not automatically rendered false.

    In short, both of disinterested's statements are false.
    Trendem

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    Re: God, Logic and Knowledge

    Quote Originally Posted by Trendem View Post
    I side with Vandaler (and Dio) on this one. A conclusion derived from false premises, while unsound, could still be true. For example:
    1) The existence of God is a necessary condition for objective morality.
    2) God does not exist.
    3) Therefore, there is no objective morality.
    Now, assuming that God does exist (thus negativing premise 2), does that automatically mean that there is an objective morality? No - the God which exists might be an amoral God that does not decide on moral issues. After all, premise 1) merely states that God is a necessary condition, not a sufficient condition. Thus, the conclusion is not automatically rendered false.

    In short, both of disinterested's statements are false.
    But is a semblance of truth derived from false premises true? Or is it mere coincidence?
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  8. #8
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    Re: God, Logic and Knowledge

    Quote Originally Posted by Trendem View Post
    I side with Vandaler (and Dio) on this one. A conclusion derived from false premises, while unsound, could still be true. For example:
    1) The existence of God is a necessary condition for objective morality.
    2) God does not exist.
    3) Therefore, there is no objective morality.
    Now, assuming that God does exist (thus negativing premise 2), does that automatically mean that there is an objective morality? No - the God which exists might be an amoral God that does not decide on moral issues. After all, premise 1) merely states that God is a necessary condition, not a sufficient condition. Thus, the conclusion is not automatically rendered false.

    In short, both of disinterested's statements are false.
    I see now. I read the statements too quickly. Essentially, what I copied and pasted is what you said re:

    Here is an example of a valid, untrue argument (unsound):

    1. All cats are mammals.
    2. All mammals live in California.
    3. Therefore, all cats live in California.

    It follows proper form, but premise #2 is untrue. Mammals also live elsewhere than CA. The conclusion however follows the other 2 premises. The argument is valid, but untrue (unsound).

    "untrue" being "false" of course.

    However...you do not agree with Van's first answer (early statement...nor does he, with you in that...

    Vand: Neither true of false. This falls under the principle of soundness,
    Trend: In short, both of disinterested's statements are false.
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  9. #9
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    Re: God, Logic and Knowledge

    Quote Originally Posted by Apokalupsis View Post
    Not quite the case.
    But close enough.

    The only real statement in the OP is what happens when a premise is faulty, the answer: The argument is unsound.

    Since no mention is made about the quality and structure of the actual argument, I simply gave the benefit of the doubt that the argument is valid.I did not err in speaking of unsound being the concern he raises, but I may have overextended in saying that "this falls under the principle of soundness" I grant you that.

    Furthermore...

    Quote Originally Posted by Apokalupsis View Post
    1. All cats are mammals.
    2. The natural habitat of a dolphin is the ocean.
    3. Therefore, dolphins are mammals.

    All premises are true, even the conclusion. But it does not follow proper form. And the conclusion cannot validly come from the previous premises. It is true, but invalid (unsound)
    ... is not precise.

    All cats are mammal and The natural habitat of a dolphin is the ocean are true premises thus the argument is not unsound... (invalid =/= unsound)

    What you have above is simply a weird categorical syllogism that don't make sense. A whole different ball of wax.
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  10. #10
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    Re: God, Logic and Knowledge

    Quote Originally Posted by disinterested View Post
    But is a semblance of truth derived from false premises true? Or is it mere coincidence?
    A truth can derived by luck, intuition, error, etc...

    A truth can come from an unsound argument as well, yes. It all depends of the particular reasoning applied, and where lies the inconsequential error in the premise. In such cases, it only means that the argument is to complex, and that the faulty premises can be bypassed by simplifying and understanding the argument better.

    Added: It could very well be the case as well that the conclusion (true) does not follow from the premises, thus explaining that both a an invalid argument AND false premise arrives at a good result. Thats called luck.
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    Re: God, Logic and Knowledge

    Quote Originally Posted by Vandaler View Post
    A truth can derived by luck, intuition, error, etc...

    A truth can come from an unsound argument as well, yes. It all depends of the particular reasoning applied, and where lies the inconsequential error in the premise. In such cases, it only means that the argument is to complex, and that the faulty premises can be bypassed by simplifying and understanding the argument better.
    Accidental discovery of truth, then?

    If the premise from which a truth is accidentally discovered is false, then there is no assurance that any further discovery from that premise will be true.

    However, if the premise is true then there is every assurance that all further discoveries will be true.

    True or false?
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    Re: God, Logic and Knowledge

    Quote Originally Posted by disinterested View Post
    Accidental discovery of truth, then?
    Sure, newspapers horoscope do it every day.

    If the premise from which a truth is accidentally discovered is false, then there is no assurance that any further discovery from that premise will be true.
    If that is the case, it means that the argument is broken as well, and there is no reason to beleive that this is sustainable until the error is discovered and new, better logical foundations are built.

    However, if the premise is true then there is every assurance that all further discoveries will be true.

    True or false?
    True, as long that the argument is valid and sound, and so are the further discoveries
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    Re: God, Logic and Knowledge

    Quote Originally Posted by Vandaler View Post
    But close enough.

    The only real statement in the OP is what happens when a premise is faulty, the answer: The argument is unsound.
    Unsound is not as accurate as saying it is "untrue". If the premise is untrue, then the statement/premise is false. Unsound, as has been pointed out by numerous sources, means that the argument is untrue/valid, true/invalid, untrue/invalid.

    When we say that the argument is untrue, it is much more specific.

    Furthermore...

    ... is not precise.

    All cats are mammal and The natural habitat of a dolphin is the ocean are true premises thus the argument is not unsound... (invalid =/= unsound)
    Again, you seem to misunderstand what it means to be sound. Your link, my link, my example, all clearly show what this term means. IF an argument is invalid, it is also unsound. IF an argument is untrue, it is also unsound.

    There are three characteristics that identify a "successful" argument.

    Truthfulness (true/false) - the propositions accurately reflecting actual state of affairs

    Validity (valid/invalid) - the form of the argument, laws of logic being correctly applied.

    Soundness (sound/unsound) - It is "sound" when the argument is both true and valid. It is "unsound" when one or both, is not the case.

    To be clear...

    invalid = unsound
    untrue = unsound
    true & valid = sound

    What you have above is simply a weird categorical syllogism that don't make sense. A whole different ball of wax.
    Hmmm...perhaps you'd like to send a correction notice to one of the more popular collegiate textbooks on the matter: http://www.amazon.com/Introduction-L...339146&sr=1-17, maybe even send a notice to the authors themselves, Professors Copi and Cohen (actually, Prof. Copi has passed, and Cohen is continuing the editions, so just him should be sufficient). Copi was a professor, modern philosopher and logician. Cohen is Professor of Philosophy at the Residential College of the University of Michigan.

    /ok, sarcasm aside

    If you were to read your own source...and the one I offered though, it may save you some time. Your claims about "soundness", are patently untrue. You misunderstand what the term means Vand.

    From your source:
    3. soundness: a property of both arguments and the statements in them, i.e., the argument is valid and all the statement are true.



    Sound Argument: (1) valid, (2) true premisses (obviously the conclusion is true as well by the definition of validity).


    From my source, The Internet Encyclopedia of Philosophy, which is a large article database written and maintained by Professors and Philosophers worldwide...says...

    A deductive argument is sound if and only if it is both valid, and all of its premises are actually true.
    That is, SOUND = true and valid. If either F or Inv, then UNSOUND.
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  14. #14
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    Re: God, Logic and Knowledge

    Quote Originally Posted by Vandaler View Post
    Neither true of false. This falls under the principle of soundness, see the link below.

    Your OP can be reworded to say: Any logical reasoning with an erroneous premise is unsound. True or false ? In this case, the question would be answerable as true.

    The difficulty in this case, is that the big IF that starts both statements will likely never be resolved or answered with certainty.

    Edited
    Does an apparently unresolvable "if" detract from truth?

    Have we not now moved from truth to perception of truth?

    Does not truth exist whether perceived or not?
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    Re: God, Logic and Knowledge

    Quote Originally Posted by disinterested View Post
    If a Creator God DOES exist, then any argument, however logical, based on the false premise of Godís non-existence is necessarily false. And all knowledge based on the false premise of Godís non-existence is also false.

    Likewise, if a Creator God DOES NOT exist, then any argument, however logical, based on the false premise of Godís existence is necessarily false. And all knowledge based on the false premise of Godís existence is also false.

    Are these statements true or false?
    Quote Originally Posted by Trendem
    side with Vandaler (and Dio) on this one. A conclusion derived from false premises, while unsound, could still be true. For example:

    1) The existence of God is a necessary condition for objective morality.
    2) God does not exist.
    3) Therefore, there is no objective morality.

    Now, assuming that God does exist (thus negativing premise 2), does that automatically mean that there is an objective morality? No - the God which exists might be an amoral God that does not decide on moral issues. After all, premise 1) merely states that God is a necessary condition, not a sufficient condition. Thus, the conclusion is not automatically rendered false.

    In short, both of disinterested's statements are false.
    Someone is going to say this, so it may as well be me. *Sigh*

    If God has been defined as a moral being (eliminating the possibility of the bolded portion of Trendem's argument), then the assumption that God does exist would, indeed, falsify the conclusion that there is no objective reality.

    Similarly, in the argument:

    1. Only God could be omnipotent
    2. God does not exist
    3. Hence, there are no omnipotent beings

    If the reality is that God does exist, and God has been defined as omnipotent, then the conclusion is falsified, in agreement with the OP's proposition. Also, if our first premise remains true, then we arrive at: "There is only one God, and He is omnipotent". Joy. Hallelujah.
    It is less important what you believe, than why you believe it.

  16. #16
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    Re: God, Logic and Knowledge

    Quote Originally Posted by Zorak View Post
    If God has been defined as a moral being (eliminating the possibility of the bolded portion of Trendem's argument), then the assumption that God does exist would, indeed, falsify the conclusion that there is no objective reality.
    Any such argument would be circular, although (to its credit) it would be very skilfully trying to hide that circularity. Here's why.

    The argument could only be sound and true you were to clearly define "moral being" as "objectively moral being". Every human is a moral being because every human has a set of moral beliefs that s/he believes to be true. Hence, defining God as a moral being would only mean that God holds some moral values; it would not lead to a conclusion that those are the only true moral values.

    Of course, one could claim that God's moral values MUST be the only moral values because God is omnipotent and omniscient (would have to be defined as such for argument's sake) and that there's only one God (this would also have to be a premise of the argument). But even that path wouldn't necessitate the existence of obejective morality merely because of the existence of such a God. The omnipotent, omniscient, one and only God who is a moral being could well be a God whose moral standards are what some (or even most) of us would consider evil. This God's morality then wouldn't support a conclusion that an objective morality exists. It would just be a God whose moral standards are different to those of Joe or Mary, well in line with the notion of subjective morality.

    What follows is that the only way that God's existence could prove objective morality is if it was stipulated that God is the one and only true yardstick for morality. This is, in my opinion, way more than simply saying that God is a moral being. It would require the premise that God is "THE moral being" or "a perfectly moral being". But once we stipulate the premise that God is a perfectly moral being, we are in fact assuming that there can exist a "perfect morality" of such a kind that only one morality can be perfect. No being with a morality in any way different to that of this morality could be said to possess perfect morality. And to assume this, is to assume that objective morality exists in the first place!

    Thus, any argument that the existence of God is evidence of objective morality is a circular argument. Its conclusion that there exists objective morality isn't supported by the premise that God exists but rather by a ( somewhat hidden) premise that objective morality exists.

    1. God exists.
    2. God is perfectly moral (ie, objective morality exists)
    3. Therefore objective morality exists

    Premise 2 is flawed in its attempt to lead to conclusion 3 because premise 2 assumes that conclusion in the first place.
    Last edited by Allocutus; July 11th, 2009 at 08:58 PM.
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  17. #17
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    Re: God, Logic and Knowledge

    This is very reminiscent of presuppositional apologetics.

    Quote Originally Posted by disinterested View Post
    If a Creator God DOES exist, then any argument, however logical, based on the false premise of Godís non-existence is necessarily false. And all knowledge based on the false premise of Godís non-existence is also false.

    Likewise, if a Creator God DOES NOT exist, then any argument, however logical, based on the false premise of Godís existence is necessarily false. And all knowledge based on the false premise of Godís existence is also false.

    Are these statements true or false?


    Edit: Note to mod.

    I am wondering whether this thread would have been better placed in Hypothetical than in Free Thought. If so, please move and apologies for any inconvenience.
    I'm so happy. This is the first time I've ever gotten to charge this fallacy in my entire history on ODN.


    You have committed the logical fallacy of modus tollens, also known as affirming the consequent. It's slightly more subtle than a simple modus tollens, but it is logically equivalent.


    Firstly, we need to discuss the nature of valid implication. Let's call some proposition P, and then a second proposition Q. Let's also accept the premise that:

    "If P is true, then Q is true."

    Which is to say, "P implies Q." So, what this relationship tells us is that if P is true, then it must also be true that Q is true. But what happens if Q is true? Does this mean that P is true?

    The logical answer is "No," but let's give a pretty intuitive example for why:

    1. "If I'm in Germany, then I am in Europe."
    2. "I'm in Europe."
    3. "Therefore, I'm in Germany."

    We could be in France, Italy, etc. There are only two possibly valid arguments coming from implication (without some other caveats, but I'll ignore them for simplicity because they don't matter here):

    1. Modus Ponens

    A. "If P is true, then Q is true"
    B. "P is true."
    C. "Therefore, Q is true."

    And the logically equivalent (note, if you can't draw a logical conclusion from one logically equivalent statement, you'll never be able to draw it from another):

    2. Contrapositive to Modus Ponens (this is logically equivalent)
    A. "If P is true, then Q is true."
    B. "Therefore, if Q is false, then P is false."
    C. "Q is false."
    D. "Therefore, P is false."


    You're committing a modus tollens fallacy on the converse modus ponens. Before you ask, no, I don't expect that you recognize this at first, so let's trot this out:


    1. "If God is true, then X is true."
    2. "Therefore, if X is false, then God is false."
    3. "God is false."
    4. "Therefore, X is false."



    One is your opening premise, that there are certain truths that come out of God's existence. 2, you'll have to take my word on this if you don't see why this immediately follows, is true by nature of the fact that 1 is true. 3 is the our pretend-true assertion. However, then, you affirm the consequent by trying to then argue that you can get this conclusion.


    So finally, completely concretely, here's an example of the invalidity of your argument:

    1. "If God is true, then logic is true."
    2. "Therefore, if logic is false, then God is false."
    3. "God is false."
    4. "Therefore, logic is false."

    This is obviously a false statement. The only statements which would be false statements are statements which are true if, and only if, God is true.
    "Those who can make you believe absurdities, can make you commit atrocities." --Voltaire

  18. #18
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    Re: God, Logic and Knowledge

    Quote Originally Posted by GoldPhoenix View Post
    This is very reminiscent of presuppositional apologetics.



    I'm so happy. This is the first time I've ever gotten to charge this fallacy in my entire history on ODN.


    You have committed the logical fallacy of modus tollens, also known as affirming the consequent. It's slightly more subtle than a simple modus tollens, but it is logically equivalent.


    Firstly, we need to discuss the nature of valid implication. Let's call some proposition P, and then a second proposition Q. Let's also accept the premise that:

    "If P is true, then Q is true."

    Which is to say, "P implies Q." So, what this relationship tells us is that if P is true, then it must also be true that Q is true. But what happens if Q is true? Does this mean that P is true?

    The logical answer is "No," but let's give a pretty intuitive example for why:

    1. "If I'm in Germany, then I am in Europe."
    2. "I'm in Europe."
    3. "Therefore, I'm in Germany."

    We could be in France, Italy, etc. There are only two possibly valid arguments coming from implication (without some other caveats, but I'll ignore them for simplicity because they don't matter here):

    1. Modus Ponens

    A. "If P is true, then Q is true"
    B. "P is true."
    C. "Therefore, Q is true."

    And the logically equivalent (note, if you can't draw a logical conclusion from one logically equivalent statement, you'll never be able to draw it from another):

    2. Contrapositive to Modus Ponens (this is logically equivalent)
    A. "If P is true, then Q is true."
    B. "Therefore, if Q is false, then P is false."
    C. "Q is false."
    D. "Therefore, P is false."


    You're committing a modus tollens fallacy on the converse modus ponens. Before you ask, no, I don't expect that you recognize this at first, so let's trot this out:


    1. "If God is true, then X is true."
    2. "Therefore, if X is false, then God is false."
    3. "God is false."
    4. "Therefore, X is false."



    One is your opening premise, that there are certain truths that come out of God's existence. 2, you'll have to take my word on this if you don't see why this immediately follows, is true by nature of the fact that 1 is true. 3 is the our pretend-true assertion. However, then, you affirm the consequent by trying to then argue that you can get this conclusion.


    So finally, completely concretely, here's an example of the invalidity of your argument:

    1. "If God is true, then logic is true."
    2. "Therefore, if logic is false, then God is false."
    3. "God is false."
    4. "Therefore, logic is false."

    This is obviously a false statement. The only statements which would be false statements are statements which are true if, and only if, God is true.
    This might be implied by the condition "any argument, however logical, based on the false premise of God's non-existence..."

    Which is to say, "Those arguments which for their truth rely on the truth of the premise "God does not exist"."

    For such arguments, God's non-existence must be both a necessary and sufficient condition. (This is just restating your conclusion.)
    If I am capable of grasping God objectively, I do not believe, but precisely because I cannot do this I must believe. - Soren Kierkegaard
    **** you, I won't do what you tell me

    HOLY CRAP MY BLOG IS AWESOME

  19. #19
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    Re: God, Logic and Knowledge

    Quote Originally Posted by GoldPhoenix View Post
    This is very reminiscent of presuppositional apologetics.



    I'm so happy. This is the first time I've ever gotten to charge this fallacy in my entire history on ODN.


    You have committed the logical fallacy of modus tollens, also known as affirming the consequent. It's slightly more subtle than a simple modus tollens, but it is logically equivalent.


    Firstly, we need to discuss the nature of valid implication. Let's call some proposition P, and then a second proposition Q. Let's also accept the premise that:

    "If P is true, then Q is true."

    Which is to say, "P implies Q." So, what this relationship tells us is that if P is true, then it must also be true that Q is true. But what happens if Q is true? Does this mean that P is true?

    The logical answer is "No," but let's give a pretty intuitive example for why:

    1. "If I'm in Germany, then I am in Europe."
    2. "I'm in Europe."
    3. "Therefore, I'm in Germany."

    We could be in France, Italy, etc. There are only two possibly valid arguments coming from implication (without some other caveats, but I'll ignore them for simplicity because they don't matter here):

    1. Modus Ponens

    A. "If P is true, then Q is true"
    B. "P is true."
    C. "Therefore, Q is true."

    And the logically equivalent (note, if you can't draw a logical conclusion from one logically equivalent statement, you'll never be able to draw it from another):

    2. Contrapositive to Modus Ponens (this is logically equivalent)
    A. "If P is true, then Q is true."
    B. "Therefore, if Q is false, then P is false."
    C. "Q is false."
    D. "Therefore, P is false."


    You're committing a modus tollens fallacy on the converse modus ponens. Before you ask, no, I don't expect that you recognize this at first, so let's trot this out:


    1. "If God is true, then X is true."
    2. "Therefore, if X is false, then God is false."
    3. "God is false."
    4. "Therefore, X is false."



    One is your opening premise, that there are certain truths that come out of God's existence. 2, you'll have to take my word on this if you don't see why this immediately follows, is true by nature of the fact that 1 is true. 3 is the our pretend-true assertion. However, then, you affirm the consequent by trying to then argue that you can get this conclusion.


    So finally, completely concretely, here's an example of the invalidity of your argument:

    1. "If God is true, then logic is true."
    2. "Therefore, if logic is false, then God is false."
    3. "God is false."
    4. "Therefore, logic is false."

    This is obviously a false statement. The only statements which would be false statements are statements which are true if, and only if, God is true.
    Thank you so much for your very full reponse.

    Needless to say, I'm not fully understanding it - I'm in way over my head, here.

    Could you help me further by answering the following?

    Does anything change if I substitute "Creator God" with "Barak Obama"?

    Thus:

    If Barak Obama exists, then any argument, however logical, based on the false premise of Barak Obama's non-existence is necessarily false. And all knowledge based on the false premise of Barak Obama's non-existence is also false. Etc.

    Also, does it make any difference if I substitute "based on" with "depends on"?

    And one more question:

    Is a First Cause (such as a Creator God) subject to logic?

    My intuitive answer is that He/it is not since logic is an effect of a First Cause, and a cause cannot be subject to an effect.

    Many thanks.
    Love is: the highest good of an other at my expense.

  20. #20
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    Re: God, Logic and Knowledge

    Quote Originally Posted by disinterested View Post
    Is a First Cause (such as a Creator God) subject to logic?

    My intuitive answer is that He/it is not since logic is an effect of a First Cause, and a cause cannot be subject to an effect.
    I think this is very much like the chicken or the egg question. I would say that the only way a "first cause" could be exempt from any of its effects is if we assume that said effects could have been anything but what they were. That is to say, while I agree that every effect must have a cause, all causes produce their own, unique effects.

    For example, if I strike a stationary ball with another ball of equal mass, I would expect the balls to respond in way that is proportional to the overall friction, mass, velocity etc. contained in the whole of the event.

    However, if I strike a stationary ball with another ball of equal mass, I DON'T expect the other ball to disappear, or remain in place, or transform into a cooked turkey, etc. The effects are the inevitable product relative to the set of cause(s).

    If we wish to argue that a first cause would be exempt from something like logic, then we would expect that such a cause would be inherently illogical in and of itself. This is problematic for reasons I described HERE.

    So, in short, I would not expect a first cause to be exempt from its own effects.

 

 
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