Descartes' second proof of God's existence in the Meditations

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Bones-O
 
Reply Thu 14 May, 2009 06:22 am
I believe both proofs have been discredited, but I'd like to know them before I jump straight to the refutation.

Descartes wrote:

From the fact that I am unable to think of a mountain without a valley, it does not follow that a mountain or a valley exist anywhere, but only that, whether they exist or not, a mountain and a valley are inseparable from one another. But from the fact that I cannot think of God except as existing, it follows that existence is inseparable from God, and for this reason he really exists.


This argument states: 'if mountain (M), then valley (V)' but allows for not-M, while 'if idea (I) then exists (G)' and since I must be true, then G is true. It seems to me to be a circular argument: essentially what Descartes is saying is that: "If I hold the idea that G is true, then G is true" insofar as he asserts that the idea of G is, partly, that G is true. So by that same token, if part of my idea of a mountain is that it exists, then it exists: the idea of something may contain, as well as properties that are true whether or not the thing exists, the truth value itself as to whether the thing exists. This seems to me to destroy Descartes' entire method, since we can say this about anything. I may have an idea of a winged horse, and that idea may contain the positive truth value of its existence, thus a winged horse exists whether or not I find one. Am I in error here?

EDIT: To put it another way, I can say that the idea of God is inseparable from his non-existence, that the idea itself contains the negative truth value of his existece. Thus since the idea is true (insofar as I have it), the existence is false. I'm not claiming this reasoning is correct, merely that it is in line with Descartes'.

Beyond the circularity of the argument, it seems to me that, accepting that the idea of God contains the truth value of his existence, this still isn't proof. If I then G allows for not-G then not-I: that is, one does not have an idea of God. Descartes claims he has an idea of God; one can simply respond that he does not: he is mistaken. His response would be that he cannot be mistaken, since he has a clear and distinct idea of God, and any judgement about a clear and distinct idea must necessarily be without error. So one can respond that he does not have a distinct and clear idea of God: he is mistaken. How would Descartes respond, do you think?
 
Krumple
 
Reply Thu 14 May, 2009 06:45 am
@Bones-O,
This thread closely resembles many other threads so I won't go into the god part and will only comment on the mountain and valley portion.

To me it all comes down to what definition you want to accept and their point of view.

To me a mountain is just land in a high position and a valley is land in a low position. But they are both just land. Can you have a mountain without a valley or a valley without a mountain? I say there are places where this is true. But it really comes down to how strict you want to be with your definitions.

The Grand Canyon to me is a valley without mountains. Ayers Rock in Australia is a mountain without a valley. But once again do you accept those as definitions of valley or mountain?
 
KaseiJin
 
Reply Thu 14 May, 2009 06:59 am
@Bones-O,
Interesting. As far as I can tell (and I'm not so hot in this area, I'll admit) it looks that you are seeing it reasonably (=practical + logical), honestly, and fairly. I wonder about translation (the original would have been French, I'm assuming)? Also, I always kind of thought that a valley would require two mountains, rather than one.

Anyway, just thinking outloud here, one thing that struck me, is that I'm pretty sure all of us humans could very much agree on what a mountain would be, basically--we can see them, climb up on them, have parts of them slide down onto our houses, and we can fall off of them--valley or no valley, plain or no plain. It seems to be putting a lot of spin on it, and being unfair, to connect that with something that we cannot all agree on seeing, feeling, experiencing, and having empirical knowledge of.
 
Bones-O
 
Reply Thu 14 May, 2009 09:03 am
@Krumple,
Krumple wrote:
This thread closely resembles many other threads so I won't go into the god part and will only comment on the mountain and valley portion.

Thanks, but the question is about Descartes' meditations, and is not elsewhere covered in the Descartes forum so far as I can tell. Please stick to discussing Meditation 5 rather than a Descartes-free view which has no place here. I don't mean to be harsh, just as I'm sure you don't mean to be off-topic.


KaseiJin wrote:
Interesting. As far as I can tell (and I'm not so hot in this area, I'll admit) it looks that you are seeing it reasonably (=practical + logical), honestly, and fairly. I wonder about translation (the original would have been French, I'm assuming)? Also, I always kind of thought that a valley would require two mountains, rather than one.

:bigsmile: Yes, I puzzled at that and, like you said, put it down to translation. By 'valley' I assume he means 'flat ground at bottom of mountain'.

KaseiJin wrote:
Anyway, just thinking outloud here, one thing that struck me, is that I'm pretty sure all of us humans could very much agree on what a mountain would be, basically--we can see them, climb up on them, have parts of them slide down onto our houses, and we can fall off of them--valley or no valley, plain or no plain. It seems to be putting a lot of spin on it, and being unfair, to connect that with something that we cannot all agree on seeing, feeling, experiencing, and having empirical knowledge of.

Well, that's one thing. The principle here lies in that if-mountain then-valley does not depend on mountain to be true. So while, yes, we may all have common experience of a mountain, this does not effect the above reasoning, since it is independent of any experience of a mountain. (You might say one must have experienced a mountain to hold this truth, but the point of Descartes' meditations is to distrust the source of such knowledge until its falsehood leads to a contradiction).

My question is more concerning what happens if you put the truth statement in the idea, which is both circular and, it seems to me, universally applicable irrespective of whether the thing exists. And, furthermore, is not proof, especially in Descartes' schema where all knowledge is claimed to be subject to the most rigorous skepticism.
 
kennethamy
 
Reply Thu 14 May, 2009 09:49 am
@Bones-O,
Bones-O! wrote:
I believe both proofs have been discredited, but I'd like to know them before I jump straight to the refutation.



This argument states: 'if mountain (M), then valley (V)' but allows for not-M, while 'if idea (I) then exists (G)' and since I must be true, then G is true. It seems to me to be a circular argument: essentially what Descartes is saying is that: "If I hold the idea that G is true, then G is true" insofar as he asserts that the idea of G is, partly, that G is true. So by that same token, if part of my idea of a mountain is that it exists, then it exists: the idea of something may contain, as well as properties that are true whether or not the thing exists, the truth value itself as to whether the thing exists. This seems to me to destroy Descartes' entire method, since we can say this about anything. I may have an idea of a winged horse, and that idea may contain the positive truth value of its existence, thus a winged horse exists whether or not I find one. Am I in error here?

EDIT: To put it another way, I can say that the idea of God is inseparable from his non-existence, that the idea itself contains the negative truth value of his existece. Thus since the idea is true (insofar as I have it), the existence is false. I'm not claiming this reasoning is correct, merely that it is in line with Descartes'.

Beyond the circularity of the argument, it seems to me that, accepting that the idea of God contains the truth value of his existence, this still isn't proof. If I then G allows for not-G then not-I: that is, one does not have an idea of God. Descartes claims he has an idea of God; one can simply respond that he does not: he is mistaken. His response would be that he cannot be mistaken, since he has a clear and distinct idea of God, and any judgement about a clear and distinct idea must necessarily be without error. So one can respond that he does not have a distinct and clear idea of God: he is mistaken. How would Descartes respond, do you think?



In another analogy, Descartes says that just as it is an essential property of a triangle that it has three angles, so, it is an essential property of God, that God exists. But that is not true of a winged horse. The idea of a winged horse does not contain the the property of existing, analogously to how the idea of a triangle must contain the property of having three angles. But the idea of God must contain the idea of existence. Why? Because the idea of God is the idea of the most perfect Being conceivable, and nothing can be perfect unless it exists. (Non-existence would be an imperfection). Therefore, God exists. And that is how I think (in fact, I am quite sure) Descartes would respond.

Edit: This is Descartes' revival of the famous Ontological Argument originated by St. Anselm in the 13th century. Until Descartes revived it, the ontological argument had been considered refuted by Thomas Aquinas in his Summa Theologica. It is one of the most important cases of how Descartes repudiated the established Thomism of his day, and initiated modern philosophy. And got into trouble for it.
 
xris
 
Reply Thu 14 May, 2009 10:54 am
@kennethamy,
Am i wrong in saying a benevolent god is not possible so god does not exist?a non benevolent god is possible so god does exist.We make an observation of a particular mountain but that does not prove every valley has a mountain.We could prove everything and nothing by observation and assuming something.Its not possible to observe and make a conclusive argument.
 
Krumple
 
Reply Thu 14 May, 2009 11:13 am
@Bones-O,
Quote:
But the idea of God must contain the idea of existence. Why? Because the idea of God is the idea of the most perfect Being conceivable, and nothing can be perfect unless it exists.


Why must something exist for it to be perfect? Sounds like an assumption to me. I can't really prove the existence of my mind, I really don't have any reference point for it. I just assume that it exists because I am in use of it currently. But upon death will my mind go anywhere? It might just turn off like the light switch and not provide any more electrical impulses. So no light is on and no one is home. Can my mind be said to exist? No... And I don't think you can make the argument that something needs to exist if it is considered perfect. It's taking two idealistic words and stringing them together and calling it a fact of reality.

Why couldn't perfection be able to exist and not exist simultaneously? Seems to me to be more suiting for the word perfection. Although not a logical one but fits the word far better than HAS TO EXIST for perfection to be.
 
kennethamy
 
Reply Thu 14 May, 2009 11:47 am
@Krumple,
Krumple wrote:
Why must something exist for it to be perfect? Sounds like an assumption to me. I can't really prove the existence of my mind, I really don't have any reference point for it. I just assume that it exists because I am in use of it currently. But upon death will my mind go anywhere? It might just turn off like the light switch and not provide any more electrical impulses. So no light is on and no one is home. Can my mind be said to exist? No... And I don't think you can make the argument that something needs to exist if it is considered perfect. It's taking two idealistic words and stringing them together and calling it a fact of reality.

Why couldn't perfection be able to exist and not exist simultaneously? Seems to me to be more suiting for the word perfection. Although not a logical one but fits the word far better than HAS TO EXIST for perfection to be.


I never said (nor did Descartes say) that in order to exist, something must be perfect. There are lots of things that exist that are not perfect. Like me, and like you. What Descartes did say was that if a Being is perfect than that Being must exist. (Perfection is not a necessary condition of existence, but a sufficient condition of existence). And he held that because he held that existence was a perfection, or property that only perfect Beings had, and since God was a perfect being (by definition) God had to have the property of existence, and, therefore, God exists. How could something be perfect unless it existed? In fact, how could something have any property unless it exists? Must not X exist for it to have a property?
 
Krumple
 
Reply Thu 14 May, 2009 12:00 pm
@Bones-O,
Quote:
Must not X exist for it to have a property?


It is an illusion of property though. You have to make the assumption that an object is of itself for it to have a property. I've never found such a thing anywhere. They only appear to have properties but it's only because of the reference point I examine it from. That can change in a moments notice so if I look again it's not the same information.

There was a cup sitting here...
There is some shattered remnants of a cup on the floor. huh...
Where did the shattered cup go?

So you could argue the cup existed but if it did, where did it go?
 
xris
 
Reply Thu 14 May, 2009 12:16 pm
@kennethamy,
kennethamy wrote:
I never said (nor did Descartes say) that in order to exist, something must be perfect. There are lots of things that exist that are not perfect. Like me, and like you. What Descartes did say was that if a Being is perfect than that Being must exist. (Perfection is not a necessary condition of existence, but a sufficient condition of existence). And he held that because he held that existence was a perfection, or property that only perfect Beings had, and since God was a perfect being (by definition) God had to have the property of existence, and, therefore, God exists. How could something be perfect unless it existed? In fact, how could something have any property unless it exists? Must not X exist for it to have a property?
But it means assuming god is perfect not observing he is perfect.
 
kennethamy
 
Reply Thu 14 May, 2009 12:20 pm
@xris,
xris wrote:
But it means assuming god is perfect not observing he is perfect.


God is perfect by definition, just as a triangle has three angles, by definition.
 
Krumple
 
Reply Thu 14 May, 2009 01:37 pm
@Bones-O,
Quote:
God is perfect by definition, just as a triangle has three angles, by definition.
Well I beg to differ on this theory. A perfect being would be able to know that an imperfect being would never be able to live up to a perfect beings expectations. Neglecting such a notion would point out a flaw in that perfection.

So there would be absolutely no reason to place any expectations onto such imperfections. It is not only cruel to do it but it points out a flaw in behavior to want to.

EDIT: I felt I needed to explain myself a little more on why I make this claim. So here goes:

It would be like telling your 4 year old child to get their food if they want to eat. So you place their plate onto of a high shelf expecting that they will be able to fulfill such a task. It is cruel to do that... A parent with any sort of sense would know this yet who would do such a thing but a cruel parent?
 
kennethamy
 
Reply Thu 14 May, 2009 01:48 pm
@Krumple,
Krumple wrote:
Well I beg to differ on this theory. A perfect being would be able to know that an imperfect being would never be able to live up to a perfect beings expectations. Neglecting such a notion would point out a flaw in that perfection.

So there would be absolutely no reason to place any expectations onto such imperfections. It is not only cruel to do it but it points out a flaw in behavior to want to.

EDIT: I felt I needed to explain myself a little more on why I make this claim. So here goes:

It would be like telling your 4 year old child to get their food if they want to eat. So you place their plate onto of a high shelf expecting that they will be able to fulfill such a task. It is cruel to do that... A parent with any sort of sense would know this yet who would do such a thing but a cruel parent?



Sorry. I really don't see how this shows that God is not the most perfect Being. What has this to do with what a perfect being knows about an imperfect being? And, I don't understand your analogy either, nor what it has to do with the issue. I think you had better concentrate on Descartes's analogy between the triangle and God. Just as the triangle must have three angles, or it would not be a triangle, so, a perfect Being must exist, else He would not be a perfect Being.
 
Krumple
 
Reply Thu 14 May, 2009 01:53 pm
@Bones-O,
Quote:
I think you had better concentrate on Descartes's analogy between the triangle and God.
See that is my point. You are assuming that god must be perfect. I challenge that definition. Just because a triangle has three angles that makes a triangle but you can't use the same definition process for god and come to the conclusion. It doesn't work that way.

Just like I could take a piece of candy and call it a weapon if I can kill you with it. Sure I probably could find a way to kill you with a piece of candy, but does it now qualify as a weapon? No... if it does then everything qualifies as a weapon.
 
kennethamy
 
Reply Thu 14 May, 2009 04:17 pm
@Krumple,
Krumple wrote:
See that is my point. You are assuming that god must be perfect. I challenge that definition. Just because a triangle has three angles that makes a triangle but you can't use the same definition process for god and come to the conclusion. It doesn't work that way.

Just like I could take a piece of candy and call it a weapon if I can kill you with it. Sure I probably could find a way to kill you with a piece of candy, but does it now qualify as a weapon? No... if it does then everything qualifies as a weapon.


Well, that's the definition Descartes (and Anselm used). We can talk about another definition later, if you like. Let's put it a little differently. If God is the most perfect Being, then he must exist. How is that? That is really the issue. And now, of course, I am not saying that God is the most perfect Being (which is what you objected to). I am saying that if He is the most perfect Being, then He must exist. Do you agree with that?

I think, by the way, that most people would agree that's an appropriate definition of God.
 
Bones-O
 
Reply Thu 14 May, 2009 05:16 pm
@kennethamy,
kennethamy wrote:
In another analogy, Descartes says that just as it is an essential property of a triangle that it has three angles, so, it is an essential property of God, that God exists. But that is not true of a winged horse. The idea of a winged horse does not contain the the property of existing, analogously to how the idea of a triangle must contain the property of having three angles. But the idea of God must contain the idea of existence. Why? Because the idea of God is the idea of the most perfect Being conceivable, and nothing can be perfect unless it exists. (Non-existence would be an imperfection). Therefore, God exists. And that is how I think (in fact, I am quite sure) Descartes would respond.


Cheers, Ken. You've raised some points I was also interested in.

I never believed in the triangle argument. Descartes compares the relation between the essence of God and God's existence with the essence of a triangle and the fact that its angles add up to 180 degrees. This analogy is false so far as I can see, insofar as the angles of a triangle adding up to 180 degrees is part of the essence of a triangle, not a condition of its existence, i.e. a triangle (a figure with three angles adding up to 180 degrees) may be conceived but possibly not experienced.

Your specific analogy here does not seem an analogy to me. I don't see how the idea of a winged horse not containing an existence truth value is analogous to a triangle having three angles, considering that a triangle is quite clearly, by definition and etymological deduction, something that has three angles.

But your argument is very much along the lines of Descartes' first proof of God's existence, and I'm open to discuss this, so long as the focus is not detracted from his second proof. Reason being that there is a relation between the two: Descartes' poses a relation between perfection and existence such that the thing that is most perfect is most real. This in itself is not only arguable, but probably worthy of reject, but assuming this point, God's existence still does not follow, for the reason of my second argument against Descartes' second proof. And, of course, the circular argument remains. I'm quite happy to ignore this point unless discussion depends on its consideration. I'm much more interested in if the circular argument may be true.

Thanks again people!

---------- Post added at 06:29 PM ---------- Previous post was at 06:16 PM ----------

kennethamy wrote:
Sorry. I really don't see how this shows that God is not the most perfect Being. What has this to do with what a perfect being knows about an imperfect being? And, I don't understand your analogy either, nor what it has to do with the issue. I think you had better concentrate on Descartes's analogy between the triangle and God. Just as the triangle must have three angles, or it would not be a triangle, so, a perfect Being must exist, else He would not be a perfect Being.

Hello again Ken. Having read this, I'm wondering if my post was perhaps too subtle, or not forthright enough.

Descartes' argument is that if the idea of God, which contains his existence as true, then it follows that God's existence is true. It does not follow that since a perfect being may exist, there is a perfect being. It merely shows, if you accept such logic, that if a being is perfect, it must exist. One can state as easily as Descartes' states that God is perfect as God is not. And this is even before one approaches the question of whether that which is most perfect is most real, which is almost certainly not true.
 
kennethamy
 
Reply Thu 14 May, 2009 06:25 pm
@Bones-O,
Bones-O! wrote:
Cheers, Ken. You've raised some points I was also interested in.

I never believed in the triangle argument. Descartes compares the relation between the essence of God and God's existence with the essence of a triangle and the fact that its angles add up to 180 degrees. This analogy is false so far as I can see, insofar as the angles of a triangle adding up to 180 degrees is part of the essence of a triangle, not a condition of its existence, i.e. a triangle (a figure with three angles adding up to 180 degrees) may be conceived but possibly not experienced.

Your specific analogy here does not seem an analogy to me. I don't see how the idea of a winged horse not containing an existence truth value is analogous to a triangle having three angles, considering that a triangle is quite clearly, by definition and etymological deduction, something that has three angles.

But your argument is very much along the lines of Descartes' first proof of God's existence, and I'm open to discuss this, so long as the focus is not detracted from his second proof. Reason being that there is a relation between the two: Descartes' poses a relation between perfection and existence such that the thing that is most perfect is most real. This in itself is not only arguable, but probably worthy of reject, but assuming this point, God's existence still does not follow, for the reason of my second argument against Descartes' second proof. And, of course, the circular argument remains. I'm quite happy to ignore this point unless discussion depends on its consideration. I'm much more interested in if the circular argument may be true.

Thanks again people!

---------- Post added at 06:29 PM ---------- Previous post was at 06:16 PM ----------


Hello again Ken. Having read this, I'm wondering if my post was perhaps too subtle, or not forthright enough.

Descartes' argument is that if the idea of God, which contains his existence as true, then it follows that God's existence is true. It does not follow that since a perfect being may exist, there is a perfect being. It merely shows, if you accept such logic, that if a being is perfect, it must exist. One can state as easily as Descartes' states that God is perfect as God is not. And this is even before one approaches the question of whether that which is most perfect is most real, which is almost certainly not true.


This analogy is false so far as I can see, insofar as the angles of a triangle adding up to 180 degrees is part of the essence of a triangle, not a condition of its existence,

But Descartes does not say that triangularity is a condition of the triangle's existence. He simply says that it is a necessary condition of its being a triangle. And. so it is. But Descartes says that just as triangularity is a necessary condition of being a triangle, so, existence is a necessary condition of being a perfect being. So the analogy is triangularity is to being a triangle, as existence is to being a perfect Being. So, you see the difference from what you said the analogy was.

It is not a necessary condition of a winged horse that it exist. It is a necessary condition of a perfect being that it exist. Winged horses need not exist. Perfect beings must exist.

What Descartes argues is that if God is a perfect Being, and if perfection implies existence, then a perfect Being must exist. Now that is a valid argument, which is to say that if the premises are true, then so must be the conclusion. So, the question is, whether both premises are true. Have to any obsection to the first premise that God is a perfect Being (by definition)? Do you have any objection to the second premise, that if a Being is perfect, then if must exist? If not, then you are force to accept the conclusion that God exists. (If you object to the premise that God is a perfect Being, then forget about God, and let's just talk about a perfect Being. It doesn't really matter, since it still follows that a perfect Being exists, whether or not you think that Being is God).
 
KaseiJin
 
Reply Thu 14 May, 2009 07:58 pm
@Bones-O,
Bones-O! wrote:

The principle here lies in that if-mountain then-valley does not depend on mountain to be true. So while, yes, we may all have common experience of a mountain, this does not effect the above reasoning, . . .



Thanks for the feedback and response, Bones-O. This above quoted portion, is, perhaps, one main reason for my seeing spin and unfairness. It looks 'shifty' (if you know what I mean). Otherwise, the mental exercise was fun, back in the good ole days . . . I don't think it's worth thinking about too seriously, but I wish you the best in finding an answer that will settle well in your mind at the moment ! Thanks for the interesting thoughts !

PS... I really wish folks would be more careful about this word 'god' (and thank you Krumple for being so). Descartes was mistaken in a number of ways, and one was most obviously his trying to prop up a Jewish folklore of an entity--that's what we are referring to when we write "God." "God" was most obviously created by imperfect beings, therefore there is no way whatsoever imperfect can be perfect without loosing relative meaning...it seems to me.
 
Theaetetus
 
Reply Thu 14 May, 2009 08:08 pm
@Bones-O,
David Hume brings up a nice counter argument that can be applied to Descartes. We are not justified in attributing more to God than we can gather from the environment. Because the world is imperfect, we cannot assume that God would be perfect. I don't know if that helps at all, but it is a good argument against the idea that God is a perfect being.
 
Krumple
 
Reply Fri 15 May, 2009 12:08 am
@Bones-O,
Quote:
David Hume brings up a nice counter argument that can be applied to Descartes. We are not justified in attributing more to God than we can gather from the environment. Because the world is imperfect, we cannot assume that God would be perfect. I don't know if that helps at all, but it is a good argument against the idea that God is a perfect being.


Thanks Theaetetus, I was actually going to bring that up. However I've been trying to take on a newer perspective because I like human behavior more than logic arguments. So here is another one to go along with gods inconsistency. (in my opinion)

This might be a little off topic but it does have some relevance...

Couldn't god just forgive his creation without needing to do anything in paticular? For example if someone wronged you do you physically need to do anything to make it "official" or can you just simply reflect on the issue in a new way? Do you really need to go up to them and make it a scene? Well no you don't so I ask why would you make it a spectical and how exactly would you go about that scene?

God chose to place himself into the chopping block. Which directly reflects his mindset on how he should go about setting the scene for forgiving humanities sin. This is a sadistic idea in my opinion because couldn't he come up with a far better, more peaceful or appealing scene than a bloody torment of a human being in a cruel mannor? Also shows his lack of imagination (but that is me delving completely off topic)

So how is this relivant? I'm making the case that god does not qualify for the perfect adjective. A being that simply can't just change it's mind but insists on making a scene and a bloody one, shows lack of perfection. (in my opinion)

I could continue this argument with the bible as another example of his lack of perfection. But do you really want me to torture you with any more of my examples?
 
 

 
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