I quite agree.
If a greatest possible existence is necessary (assuming it is possible), then, I think, this implies that necessary existence is not possible outside of the greatest possible existence.
“Nothing exists but God” is the same thing as “God is everything which exists” or “Everything which exists is God”. How this conflicts with materialism is beyond me.
Lib, I’m gonna try one more time.
You’re defining God before you’ve found Him. You’re saying God exists before you’ve found Him. You’re no different from a biologist saying that it’s not impossible for his hypothetical animal to exist, therefore said animal DOES exist, and that he doesn’t have to produce a specimen to demonstrate that he’s right. His logical proof ought to be enough, he thinks, and he can’t understand why he needs to go and find a specimen. He doesn’t understand the difference between a hypothesis (which is all he has) and a theory (which his hypothesis would become when and ONLY when he’s secured a specimen that fits his criteria).
So as I’ve stated before, till you have empirical evidence for the existence of God that can withstand close scrutiny, all you have is a lot of pretty words.
Let me ask a few questions of Libertarian, since he started the thread. These are not merely rhetorical questions despite how they’re phrased. (I’m going to abandon the sub-debate about modal logic to address this, that was a sidetrack in the first place, and more important this other seems…)
I hate to sound like an existentialist, but even if the proof is entirely valid and sound, what does that mean to me or my life? If all that has been proven is the proposition G which stand for the proposition that “the greatest possible existence exists necessarily”, what does that do for me?
If the universe if finite, then the greatest possible existence could be expressed merely as the summation of all the lesser existences, in which case we really would be saying nothing more than “the universe exists.” If the universe is infinite, I doubt that we can meaningfully discuss it.
Neither of those possibilities appears to negate materialism in the slightest. Does the greatest possible existence have to be anything other than material? If the universe defines the upper boundary on the magnitude of possible existence, then clearly not. How can any existence be possible that exceeds the scope of the universe? The materialist can easily answer these queries under his way of thinking. In fact, as a bonus to we materialists, the argument if true would appear to show that the universe necessarily exists, so we need no longer worry about it’s origins, why there’s “something rather than nothing.” I could throw away 10 long years of using the anthropic principle and start using this equally mystifying argument that people will also accuse of being circular in reasoning (note I said accuse.)
Does this existence possess any attributes at all, other than simply being the greatest possible existence? If it has other attributes, are they the kind that can described with terms like “greater” and “lesser”? Are you really going to fight tooth and nail over each attribute, turning that attribute into a scalar variable, aligning the scalar with “greater” and “lesser” poles, defining the upper boundary of the scale, and assigning that as an attribute? I really don’t see where this argument is supposed to go from there, what it’s supposed to accomplish, or how it impacts the life of anybody in the slightest. Anyone got an idea about that?
RexDart: Anytime you see a predicate letter, you may substitute any statement you like for it. Check Elliot Mendelson’s Introduction to Mathematical Logic, 4th edition.
I also think you’re playing fast and loose with your quantifiers in your argument. It looks like you’re using existential instantiation on line 9 and trying to use universal generalization on line 13. Would you mind writing out the quantifiers, to see if you’re using them correctly?
Possibly. Just for reference, the universal quantifier is undefined. However, the truth of a universally quantified statement is. It’s probably that sort of difference.
Libertarian’s real problem is that he doesn’t understand the difference between possibility and existence. It’s probably all that thinking about alternate universes that’s warped his mind.
If something exists, it must be possible, but it doesn’t follow that if something is possible it must exist.
Additionally, differences in probability don’t equate to greater existence. Things and events which have a probability of one don’t exist to any greater degree than anything else (even assuming it’s possible for the probability of an event to equal one).
Lib:
You asked me if I had a choice, besides choosing the brutalist, as my role here.
Of course I do, but the brutalist is the best way of exposing the shuck and jive, and that is what your exercise in logic is.
It’s a magic trick with a stacked deck.
I know nothing about modal logic, and I don’t need to. The fix is in before you even start the fancy flourishes.
I find it especially onerous, because logic and rational thinking are difficult enough on their own.
If one is making a rational case one should try to do it in the simplest and most understandable way possible.
Unnecessary complexity is a sin among engineers, rational thinkers, and those who seek clarity and honest exchange.
Your exercise in modal logic is wholly unnecessary to the debate at hand.
“Garbage in, garbage out,” is a saying well known among computer programmers and other logicians.
As I put brutally before and as you completely and totally ignored in your response, your logic is flawed as your definition of God is flawed.
The God of your definition is limited by the possible, and is only qualified by what is best (if I am to understand your explanation of “necessary existance,” which doesn’t sound to me like best possible, but I’ll take your word for it.)
“Best possible” is a new definition of God, and quite at variance to what is commonly meant by the term.
“Best possible” is what car companies say their financing terms are.
I am playing the brutalist to contrast the shuck and jive.
Your flaw is simple, basic, and readily apparent.
“Best possible” does not define God. It is an attribute of God, as it is also an attribute of financing terms at Crazy Jim’s used car lot.
You are simple using an attribute of a thing to define the thing.
It is a basic logical fallacy. The classic example of this fallacy is the square rectangle conundrum.
A rectangle is a four sided figure where the opposite sides are parellel and of equal length, and all intersections are right angles.
A square is a four sided figure where all sides are of equal length and meet at right angles.
A square is a rectangle, by definition.
A rectangle however is not a square.
On the face of it, this would seem a case where a=b, but b does not equal a, which would be logically fallacious.
It is not becase rectangleness is only an attribute of squareness when applied to squares. It does not define the thing.
Similarly you use an attribute of Godhood in lieu of a proper definition. You have not proved God, you have only proved rectangleness. You have proved a part of the thing, but not the thing itself.
Your logic is flawed by definition before it begins. The deck is stacked and all the hocus pocus that occurs after the intitial stacking is simply misdirection and stage effect. It might be flashy and sophisiticated, but in logic that is a drawback not a positive.
That is why I say you have only proved Fred. Fred is my idiot cousin who has seldom done a thing well in his entire life.
However, he is the only cousin Fred of mine in existence, and his Fredness is unique unto him and nobody could do it as well.
This of course makes him the best possible Fred he can be.
But that ain’t saying much.
God deserves a better proof than Fred, and I don’t think God’s requires a stacked deck or unnecessary flourishes.
Yet another problem with is defining a term in terms of itself. “Possible” means exists in some possible world… but how do we know whether a world is possible? By this definition, a possible world is a world which exists in a possible world. But that doesn’t tell us anything.
I apologize for breaking off abruptly yesterday, but our daughter came to visit us!
It is always a treat when we see her. We watched three movies: Sling Blade, Overboard, and The Exorcist. The first two were thoroughly enjoyable. I love the great moral question that Sling Blade leaves with its viewers — can an evil action come out of a good heart? And Overboard is a wonderful light comedy, with Goldie Hawn conducting an acting tour de force, convincingly playing three very different roles: the hated and dreaded rich bitch, the sweet and nurturing poor woman, and the reformed wealthy matron. On the other hand, the producers of the DVD have ruined a classic and important movie, The Exorcist, with gratuitous overuse of subliminal images that are unnecessary and hokey. There is, however, a very cool new scene not to be found in the original that, to avoid spoiling, I’ll just say involves Regan MacNeil coming down the stairs in a most unique and startling way.
With respect to the topic at hand, there is considerable overlap in some of the objections of materialists, so I think I’ll consolidate those and respond to them:
What does “possible” mean?
In modal logic, possible means truth in at least one world. Thus, the statement “parallel lines do not intersect” is possible because it is true in worlds with flat planes. But it is not true in all worlds, say, worlds without flat planes. Lines on spheres and lines on saddles, for example, may be both parallel and intersecting.
What does “necessary” mean?
Necessary means truth in every world. The statement “A is A” is true in every world. Why? Because of what “world” means.
What is a “world”?
A world is a set of statements. Thus, a world consisting of no true statements is not possible. A world consisting of at least one true statement is possible. A world consisting of only true statements is necessary.
Is modal logic some kind of smoke and mirror thing?
I suppose that’s up to each person to decide for himself. Maybe a bit of history can put it in perspective. If nothing else, this should make for an interesting read if you like learning about the history of things.
Curiously, modal logic was the invention of a materialist, C. I. Lewis (not to be confused with atheist turned theist apologist, C. S. Lewis) in the early 20th century. He developed it to advance his Conceptual Pragmatism philosophy, which required dispensing with a seeming paradox in the first order logic truth table. Those of you familiar with elementary logic know that a false proposition implies any proposition (If A is false, and B is true, then A implies B is true.)
Materialists were its greatest champions for decades. Wittgenstein protege, Georg Henrik von Wright, for example, used it to become the founder of deontic logic. Similar branches of logic were spawned throughout the 1900s as philosophical activity, stuck in a rut for almost a century, suddenly began to flourish once again.
Perhaps the most famous and directly influential application of modal logic, however, has been in the field of computer science. As you can see here, modal logics have made it possible to model and address such concepts as “the train might be late” or “Tom thinks he’s smart”.
Specifically, propositional modal logics have found critical applications in artificial intelligence, reasoning systems, database systems, software engineering, and program behavior theories (algorithms, processes, etc). Modal logic dealing with temporal necessity is indispensible in modeling “the specification, derivation, and verification of programs as programs may be viewed as progressing through a sequence of states, a new state after each event in the system.”
Modal logic was moving along quite rapidly throughout the latter part of the 20th century. Materialists were delighted that they had figured out how to model reality. Who needs God now that truth has been determined to be either contingent on possiblity or else born of necessity?
But the shit hit the fan when, in the late 20th century, Charles Hartshorne, one of the most influential philosophers then alive (he died in 2000), suddenly resurrected one of Anselm’s nearly thousand-year-old ontological arguments (his second one) for the existence of God, and framed it as a modal tableau. His original argument was this:
QED
Horrors! What was once summarily dismissed as an argument that was invalid on so many levels (even today, many otherwise intelligent people, ignorant of these advances in modal logic use the old arguments against ontological proofs) was suddenly clearly valid. You will find that each inference in Hartshorne’s proof follows perfectly from the previous inference. Even the staunchest critics, like Stuber and Stoebenau, were forced to acknowledge the argument’s validity, even as they desperately worked to show its unsoundness.
Soon, Plantinga and others began developing new tableaux, some more controversial than others. Eventually, as the new millenium dawned, this became one of the most active and fertile areas of philosophy as big names battle very publicly, no longer over validity, but now over soundness.
On a highly subjective note, I find it amusing and ironic that the very tool that was developed primarily to render God irrelevant is now the tool that holds the most promise of rendering Him as not only relevant but necessary.
What I seem to be seeing is that materialists who understand philosophy (and in particular the branch of philosophy called logic) are finding it more and more difficult to defend their position as the modal argument continues to simplify, but they certainly are not resorting to declaring modal logic to be smoke and mirrors. It’s simply too essential to modern technology and science.
Only people who are quite unfamiliar with the discipline are rejecting modal logic out of hand. And it appears to me that they are doing so, not because they have found some hidden flaw that has escaped the world’s greatest minds for nearly a hundred years, but because they don’t like the implication of the ontological proof. In other words, they seem to be saying, “It was a good thing when it worked for me, but now that it works for you, it is nonsense.” Thus, the question in the title of this thread.
What’s the difference between “valid” and “sound”?
An argument is valid if its propositions follow from one another by strict rules of inference. There is not one philosopher who says that Hartshorne’s proof is invalid. No one can say that because he would lose all credibility. If you will not allow a modus ponens to fall through to the next inference, then you simply dismiss the whole of logic altogether. A materialist who does that has “bought the farm”, so to speak, and now has nothing other than mystical fuzziness with which to model his material world.
An argument is sound if it is both valid and it’s axioms (or base premises) are true. An honest person is forced, when confronted with a sound argument, to accept its conclusion. Rejection of a sound argument is the very hallmark of intellectual dishonesty.
Therefore, many materialists, while unable to attack the argument’s validity, have attacked its soundness. This or that premise that serves as the basis of the argument is not true, they say. In its earliest forms, there were certainly eminently attackable premises, like Becker’s postulate, for example. No one was forced to accept the proposition that modal status, except for actuality, is always necessary.
But now, arguments have been developed that use far less controversial premises and even do away with the excluded middle approach altogether (like the one under discussion here). So it is becoming increasingly difficult to hold a straight face while attacking the soundness of modern arguments.
What is truth?
There are many theories of truth, some of which were discussed in great detail in the other ontology thread. Someone here mentioned one of them (actually a variant). But this argument holds without respect to any particular theory of truth. The interpretation of God’s nature is left wide open by ontology; thus, holders of the Correspondence Theory of Truth may rightfully interpret God from the argument pantheistically.
But what they may not do is make the sweeping assertion that “Modal logic is absolutely worthless, as it represents nothing.” Certainly, that assertion represents desperate ignorance. A computerized society without modal logic is like an industrial society without mechanical theory.
The questions remain unanswered
No one has yet satisfactorily addressed the questions from the Opening Post.
and
The hedging and protests are not, in my opinion, earning you any points. If you attack the argument’s validity you merely look silly. But if you intend to attack the argument’s soundness, you must address its only two axioms and show why they are false. Flail all you like; it won’t matter. Tease and cajole a la Scylla as much as you want; it means nothing. Evade, and you lose. Misdirect, and you raise suspicion. Hedge, and you waste everybody’s time.
Stop being like Creationists attacking evolution, and answer the damn questions. 
Colbri (from the other thread)
Careless, indeed. I quoted what you wrote. Misquoting is a bannable offense, and I resent any implication that I attributed your quote wrongly. Don’t blame me for your squirming.
I react to this the way Popper reacted to Adler.
There’s obviously no point in addressing your concerns, as they might morph again.
A neanderthal question. It is a good thing that you did not make the same requirement of Peano.
Really? Show me.
Lib:
Beats me, and it can’t. But, I don’t reccal implying that either of these things were true.
I note again, that you have completely and totally failed to address my point:
After this third iteration if you fail again to address the issue I will consider it proof you are being dishonestly evasive.
The God you define is not God.
I’ve explained this in greater detail earlier.
On the contrary, it means I’m trying to drive a point home so that even you can’t ignore it.
As for the rest, live by your words.
You’re absolutely right. If you do not believe that modal logic is suited to determining the existence of god, you would certainly never use it to write computer programs! As we all know, if something cannot be successfully applied to every possible situation, it can never be useful in any situation. Excuse me while I throw away my calculator because it failed to write an essay for me.
You also provide us with the equally brilliant knowledge that if something is useful, it is therefore factually true in every way! Science has been going about it all wrong, theories prove themselves by their very usefulness! Finally I have proof that black holes exist. Hey, now I even have proof that there is an invisible dragon with a gravity-magnet that pulls everything towards the earth at 9.8 m/s 2.
You have it exactly backwards. Nobody here is saying modal logic must be wrong because of the implications. In fact the conclusion, that necessary existence exists, is quite boring. If you believe that everything has a cause, then you will find that everything is necessary. Hence, necessary existence exists. If anything, the conclusion on its own supports materialism and denies random forces. I wish you would explain why you think necessary existence has any religious meaning. “Existence exists” just doesn’t have any religious implications to me.
The problem is that, apart from the conclusion, modal logic is not suitable for being applied to things such as the validity of statements like “god exists.” Possible worlds may be useful in computer programming, but they do not represent anything in actual existence. Something either exists or does not exist. There is nothing to which you can point and say it has the property of “possible existence.” Reality is in fact fundamentally different than computer programming. Incredible, I know. You should also note that just because logic is misused does mean the conclusion will be false, and a true conclusion does not mean the logic was sound.
You can misuse as many forms of logic as you want. You can use computer programming techniques and insist they prove things about reality. You can take common words from our language, and insist that they mean something completely different. Then you can tell us that if we don’t use your computer programming techniques to cook our food, write our essays, and choose our religions, then we are forbidden to use them to program computers. Just don’t expect anyone to follow your nonsensical orders.
Scylla, take note.
That’s how one effectively and politely delivers the argument you’re trying to make. In fact, Nightime’s entire post, though forcefully phrased and dismissive of the argument (obviously the same approach you attempted), is almost the ideal of dismissiveness. N questions and rephrases the conclusion of the OP’s modal argument, disputes the applicability of modal logic to theology (along with English composition and the culinary arts), and derides the soundness of the the OP’s assertion of modal logic’s usefulness, rather than attacking the honesty and character of the poster.
Note also that, although N had posted some objections earlier in the thread, there were no disingenuous accusations of evasion or trickery. Instead, N delivered continued disagreement and a rephrased delivery of position in reference to the OP.
[END OF HIJACK]
Libertarian, I’m confused…not by the modal logic (your explanations have been very thorough), but by the results. It the arguments you’ve presented, how is “God” more then a variable? Other then “greatest possible existence”, what is there to define “God?” I have to put Him in quotes because of Scylla’s example of Fred. His cousin Fred is the greatest example of Fred there is. So, “God” is the greatest possible existence of what? People? Dolphins? Any possible creature in the universe? I’m forced to conclude Scylla is right here; you haven’t defined a God at all. The modal arguments are unassailable because they’re circular arguments that don’t really say anything.
[ul]
[li]God is the greatest possible existence.[/li][li]The greatest possible existence has to exist.[/li][li]Therefore, God exists.[/li][/ul]
OK, so please give us a realistic definition for the greatest possible existence. Tell us why the voice from a burning bush telling us how life should be, filling our hearts with joy and love, and forever touching our souls forever is the greatest possible existence and not the second greatest doing a passable imitation. For you see, I accept that our limited existence may be incapable of understanding the greatest possible existence, but it also follows we might well be capable of overestimating the extent of what is “the greatest possible.” For this to be a meaningful argument and not an exercise in semantics we need to know just what you’re arguing for beyond a three word nebulous term.
Respectfully yours,
InkBlot
It’s been a long time since my logic class but I have to agree that this proof comes a far cry from defining any god I’ve heard of. Wheres the control? Where’s the will?
Consider a “keystone” molecule in the centre of the universe. It’s position and spin determines the position and cohesion for the rest of the universe. Is this the “greatest possible existence”? It would certainly contain all possible knowledge. Is this our materialist god then?
It is also open to age old recursion argument against god. If god is necessary right now what conditions created god. Consider an early biology mystery. Many features of a single cell animal are not able to exist without a cell wall. One theory is micro-bubbles in mud acted as the first proto-cell wall for life to begin. Are these micro-bubbles god or is it the conditions that created the bubbles? If the conditions necessary for proper bubble formation change is god dead?
A usual claim of gods is omnipotence. That ability itself negates logic. Consider that if god is all powerful he may change any state, including his own. So we have:
G->~G v G
(can this be expanded to G & ~G v G & G ??)
Therefore if you ever “prove” the existence of an all powerful god you must accept that it might not exist. My goodness, I have a valid proof of agnostism.
There can be none.
It cannot be.
Now what?
I did that in my post where I compared you to a biologist who believes that all he has to do is construct a sound, logical argument that an animal exists in order to demonstrate that it does exist, that it deems it silly and unnecessary to actually go out and find the damn thing.
Stop asking silly, pointless questions.
Libertarian, your argument has two parts. What the modal logic component of your argument actually proves is that if a statement H possesses the following properties:
[list=1][li]If H is true (in this world), then H is necessarily true (true in all possible worlds).[/li][li]H is possibly true (true in at least one possible world).[/list=1]Then H is a true statement.[/li]
The second part of your argument is not based on modal logic. You attempt to convince us that the statement “God exists” possesses these two properties.
If you adopt statement 1 above as the definition of God, then one could reasonably question whether this statement implies a God that resembles any traditional religions conception of the Diety. Many other posters here have addressed this issue.
You ask how the greatest possible existence might not be possible. As an analogy, consider the greatest possible whole number. One might reason that because it is the greatest possible, by definition it must be possible that this number exists. However, there is no greatest whole number because every whole number has a successor which is greater still. The greatest possible whole number cannot exist in any possible world, so is impossible. You can argue, of course, that no similar reasoning applies to existence. However, this shows that simply being the “greatest possible” does not tautologically imply that something is actually possible.
In the past, you have also argued that a skeptic should be obliged to give you the benefit of the doubt by admitting that the existence of God is at least possible. This might be proper in most forms of debate, but I believe it is a practice that should not apply to modal logic. The first definition of possible in the American Heritage dictionary is “Capable of happening, existing, or being true without contradicting proven facts, laws, or circumstances.” To admit that God’s existence is possible in this sense is only to show that one is not close-minded on the subject. All agnostics and many atheists would have no problem with such an admission.
However, the field of modal logic uses a different definition of the word “possible.” To admit that a statement H is possible in the modal-logic sense is to concede something very concrete: that there actually exists a possible world in which H is true. You have stated in the past that you are not prepared to concede that it is possible in the modal-logic sense that God not exist. Given this, I do not see why I must concede that the existence of God is possible. Put simply, I am not prepared to accept your second axiom on faith. If you want me to admit that there exists a possible world in which God exists, you’ll have to prove it.
Other threads have amply demonstrated that it’s pointless to argue with (or more precisely, at) Libertarian.
He’s just a very sophisticated troll. Responding accomplishes nothing: it merely encourages him.
I would recommend ignoring him. Perhaps he will go away.
Libertarian:
Your definition of God is flawed. When you say God = “necessary existence”, the left hand side is a thing, and the right hand side is a property. That is just as silly as defining a watermelon by watermelon = tasty.
When you say “It is possible God exists” you mean (by substitution): “Necessary existence” exists in at least one possible world
If you take the quoted phrase as read, this makes no sense, as properties don’t live in possible worlds. Things do, and we assign them properties.
Perhaps you mean
“A thing that exists in all possible worlds” exists in at least one possible world.
Well then your axiom contains your conclusion:
“A thing that exists in all possible worlds” exists <- CONCLUSION
in at least one possible world. <- added in axiom, REDUNDANTLY
Note that even if we accept the axiom, what is so “great” about a thing that exists in all possible worlds?
I think you call it “God” because “the greatest possible existence”, which you seem to interchange with “necessary existence”, is a highly misleading phrase. It implies a spectrum of existences, where say someone who is just like me but can bench press 10 pounds more than me is at a greater level of existence. But there are no levels of existence like this. Something either exists or it does not within a world, and across possible worlds, it either is necessary or it is not. Thus in terms of existence, given a specific world, something can either
You seem to be saying “God” has property 1. But accepting your axiom, which is directly your conclusion, however you want to obscure it with symbols, all we know is something with property 1 exists. “God” and my dog might both have property 1. So how do you know it is “God” and not my dog, that is the thing whose existence we conclude (and assume, actually).
I think Nightime said all I had to say regarding the validity of modal logic. Well done, sir.
I still haven’t gotten from Libertarian any answers to the other part of my last post, in which I asked “well, what does it mean even if it is true?” I am very, very interested in seeing these questions addressed.
Specifically, two points:
1.) In a finite universe, cannot the greatest possible existence be expressed as a summation of lesser existences? I believe it could, and this would be entirely consistent with materialism. Any finite attribute can be expressed as a sum of other finite attributes. Thus the greatest possible existence would be a material, finite existence consisting of the summation of all other finite existences contained within the universe. For your argument’s conclusion to be incompatible with materialism, it seems you must also demonstrate that the universe is infinite.
2.) What does the conclusion that the proposition “G”, as defined by your proof, is true mean to my own existence? How does it have any impact on me? It seems correct that, as others have pointed out, there really is no relation between your calling this proposition “God” and any god of which we are familiar. This certainly isn’t any sort of “God”, if it can even be called an entity rather than merely a property, about which any of our lives would change in the slightest to learn it existed.
Basically, what I’m saying is this. Define “God” the way you have and then shout from the rooftops “God exists”…and see who really cares. I am baffled, I cannot find any purpose to putting forth this argument. Generally an argument is put forward to convince a person of a conclusion, not just for the fun of it, but to influence that person’s beliefs or behaviours. This argument does neither of those even when successful.
No religious person I know would ever use this argument to convince people of the existence of any god, because your conclusion doesn’t remotely resemble any of their gods. They would still be left at the end of the proof having to admit that their beliefs about the attributes of this entity, in fact their belief that it had any attributes at all other than existence, is based solely on faith. So I must ask again, what’s the point?