adrian52

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Are any metaphysical arguments justifiable in any sense?
« on: December 21, 2014, 01:13:10 pm »
Hello...

I wish there was a 'metaphysics' section, as I would post this there, but this seems somewhat related, and from my limited reading this seems to be the most intelligent part of these forums so I thought I might post it here.

I see Dr. Craig and many others continually post about how God operates outside of the universe, including theories of time and how causality is possible in a timeless sense. These are all fine as speculative theories, but in order to actually demonstrate God's existence, wouldn't one need to prove that any one of these is actually possible, and moreover that it actually exists? And how is it ever possible to prove something that:

(a) Has no empirical support as it is outside of our universe

(b) Has no clear logical support as you don't know whether logic extends outside of our universe. Just because something seems contradictory to us, doesn't mean it is actually contradictory in reality. This necessitates a logical proof that what are brains perceive as impossible definitively describes what is impossible in all of reality outside of our minds (and outside the universe that our minds "know" to their limited extent).

(c) May have no metaphysical support, as you don't know what meta-reality (outside our universe) allows. I guess you could view metaphysical laws as a form of higher-order logic that we are unaware of, or higher order rules.

By the way when I say "outside" I don't mean literally in the spatial sense; as you're probably all familiar with by now there's no clear way to refer to this realm as our language is limited to discussing events in space and time.

Then aren't all metaphysical arguments for God's existence pointless, since there is ultimately nothing that can rigorously support them? I mean you can't even get a good probabilistic estimate out of it. Since almost all of Dr. Craig's proofs (except maybe the historicity of Jesus, and the argument for morality...though the latter has many very serious logical errors in my opinion) centrally rely on some "fact" about the this realm outside of our universe, shouldn't they all be discarded?

I feel like this is a problem with metaphysics in general. So in particular, the Kalam cosmological argument, the teleological argument from design, and the ontological argument would be invalid.

To explain the simplest case, couldn't it be that an omnipotent God is metaphysically impossible? How do you even begin to discuss (probabilistically, at the very least) whether an omnipotent being can exist? If "intuitive grounds" is the best we have, then it seems like you don't really have anything at all as we have no way to judge whether our intuitive understandings extend reliably (or at all) to the realm outside of our universe.

I feel like a Humeian : P
« Last Edit: December 21, 2014, 01:53:20 pm by adrian52 »

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Soyeong

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Re: Are any metaphysical arguments justifiable in any sense?
« Reply #1 on: December 21, 2014, 02:31:31 pm »
Hello and welcome to the forum!

(a) It's possible to tell that something exist by observing its effects without observing the thing itself.  Also, a logical argument that has a valid form and true premises guarantees the truth of the conclusion even if the conclusion has not been empirically verified.

(b)You can't use thought to undermine the rules of thought, such as the law of identity and the law of noncontradiction, without cutting off the branch you're sitting on.  We can allow for the possibility that we are mistaken about whether something is contradictory, but we can't allow for the possibility that reality doesn't behave logically.

(c) Something can't cause itself to exist, but rather it must be caused exist by something outside of itself.  In other words, the cause of physical laws can't be physical laws, but must be something that is outside of them and not subject to following them.  So if the natural world has a cause, whatever the cause is, it must be supernatural. 

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Then aren't all metaphysical arguments for God's existence pointless, since there is ultimately nothing that can rigorously support them? I mean you can't even get a good probabilistic estimate out of it. Since almost all of Dr. Craig's proofs (except maybe the historicity of Jesus, and the argument for morality...though the latter has many very serious logical errors in my opinion) centrally rely on some "fact" about the this realm outside of our universe, shouldn't they all be discarded?

Why are metaphysical arguments not sufficient in themselves?  In sound arguments the truth of the premises guarantees the truth of the conclusion, so there is no need to further support the conclusion.  Metaphysical premises like "out of nothing, nothing comes" have good reasons to accept them and no good reasons to reject them, but if we do run across something that calls one into question, then we can reevaluate arguments based off of it at that time.  Until then, we shouldn't allow the remote possibility that a premise is false prevent us from making conclusions.

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To explain the simplest case, couldn't it be that an omnipotent God is metaphysically impossible? How do you even begin to discuss (probabilistically, at the very least) whether an omnipotent being can exist? If "intuitive grounds" is the best we have, then it seems like you don't really have anything at all as we have no way to judge whether our intuitive understandings extend reliably (or at all) to the realm outside of our universe.

If you want to make the case that God is metaphysically impossible, then be my guest, but I think there are much stronger arguments that God is metaphysically necessary.  The laws of logic are inherent to reality, so I see no good reason why we should expect something outside of the universe to behave any differently.
"Faith is nothing less than the will to keep one's mind fixed precisely on what reason has discovered to it.”

Yeshua answered them, “The reason you go astray is that you are ignorant both of the Tanakh and of the power of God. - Matthews 22:29 (CJB)

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adrian52

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Re: Are any metaphysical arguments justifiable in any sense?
« Reply #2 on: December 22, 2014, 12:23:20 am »
Hello and welcome to the forum!

(a) It's possible to tell that something exist by observing its effects without observing the thing itself.  Also, a logical argument that has a valid form and true premises guarantees the truth of the conclusion even if the conclusion has not been empirically verified.

(b)You can't use thought to undermine the rules of thought, such as the law of identity and the law of noncontradiction, without cutting off the branch you're sitting on.  We can allow for the possibility that we are mistaken about whether something is contradictory, but we can't allow for the possibility that reality doesn't behave logically.

(c) Something can't cause itself to exist, but rather it must be caused exist by something outside of itself.  In other words, the cause of physical laws can't be physical laws, but must be something that is outside of them and not subject to following them.  So if the natural world has a cause, whatever the cause is, it must be supernatural. 


Thank you for the reply and the welcome. In terms of each lettered argument, I would respond in the following way:

(a) I think I agree with you here, but to a limited extent. For instance we do know enough about the universe and its beginnings to begin hypothesizing ideas for how the universe came into existence; one simple example would be string theory and (from what I remember) the collision of something like 11-dimensional branes - higher dimensional planes - that in turn generate universes.  It seems to me that the level of circumstantial evidence you would need to form reliable (implied) conclusions is currently out of our reach when hypothesizing, for instance, that "only God and abstract numbers can exist outside of our universe".

This is something Dr. Craig says regularly in many of his debates, particularly in support of the Kalam argument. He believes that there is no space nor time outside of our universe, and that only two entities could possibly exist there. But he doesn't have any awareness of whether there may be higher dimensions, higher dimensional forms of matter, energy, etc. that could make up entities that up until now we simply can not imagine. So his argument seems highly presumptuous, and from the limited data we have about how our universe is constructed, it is not close to sufficient to justify any sort of exact conclusions about what exists outside of it.

(b) I am not so much trying to undermine the rules of thought as I am trying to understand their limits. Fundamentally, I believe one has to first prove that whatever exists beyond our universe is comprehensible to the human mind, on some logical level. For this I would settle for a partial understanding, that is sufficient to grasp the basics of what is actually occurring. But this of course hasn't been justified, it is simply tacitly assumed in these discussions, that whatever could exist outside of our universe simply *is* conceivable to the human mind, and rationally explainable.

But I don't see how this is justified...isn't it very easily possible that our brains were not designed to understand whatever might exist beyond our universe? What guarantees do we have that any of our theories even make *sense* in such a higher-dimensional realm (or something beyond dimensionality that we can't conceive?). I hope you see where I'm going with this.

I'm not saying logic as a whole may be flawed and that we need to discard or undermine it. I'm saying it may not be sufficient for us to understand whatever realms exist beyond our universe. As a consequence, it may be that what we believe is possible from our (potentially) limited understanding is false when considered from a broader perspective. It may also show that certain things we believe are impossible become possible.

As an example for the latter case, in a 2D plane, to get from point A to point B requires that you walk a certain distance across a flat surface. But in a 3D world, you can curve the plane in on itself, so that you can instantaneously move form point A to point B by simply moving downwards (this is like the depiction of a wormhole in science fiction - where you 'bend' spacetime to travel from one point to another through a higher dimension).

(c) In this case I don't mean that physical laws cause physical laws. I am referring to higher-dimensional laws (which describe what I call meta-reality - the reality outside of our universe that includes our own), that govern physical laws, or specify what form they take, as a subset. We simply have no awareness of what such "metaphysical" or higher dimensional laws might be.

This is similar in a sense to point (b) in that they are 'higher order' laws of logic that would govern all realms of reality. Whether you call them metaphysical laws, or higher order logic, doesn't matter. But the crucial point of (b) was that you need to demonstrate that what we understand as logic is the ultimate form of it, and that it encompasses all realities. Now assuming that one has *not* shown that logic extends consistently and reliably to all of reality outside of our universe, (c) states that we don't actually know whether there are metaphysical laws that actually forbid certain things from happening which metaphysicians like Dr. Craig believe are possible.

Perhaps as a simple example, by Newtonian mechanics it was thought that you could theoretically accelerate to any arbitrarily fast speed. But it took an understanding of special relativity, and then the general framework of general relativity, to understand that we are in fact limited by how fast we can go (the speed of light). Why could there not be similar limitations with respect to higher-order realities?

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As a consequence, since it still seems to me that all three of these are valid, then the metaphysical arguments have no grounds to stand on, because they rely on making some fundamental statement of reality *outside of our universe* that requires an underlying proof that it is (I) possible to make such statements that don't contradict any higher-order laws - i.e. the existence of infinitely powerful beings, for example (II) has a reliable amount of evidence to support the (logically possible) hypothesis.

To whatever extent we can measure our universe, it tells us nothing that is of any use with respect to (II), and the proof for (I) has of course never been attempted. Thus at the most fundamental level, all metaphysical arguments seem groundless, as no conclusion can ever have a solid basis in either logic or in empirical support.

With respect to why metaphysics is not sufficient on its own, you refer to a statement "out of nothing, nothing comes" as an example. But this is not really an absolute statement of reality but a limited, logical understanding based on your experiences in one universe. I don't think you should confuse that with the entire range of realities that could ever exist outside of our universe, which is precisely what metaphysical arguments attempt to address.

The simplest argument I can make is that such a larger reality (beyond our universe) may be incomprehensible to you, and that perhaps what you believe to be impossible is not in fact impossible when considered from this wider perspective. As to why random objects don't just pop into existence, I would say again it may simply be incomprehensible to us.

One would need to prove that logic extends reliably outside of the universe, before any of these grand metaphysical claims can be taken seriously. Of course, within our universe, I would safely agree with you that out of nothing, nothing comes - as otherwise anything and everything would come into being.

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Lastly I am not trying to argue that God is metaphysically impossible. But I do feel that for those who do argue for God's existence, they have to first demonstrate that God is logically possible outside of our universe. But in this respect it is impossible for them to make that argument for reasons (I) and (II) that I outlined above.

I'm writing this at 1:30 AM after watching "Interstellar" (hence the wormhole theory!), so I hope I didn't make too many mistakes!
« Last Edit: December 22, 2014, 12:29:19 am by adrian52 »

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Soyeong

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Re: Are any metaphysical arguments justifiable in any sense?
« Reply #3 on: December 23, 2014, 12:29:07 am »
I think that all of our observational knowledge is descriptive, in that it consists of observed patterns in the way that reality behaves, and not prescriptive, in that reality can't behave in ways other than what we have observed.  It is always possible to not observe something correctly or to misinterpret our observations, so it is always possible for knowledge gained in this way to be wrong.  But should I be bothered by that possibility?  If I let go of a ball and it drops 1,000 times, there is still the possibility that some incomprehensible higher dimensional thing will cause the ball to float the next time I let go of it, but should I let that possibility diminish my confidence that it will drop?  If I turn out to be wrong, then oh well, I've been wrong before and I'll most likely be wrong again.  I will include this new observation and move on with trying to find a new theory that best accounts for all of the evidence. 

(a) Hypothesising 11-dimensional branes doesn't really do anything besides avoid the question of why there is something rather than nothing.  You still need to account for the existence of 11-dimensional branes, so all you've done is suggest the possibility that there might be an intermediate step.  Furthermore, WLC argued that the cause must be personal, so if true, that would remove 11-dimensional branes from being a candidate.  I completely agree he could be wrong about the cause being personal or about only God and abstract numbers can exist outside of our universe, but I've seen no good objections.  If he turns out to be wrong, then oh well, it happens, we'll reevaluate his argument at that point in time, but that shouldn't stop us from drawing conclusions based on the best of our current knowledge.

(b) If something exists that is beyond our capabilities to understand, then we will never know.  We will always move forward with the (possibility wrong) assumption that it is comprehensible, we just haven't figured it out yet.  But again, it's not something that we should be bothered about because there would be absolutely nothing we could do about it.  If we're wrong, then we're wrong, and move on, but the possibility of being wrong shouldn't stop us from drawing conclusions based on the best of our current knowledge.  While it's reasonable to think that there might be aspects of something that is beyond our universe that as aspects that are not comprehensible to us, I see nothing to suggest that there aren't any aspects of it that we can comprehend.  If we turn out to be wrong about wormholes, then we're wrong, but an essential part of learning is not to be afraid of being wrong.

(c) It don't see how it's possible to demonstrate that what we understand as logic is the ultimate form of it short of having omniscience, but I see no need to demonstrate that and no need to be bothered by the possibility that our logic is not in the ultimate form.  It is reasonable to think that our form of logic is sufficient until we run across something that demonstrates that it is not.  And even then, it would be doubtful that we could ever recognize it as such.  So we could be wrong and have no way to tell that we're wrong, but with no reason to think that's the case, there is no reason to think that we're wrong.

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With respect to why metaphysics is not sufficient on its own, you refer to a statement "out of nothing, nothing comes" as an example. But this is not really an absolute statement of reality but a limited, logical understanding based on your experiences in one universe. I don't think you should confuse that with the entire range of realities that could ever exist outside of our universe, which is precisely what metaphysical arguments attempt to address.

Yes, it comes from our limited logical understanding of our experiences with the universe, and it is not prescriptive, but it is entirely reasonable to think that is descriptive of reality until we run across something that force of to reexamine it.

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The simplest argument I can make is that such a larger reality (beyond our universe) may be incomprehensible to you, and that perhaps what you believe to be impossible is not in fact impossible when considered from this wider perspective. As to why random objects don't just pop into existence, I would say again it may simply be incomprehensible to us.

Maybe you're a brain inside a jar and everything you believe to be true about reality is actually a false simulation.  Are you bothered by that possibility?  A reality where objections could pop into existence without cause means that any law can be violated without cause, so such a reality would be fundamentally different from the one in which we find ourselves.  Should we seriously consider the possibility that everything just happens to appear to follow laws by pure chance and that reality could end that charade in the next moment? 

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Lastly I am not trying to argue that God is metaphysically impossible. But I do feel that for those who do argue for God's existence, they have to first demonstrate that God is logically possible outside of our universe. But in this respect it is impossible for them to make that argument for reasons (I) and (II) that I outlined above.

Something can't owe its existence to something that it has caused to exist, so if something created the universe, then it it can't be dependant on the universe for its existence and must exist outside of the universe.  Whatever else that thing is, the ability to cause a universe is an attribute that corresponds to our idea of God.  It is possible I am wrong about that, but I see no good reason to take that possibility under serious consideration.  If I do turn out to be wrong, then I'll correct my mistake and move on.
"Faith is nothing less than the will to keep one's mind fixed precisely on what reason has discovered to it.”

Yeshua answered them, “The reason you go astray is that you are ignorant both of the Tanakh and of the power of God. - Matthews 22:29 (CJB)

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adrian52

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Re: Are any metaphysical arguments justifiable in any sense?
« Reply #4 on: December 23, 2014, 10:50:25 am »
I agree with your definition of observational knowledge, and generally speaking it makes sense not to be concerned with the possibility that the ball may not drop to the ground after a thousand tries. But the main difference between the ball and the metaphysics I am discussing is that the ball is well-known to us both in terms of empirical support and the fact that it inhabits the same universe as we do, and to whatever extent we can take our sense of logic (in this universe) and probably centuries of empirical support seriously, we can safely say that Newton's laws will accurately describe the trajectory of the ball. You're right that in theory there could be some higher dimensional thing that comes in and messes with our fundamental sense of logic, but we at least have some empirical support that this doesn't seem to happen, and our sense of logic is indeed stable.

But I think the general point of (a), (b) and (c) was to show that the theories we might propose to explain how the realm beyond our universe behaves have such little backing in terms of empirical or even logical support that whatever theory you come up with is going to be at best speculative, and that it is generally incorrect to ever claim that some aspect of meta-reality is definitively true or even that it is probably true.

Because there are simply too many unknowns. To have a reliable theory you have to have some reason to believe that your basic sense of logic isn't trumped by a massively superior form of metaphysical law which renders practically all of its conclusions to be wrong or so incomplete that they don't qualify as a meaningful description of anything.

With respect to our universe, from our experiences it appears true to say that logic is sufficiently capable of understanding reality more or less completely, because the theories it generates seem to operate consistently and without any jarring contradictions that make no sense to our minds. So we have a good reason to believe that we can take our sense of logic seriously, and that our minds can understand this world we live in.

Of course our observations may turn out to be completely wrong, but its the best we can do and nihilism helps no one in a practical sense, as you pointed out. But none of this has been proven with respect to the realm outside of our universe, and it isn't really justified to assume this with no argument.

We have no idea whether all of this might turn out to be false with respect to the broader reality outside of our universe - it may be genuinely incomprehensible to us (can you even imagine making sense of a realm devoid of space or time? How much sense would our logic make in such a realm?). To be honest I would think this is a probable outcome; after all you're talking about literally everything in existence outside of our universe. It would be pretty surprising if our mortal minds were capable of understanding it all! This is why it really requires some type of evidence or logical proof, the latter though is probably impossible.

And clearly we do have general empirical support for our theories about our universe as we inhabit the same reality, so we have access to that evidence - but we don't have access to evidence outside of our universe. You were right to point out that we might be able to infer things about the realm that exists outside of our universe, but from what I wrote before what we can imply is quite limited, and certainly not enough (ignoring the certainty of any logical conclusions outside our universe) that we can make any definitive or even probabilistic claims.

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So in general I would say we can't make any metaphysical claims with any real degree of certainty, and this would extend both to claims of God's existence, to how causality operates outside of our universe, to String theory. But the difference between how scientists treat string theory and how Dr. Craig treats God is that in the latter case Dr. Craig wants to claim that his arguments are "probably" true or even that they simply *are* true (i.e. with respect to what exists outside of our universe, Dr. Craig seems to believe that it is definitively true that only abstract numbers or God could exist there).

Meanwhile scientists would at most say that string theory is one possible theory, and that whatever evidence we collect in CERN might be able to validate it a little more than it is, but certainly not to any level of certainty compared to the laws in our universe. In fact there are quite a lot of scientists who would say that string theory isn't real science because there's no real way to prove it, like what I am discussing here.

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Finally you mentioned something about why there is something rather than nothing. I guess my answer is that that is a mystery. Whatever argument Dr. Craig has come up with is going to be speculative and I have no reason to take it seriously because of the aforementioned comments on the application of (a), (b), and (c) to the realm outside of our universe. In general though, I see no reason to believe that the cause has to be conscious rather than non-conscious. One would need a proof to demonstrate that one or the other are impossible, or more likely than the other, but the whole trouble with metaphysics is that I don't think such a claim (either way) can ever be made.

I really believe that at some point we have to accept that we simply don't know the answer, and that while you can hypothesize ideas, they are going to be so far removed from any evidence, or certainty about their logical support, that it is mostly meaningless to discuss such ideas.
« Last Edit: December 23, 2014, 11:03:24 am by adrian52 »

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Soyeong

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Re: Are any metaphysical arguments justifiable in any sense?
« Reply #5 on: December 23, 2014, 01:52:40 pm »
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I agree with your definition of observational knowledge, and generally speaking it makes sense not to be concerned with the possibility that the ball may not drop to the ground after a thousand tries. But the main difference between the ball and the metaphysics I am discussing is that the ball is well-known to us both in terms of empirical support and the fact that it inhabits the same universe as we do, and to whatever extent we can take our sense of logic (in this universe) and probably centuries of empirical support seriously, we can safely say that Newton's laws will accurately describe the trajectory of the ball. You're right that in theory there could be some higher dimensional thing that comes in and messes with our fundamental sense of logic, but we at least have some empirical support that this doesn't seem to happen, and our sense of logic is indeed stable.

Metaphysical principles are based on the same empirical support as the ball.  We observe a pattern and predict that we will continue to see the same pattern in areas that we have not yet observed.  I think is reasonable to predict that gravity will still function as we have observed in areas that we have not yet observed, but it seems, to be consistent, that you would question that if you would also question whether metaphysical principles hold in areas we haven't yet observed. 

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But I think the general point of (a), (b) and (c) was to show that the theories we might propose to explain how the realm beyond our universe behaves have such little backing in terms of empirical or even logical support that whatever theory you come up with is going to be at best speculative, and that it is generally incorrect to ever claim that some aspect of meta-reality is definitively true or even that it is probably true.

What is at best speculative is higher forms of logic.  It's reasonable to make predictions based on what fits with all of the patterns that we have observed, and think that our predictions are true or reality until we run across something that does fit.  At which point we reevaluate what we think is true of reality to include the new evidence.  Until then, we shouldn't be bothered by speculations of higher forms of logic.

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Because there are simply too many unknowns. To have a reliable theory you have to have some reason to believe that your basic sense of logic isn't trumped by a massively superior form of metaphysical law which renders practically all of its conclusions to be wrong or so incomplete that they don't qualify as a meaningful description of anything.

Should scientists stop doing science because there are too many unknowns?  At any time reality could come along and behave in a way that punches a hole in their nice little theory.  No, we do the best we can with the information we've got.  If some massively superior law renders practically all scientific conclusions wrong, then that's ok.  We move on and try to create a better theory that includes all of the new evidence.

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So in general I would say we can't make any metaphysical claims with any real degree of certainty, and this would extend both to claims of God's existence, to how causality operates outside of our universe, to String theory. But the difference between how scientists treat string theory and how Dr. Craig treats God is that in the latter case Dr. Craig wants to claim that his arguments are "probably" true or even that they simply *are* true (i.e. with respect to what exists outside of our universe, Dr. Craig seems to believe that it is definitively true that only abstract numbers or God could exist there).

Meanwhile scientists would at most say that string theory is one possible theory, and that whatever evidence we collect in CERN might be able to validate it a little more than it is, but certainly not to any level of certainty compared to the laws in our universe. In fact there are quite a lot of scientists who would say that string theory isn't real science because there's no real way to prove it, like what I am discussing here.

Metaphysical claims have at least as much certainty as scientific claims, especially considering that science itself is based on metaphysical claims.  Every last scientific claim is about things that we think are probably true and when we have enough evidence, we think it is true.  But no matter how certain we are that an observations indicates that something is true, it's still possible to be wrong. 

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Finally you mentioned something about why there is something rather than nothing. I guess my answer is that that is a mystery. Whatever argument Dr. Craig has come up with is going to be speculative and I have no reason to take it seriously because of the aforementioned comments on the application of (a), (b), and (c) to the realm outside of our universe. In general though, I see no reason to believe that the cause has to be conscious rather than non-conscious. One would need a proof to demonstrate that one or the other are impossible, or more likely than the other, but the whole trouble with metaphysics is that I don't think such a claim (either way) can ever be made.

If the best of what we know about reality supports WLC's claims, then, even though the possibility exists that the there is something unknown that would show that they are false, we should believe that they are true until that happens.  You have given no good reason to take your speculations seriously.  You're free to interact with WLC's arguments for its consciousness.

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I really believe that at some point we have to accept that we simply don't know the answer, and that while you can hypothesize ideas, they are going to be so far removed from any evidence, or certainty about their logical support, that it is mostly meaningless to discuss such ideas.

And if everyone had had that attitude, then we'd never have left Stone Age.
"Faith is nothing less than the will to keep one's mind fixed precisely on what reason has discovered to it.”

Yeshua answered them, “The reason you go astray is that you are ignorant both of the Tanakh and of the power of God. - Matthews 22:29 (CJB)

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adrian52

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Re: Are any metaphysical arguments justifiable in any sense?
« Reply #6 on: December 24, 2014, 01:17:18 pm »
I think you've touched on the one point that is probably the only really controversial aspect of using evidence, and that is that we do expect that what we have observed in the past will continue on into the future. This was actually a problem Hume struggled with and Kant devoted an entire text towards answering. But at the end of the day, I think the conclusions were that not all of our knowledge can stem directly from evidence, and that we do have some 'a priori' knowledge or understanding about the world that enables us to make basic connections, such as our ability to perceive space and time and make sense of it, or our inherent expectations that reality is 'stable' in terms of the future being more or less predictable based on past events.

Even if these notions didn't exist, I think the mind would be forced to create them and take them as fact anyway, because there is no actual way for a human mind to make sense of its environment otherwise; it needs some place to start, even if it is an irrational leap to take.

But just because we're forced to make one metaphysical leap as a practical measure, shouldn't give us license to make as many as we wish! Generally speaking those types of leaps are irrational and so we should try to stick with as few assumptions as possible if you want your conclusions to be as error free as possible.

And besides that, we do have at least some evidence that this metaphysical principle (that the future proceeds predictably from the past) was not completely wrong. All we have to do is look at history, and all the experiments that were conducted, and observe that they agreed with all of our scientific experiments and that they continue to today. Of course this doesn't mean that they will indefinitely into the future, but we can at least say that it is a plausible theory which has been proven right up until now (to whatever extent we can trust our minds - another assumption that we unfortunately can't deal with!).

In metaphysics you are specifically making additional claims that aren't based on any evidence, which is natural since it is outside of our universe. So what you're effectively doing in metaphysics is compounding the problem multiple times, by making additional claims about meta-reality that aren't justified by anything, except in a very weak sense by our intuition (which in and of itself is not a very strong piece of evidence as our intuition is wrong on a regular basis - just ask any working scientist!). Imagine if we had to, for example, make a claim that natural laws are stable in this universe, and then go on to claim that they are stable in the dimension above our universe, and then in every dimension above that. How seriously could you take the conclusion if it is forced to make so many unsupported claims? I would argue not very seriously.

And so, with the existence of God, or any metaphysical idea, you are basically speculating multiple times over, and very loosely trying to tie this back to our local universe partially through these metaphysical assumptions. So for example, Dr. Craig is claiming that causality extends to this realm predictably, that a God can exist which affects realities from a higher dimension (outside of the spacetime of our universe), or that it is "infinitely" powerful (is this even logically possible?), or that it is an unembodied mind (another metaphysical concept, because we have no empirical backing for such an idea on Earth), etc.

Note that none of these ideas follows from any evidence, and none of them follow logically from any idea that we currently have - so they are necessarily the same types of irrational leaps as the ones we are forced to make on Earth in order to understand the world around us. And crucially, none of these types of metaphysical assumptions need to be made for scientists and other thinkers who come up with hypotheses about our local reality that we inhabit - at least, no more than is necessary. It is in this sense that I feel there are simply too many unanswered questions with respect to any metaphysical concept (like God) that would allow it to be considered meaningfully as a theory; all of these unstated but implied rules that you believe exist in a higher-order reality aren't being justified.

So this is why I bring in the questions of higher order logic, or higher order laws. Because it could be that all of these speculations are actually wrong, and that they disagree with meta-reality as it truly is - which is why I feel the point needs to be brought up - not necessarily as something in the background that we should constantly feel paranoid about being constantly wrong, but more as a reminder that when you are talking about metaphysics, your ideas are necessarily going to be claims about meta-reality, which specifically require you to provide a type of justification that is not necessary in our local scientific investigations in the part of the universe we inhabit.

Occasionally scientists must practice metaphysics to come up with a groundbreaking theory (i.e. the theory of general relativity); but at the end of the day, the theory has no value unless its actually supported by the evidence. And that is the crucial difference; no such evidence exists for metaphysics, and logic in and of itself doesn't imply the reality of anything (i.e. just consider the Banach-Tarski paradox - from wikipedia: "Given a solid ball in 3‑dimensional space, there exists a decomposition of the ball into a finite number of disjoint subsets, which can then be put back together in a different way to yield two identical copies of the original ball. ")

edit: Oh and by the way I would actually say that we can't be certain that gravity holds outside of the observable universe, but that it is a safe assumption to make if you want to use it to generate new theories. But at the end of the day, the theories need to have some evidence behind them to take them seriously. Then, combined with the few basic metaphysical axioms we follow to make sense of reality, we can safely understand new things.

Also sorry for the late response, its the holidays so I'm doing a bit or preparing and stuff!
« Last Edit: December 24, 2014, 01:51:03 pm by adrian52 »