Logical proofs for God

Slow coach wrote:

Oh, well that's definitely it, then!

I, for one, don't believe it's in any way logical to conclude that there isn't a God, and I'm not the only one.

Well, quite. This was what I was driving at - I don't think it's possible to arrive at a definitive logical conclusion on the matter either way, therefore stating that using logic leads to believing in God is a bit daft.

I'd be interested to hear what your chain of logic that leads to God's irrefutable existence is, though.

neuro-praxis wrote:

Fysh said:

Let's then imagine that we are discussing the Unmoved Mover, which is effectively, the creator God. He/She/It did its work and is now sitting back.

Can we logically prove it exists?

I believe so. This is a (summation of) cosmological proof for the existence of God as proposed by Dr. Thomas AF Kelly.

Things whose existences are not necessary are mortal - that is to say, they come into existence and then they pass away. Contingency and temporailty therefore are two sides of the same coin.

If the expression "God exists" is always a contingent (possibly true, but possibly untrue) statement, what can we say?

I'll preface it with a proof that demonstrates that possibility is insufficient for actuality.

p = actual
not p = possible

[example - if a doctor says; "I am a doctor" they are stating actuality. To say "I could become a pilot/chef/helipcopter" is to state what is possible.]

To say that possibility is sufficient for actuality is to say that p = not p. [example, it is for the doctor to say "I am a pilot".]

To say p = not p is a very clear contraditiction, therefore we know that possibility is not sufficient for actuality.

Since we now know with certainty that possibility is insufficient for actuality, then we know that the possibility of a world is not enough for a world to exist. Possibilities of existence do not alter existence. And each event has a cause. Therefore, as we can see that the world is insufficient for its own existence, then there must be something outside of thw world and not identical to itself that caused its existence.

That which grants existence is unique: to provide that which it is to be. What God turns out to be is that which is identical to what it is to be.

Thus the ongoing existence of the world is dependent on the creator of the world for that very existence.

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Refute at will!

Two things :

a)As far as I can tell, I can use the exact same argument, only switching in "god does not exist" or, if you prefer, "god cannot exist", in order to prove things the other way.

b)I've bolded your starting points because I disagree with them. I don't think that one can mathematically separate statements in such a way. If p is what is actual, surely not p would have to be all that is not actual? This will encompass what is possible, surely - but also what is physically impossible and therefore not actual as well?

As an interesting side note, the physicist in me would like to point out that "Since we now know with certainty that possibility is insufficient for actuality, then we know that the possibility of a world is not enough for a world to exist. Possibilities of existence do not alter existence." is technically at odds with what experiments on quantum theory suggest. I mention this more because, having noticed it, I wondered who this A F Kelly chap is, and whether he'd addressed the subject at all.

neuro-praxis wrote:

Disagreeing with syllogistic logic is probably a bad idea. It's like disagreeing that 1+1=2. You can't disagree with it and still be right.

Excuse me? You're telling me that disagreeing with a form of logic which utilises the mathematical form (which, despite the best efforts of the Langlands project, still cannot be proven to be one self-consistent structure with several subforms which can all be intertranslated without any form of corruption or information loss) to try and assume absolutelness whilst still incorporating linguistic elements makes me wrong? Convenient, that. What I disagree with is the notion that we have found a 100% correct way of interpreting human ideas in a form that can accept and not be affected by the myriad inconsistencies and problems inherent in the use of language for thinking. It is a useful tool and chiefly (imo at least) a way of easily finding inconsistencies and/or weak points in arguments.

neuro-praxis wrote:

Your idea that all that is not p encompasses all that is impossible is fine with me. It fits perfectly with what I have said. How does it nullify the equation? We have seen that what is actual is not equal to what is possible and what is impossible. Grand.

Well, it's down to semantics, isn't it. Not p would have to be extensibly defined as all that is possible but is not actual as well as all that is not impossible. Or, you could define it as all that is not actual. Now, having p defined as all that is actual makes defining not p as all that is not actual pretty much obvious. To try and then draw a conclusion from the fallacy of equating p to not p is to ignore that this fallacy is a part of the structure adopted from the mathematical form in the first place. A similar trick can be pulled in mathematics where you prove that a=b for any value of a or b - the problem being that in part of the proof, both have been divided b c which happens to be zero.

You define p as what is actual and not p as what is possible . You then go on to say that because p /= not p, possiblity does not equal actuality. But if not p is everything outside p, it must include anything that is not actual - including that which is impossible. Thus your logic compels you to also accept that impossibility does not equal actuality. Therefore, possibility or lack thereof have no actual influence on actuality. From there, it does not follow that some external entity is necessary for the world to exist.

A third point would be that, even in the case that I somehow accept this logical proof for the existence of a god - how do we then move to prove that the god who is sustaining the universe through a mechanism or mechanisms unknown is the same god described in one or more holy texts currently in vogue?

I'm with Terry Pratchett on this one : "Logic is a wonderful thing, but it doesn't always beat actual thought."

neuro-praxis wrote:

Ah. Now you are moving into relativism. Your basic argument here seems to be that we cannot know anything to be true. If that is your standpoint, then we can't really go anywhere with that, can we? Or is it that you are saying that language is insufficient for expression of truth?

Well, let me ask you then, do you know that the statement "Language is insufficient for expression of truth" is actually true? If you do know it is true, then by what measure do you know it? Surely knowing that it is true nullifies your argument. And if you don't know it to be true - well then, it's moot, isn't it?

I am not stating that language is "insufficient" for the expression of truth, nor that it is sufficient for such a task. I am saying that language is a crude tool initially devised for simple communication and not really entirely adequate for the extended examination of complex metaphysical ideas. It's a tool, and a particularly versatile one at that. However, language has not been specifically developed in such a way as to allow unambiguous and decisive discussion of ideas, therefore it is not always possible to succesfully utilise it for such a purpose. I'll use it where possible, but I accept that it isn't perfect and bear it in mind when looking at arguments such as this.

neuro-praxis wrote:

Now, do you mean formal semantics here, or the colloquial term semantics? If you mean formal, well then, yes of course it is down to semantics - semantics being concerned with the meaning of words! I agree with everything in the above paragraph.

I was using it in the colloquial sense, insofar as my meaning was that this argument doesn't seem to be much better in terms of validity than Descartes' statement that God is perfect, which subsequently "proved" God to exist by stating that something which is perfect must exist. I have already expounded on the area where I thought the definitions were insufficiently specific to be considered valid for a deductive conclusion of any kind to be drawn.

neuro-praxis wrote:

But...I haven't drawn any conclusion, because the equation cannot go on when faced with a contradiction. We are not trying to prove that p is equal to not p here. What is being illustrated simply is that if possibility were sufficient for actuality, then there would be no need for first causes.

I know you aren't trying to prove that p = not p. But you are utilising the fact that p /= not p in your subsequent argument.

Regarding the statement that possibility is not sufficient for actuality; quantum throws a strange light on that one. In the case of two-slit diffraction (a beam of light illuminating a slide with two slits in it, which then creates an interference pattern on a subsequent screen) experiments have shown that even in cases where only one photon is emitted (and therefore, under the classical rules, should have gone through either one slit or the other and not shown any interference pattern) the interference pattern is still seen. Which is a physical example of a case where the possibility of an interference pattern, even without the classical requisites for it, is sufficient to create one. Meaning that the quantum model of the universe isn't necessarily compatible with simple statements on actuality and possibility.

neuro-praxis wrote:

Let's try to re-do the illustration to your satisfaction, using English and not logic.

We've got actuality and we've got all other things - ie everything that not actuality implies.

Now is actuality, or let's call it, REALITY, sufficient so that it is ALSO all other things that are not actuality?

An examination of actuality would show that it does not encompass all possibilities. However, actuality, DOES encompass all impossibilities, thus making impossibility an element of actuality, as opposed to an element of all other things.

I disagree. If something is impossible, how can it be actual? It cannot be materialised or actualised, as to do so would require it to be possible. Actuality is a subset of possibility; but impossibility is a mutually exclusive set to possibility. Therefore, if p is all that is actual or real, not p must not only include all not-actual possibilities, but all impossibilities. Thus, the validity of the statement that p is not equal to not p cannot conclude that possibility is insuficient for actuality, because it does not only involve things that are possible.

neuro-praxis wrote:

And, can you name a causeless event?

It is from the realisation that all actuality must have a cause. The world is not self-actualising. If you can give an example of self actualisation I would be fascinated. If the world realised itself through sheer possibility then we woul dhave no use for logic or physics or metaphysics. If things were existing themselves into relaity out of sheer nothingness, then there would be no order in the chaos. Which there is.

Actually, one of the current theories in physics that has yet to be dismissed is the multiverse theory - everything happens somewhere, determined solely by quantum probability. Another one is the notion of the infinite universe or multiverse - lacking any way of effectively describing how all this could have started (and whether that would require external influence), we instead question if it had to start at all, if it could not be permanent. After all, your statement that there was a starting point which was God who created all matter doesn't really have any more merit than me saying that there wasn't and He/She didn't. Once matter exists, it exists. Causality describes chains of events. Once something exists, it exists. It does not have to continually be recreated by external influence in order to carry on existing.

neuro-praxis wrote:

One does not move to prove that this creator God is sustaining the universe. If nothing is self-actualising, then it is obvious that the turning of the planet, the growth of anything (which we cannot affect) is being influenced by some force that we cannot point to.

But where is the evidence that things do not self-actualise? Outside of the original logical statement from Prof. Kelly, that is. If we are to accept that all things do not self-actualise but are maintained by some form of deity (rather than, say, going with what Occam's razor suggests and saying that a simpler explanation might be that our imperfect language has evidenced one of its many flaws when used in deductive reasoning, and that matter does not have to be "actualised" in order to carry on existing) then I have to point out that at this juncture your "logic" deviates from one of the accepted postulates of science, which is the conservation of energy (and matter, when you take account of special relativity).