Proof by contradiction

[Jedster]

This is a concept borrowed from mathematics.
Simply put you assume the opposite of what you want to prove, then logically show that your assumption was wrong, hence proving your point.

If you are a Theist, you must assume there is no such thing as God, then from that assumption, you arrive at a contradiction, thus proving there is a God(s).

If you are an Atheist, you must assume there is a God, then from that assumption, you arrive at a contradiction, thus proving there is no God.

Rules: Every statement must be logical. No quotations from any outside source(eg scripture , prophets, messengers etc).
You must also define the word 'God' as you use it.

 

[Polymath257]

One of the big problems with proof by contradiction is that any mistake you make leads you to thinking you have a proof.

Because of this, mathematicians tend to prefer direct proofs simply because any mistakes will actually break the proof.

That said, proof by contradiction is a very powerful technique, especially when concepts are defined negatively. For example, to prove the square root of 2 is irrational (i.e, not rational), we first assume it *is* rational and obtain a contradiction.

As for the topic itself, I have no idea how to define the notion of 'God' and all attempts have been incoherent or trivial. For example, if I *define* God to be 'all of existence', then clearly God exists. On the other hand, that definition seems like an abuse of language.

I'd also point out that you would need to also define the word 'exists'. that can be a tricky one as well.

 

[Valjean]

This assumes there are only two possibilities, and that ruling out one necessarily rules in the other. It's a false dilemma.

 

[Heyo]

This assumes there are only two possibilities, and that ruling out one necessarily rules in the other. It's a false dilemma.

Sometimes, even often, there are more than two options but existence is binary, so no false dilemma here.

 

[Polymath257]

This assumes there are only two possibilities, and that ruling out one necessarily rules in the other. It's a false dilemma.

If the term 'God' is well-enough defined, then there are only two possibilities: it either exists or it does not.

Of course, other definitions may give different answers or even be unanswerable (the question may be undecidable).

 

[Heyo]

I'd also point out that you would need to also define the word 'exists'. that can be a tricky one as well.

If anyone wants to skip that step, you can use my attempt at exactly that task:

5 Planes of Existence

 

[Polymath257]

Sometimes, even often, there are more than two options but existence is binary, so no false dilemma here.

One of the alternatives is that there is no proof either way. So, while a proof by contradiction (either way) would be a valid proof, it is possible that no such proof even exists (either way).

For example, under the usual axioms of set theory, it is undecidable whether there is a 'size of infinity' between that of the natural numbers and that of the real numbers. It is known that no proof of either existence or non-existence can be given.

 

[exchemist]

This is a concept borrowed from mathematics.
Simply put you assume the opposite of what you want to prove, then logically show that your assumption was wrong, hence proving your point.

If you are a Theist, you must assume there is no such thing as God, then from that assumption, you arrive at a contradiction, thus proving there is a God(s).

If you are an Atheist, you must assume there is a God, then from that assumption, you arrive at a contradiction, thus proving there is no God.

Rules: Every statement must be logical. No quotations from any outside source(eg scripture , prophets, messengers etc).
You must also define the word 'God' as you use it.

This is a waste of time. The problem of the existence or not of a God is one that has been gone over in philosophy since the year dot with no resolution, largely due to the sorts of problems Polymath describes.

Just look at all this stuff: Existence of God - Wikipedia

Forget it. You are not going to cut through all that with some 4 line argument on a discussion forum.

 

[Heyo]

If you are a Theist, you must assume there is no such thing as God, then from that assumption, you arrive at a contradiction, thus proving there is a God(s).

If you are an Atheist, you must assume there is a God, then from that assumption, you arrive at a contradiction, thus proving there is no God.

If you are an Agnostic, you can simply point at the fact that the nature of god is unknown and the question of existence therefore mute.

 

[QuestioningMind]

This is a concept borrowed from mathematics.
Simply put you assume the opposite of what you want to prove, then logically show that your assumption was wrong, hence proving your point.

If you are a Theist, you must assume there is no such thing as God, then from that assumption, you arrive at a contradiction, thus proving there is a God(s).

If you are an Atheist, you must assume there is a God, then from that assumption, you arrive at a contradiction, thus proving there is no God.

Rules: Every statement must be logical. No quotations from any outside source(eg scripture , prophets, messengers etc).
You must also define the word 'God' as you use it.

As an atheist I lack a belief in any god that's ever been proposed to me, thus I don't have a definition of god that I use. How can I define something that I'm not proposing even exists?

 

[Nakosis]

This is a concept borrowed from mathematics.
Simply put you assume the opposite of what you want to prove, then logically show that your assumption was wrong, hence proving your point.

If you are a Theist, you must assume there is no such thing as God, then from that assumption, you arrive at a contradiction, thus proving there is a God(s).

If you are an Atheist, you must assume there is a God, then from that assumption, you arrive at a contradiction, thus proving there is no God.

Rules: Every statement must be logical. No quotations from any outside source(eg scripture , prophets, messengers etc).
You must also define the word 'God' as you use it.

Ok, assume an all-powerful, all-knowing God.

To be all-knowing would me God would have to know the future.
To be all-powerful God would have to be able to change the future.
If God changed the future that would mean God's prior knowledge would be wrong. So God would not be able to change the future and still be all-knowing.

So God cannot be able to know the future and change the future. An omnipotent and omniscient God cannot exist.

 

[blü 2]

You must also define the word 'God' as you use it.

Hmm. Let me try this out.

DEFINITION of 'God':
in the set A "all purely imaginary beings"
in the subset B of A "all magical imaginary beings"
in the subset C of B "all magical imaginary beings who, some hold, must be manipulated by gifts including obeisances in return for withholding harm or granting wishes or both"
EITHER an element of C,
OR the one element of the subset D of C "the sole magical imaginary being who, some hold, must be manipulated by gifts including obeisances in return for withholding harm or granting wishes or both (often called "God" with a capital G and no article)."

'Magical' means having the power to alter reality independently of the rules of reality.

ARGUMENT: Gods do not exist.
Therefore there are no purely imaginary beings who, some hold, must be manipulated by gifts including obeisances in return for withholding harm or granting wishes or both.
BUT there are numerous examples of purely imaginary beings who, some hold, must be manipulated by gifts including obeisances in return for withholding harm or granting wishes or both.
THEREFORE gods exist.

 

[Jayhawker Soule]

It seems to me that "If God, then ..." is a premise on life support.

 

[Jedster]

One of the big problems with proof by contradiction is that any mistake you make leads you to thinking you have a proof.

Because of this, mathematicians tend to prefer direct proofs simply because any mistakes will actually break the proof.

That said, proof by contradiction is a very powerful technique, especially when concepts are defined negatively. For example, to prove the square root of 2 is irrational (i.e, not rational), we first assume it *is* rational and obtain a contradiction.

As for the topic itself, I have no idea how to define the notion of 'God' and all attempts have been incoherent or trivial. For example, if I *define* God to be 'all of existence', then clearly God exists. On the other hand, that definition seems like an abuse of language.

I'd also point out that you would need to also define the word 'exists'. that can be a tricky one as well.

Well, not an unexpected answer from you.
As I said, I only borrowed the concept to see what answers, in any, were produced.

 

[Jedster]

This assumes there are only two possibilities, and that ruling out one necessarily rules in the other. It's a false dilemma.

That is so.
But you could pretend for the sake of the exercise.

 

[Jedster]

If anyone wants to skip that step, you can use my attempt at exactly that task:

5 Planes of Existence

Thanks for the link.

 

[Jedster]

As an atheist I lack a belief in any god that's ever been proposed to me, thus I don't have a definition of god that I use. How can I define something that I'm not proposing even exists?

Actually, I am in the same boat.
So this thread is not for us to answer.

 

[MNoBody]

 

[Jedster]

Hmm. Let me try this out.

DEFINITION of 'God':
in the set A "all purely imaginary beings"
in the subset B of A "all magical imaginary beings"
in the subset C of B "all magical imaginary beings who, some hold, must be manipulated by gifts including obeisances in return for withholding harm or granting wishes or both"
EITHER an element of C,
OR the one element of the subset D of C "the sole magical imaginary being who, some hold, must be manipulated by gifts including obeisances in return for withholding harm or granting wishes or both (often called "God" with a capital G and no article)."

'Magical' means having the power to alter reality independently of the rules of reality.

ARGUMENT: Gods do not exist.
Therefore there are no purely imaginary beings who, some hold, must be manipulated by gifts including obeisances in return for withholding harm or granting wishes or both.
BUT there are numerous examples of purely imaginary beings who, some hold, must be manipulated by gifts including obeisances in return for withholding harm or granting wishes or both.
THEREFORE gods exist.

Indeed the gods do exist.
Thanks for answering the OP.

 

[Jedster]

It seems to me that "If God, then ..." is a premise on life support.

Noted.