Argument from contradiction

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Wootah
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Argument from contradiction

Post #1

Post by Wootah »

https://en.wikipedia.org/wiki/Proof_by_contradiction

https://en.wikipedia.org/wiki/Reductio_ad_absurdum

If you understand these two logical rules you can understand why you don't have to prove something exists to know it exists.

If I can prove a contradiction then the opposite must be true.
Proverbs 18:17 The one who states his case first seems right, until the other comes and examines him.

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Re: Argument from contradiction

Post #2

Post by elphidium55 »

you don't have to prove something exists to know it exists
This is not exactly true as stated; let's see if we can fix it a bit.

Some things can be shown to be true by logical deduction, for example by using "modus ponens" (if A then B; A, therefore B)

(A) If it rains tonight, then
(B) my sidewalk will be wet in the morning;
I observe (A) -- it's raining tonight;
therefore I can infer (B) -- my sidewalk will be wet in the morning.

Some things can be shown to be true by generating a reductio ad absurdom. This is done by showing that the negation of the main premise leads to a adsurd conclusion (if "not-A" then B; but B is absurdly false)

(not-A) if the earth is flat, then
(B) people would be falling off it's edges;
I observe (B), people falling off the edge of the earth is false and absurd,
therefore I can infer (A), the earth is not flat.

So here is what I think is perhaps a better articulation of what you were trying to say:
sometimes, you don't have to have empirical evidence of something to know it exists
What do you think?

FYI: in philosophy, a proof, including a proof from contradiction, is usually restricted to mathamatics.

Also be careful about confusing beliefs with knowledge. To know something is to assert that the proposition in question is a justified/warranted true belief. All knowledge entails belief but not all belief entails knowledge.

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Re: Argument from contradiction

Post #3

Post by Bust Nak »

Wootah wrote: Wed Feb 05, 2020 7:46 pm If you understand these two logical rules you can understand why you don't have to prove something exists to know it exists.
What do you think a proof by contradiction starting with an assumption of non-existence is, if not a proof of existence?

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Re: Argument from contradiction

Post #4

Post by elphidium55 »

With regard to @Wootah's statement that:
If you understand these two logical rules you can understand why you don't have to prove something exists to know it exists.
@Bust Nak wrote:
What do you think a proof by contradiction starting with an assumption of non-existence is, if not a proof of existence?
@Bust Nak I agree with you. A proof by contradiction can prove something exists. But I think @Wootah's statement that "you don't have to prove something exists to know it exists" is a mistake. Proof is required—and the reductio is that proof. I am assuming that this was what @Wootah was trying to communicate.

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Re: Argument from contradiction

Post #5

Post by emilynghiem »

elphidium55 wrote: Tue Jun 02, 2020 4:28 pm With regard to @Wootah's statement that:
If you understand these two logical rules you can understand why you don't have to prove something exists to know it exists.
@Bust Nak wrote:
What do you think a proof by contradiction starting with an assumption of non-existence is, if not a proof of existence?
@Bust Nak I agree with you. A proof by contradiction can prove something exists. But I think @Wootah's statement that "you don't have to prove something exists to know it exists" is a mistake. Proof is required—and the reductio is that proof. I am assuming that this was what @Wootah was trying to communicate.
Dear @Bust Nak @elphidium55 and @Wootah's
(A) First neither the existence nor nonexistence of God
can be scientfically proven or disproven. Because God's nature
is infinite, and human perception and expression is finite, we
can never fully contain or represent God, and this remains faith based, either way.

(B) What we are instead doing when we "prove" something about God to someone
is reaching an AGREED UNDERSTANDING which again is FAITH BASED.
We AGREE we are talking about the same common truth or principle about God or God's laws.

(C) Thus, any "steps of proof" we use are actually RELATIVE to the person/audience we are addressing.

If this person comes from a background on NOT BELIEVING God is universally Good or about to overcome all Evil,
that means that person has COUNTEREXAMPLES or CONTRADICTIONS
that to them means "God does not exist as taught or represented"

the PROOF process is more like a "contrapositive" proof of
ELIMINATING these objections, one by one, or cancelling them
out as neutral (again, because they are faith based, and could go either way)

(D) Finally, what this process ends up looking like IN GENERAL
(again, each "proof" is different for each person who has their own
reasons for assuming or questioning the nature of God is not as taught)

The person throws out objections or "counterexamples"
for the other person to answer, until the person either
accepts that answer eliminates the objection,
or the two people "tie or deadlock" and agree it could be either way,
neither is proven to be the only possibility that necessarily negates the other.

After addressing every objection that comes up
(which can also include purely emotional reasons for bias or rejection,
such as not forgiving family members or other Christians who were abusive),
and either resolving those or forgiving and healing the negative impressions,
EVENTUALLY people run out of objections because human thinking is finite.

In a mathematical or scientific proof, there are an infinite number
of other possibilities. So in theory, a "contrapositive" proof would fail.

But in REAL LIFE, by nature of human beings having FINITE REASONS
and a pattern for their beliefs, perception and process of change,
People run out of objections.

That's why they either reach a state of AGREEMENT
or reach a state of neutral perception of their differences.
As long as they reach a NEUTRAL state of NO LONGER REJECTING,
that is usually sufficient for the person's DEFAULT beliefs to kick in.

So whatever that person believes BY DEFAULT
becomes their proof of how God's nature operates.

This IMITATES the steps of a contrapositive proof
by seemingly "eliminating" or "disproving" counterexamples.

But this is really "cheating" because human nature has limits to it:
(a) first is the limit on objections preventing that person from reconciling
(b) second is whatever the person's "default" beliefs,
that is where their understanding of God lies.
It is purely faith based, and can not REALLY be "proven or disproven"

The process is actually coming to a faith based AGREEMENT.

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Re: Argument from contradiction

Post #6

Post by elphidium55 »

@emilyngheim:
Your argument is a bit hard to follow. Also, you make a couple of moves which are a bit dodgy. However, I think that you are on to something important. Let me sketch out an idea that I find congenial that may have some uprising overlap with your point of view.

Note: this is not my original idea but instead follows from some ideas put forward by the Australian philosopher Graham Oppy.

1: There are, as yet, no successful arguments either for or against the question of the existence of God.

2. Given that this question of the existence of God has been debated inconclusively for over 2500 years, it is very unlikely that there will be a successful argument pro or con about this question in the foreseeable future.

Some definitions:
by God I mean the omnipotent, omniscient, omnibenevolent god as generally described by the monotheistic religions;

by argument I mean arguments that are competent, that is we are putting forward arguments which are the best versions of the themselves;

by successful argument, I mean an argument that is so convincing, that upon being presented with it, an open-minded, rational, and well-informed thinker should be required to change their opinion on this question. In other words, a successful argument should compel an intellectually honest atheist to become a theist or an intellectually honest theist to become an atheist.

Why do we not have any such successful arguments? Consider the following two arguments.

Premise 1: Everything that begins to exist has a cause of it's beginning to exist.
Premise 2: God began to exist.
Conclusion: Therefore, God has a cause of his/her beginning to exist.

This argument is not successful because monotheists are not going to accept Premise 2. The monotheistic religions holds that God has always existed.

Premise 1: Everything that begins to exist has a cause of it's beginning to exist.
Premise 3: The universe began to exist.
Conclusion: Therefore, the universe has a cause of it's beginning to exist.

This argument is not successful because philosophical naturalists are not going to accept Premise 3. They hold that the universe, defined as all of time and space, has always existed. For them, there was no place "outside of" or moment "before" the universe.

There are an almost endless set of arguments whose conclusion is that God does or does not exist. But if one of the premises of an argument is rejected for what are good reasons then the argument fails. For example, your assertion that
"God's nature is infinite, and human perception and expression is finite, we can never fully contain or represent God"
is a premise that I believe I have good reasons to reject. By the same token, you no doubt think you have good reasons for accepting this premise. If the reasons for and against the premise are good ones, that is are not obviously fallacious or trivial, then it's seems that we have at least prima facie grounds for a genuine dispute whose outcome is pending. Because I am committed to there being no God, there are premises that I am not going to agree to. Vice versa, because you are committed to the existence of God, there are premises you will accept.

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Re: Argument from contradiction

Post #7

Post by elphidium55 »

my bad:
"uprising" overlap should be "suprising" overlap

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Re: Argument from contradiction

Post #8

Post by emilynghiem »

elphidium55 wrote: Sat Jun 06, 2020 8:36 pm @emilyngheim:
Your argument is a bit hard to follow. Also, you make a couple of moves which are a bit dodgy. However, I think that you are on to something important. Let me sketch out an idea that I find congenial that may have some uprising overlap with your point of view.

Note: this is not my original idea but instead follows from some ideas put forward by the Australian philosopher Graham Oppy.

1: There are, as yet, no successful arguments either for or against the question of the existence of God.

2. Given that this question of the existence of God has been debated inconclusively for over 2500 years, it is very unlikely that there will be a successful argument pro or con about this question in the foreseeable future.

Some definitions:
by God I mean the omnipotent, omniscient, omnibenevolent god as generally described by the monotheistic religions;

by argument I mean arguments that are competent, that is we are putting forward arguments which are the best versions of the themselves;

by successful argument, I mean an argument that is so convincing, that upon being presented with it, an open-minded, rational, and well-informed thinker should be required to change their opinion on this question. In other words, a successful argument should compel an intellectually honest atheist to become a theist or an intellectually honest theist to become an atheist.

Why do we not have any such successful arguments? Consider the following two arguments.

Premise 1: Everything that begins to exist has a cause of it's beginning to exist.
Premise 2: God began to exist.
Conclusion: Therefore, God has a cause of his/her beginning to exist.

This argument is not successful because monotheists are not going to accept Premise 2. The monotheistic religions holds that God has always existed.

Premise 1: Everything that begins to exist has a cause of it's beginning to exist.
Premise 3: The universe began to exist.
Conclusion: Therefore, the universe has a cause of it's beginning to exist.

This argument is not successful because philosophical naturalists are not going to accept Premise 3. They hold that the universe, defined as all of time and space, has always existed. For them, there was no place "outside of" or moment "before" the universe.

There are an almost endless set of arguments whose conclusion is that God does or does not exist. But if one of the premises of an argument is rejected for what are good reasons then the argument fails. For example, your assertion that
"God's nature is infinite, and human perception and expression is finite, we can never fully contain or represent God"
is a premise that I believe I have good reasons to reject. By the same token, you no doubt think you have good reasons for accepting this premise. If the reasons for and against the premise are good ones, that is are not obviously fallacious or trivial, then it's seems that we have at least prima facie grounds for a genuine dispute whose outcome is pending. Because I am committed to there being no God, there are premises that I am not going to agree to. Vice versa, because you are committed to the existence of God, there are premises you will accept.
Dear @elphidium55
Let's start by separating two parts of this process,
which I see more as a "reconciliation" process than trying to "prove what God is or isn't"
A. first, definitions or meaning of God,
Are you okay with both of these being acceptable if people believe in God this way
1. First God not having a beginning or end, but being infinite
such as all Life or the Universe "self-existent" where it just is.
Always has been and always will be.
2. God meaning a Personal authority
where this God does have a beginning and a process of manifesting to man
3. People not using God, but believing in general
laws in life, nature or physics, and believing those
LAWS are already in existence and universal to all people (regardless of 1 or 2)

Are you okay with people believing in either one,
and it doesn't have to mean to argue in conflict which way God is to people?

B. Process of reconciling between people who think more like 1, 2 or 3

Again, INSTEAD of arguing trying to prove or disprove 1, 2 or 2 (or any variation of these)

I believe we can prove that a PROCESS is going on where people (who might use 1, 2 or 3)
are merely trying to RECONCILE and establish common understanding of truth
REGARDLESS of these differences.

The "proof" I seek is not so much WHETHER OR NOT we can EVER prove (or disprove) 1, 2 3 etc.
But to come to an understanding of the reconciliation process.

And THIS is where I believe we can show the steps in Christianity
match the steps of reconcilation REGARDLESS if people are believers, nonbelievers, theists or nontheists,
Christians or nonchristians.

We all go through a process of FORGIVING conflicts or issues first
before we can RESOLVE them.

I am proposing to study this process and prove that it works!

By teaching people that FORGIVENESS correlates with ability to reconcile and communicate/cooperate
REGARDLESS of the differences in beliefs (which may or may not change literally)
And by teaching that UNFORGIVENESS correlates with FAILURE to resolve relations and conflicts,
we can encourage more people to seek Forgiveness and Healing

Then, as the process goes, as more people HEAL by forgiveness,
this improves mind, heart and relations between people
so we communicate and establish common truth and understanding.

The same process in Christianity can still happen
even if we do not change each other's LANGUAGE or perceptions of God being 1, 2 3 or something else.

So we still work through the details in A in order to communicate.

But the REAL process of establishing understanding of God is in B:
The REAL proof is actually proving that forgiveness helps resolve and heal relationships.
And it isn't about trying to convert Christians to atheism or Atheists to Christianity to make peace.

We CAN demonstrate that by physical science and "proof" by statistical methods:
that FORGIVENESS correlates with healing and success in relationships (between people or between groups)
while UNFORGIVENESS correlates with unresolved conflicts and failure to reach agreements

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Re: Argument from contradiction

Post #9

Post by elphidium55 »

@emilygnheim asks:
Are you okay with both of these being acceptable if people believe in God this way
1. First God not having a beginning or end, but being infinite such as all Life or the Universe "self-existent" where it just is. Always has been and always will be.
2. God meaning a Personal authority where this God does have a beginning and a process of manifesting to man
To which I respond: As a philosophical naturalist, I reject both of these premises. However, I acknowledge that you do accept them and that the reasons you do so are worthy of consideration.

@emilygnheim also says this:
I believe we can prove that a PROCESS is going on where people ... are merely trying to RECONCILE and establish common understanding of truth REGARDLESS of these differences.
To which I respond: Yes -- I believe that we are both engaged in an inquiry aimed ultimately at coming to an understanding of truth. It seems to me that the charitable thing to do in discussions of this sort is to presume good faith on all sides. I think you would agree, which is why I appreciate this conversation. I am firmly in favor of civility and openness between theists and atheists.

However, I am not (yet) convinced that our differing positions on the God question are reconcilable. It seems to me that supernaturalism and naturalism cannot both be true. Which is why I don't think that going through a process of forgiving conflicts or issues on the question of God's existence will lead to a resolution. Perhaps, at the end of the day, the most we can do is agree to disagree.

There is another point to my (ie. Grahm Oppy's) argument that I should lay down here. Although point by point comparisons between supernatural and natural explanations on certain topics may be more a less a draw, in my opinion, naturalism offers a better overall explanation of things. It is simpler in that it comes with a lot less metaphysical baggage for the same amount of explanatory success.

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Re: Argument from contradiction

Post #10

Post by Wootah »

Bust Nak wrote: Mon Jun 01, 2020 6:39 am
Wootah wrote: Wed Feb 05, 2020 7:46 pm If you understand these two logical rules you can understand why you don't have to prove something exists to know it exists.
What do you think a proof by contradiction starting with an assumption of non-existence is, if not a proof of existence?
If you understand these two logical rules then you can understand why you don't have to have positive prove something exists to know it exists.

Might be clearer.
Proverbs 18:17 The one who states his case first seems right, until the other comes and examines him.

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