## Poll on the validity of two arguments

What is the basis for reason? And mathematics?

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## Are these two arguments valid?

1st argument - Valid
4
25%
1st argument - Not valid
3
19%
1st argument - I don't know
1
6%
1st argument - The argument doesn't make sense
1
6%
2nd argument - Valid
4
25%
2nd argument - Not valid
3
19%
2nd argument - I don't know
0
2nd argument - The argument doesn't make sense
0

Speakpigeon
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### Re: Poll on the validity of two arguments

Logik wrote: Tue Jan 22, 2019 9:06 pm Lets assume B is made up of 100 parts.
Let A be the state of any one of those parts: Ba
Let C be determined by the state of part: Bc

Without any further information the probability of Ba coinciding with Bc is 1/100.

There is a 99% chance the conclusion is false (and therefore the argument is invalid)
And 1% chance the conclusion is true (and therefore the argument is valid).

The fewer parts B has - the higher the probability of this being a valid argument.
The more parts B has - the lower the probability of this being a valid argument.
Yes, excellent!
And so uncertainty will depend on what we substitute A, B and C with. But in the form the argument has here, there can't be any uncertainty at to validity. The argument is valid or it is invalid. And there is no uncertainty about soundness until you specify what you substitute A, B and C with.
EB
Logik
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### Re: Poll on the validity of two arguments

Speakpigeon wrote: Tue Jan 22, 2019 9:55 pm Yes, excellent!
And so uncertainty will depend on what we substitute A, B and C with. But in the form the argument has here, there can't be any uncertainty at to validity. The argument is valid or it is invalid.
The logical compliment of this argument is also valid, which makes it a truism.

The criteria for deductive validity are pretty clear.

An argument is deductively valid if and only if it's impossible for the premisses to be true but the conclusion to be false.
On this criterion alone the argument is not deductively valid because there is non-zero probability for the premises to be true but the conclusion to be false.

It is inductively valid. But then, there really is no such thing as an inductively invalid argument.
Speakpigeon wrote: Tue Jan 22, 2019 9:55 pm The argument is valid or it is invalid.
False dichotomy. That is precisely what the decidability criterion is about. The missing option is "the validity if this argument is undecidable".
Speakpigeon
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### Re: Poll on the validity of two arguments

Logik wrote: Tue Jan 22, 2019 9:23 pm Time to bow out of the intellectual paralympics.
If there is an invalid here it's you since you're unable to assess the validity of a simple argument.
EB
Logik
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### Re: Poll on the validity of two arguments

Speakpigeon wrote: Tue Jan 22, 2019 10:06 pm If there is an invalid here it's you since you're unable to assess the validity of a simple argument.
And you are only able to assess the validity of your argument because you don't understand decision theory, the decidability criterion and their implications.

By the way - I sell coins that can determine the validity of any argument (correctness not guaranteed). Are you interested? Only \$49.99 each.
Last edited by Logik on Tue Jan 22, 2019 10:10 pm, edited 1 time in total.
bahman
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### Re: Poll on the validity of two arguments

Logik wrote: Tue Jan 22, 2019 9:51 pm
Speakpigeon wrote: Tue Jan 22, 2019 9:44 pm "May" isn't about "chance", it's about knowledge and uncertainty, as signalled by the phrase "For all we know".
Since you appear to be exercising Cunningham's law...

https://en.wikipedia.org/wiki/Uncertainty#Concepts
Measurement of uncertainty
A set of possible states or outcomes where probabilities are assigned to each possible state or outcome – this also includes the application of a probability density function to continuous variables.[2]
Yes. I couldn't say it better than you.
bahman
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### Re: Poll on the validity of two arguments

Logik wrote: Tue Jan 22, 2019 9:51 pm
Speakpigeon wrote: Tue Jan 22, 2019 9:44 pm "May" isn't about "chance", it's about knowledge and uncertainty, as signalled by the phrase "For all we know".
Since you appear to be exercising Cunningham's law...

https://en.wikipedia.org/wiki/Uncertainty#Concepts
Measurement of uncertainty
A set of possible states or outcomes where probabilities are assigned to each possible state or outcome – this also includes the application of a probability density function to continuous variables.[2]
Yes. I couldn't say it better than you.
Speakpigeon
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Location: Paris, France, EU

### Re: Poll on the validity of two arguments

Logik wrote: Tue Jan 22, 2019 10:03 pm False dichotomy. That is precisely what the decidability criterion is about. The missing option is "the validity if this argument is undecidable".
But it is decidable. Two people here and more elsewhere can decide that the argument is valid.
What you would need to do is prove the argument invalid. Not something really possible but to be coherent, you would need to try to prove it.
The way to prove an argument invalid is pretty straightforward.
That you can't do it may be because the argument is valid and you could prove it invalid if it was invalid or because the argument is valid and you couldn't prove it invalid even if it was invalid.
I will have to live with the fact that I will never know which.
EB
Logik
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### Re: Poll on the validity of two arguments

Speakpigeon wrote: Tue Jan 22, 2019 10:13 pm But it is decidable. Two people here and more elsewhere can decide that the argument is valid.
So can a coin.

But it's wrong 50% of the time.

Like I said - I'll sell you one. Only \$49.99!

To disprove your argument all I need is a truth-table for "MAY". Which you will naturally not provide, because you'll have to wipe the egg off your face.
Speakpigeon
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### Re: Poll on the validity of two arguments

bahman wrote: Tue Jan 22, 2019 10:10 pm
Logik wrote: Tue Jan 22, 2019 9:51 pm Uncertainty is all about probability. https://en.wikipedia.org/wiki/Uncertainty#Concepts
Measurement of uncertainty
A set of possible states or outcomes where probabilities are assigned to each possible state or outcome – this also includes the application of a probability density function to continuous variables.[2]
Yes. I couldn't say it better than you.
Yet his claim is wrong and merely shows a lack of formal education. Uncertainty is not ALL about probability.
Uncertain primarily means unknown, and this because knowledge brings certainty.
His definition is essentially that used in the context of science.Yet, even there his claim is false. It is uncertain that dark matter is matter at all. No probabilities there, even though it's a scientific question.
EB
Logik
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Joined: Tue Dec 04, 2018 12:48 pm

### Re: Poll on the validity of two arguments

Speakpigeon wrote: Tue Jan 22, 2019 10:26 pm Yet his claim is wrong and merely shows a lack of formal education. Uncertainty is not ALL about probability.
Uncertainty is all about probability If you paid for this "formal education" you should ask for a refund.

My definition is used in any epistemic field. Which, naturally, excludes most of academia.
Speakpigeon
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### Re: Poll on the validity of two arguments

Logik wrote: Tue Jan 22, 2019 10:14 pm To disprove your argument all I need is a truth-table for "MAY". Which you will naturally not provide, because you'll have to wipe the egg off your face.
And you don't have it so you can't claim the argument is invalid, so you keep sniping from the sidelines.
And by the way, truth tables for the conjunction, disjunction and negation have all been established on the basis of the intuition of human beings. That's all there is to decide what logical truths there are and therefore what truth tables should be.
Except for the so-called material implication, which doesn't fit with our intuition of the logical implication.
At best, the material implication is a gross approximation of the logical implication. So, you can keep your truth tables, me, I trust 525 million years of evolution as guarantor of our logic rather than a bunch a mathematicians working for two paltry millennia and opting for expediency.
EB
Speakpigeon
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Location: Paris, France, EU

### Re: Poll on the validity of two arguments

Logik wrote: Tue Jan 22, 2019 10:34 pm
Speakpigeon wrote: Tue Jan 22, 2019 10:26 pm Yet his claim is wrong and merely shows a lack of formal education. Uncertainty is not ALL about probability.
Uncertainty is all about probability If you paid for this "formal education" you should ask for a refund.
My definition is used in any epistemic field. Which, naturally, excludes most of academia.
My definition is used in the whole world.
EB
Speakpigeon
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### Re: Poll on the validity of two arguments

Anyway, thanks for you contribution, which is obviously now spent.
EB
Logik
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### Re: Poll on the validity of two arguments

Speakpigeon wrote: Tue Jan 22, 2019 10:37 pm My definition is used in the whole world.
Bandwagon fallacy?

Naturally.
Logik
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### Re: Poll on the validity of two arguments

Speakpigeon wrote: Tue Jan 22, 2019 10:36 pm
Logik wrote: Tue Jan 22, 2019 10:14 pm To disprove your argument all I need is a truth-table for "MAY". Which you will naturally not provide, because you'll have to wipe the egg off your face.
And you don't have it so you can't claim the argument is invalid, so you keep sniping from the sidelines.
And by the way, truth tables for the conjunction, disjunction and negation have all been established on the basis of the intuition of human beings. That's all there is to decide what logical truths there are and therefore what truth tables should be.
Except for the so-called material implication, which doesn't fit with our intuition of the logical implication.
At best, the material implication is a gross approximation of the logical implication. So, you can keep your truth tables, me, I trust 525 million years of evolution as guarantor of our logic rather than a bunch a mathematicians working for two paltry millennia and opting for expediency.
EB
Pretty ironic. Since our intuition is biased in certain way precisely so as to guarantee our survival using expedient heuristics.
https://en.wikipedia.org/wiki/Thinking,_Fast_and_Slow

If our intuition was any good at avoiding making logical and methodical errors we wouldn't need so much rigour in science.