## Let me convince you that none of you are Classical logicians!

What is the basis for reason? And mathematics?

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Logik
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### Re: Let me convince you that none of you are Classical logicians!

Atla wrote: Fri Feb 22, 2019 8:18 pm What bug in reasoning. Every half-decent thinker uses formal logic as a basis.
So fix the argument! Translate it into formal logic such that it doesn't result in a contradiction.
Last edited by Logik on Fri Feb 22, 2019 8:23 pm, edited 1 time in total.
Atla
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Joined: Fri Dec 15, 2017 8:27 am

### Re: Let me convince you that none of you are Classical logicians!

Logik wrote: Fri Feb 22, 2019 8:21 pm
Atla wrote: Fri Feb 22, 2019 8:18 pm What bug in reasoning. Every half-decent thinker uses formal logic as a basis.
So fix the argument! Translate the English into formal logic such that it doesn't result in absurdity.
That's what I started with.

Premise 1. John is human ( A ∈ C )
Premise 2. Jane is human ( B ∈ C )

"John is Jane" therefore does not follow.
Logik
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Joined: Tue Dec 04, 2018 12:48 pm

### Re: Let me convince you that none of you are Classical logicians!

Atla wrote: Fri Feb 22, 2019 8:23 pm That's what I started with.

Premise 1. John is human ( A ∈ C )
Premise 2. Jane is human ( B ∈ C )

"John is Jane" therefore does not follow.
Sure it does.

Here is the code: https://repl.it/repls/SandybrownWretchedConfiguration

As you have insisted: A ∈ C and B ∈ C
And A = B still returns "True"
Atla
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Joined: Fri Dec 15, 2017 8:27 am

### Re: Let me convince you that none of you are Classical logicians!

Logik wrote: Fri Feb 22, 2019 8:34 pm
Atla wrote: Fri Feb 22, 2019 8:23 pm That's what I started with.

Premise 1. John is human ( A ∈ C )
Premise 2. Jane is human ( B ∈ C )

"John is Jane" therefore does not follow.
Sure it does.

Here is the code: https://repl.it/repls/SandybrownWretchedConfiguration

As you have insisted: A ∈ C and B ∈ C
And A = B still returns "True"
What does this program have to do with the argument?

This program only seems to show that two empty sets are the same.
henry quirk
Posts: 9386
Joined: Fri May 09, 2008 8:07 pm

### I'm not a classical logician, but here's my try...

Premise 1. John is human ( A = C )
Premise 2. Jane is human ( B = C )

so: A is B

my fix...

P1: John is a human[man] ( A = C[1] )
P2: Jane is a human[woman] ( B = C[2] )

so: A is not B

I've solved the problem or opened myself to mockery: pick one.
Logik
Posts: 4041
Joined: Tue Dec 04, 2018 12:48 pm

### Re: Let me convince you that none of you are Classical logicians!

Atla wrote: Fri Feb 22, 2019 8:43 pm What does this program have to do with the argument?

This program only seems to show that two empty sets are the same.
Dude. I typed in the argument EXACTLY as you defined it in formal logic.

And the conclusion (which is itself a proposition) A = B evaluates to true.

It is deductively valid.

You said you were going to fix it...
Logik
Posts: 4041
Joined: Tue Dec 04, 2018 12:48 pm

### Re: I'm not a classical logician, but here's my try...

henry quirk wrote: Fri Feb 22, 2019 8:56 pm Premise 1. John is human ( A = C )
Premise 2. Jane is human ( B = C )

so: A is B

my fix...

P1: John is a human[man] ( A = C[1] )
P2: Jane is a human[woman] ( B = C[2] )

so: A is not B

I've solved the problem or opened myself to mockery: pick one.
A for effort!

You are on the right track, but we are going to run into more issues as soon as I define Stephanie, D who is also a woman ( D = C[2])

And then Jane is Stephanie evaluates to true..
Atla
Posts: 3068
Joined: Fri Dec 15, 2017 8:27 am

### Re: Let me convince you that none of you are Classical logicians!

Logik wrote: Fri Feb 22, 2019 8:58 pm
Atla wrote: Fri Feb 22, 2019 8:43 pm What does this program have to do with the argument?

This program only seems to show that two empty sets are the same.
Dude. I typed in the argument EXACTLY as you defined it in formal logic.

And the conclusion (which is itself a proposition) A = B evaluates to true.

It is deductively valid.

You said you were going to fix it...
I don't know Python but I can tell that your program has nothing to do with the argument. Are you really a programmer?

You need to add two different elements to a set and then check whether those two elements are the same.
Logik
Posts: 4041
Joined: Tue Dec 04, 2018 12:48 pm

### Re: Let me convince you that none of you are Classical logicians!

Atla wrote: Fri Feb 22, 2019 9:05 pm I don't know Python but I can tell that your program has nothing to do with the argument. Are you really a programmer?
You will forgive us if we don't trust your instincts over the combined efforts of thousands of logicians over the last 50 years.

If the interpreter doesn't throw an error - the argument is valid.
Atla wrote: Fri Feb 22, 2019 9:05 pm You need to add two different elements to a set and then check whether those two elements are the same.
I did add two different elements. A and B that is these two lines
C.append(A)
C.append(B)
Let me give you a helping hand. I will assign names to the variables. And add another Jane for fun!

https://repl.it/repls/SimpleWrathfulMice
Logik
Posts: 4041
Joined: Tue Dec 04, 2018 12:48 pm

### Re: Let me convince you that none of you are Classical logicians!

I will spare you the pain and suffering.

How often have you heard people say "You are just a number."?

Sadly - it's true. If you want to retain the notion of uniqueness in formal logic - you need to assign a unique identifier to each unique element.
There is no other way. https://en.wikipedia.org/wiki/Unique_identifier

Which means the law of identity is an error. And when you throw it out.... Classical logic falters.
Last edited by Logik on Fri Feb 22, 2019 9:29 pm, edited 1 time in total.
Atla
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Joined: Fri Dec 15, 2017 8:27 am

### Re: Let me convince you that none of you are Classical logicians!

Logik wrote: Fri Feb 22, 2019 9:18 pm
Atla wrote: Fri Feb 22, 2019 9:05 pm I don't know Python but I can tell that your program has nothing to do with the argument. Are you really a programmer?
You will forgive us if we don't trust your instincts over the combined efforts of thousands of logicians over the last 50 years.

If the interpreter doesn't throw an error - the argument is valid.
Atla wrote: Fri Feb 22, 2019 9:05 pm You need to add two different elements to a set and then check whether those two elements are the same.
I did add two different elements. A and B that is these two lines
C.append(A)
C.append(B)
Let me give you a helping hand. I will assign names to the variables. And add another Jane for fun!

https://repl.it/repls/SimpleWrathfulMice
This program checks whether the character string 'Jane' is equal to the character string 'Jane'.

Ffs you aren't even a programmer, you were just making up that one too.
Logik
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Joined: Tue Dec 04, 2018 12:48 pm

### Re: Let me convince you that none of you are Classical logicians!

Atla wrote: Fri Feb 22, 2019 9:28 pm This program checks whether the character string 'Jane' is equal to the character string 'Jane'.

Ffs you aren't even a programmer, you were just making up that one too.
Well what is it supposed to compare, genius?

What does A = A compare ? The law if identity, no?

I am a programmer.
I know how to fix it, but I want YOU to fix it in Classical Logic! I'll even bet you money that you can't!

I'll show you how deep the rabbit hole goes.
Atla
Posts: 3068
Joined: Fri Dec 15, 2017 8:27 am

### Re: Let me convince you that none of you are Classical logicians!

Logik wrote: Fri Feb 22, 2019 9:29 pm
Atla wrote: Fri Feb 22, 2019 9:28 pm This program checks whether the character string 'Jane' is equal to the character string 'Jane'.

Ffs you aren't even a programmer, you were just making up that one too.
Well what is it supposed to compare, genius?

What does A = A compare ? The law if identity, no?

I am a programmer.
I know how to fix it, but I want YOU to fix it in Classical Logic! I'll even bet you money that you can't!

I'll show you how deep the rabbit hole goes.
I may have stopped writing computer programs over a decade ago and don't remember that much, but this is just sad
henry quirk
Posts: 9386
Joined: Fri May 09, 2008 8:07 pm
"A for effort!"

No mockery? Where's my goddamned Nobel Prize!

#

"You are on the right track, but we are going to run into more issues as soon as I define Stephanie, D who is also a woman ( D = C[2]) And then Jane is Stephanie evaluates to true."

As I say, I'm no logician, but this seems to be a language problem (accurate description/placeholding), so all you got to do is keep addin' notations to individual terms...

Steph ( D = C[2]{1} )

Jane ( E = C[2]{2} )

...to get E is not D, C, B, or A, yeah?

As you go through the population you'd end up with outlandishly long, freakish 'placeholdrs' but all entities would be accurately 'filed, stamped, indexed, briefed, debriefed, and numbered!' without any false equivalencies.
Logik
Posts: 4041
Joined: Tue Dec 04, 2018 12:48 pm

### Re:

henry quirk wrote: Fri Feb 22, 2019 9:36 pm "A for effort!"

No mockery? Where's my goddamned Nobel Prize!

#

"You are on the right track, but we are going to run into more issues as soon as I define Stephanie, D who is also a woman ( D = C[2]) And then Jane is Stephanie evaluates to true."

As I say, I'm no logician, but this seems to be a language problem (accurate description/placeholding), so all you got to do is keep addin' notations to individual terms...

Steph ( D = C[2]{1} )

Jane ( E = C[2]{2} )

...to get E is not D, C, B, or A, yeah?

As you go through the population you'd end up with outlandishly long, freakish 'placeholdrs' but all entities would be accurately 'filed, stamped, indexed, briefed, debriefed, and numbered!' without any false equivalencies.
Bingo.

Basically - you have invented ID numbers/Social security numbers.

Good to meet you Henry12341
Last edited by Logik on Fri Feb 22, 2019 9:41 pm, edited 1 time in total.