## POLL 3 on the validity of a simple argument on Joe the Squid

What is the basis for reason? And mathematics?

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## Is the argument valid?

No
1
100%
Yes
0
I don't know
0
The argument doesn't make sense
0

Age
Posts: 2324
Joined: Sun Aug 05, 2018 8:17 am

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Speakpigeon wrote:
Sat Jan 26, 2019 3:15 pm
surreptitious57 wrote:
Sat Jan 26, 2019 2:32 pm
Because the conclusion is not true in relation to all of the premises only some of them
That would be irrelevant. For example:
x is A
y is B
B is C
Therefore, y is C
Isn't that valid even though the first premise is irrelevant to the conclusion?
surreptitious57 wrote:
Sat Jan 26, 2019 2:32 pm
The conclusion and final premise contradict each other and so the argument is invalid
In real life, yes, but you have to assess the validity of an logical argument on the basis of what the premises and the conclusion mean and assuming they are true, not on whether they are actually true or false.
If this was the logical process and formula for assessing the validity of a so called "logical argument", then EVERY time we would just assume that the premises and conclusion are true, therefore EVERY time we assess a so called "logical argument" for validity we would deduce, come to the conclusion, and find them valid. The absurdity of this is strikingly obviously.
Speakpigeon wrote:
Sat Jan 26, 2019 3:15 pm
So, in this case, you can't just assume that an elephant is not a squid. And so, you can't assess the validity of the argument on the basis of the last premise and the conclusion alone. You need also need premise 3 that says "An elephant is not a squid".
EB
So, as I said: Your argument is NOT logically valid, now what is the point of this?

Speakpigeon
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Location: Paris, France, EU

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Atla wrote:
Sat Jan 26, 2019 2:52 pm
Speakpigeon wrote:
Sat Jan 26, 2019 2:09 pm
So, you don't go with the definition of validity that they favour in "classical" mathematical logic which implies that the argument is valid because its premises are necessarily false?
Well.. I can't even make sense of this: "the argument is valid because its premises are necessarily false". The argument is valid because it's unsound? Does not follow.
Yep, good way to put it.
So, what do you think of this definition of validity provided on Wiki:
Validity(logic)
In logic, an argument is valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false.
It is not required for a valid argument to have premises that are actually true, but to have premises that, if they were true, would guarantee the truth of the argument's conclusion.
https://en.wikipedia.org/wiki/Validity_(logic)
Reading the first sentence, the argument is definitely valid.
Reading the second sentence, as per your interpretation, I think, the argument seems invalid.
Atla wrote:
Sat Jan 26, 2019 2:52 pm
I guess I keep it simple: I only work with true premises and use simple one-step classical logic on them, or some sort of one-step probabilistic/fuzzy logic.
Yes, I agree it's simple.

Given that the definition of validity in "classical" mathematical logic is one that implies that the argument is valid because its premises are necessarily false and as such is contradicting the conventional view of validity, the one you seem to agree with, which seems in line with Aristotle, it seems to me that the only reason most mathematicians today support this definition is because it had been tailored from the start to fit the definition of the material implication proposed by Russell and accepted by most mathematicians today, I presume.
EB

Speakpigeon
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Location: Paris, France, EU

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Age wrote:
Sat Jan 26, 2019 3:09 pm
This highlights, and shows, more of your inabilities. Either you know all along that your so called "simple argument" is obviously logically invalid, you have just realized this, or you are under some sort of illusion that it is in fact logically valid.
You seem to be under the illusion that you can start by abusing and bullshitting people and then get something from them. Whoa. Get down to Earth, chicken.
EB

Speakpigeon
Posts: 957
Joined: Sat Nov 11, 2017 3:20 pm
Location: Paris, France, EU

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Age wrote:
Sat Jan 26, 2019 3:18 pm
Atla wrote:
Sat Jan 26, 2019 3:11 pm
You however pull "universal knowledge truths" out of your backside, and you think they are coming from God/the universe/whatever.
If that is what you think and believe, then that is fair enough.
Good, that does put some context on things.
Next time, just address the OP as it stands without gratuitously questioning the motives, the morality or the intellect of the poster.
If you can't get yourself to do that, just go talk bullshit elsewhere.
EB

Speakpigeon
Posts: 957
Joined: Sat Nov 11, 2017 3:20 pm
Location: Paris, France, EU

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Age wrote:
Sat Jan 26, 2019 3:29 pm
Speakpigeon wrote:
Sat Jan 26, 2019 3:15 pm
In real life, yes, but you have to assess the validity of an logical argument on the basis of what the premises and the conclusion mean and assuming they are true, not on whether they are actually true or false.
EVERY time we would just assume that the premises and conclusion are true, therefore EVERY time we assess a so called "logical argument" for validity we would deduce, come to the conclusion, and find them valid.

Good point, I corrected my post.
Age wrote:
Sat Jan 26, 2019 3:29 pm
The absurdity of this is strikingly obviously.
Yeah, and "strikingly obviously" is a strikingly obviously meaningless typo.
You should come down to Earth, Angel.
EB

Age
Posts: 2324
Joined: Sun Aug 05, 2018 8:17 am

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Speakpigeon wrote:
Sat Jan 26, 2019 3:41 pm
Age wrote:
Sat Jan 26, 2019 3:09 pm
This highlights, and shows, more of your inabilities. Either you know all along that your so called "simple argument" is obviously logically invalid, you have just realized this, or you are under some sort of illusion that it is in fact logically valid.
You seem to be under the illusion that you can start by abusing and bullshitting people and then get something from them. Whoa. Get down to Earth, chicken.
EB
What are you on about?

I STARTED by asking you and saying :

Is the argument logically valid?
Either way, please articulate why

WHERE is the "abusing" and "bullshitting people" in there?

The ONLY thing that I was trying to get from you is what you are trying to get from others.

Age
Posts: 2324
Joined: Sun Aug 05, 2018 8:17 am

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Speakpigeon wrote:
Sat Jan 26, 2019 3:47 pm
Age wrote:
Sat Jan 26, 2019 3:18 pm
Atla wrote:
Sat Jan 26, 2019 3:11 pm
You however pull "universal knowledge truths" out of your backside, and you think they are coming from God/the universe/whatever.
If that is what you think and believe, then that is fair enough.
Good, that does put some context on things.
Next time, just address the OP as it stands without gratuitously questioning the motives, the morality or the intellect of the poster.
If you can't get yourself to do that, just go talk bullshit elsewhere.
EB
If this is directed at me, then I did address the op, AFTER I gained confirmation if you would or could do what you were expecting others to do. You obviously would not or could not do what you expected others to do, so then I proceeded to point out and show how your so called "simple argument" is NOT logically valid. I have even asked you what is the point of this, which you also failed to answer.

Age
Posts: 2324
Joined: Sun Aug 05, 2018 8:17 am

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Speakpigeon wrote:
Sat Jan 26, 2019 3:57 pm
Age wrote:
Sat Jan 26, 2019 3:29 pm
Speakpigeon wrote:
Sat Jan 26, 2019 3:15 pm
In real life, yes, but you have to assess the validity of an logical argument on the basis of what the premises and the conclusion mean and assuming they are true, not on whether they are actually true or false.
EVERY time we would just assume that the premises and conclusion are true, therefore EVERY time we assess a so called "logical argument" for validity we would deduce, come to the conclusion, and find them valid.

Good point, I corrected my post.
Age wrote:
Sat Jan 26, 2019 3:29 pm
The absurdity of this is strikingly obviously.
Yeah, and "strikingly obviously" is a strikingly obviously meaningless typo.
You should come down to Earth, Angel.
EB
I did NOT even notice your so called "meaningless typo".

By the way I think you have completely misunderstood what I was getting at because you have NOT corrected your post in regards to what I was referring to.

Speakpigeon
Posts: 957
Joined: Sat Nov 11, 2017 3:20 pm
Location: Paris, France, EU

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Age wrote:
Sat Jan 26, 2019 4:09 pm
Speakpigeon wrote:
Sat Jan 26, 2019 3:41 pm
Age wrote:
Sat Jan 26, 2019 3:09 pm
This highlights, and shows, more of your inabilities. Either you know all along that your so called "simple argument" is obviously logically invalid, you have just realized this, or you are under some sort of illusion that it is in fact logically valid.
You seem to be under the illusion that you can start by abusing and bullshitting people and then get something from them. Whoa. Get down to Earth, chicken.
EB
What are you on about?

I STARTED by asking you and saying :

Is the argument logically valid?
Either way, please articulate why
And I replied.
This is my thread.
This thread asks a simple question. So, either you think you know the answer and you just vote before posting any comment, or you don't have a view and you can go play in the courtyard.
And if you want to know what I think, you can start your own thread and see what happens.
That was to the point.
Age wrote:
Sat Jan 26, 2019 4:09 pm
WHERE is the "abusing" and "bullshitting people" in there?
Whoa. Short memory.
It's you here:
Age wrote:
Sat Jan 26, 2019 3:09 pm
This highlights, and shows, more of your inabilities.
It's you again here:
Age wrote:
Sat Jan 26, 2019 2:01 pm
One could also suggest that some are not capable of doing what they are expecting others to do here.
It's also you here:
Age wrote:
Sat Jan 26, 2019 2:16 pm
Go where? Somewhere else, so I do NOT show your inadequacies here?
And again here:
Age wrote:
Sat Jan 26, 2019 3:01 pm
Are you trying to derail from the fact that you are incapable of doing what you are expecting others to do here, or that you just do not want to do what you expect others to do here?
So, abuse and bullshitting.
Age wrote:
Sat Jan 26, 2019 4:09 pm
The ONLY thing that I was trying to get from you is what you are trying to get from others.
And I replied. This thread asks a simple question. So, either you think you know the answer and you just vote before posting any comment, or you don't have a view and you can go play in the courtyard.
And if you want to know what I think, you can start your own thread and see what happens.
EB

Speakpigeon
Posts: 957
Joined: Sat Nov 11, 2017 3:20 pm
Location: Paris, France, EU

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Age wrote:
Sat Jan 26, 2019 4:26 pm
By the way I think you have completely misunderstood what I was getting at because you have NOT corrected your post in regards to what I was referring to.
Then explain again.
If you can't be bothered, it's fine.
EB

Age
Posts: 2324
Joined: Sun Aug 05, 2018 8:17 am

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Speakpigeon wrote:
Sat Jan 26, 2019 4:36 pm
Age wrote:
Sat Jan 26, 2019 4:09 pm
Speakpigeon wrote:
Sat Jan 26, 2019 3:41 pm

You seem to be under the illusion that you can start by abusing and bullshitting people and then get something from them. Whoa. Get down to Earth, chicken.
EB
What are you on about?

I STARTED by asking you and saying :

Is the argument logically valid?
Either way, please articulate why
And I replied.
This is my thread.
This thread asks a simple question. So, either you think you know the answer and you just vote before posting any comment, or you don't have a view and you can go play in the courtyard.
And if you want to know what I think, you can start your own thread and see what happens.
That was to the point.
Age wrote:
Sat Jan 26, 2019 4:09 pm
WHERE is the "abusing" and "bullshitting people" in there?
Whoa. Short memory.
It's you here:
Age wrote:
Sat Jan 26, 2019 3:09 pm
This highlights, and shows, more of your inabilities.
It's you again here:
Age wrote:
Sat Jan 26, 2019 2:01 pm
One could also suggest that some are not capable of doing what they are expecting others to do here.
It's also you here:
Age wrote:
Sat Jan 26, 2019 2:16 pm
Go where? Somewhere else, so I do NOT show your inadequacies here?
And again here:
Age wrote:
Sat Jan 26, 2019 3:01 pm
Are you trying to derail from the fact that you are incapable of doing what you are expecting others to do here, or that you just do not want to do what you expect others to do here?
So, abuse and bullshitting.
Age wrote:
Sat Jan 26, 2019 4:09 pm
The ONLY thing that I was trying to get from you is what you are trying to get from others.
And I replied. This thread asks a simple question. So, either you think you know the answer and you just vote before posting any comment, or you don't have a view and you can go play in the courtyard.
And if you want to know what I think, you can start your own thread and see what happens.
EB
I STARTED by asking YOU the exact same question you ask others.

You FAILED to answer that. I GOT what I wanted in the beginning.

I certainly did NOT "start" doing any thing to get you to do any thing.

You had ALREADY proven what you are capable of, to me, or not capable of some might say.

As soon as you SHOWED that you were NOT going to do what you were asking others to do. I went straight on to doing what you were asking us to do. That is; I pointed out your argument is NOT logically valid.

Now, was there any real point in me doing this?

Age
Posts: 2324
Joined: Sun Aug 05, 2018 8:17 am

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Speakpigeon wrote:
Sat Jan 26, 2019 4:43 pm
Age wrote:
Sat Jan 26, 2019 4:26 pm
By the way I think you have completely misunderstood what I was getting at because you have NOT corrected your post in regards to what I was referring to.
Then explain again.
If you can't be bothered, it's fine.
EB
It is NO bother.

If we are to ASSUME that the premises are true, and not on whether the premises are actually true or false, then EVERY time we looked at an argument to access if the argument is a valid argument or not, then we would ALWAYS arrive at the same conclusion.

Skip
Posts: 2551
Joined: Tue Aug 09, 2011 1:34 pm

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

All arguments are logically valid, as long as you don't care whether words have valid meaning and usage.

Atla
Posts: 1889
Joined: Fri Dec 15, 2017 8:27 am

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Speakpigeon wrote:
Sat Jan 26, 2019 3:35 pm
Atla wrote:
Sat Jan 26, 2019 2:52 pm
Speakpigeon wrote:
Sat Jan 26, 2019 2:09 pm
So, you don't go with the definition of validity that they favour in "classical" mathematical logic which implies that the argument is valid because its premises are necessarily false?
Well.. I can't even make sense of this: "the argument is valid because its premises are necessarily false". The argument is valid because it's unsound? Does not follow.
Yep, good way to put it.
So, what do you think of this definition of validity provided on Wiki:
Validity(logic)
In logic, an argument is valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false.
It is not required for a valid argument to have premises that are actually true, but to have premises that, if they were true, would guarantee the truth of the argument's conclusion.
https://en.wikipedia.org/wiki/Validity_(logic)
Reading the first sentence, the argument is definitely valid.
Reading the second sentence, as per your interpretation, I think, the argument seems invalid.
Atla wrote:
Sat Jan 26, 2019 2:52 pm
I guess I keep it simple: I only work with true premises and use simple one-step classical logic on them, or some sort of one-step probabilistic/fuzzy logic.
Yes, I agree it's simple.

Given that the definition of validity in "classical" mathematical logic is one that implies that the argument is valid because its premises are necessarily false and as such is contradicting the conventional view of validity, the one you seem to agree with, which seems in line with Aristotle, it seems to me that the only reason most mathematicians today support this definition is because it had been tailored from the start to fit the definition of the material implication proposed by Russell and accepted by most mathematicians today, I presume.
EB
Guess so, I don't know much about this, so I may be writing bollocks. I avoid Western philosophers.
Although I studied computer sciences for a few years, and learned mathematical logic, I for example have no idea what the hell this is supposed to mean:
The truth table associated with the material conditional p->q is identical to that of ¬p∨q.

p q p->q
T T T
T F F
F T T
F F T
I vaguely remember having to memorize this truth table line by line because half of it makes no sense to me.

Speakpigeon
Posts: 957
Joined: Sat Nov 11, 2017 3:20 pm
Location: Paris, France, EU

### Re: POLL 3 on the validity of a simple argument on Joe the Squid

Atla wrote:
Sat Jan 26, 2019 5:55 pm
Guess so, I don't know much about this, so I may be writing bollocks. I avoid Western philosophers.
I would be interested in whatever could provide empirical evidence of our logical intuitions, say e.g. Modus ponens, A ⊢ (A ∨ B), or (A ∧ B) ⊢ (A ∨ B). Most people with a training in formal logic will be inevitably biased but a non-Western tradition may be very interesting in this respect.
Atla wrote:
Sat Jan 26, 2019 5:55 pm
Although I studied computer sciences for a few years, and learned mathematical logic, I for example have no idea what the hell this is supposed to mean:
The truth table associated with the material conditional p->q is identical to that of ¬p∨q.

p q p->q
T T T
T F F
F T T
F F T
I vaguely remember having to memorize this truth table line by line because half of it makes no sense to me.
Laugh! I had my first introduction to formal logic when I was 19 years old, at university. And I just experienced something very similar. I was listening to the guy explaining truth tables. Everything was going smoothly with the conjunction, the disjunction, the exclusive disjunction, the negation, the equivalence... And then we got to the truth table of the implication. I was just looking at the truth table he had written on the blackboard and my brain just puked. OK, I thought, that's seriously wrong. It's only much later that I realised most people felt the same (excluding the biased "trained" brain-washed). One author I read also admitted many students protested at the material implication.
Still, we can take the material implication as an approximation of the real logical implication. I'm sure you will accept that the first two lines of its truth table seem to say something true about it.
I also think that, at the time, mathematicians didn't have the resources to produce a better definition. The "tragedy", though, is that since then, generations of students, and therefore mathematicians, have been taught the dogma of the material implication and probably look down on Aristotle as "wishy-washy philosophy". Modern mathematical logic should have been called "theory of material formal logic", rather than the misleadingly dishonest "classical logic".
Still, it's funny to see people with a higher-education in maths systematically opt for a definition of validity in line with the material implication and thereby flunk simple tests like my Joe the Squid argument, whereas the untrained are more likely to get it right, at least those who are not insane.
EB

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