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All; therefore some?

Do you think all these arguments are valid, only some are, or none of them?

  • These arguments don't make sense.

    Votes: 0 0.0%

  • Total voters
    6
  • Poll closed .
as well as posters who are not biased by a schooling in mathematical logic, which is obviously wrong.

It's not "obviously" anything until you've provided an argument that it is. "I don't like it" is not an argument.

Sure, I'm not making any argument here, I'm just replying to a question. Pragmatics, remember?

I'm not interested proving mathematical logic is junk or that you are wrong. You will be aware that the entirety of the subject probably necessitates more than 10 volumes of one thousand pages each! Life is short and I have no reason to make it a study of the stupidity of other people, particularly when they go in herds of millions. I am interested to see how unbiased souls understand the logical import of everyday sentences. It is somewhat unfortunate that each time I tried to have a decent conversation, the mathematical-logic schooled posters here sort of hijack my thread and boss around other posters, asserting with the typical authority of the ignoramus that they know what is valid and what is not. I grant you that you are making more interesting contributions to the subject, which is a definite improvements on the competition, but the fact remains I won't try to convince you your beliefs in the matter are junk. Remember, you are millions sharing the same dogma and these millions are literally everywhere on the Internet. If you could justify that the mathematical logic take on "all" and "some" that you have advocated was correct, I would be interested, but you obviously cannot do that. Even looking at your explanations about the reasons underpinning how mathematical logic works in this respect confirms my views that it is wrong, though, again, I won't explain. Logic didn't wait for mathematicians to take an interest. Aristotle described for the first time the logic of human beings 2,500 years ago, only partially of course, but he did a great job, and many philosophers are still happy to use Aristotelian logic. It is only in the 19th century that mathematicians started to work on mathematical logic. So, at the very least, you should learn to make the distinction between logic generally and mathematical logic. You are free to believe without foundation that mathematical logic is part of logic, something I scoff at myself, but any claim mathematical logic is all there is to logic would be just a blatant and disgraceful lie.

Still, you're doing well here.
EB
 
as well as posters who are not biased by a schooling in mathematical logic, which is obviously wrong.

It's not "obviously" anything until you've provided an argument that it is. "I don't like it" is not an argument.

Sure, I'm not making any argument here, I'm just replying to a question. Pragmatics, remember?

I'm not interested proving mathematical logic is junk or that you are wrong. You will be aware that the entirety of the subject probably necessitates more than 10 volumes of one thousand pages each! Life is short and I have no reason to make it a study of the stupidity of other people, particularly when they go in herds of millions. I am interested to see how unbiased souls understand the logical import of everyday sentences.

That's an interesting question, but it is a question of natural language semantics and/or pragmatics, not one of logic.

It is somewhat unfortunate that each time I tried to have a decent conversation, the mathematical-logic schooled posters here sort of hijack my thread and boss around other posters, asserting with the typical authority of the ignoramus that they know what is valid and what is not. I grant you that you are making more interesting contributions to the subject, which is a definite improvements on the competition, but the fact remains I won't try to convince you your beliefs in the matter are junk. Remember, you are millions sharing the same dogma and these millions are literally everywhere on the Internet. If you could justify that the mathematical logic take on "all" and "some" that you have advocated was correct, I would be interested, but you obviously cannot do that.

You have fallen for a category error. Logical systems aren't correct or wrong - they are consistent or inconsistent, useful or not.

Even looking at your explanations about the reasons underpinning how mathematical logic works in this respect confirms my views that it is wrong, though, again, I won't explain. Logic didn't wait for mathematicians to take an interest. Aristotle described for the first time the logic of human beings 2,500 years ago, only partially of course, but he did a great job, and many philosophers are still happy to use Aristotelian logic. It is only in the 19th century that mathematicians started to work on mathematical logic. So, at the very least, you should learn to make the distinction between logic generally and mathematical logic. You are free to believe without foundation that mathematical logic is part of logic, something I scoff at myself, but any claim mathematical logic is all there is to logic would be just a blatant and disgraceful lie.

Still, you're doing well here.
EB

False dichotomy. There isn't one "logic" sans 'mathematical' and one mathematical logic. There is dozens of systems of logic. Here's a very incomplete list of some of them: https://en.wikipedia.org/wiki/Non-classical_logic#Examples_of_non-classical_logics, many of which have real applications outside the domains of mathematics or philosophy - I've worked with (variants if) at least two from that list alone and I'm a mere linguist-gone-programmer. However when you say "logic" without a qualifier, people will assume you talk about standard predicate logic. It's called standard for a reason

What all of them have in common is that they define their terms more precisely than natural language, so even if some of its operators superficially resemble words in any or all natural languages, there is going to be edge cases where a logical statement doesn't cleanly translate into a sentence of the language.

You have successfully shown that predicate logic behaves like any other kind of logic in that respect. Well done.
 
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This thread is actually good empirical evidence that replacing a proper formalization of the basics of logic with "just have the terms mean what normal people understand from their everyday language usage" isn't going to get you very far. Even discarding the 50% that, according to you, have been brainwashed by "mathematical logic", the answers evenly split into three different and contradictory options. If you want a replicable system of logic, where different people will come to the same conclusions given the same premises, you have to abstract away from the uncertainties of natural language and make arbitrary decisions some people will find counter-intuitive some of the time. Whether that is standard predicate logic, or any of the hundreds of other systems in existence, or any of the myriad possible systems yet to be posited.

In the context of properly defined logics (note the plural), saying "it's counter-intuitive (to mee), therefore it's wrong" would be hubris if it weren't a category error in the first place. A logic isn't meant to be correct, it's meant to be consistent, and useful.
 
I'm interested in logic.
EB

Would you say that your view of of what is logic arises from  rationalism and tradition?

Not one bit.

My take is to apply the scientific method*, which should have become obvious to all here given my many threads on the subject.

For empirical evidence, I look at Aristotle, the Stoics and the Scholastic, as well as posters who are not biased by a schooling in mathematical logic, which is obviously wrong.

I also take into account my own logical intuition** as perception, in the same way that a scientist has to trust his perception.

You've long been barking up the wrong tree with your "Rationalism". I abide not by Rationalism but by rationality, which I sensibly define as "facts plus logic", and I don't think anyone could fault me for that.
EB

*a method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.

** is a series of instinctive foresight, know-how and savviness often associated with the ability to perceive logical or mathematical truth — and the ability to solve mathematical challenges efficiently.[1][2] Humans apply logical intuition in proving mathematical theorems,[3] validating logical arguments,[4] developing algorithms and heuristics,[5] and in related contexts where mathematical challenges are involved.[6] The ability to recognize logical or mathematical truth and identify viable methods may vary from person to person, and may even be a result of knowledge and experience which are subject to cultivation.[7] The ability may not be realizable in a computer program by means other than genetic programming or evolutionary programming

Your entire post speaks of your rationalistic tendencies. Check out the definition I provided and show me where it says "The scientist trusts his perception".

As for your own logical intuition as perception you're going to have provide operations if you want to join it to an operational definition of perception which I'm taking to be a scientific term of art.

If you manage that I'm sure some of us will be looking forward to your justifications for calling Mathematical Logic "obviously wrong"
 
This thread is actually good empirical evidence that replacing a proper formalization of the basics of logic with "just have the terms mean what normal people understand from their everyday language usage" isn't going to get you very far. Even discarding the 50% that, according to you, have been brainwashed by "mathematical logic", the answers evenly split into three different and contradictory options. If you want a replicable system of logic, where different people will come to the same conclusions given the same premises, you have to abstract away from the uncertainties of natural language and make arbitrary decisions some people will find counter-intuitive some of the time. Whether that is standard predicate logic, or any of the hundreds of other systems in existence, or any of the myriad possible systems yet to be posited.

Sure, I wouldn't expect most people to even understand what they themselves say! I understand perfectly well the limitation of linguistic expression. You're barging in when the doors are wide open.

It is funny to see you jump to conclusion. All you point here is irrelevant. All I did here was to ask a simple question to get people to elicit their logical intuition about the logical relation between "all" and "some". And then you go on inferring all sorts of flaws in my methodology and character! LOL, man, LOL.

In the context of properly defined logics (note the plural), saying "it's counter-intuitive (to mee), therefore it's wrong" would be hubris if it weren't a category error in the first place. A logic isn't meant to be correct, it's meant to be consistent, and useful.

Ah, you are equivocating because you are confusing.

There is logic and logic.

There is logic as formal logic as a model of logic as the logic of the human mind. This one, formal logic, needs to be correct, otherwise it's not even a correct model of the logic of the human mind.

Then there is the logic of the human mind that we try to apply in what we do and what we say. And, yes, our application of logic needs to be logical, that is, it needs to be consistent. And it is obviously not a model. It is an application of the logic of the human mind and as such it may and often is faulty and therefore inconsistent.

There, you've learned something.
EB
 
False dichotomy. There isn't one "logic" sans 'mathematical' and one mathematical logic. There is dozens of systems of logic. Here's a very incomplete list of some of them: https://en.wikipedia.org/wiki/Non-classical_logic#Examples_of_non-classical_logics, many of which have real applications outside the domains of mathematics or philosophy - I've worked with (variants if) at least two from that list alone and I'm a mere linguist-gone-programmer. However when you say "logic" without a qualifier, people will assume you talk about standard predicate logic. It's called standard for a reason

No, there is just one true logic, which is the deductive logic of the huma brain. Mathematicians are free to equivocate and there is nothing I can do about that, but mathematical logic is just toy logic for children. It doesn't work as logic. You don't even understand what it is in reality.

What all of them have in common is that they define their terms more precisely than natural language, so even if some of its operators superficially resemble words in any or all natural languages, there is going to be edge cases where a logical statement doesn't cleanly translate into a sentence of the language.

No, mathematical logic is mathematics and nothing else.

OK, I think we've run out of things to say. Thanks for your patience and your relative civility, at least compared to other people here. And you actually said a few interesting things! Thanks for that, too.
EB
 
I might address the rest at a later point, here's just a quick reminder that I haven't attacked your character.

You're the one calling every one else stupid for not agreeing with the latest random thing you claim.
 
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For the sake of the argument, let's say you are right that there is "just one true logic" (even though you aren't): inferring anything about it by asking people about the relationships between potentially ambiguous linguistic constructions without as much as clarifying which meaning you're after is still going to be a fruitless exercise that tells you nothing about that logic.
 
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Ah, here is a very interesting piece of logic. I give the general form of the argument first, and then three straightforward applications of the general form.

All A's are/have F;
Therefore, some A is/has F.

All angels have wings;
Therefore, some angel has wings.

All politicians are liars;
Therefore, some politician is a liar.

All imaginary beings have serious existential problems;
Therefore, some imaginary being has serious existential problems.

Thank you to say whether you think all these arguments are valid, or only some, or none.

Thank you to cast your vote before posting any comment.
EB
I didn't vote, because to my understanding there is a difference between valid formal logic, which all the syllogism have, and a valid argument, which is what your question asks about, and which depends not just on the validity of the formal logic but on the truth or accuracy of the premises.
However, it is not clear to me whether you are not just using "argument" as a synonym for "formal logic".
 
I didn't vote, because to my understanding there is a difference between valid formal logic, which all the syllogism have, and a valid argument, which is what your question asks about, and which depends not just on the validity of the formal logic but on the truth or accuracy of the premises.
However, it is not clear to me whether you are not just using "argument" as a synonym for "formal logic".

Definition
A valid argument is a logical argument in which the premises provide conclusive reasons for the conclusion.

When a proof is valid, we may say one of the following:

  • The conclusion follows from the premises;
  • The premises entail the conclusion;
  • The conclusion is true on the strength of the premises;
  • The conclusion is drawn from the premises;
  • The conclusion is deduced from the premises;
  • The conclusion is derived from the premises.

https://proofwiki.org/wiki/Definition:Valid_Argument

I hope this will be helpful.
EB
 
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