Question about logic.


by Willowz
Tags: logic
Maui
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#55
Nov29-11, 04:55 PM
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Quote Quote by MarcoD View Post
I would think so. The original poster commented on that logic is a byproduct of language, and I wonder whether logic is not a byproduct of a causal understanding of the world.

I agree. And because we don't(and probably won't?) adequately understand anything about the world, 'logic' is probably just a myth and wishful thinking when applied to all aspects of reality. Our mode of thinking(the way we arrive at conclusions) could be faulty or applicable only to specific scales where causality plays an essential role.
Maui
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#56
Nov29-11, 05:10 PM
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Quote Quote by disregardthat View Post
Logic is valid reasoning. It has everything to do with language.

So is valid reasoning an innate biological part of our brains or a defining trait of reality(and its general comprehensibility)? If this will help better illustrate my question - is logic out there(dependencies and correlations waiting to be discovered and understood) or inside us?

I wouldn't agree that valid reasoning is part of language but i could be misunderstanding your point.
disregardthat
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#57
Nov29-11, 05:34 PM
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Quote Quote by Maui View Post
So is valid reasoning an innate biological part of our brains or a defining trait of reality(and its general comprehensibility)? If this will help better illustrate my question - is logic out there(dependencies and correlations waiting to be discovered and understood) or inside us?
We must analyze what logical reasoning is. Inductive reasoning is not logical reasoning. Logical reasoning is, in essence, operations on propositions of language. As such they are part of language and does not transcend it.

The crucial point is that it does not make sense to doubt a logical argument. Logic is determined by the correct usage of logical connectives, such as "and", "or", "not", etc...

Logic is simply the way we treat propositions.

I don't mean that, say, inductive reasoning is wrong, but I do mean that it is not logical.
Maui
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#58
Nov29-11, 05:49 PM
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Quote Quote by disregardthat View Post
We must analyze what logical reasoning is. Inductive reasoning is not logical reasoning. Logical reasoning is, in essence, operations on propositions of language. As such they are part of language and does not transcend it.

No way. Logic is also a part of reality to which you compare to find out if your reasing is faulty or valid. It's reality that decides what reasoning is valid and what is wishful thinking(otherwise we must grant the same status to the Bible as the TOE because they are both expressed in the same language terms).



The crucial point is that it does not make sense to doubt a logical argument. Logic is determined by the correct usage of logical connectives, such as "and", "or", "not", etc...

Logic is simply the way we treat propositions.

I don't mean that, say, inductive reasoning is wrong, but I do mean that it is not logical.


I don't think i have any idea what you mean to say. 2+2=4 is something you can verify against reality, so it's a valid and logical conclusion(you can do the math with apples or stones and there is no "and", "not" or "or" anywhere in it). I think you may be confusing 'logic 'and language and they are not the same thing(or did you mean to say something else?)
apeiron
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#59
Nov29-11, 06:00 PM
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Quote Quote by disregardthat View Post
I don't mean that, say, inductive reasoning is wrong, but I do mean that it is not logical.
I too have not been able to understand the grounds of your objections. Can you provide references in case you are expressing a particular school of thought here?

It seems now you are constrasting induction with deduction.

But just talking about deduction is too narrow a definition of "logic" to answer the OP, which is about how logic arose in human history - was it more found or invented?

At its broadest, saying things are logical is saying they are orderly and with pattern. The world seems to operate a certain way, and our minds are shaped to appreciate that - either by evolution, or learning, or most likely a combination/refinement of both.

Induction does seem to be the main way that brains naturally learn - generalisation from experience. Bayseian inference.

Deduction does seem to be a new level of thinking that depends on the human ability to handle syntactic structure. And so logic in this sense piggyback's on a capacity for grammar and would be exclusively human.

So there may be no essential dispute here, just a difference of terminology. You want to have a tight definition of logic, and I take a much looser one (because I'm more interested in the general issues rather than the specific applications).
RegressLess
#60
Nov29-11, 06:59 PM
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It's difficult to understand how one can have a logical thought without language since our thoughts are comprised of words, but language had to start somewhere and it is absurd to think it would come from minds incapable of logic. Without the ability to reason, language is pointless. That was the reason I mentioned animals capable of rational thought. They do it without language.
apeiron
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#61
Nov29-11, 07:32 PM
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Quote Quote by RegressLess View Post
Without the ability to reason, language is pointless. That was the reason I mentioned animals capable of rational thought. They do it without language.
I have a whole bookcase of books that debate just this one issue.

My own view in fact is that what we call reason followed our invention of language. Which is why I just said there is a broad truth in the idea that while animals are capable of induction, only humans employ deductive reasoing.

Though yes, animals are capable of limited reasoning - when placed in the kind of experimental set-up that demands this of them, and so essentially scaffolds their mental response in the same way that language continually scaffolds our own thinking.

And as I say, there is a huge literature that argues this both ways. So regardless of which side you want to argue, there is plenty of source material to call upon.
RegressLess
#62
Nov29-11, 07:44 PM
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Quote Quote by apeiron View Post
when placed in the kind of experimental set-up that demands this of them
Orangutans and chimps have been known to hunt with spears. Crows attract large predators in the direction of prey so that they can get the leftovers. All of these animals have learned the benefit of tribalism. These are all examples of reason in natural environments, not some experimental set-up.
apeiron
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#63
Nov29-11, 07:55 PM
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Quote Quote by RegressLess View Post
Orangutans and chimps have been known to hunt with spears. Crows attract large predators in the direction of prey so that they can get the leftovers. All of these animals have learned the benefit of tribalism. These are all examples of reason in natural environments, not some experimental set-up.
But is this displaying inductive reasoning or deductive reasoning?

As a Peircean, I would also want to bring in abductive reasoning here - the kind of creative leaps of the imagination which do seem part of our naturally evolved cognition, which means that even animals have more than inductive reasoning, even if they still have less than deductive reasoning.

So yes, I know of the evidence for animals being smart, being co-operative. But that is precisely why it demands great care to account for how humans are actually different.
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#64
Nov29-11, 08:11 PM
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Quote Quote by apeiron View Post
But is this displaying inductive reasoning or deductive reasoning?

As a Peircean, I would also want to bring in abductive reasoning here - the kind of creative leaps of the imagination which do seem part of our naturally evolved cognition, which means that even animals have more than inductive reasoning, even if they still have less than deductive reasoning.

So yes, I know of the evidence for animals being smart, being co-operative. But that is precisely why it demands great care to account for how humans are actually different.
I don't know how we could tell by which means they come up with these rational concepts. I'd love to see some research on that. However, I'm fairly convinced that the human ego is the only significant difference between us and the rest of the great apes.
apeiron
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#65
Nov29-11, 08:48 PM
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Quote Quote by RegressLess View Post
Orangutans and chimps have been known to hunt with spears.
I agree this is a cool fact ...



But also, it is credited to mimicry - so inductive rather than deductive reasoning really. Even if it is still a remarkable thing.

...our long-armed cousins do indeed show a remarkable ability to mimic our behaviour.
This individual had seen locals fishing with spears on the Gohong River.
Although the method required too much skill for him to master, he was later able to improvise by using the pole to catch fish already trapped in the locals' fishing lines
.

http://www.dailymail.co.uk/sciencete...#ixzz1f9YUfgDX
RegressLess
#66
Nov29-11, 08:56 PM
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Quote Quote by apeiron View Post
But also, it is credited to mimicry - so inductive rather than deductive reasoning really. Even if it is still a remarkable thing.
Well, you got me there, but what about this: Chimps spearing bush babies
apeiron
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#67
Nov29-11, 09:30 PM
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Quote Quote by RegressLess View Post
Well, you got me there, but what about this: Chimps spearing bush babies
Again, that is impressive, but inductive. It is a natural extension of an existing behaviour. Poking and smashing are ways to make things happen. Grabbing a rock or a stick are easy habits to learn from experience and observation.

But note that crediting animals with powers of inference is actually something here. For a long time, the null hypothesis championed by the Behaviourists was that learning was purely associative.

So the claim was that animals essentially did random things and accidentally discovered the way to make things happen through reinforcement feedback. The world shaped up their behaviour to look clever. But there was no "leap of insight" - despite what the rival Gestalt school of psychology was arguing at the time, based on its own observations of primate problem solving.

So yes, the modern view is now much more willing to grant animals the ability for sudden insight - to be able to think this kind of thing has worked in the past and could be applied right now to achieve my goal.

Yet then there is the lack of syntax, and consequently a lack of "strong deduction" in animal reasoning. So there are the similarities, but also the critical differences.

A grammar-handling brain is able to do something different. All higher animals could be said to reason, to be in some way logical thinkers. But it comes in flashes of intuition and goal-oriented experimentation. It is not structured and guided by conscious abstractions.
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#68
Nov29-11, 09:49 PM
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Quote Quote by apeiron View Post
So the claim was that animals essentially did random things and accidentally discovered the way to make things happen through reinforcement feedback. The world shaped up their behaviour to look clever. But there was no "leap of insight" - despite what the rival Gestalt school of psychology was arguing at the time, based on its own observations of primate problem solving.
Quote Quote by apeiron View Post
Poking and smashing are ways to make things happen. Grabbing a rock or a stick are easy habits to learn from experience and observation.
These two ideas sound similar...

If their minds work in such a different way, how do you explain Koko, the gorilla who speaks with sign language? Sure, it's an extraordinary circumstance, being that she interacts with humans daily, but could the type of mind you ascribe to these "lesser" creatures do that?
apeiron
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#69
Nov29-11, 10:01 PM
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Quote Quote by RegressLess View Post
These two ideas sound similar...

If their minds work in such a different way, how do you explain Koko, the gorilla who speaks with sign language? Sure, it's an extraordinary circumstance, being that she interacts with humans daily, but could the type of mind you ascribe to these "lesser" creatures do that?
Koko and all similar experiments have demonstrated that animals in fact can't master generative syntax. You have to be prepared to consider here both what they can do, and what they can't.
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#70
Nov29-11, 10:51 PM
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No comment on the "these two sound similar" part?
disregardthat
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#71
Nov30-11, 07:57 AM
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Quote Quote by Maui View Post
No way. Logic is also a part of reality to which you compare to find out if your reasing is faulty or valid. It's reality that decides what reasoning is valid
I said that inductive reasoning is not logical reasoning. I can hardly believe anyone would say otherwise. In what sense is: "I have only seen green leaves", hence "leaves are green" a logical argument? It is not, and it is non-sense. It is not a logical argument and a logical conclusion, but a whole new game with different rules and different applications.



Take a logical argument, you will never find any reason to verify it. Rather, the meaning we give propositions confine themselves to logical laws (we force them to), and in such a way logic must be valid reasoning.
Maui
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#72
Nov30-11, 09:11 AM
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Quote Quote by disregardthat View Post
I said that inductive reasoning is not logical reasoning. I can hardly believe anyone would say otherwise. In what sense is: "I have only seen green leaves", hence "leaves are green" a logical argument? It is not, and it is non-sense. It is not a logical argument and a logical conclusion, but a whole new game with different rules and different applications.



Take a logical argument, you will never find any reason to verify it. Rather, the meaning we give propositions confine themselves to logical laws (we force them to), and in such a way logic must be valid reasoning.


Well yes, as soon as i put on my philosophy shoes your point seems clearer to me. In a certain sense, the base of knowledge is philosophy(recently there was a thread in the General forum about it and nobody is disputing that).

But what i was objecting to was your perceived and implied stance that language and logic were one and the same(maybe i got this part wrong?)


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