Logic is Absolute

[jedaisoul]

In the thread "The Physics of God" I commented:

If the big bang theory is correct then time itself started with the big bang. Therefore the universe has existed "for all of time" even though it had a beginning. Also there was no time or place in which your putative creator existed...

Later, questor said:

You may think it is a logical fallacy, but we still don't know what happened or why. Arguing from what humans call ''logic'' does not answer all questions. The Big Bang does not strike me as a logical event. You seem to be arguing that the universe just ''happened''' for no reason and with no cause. That does not seem ''logical'' to me. I'm sure this argument has been hashed out many times over. The true answer is... we don't know what happened, how or why.

Putting aside the issue of the big bang itself, this attitude to logic as being "human" appears to be a common misconception. So I felt that it deserved a separate thread...

 

I would suggest that logic is absolute. If your axioms are correct and you apply a logical process, then your conclusions must be correct. On the other hand, if you arrive at a demonstrably false conclusion, either one (or more) of your axioms must be false, or you applied an illogical process (or both). This goes beyond human judgement, it is absolutely true in all circumstances because that is how we define logic.

 

Note: It is a possible that the answer to whether something is logical or not is "don't know". So this does not mean that we always know whether a process is logical or illogical, but logic is a process and can never be illogical, and vice versa. Therefore logic is not merely "human", it is universal.

 

However, there is a use of the word "logic" which is very human: "fuzzy logic". Fuzzy logic is the ability to come to a conclusion based on insufficient information. In most real life situations we do not have full information on the causes and likely outcome of a decision, so almost all decisions are made using "fuzzy logic". But that is, in fact, an inappropriate use of the word "logic". I would suggest that it should be called "fuzzy illogic", as it is fundamentally illogical. Somehow I can't see that catching on :phones:

 

Another interesting point is that, although I maintain that logic is absolute (therefore something cannot be "relatively logical"), the opposite, illogic, is a relative term. So if a process of deduction involves ten steps that are logical and only one that is illogical, is it less illogical that one which involves ten steps that are illogical and only one that is logical? What do you think?

[C1ay]

I would suggest that logic is absolute. If your axioms are correct and you apply a logical process, then your conclusions must be correct.

 

You must first have sufficient data to apply a logical process else logic will fail. Logic is a process with dependencies and it is only absolute when those dependencies are satisfied with valid values.

[jedaisoul]

You must first have sufficient data to apply a logical process else logic will fail. Logic is a process with dependencies and it is only absolute when those dependencies are satisfied with valid values.

I agree whole heartedly, except for the words "else logic will fail". I suggest that the "process of deduction" will fail, but that does not mean that logic (as part of that process) fails. It's a small point, but I think it is valid.

[questor]

I do not think logic is absolute. mathematics is absolute because regardless of who performs it, the answer is the same and proveable. The DEFINITION of logic could be absolute as long as everyone agrees upon it. When two human beings view an event, think about a non math solution, and come up with two opposing views, one of the two is not logical. An example would be two politicians, one wants to raise taxes to pay off the national debt. The other wants to lower taxes to give the consumer more money to spend and allow more money to form small businesses, which increases tax revenue. Which one is logical?

Another example may be welfare. The problem is poor people. One wants to give them money to live on, the other wants them to work to earn their own money as long as they are able. Which is logical?

math does not allow the influence of the human mind, morality, idealism, or other human trait. Math is immutable. How do you find logic when two people view the same event and cannot agree on a solution? Logic is absolute only when each factor in the development of the conclusion is true.

[jedaisoul]

I do not think logic is absolute. mathematics is absolute because regardless of who performs it, the answer is the same and proveable. The DEFINITION of logic could be absolute as long as everyone agrees upon it. When two human beings view an event, think about a non math solution, and come up with two opposing views, one of the two is not logical.

I think it goes further than the definition, but that is key. I define a process of deduction as being the application of logic to the assumptions you have made. So the overall process of deduction may be flawed by incorrect assumptions, but the logic is valid, because if the "logic" is invalid, it's not logic, it's illogic. So logic is absolute.

 

If, on the other hand, you define logic as the whole process of deduction, then, yes, it is only as correct as the assumptions you make. It is not absolute. So whether logic is absolute or not hinges on how you define it.

 

I think it is more useful to define it the way that I do. However, in your examples, there is a further issue. Decisions are being made for which it is impossible to know the validity of the assumptions. Therefore both decisions are guesses. They are not based on logic, but rather on "fuzzy logic".

[Turtle]

..

However, there is a use of the word "logic" which is very human: "fuzzy logic". Fuzzy logic is the ability to come to a conclusion based on insufficient information. ...

 

I don't find that an accurate description of fuzzy logic, and the use of any word(s) is strictly human as far as we yet know so the differentiation you make is logically flawed. :eek: :D

 

... Fuzzy logic allows for set membership values to range (inclusively) between 0 and 1, and in its linguistic form, imprecise concepts like "slightly", "quite" and "very". Specifically, it allows partial membership in a set. ...

Fuzzy logic - Wikipedia, the free encyclopedia

 

There is a more lengthy description on the page dealing with the 'fullness' of glasses of water, but whether classical predicate logic is used or fuzzy logic to describe the condition, both have equal access to the same information, i.e. the glass with water. ;) ;)

[jedaisoul]

I don't find that an accurate description of fuzzy logic

I stand corrected, and thank you for that. I was using the term "fuzzy logic" incorrectly to meant "imprecise logic".

 

and the use of any word(s) is strictly human as far as we yet know so the differentiation you make is logically flawed.

I agree that others will not immediatly agree with the statement, because they are using a different deinition of "logic". However, once the definition I use is understood, the distinction is valid.

[Turtle]

I agree that others will not immediatly agree with the statement, because they are using a different deinition of "logic". However, once the definition I use is understood, the distinction is valid.

 

Kinda' a de-fuzzification of the term 'absolute' I imagine. ;) Sounds perfectly logical to me. ;)

[jedaisoul]

Kinda' a de-fuzzification of the term 'absolute' I imagine. :edevil: Sounds perfectly logical to me.

A good way of describing it.