I am of the understanding that Logic is universal, just not universally adhered to. The only truth associated with Logic involved whether or not an argument can have a truth value associated with it due to conjunctions, disjunctions, etc. Ultimately, for the layman, Logic only need apply at the surface level.

http://www.scribd.com/doc/7535202/warrantless-selfevidence-antifoundationalist-stance-on-logic

http://www.as.miami.edu/personal/sevnine/Evnine-Universality%20of%20Logic.pdf

I disagree - logic needs only the fact that certain questions can be answered with either "yes" or "no" and that there is no question which can be answered by "yes" and "no" at the same time.

This has nothing to do with formalisms or systems, but with the capabilities of human brains.

So, you are saying that logic is universal on one level, but if you go up than it is not universal anymore? - How is that possible, at which level does logic start to become non-universal and how do you recognise when it fails to be universal?

I think you mix up logic with assumptions and axioms - these you have to make, because of the universality of logic. Let me give a very trivial example:

You see that the street is wet and you conclude that it has rained. But this is not necessarely true: the street might also be wet, because it got wiped by the street cleaning.

In order to get a logical conclusion you have to make at least one additional assumption: The street is wet, so it was raining - provided that the street was not wiped by the street cleaning.

Logic can be applied anywhere, in that sense it is universal ! It is a play of thoughts which deduce the mechanism of an event or a theory. Although there are some, which have no logic, whatsoever !

True, logic always may not be true ! It is a sequential thought process of an individual, which depends on many external factors and hence changes from person to person! It is a subjective deduction which may be right for one, wrong for another !

I am of the understanding that Logic is universal, just not universally adhered to. The only truth associated with Logic involved whether or not an argument can have a truth value associated with it due to conjunctions, disjunctions, etc. Ultimately, for the layman, Logic only need apply at the surface level.

Placed in the context of the universe, or everything, there is nothing, including logic as well as the illogical, in the mind that is not also universal, as the mind itself necessarily derives from this benchmark, the universe. Placed in any other context other than the universe, in other words contextualized, logic and everything else contextualized will no longer be necessarily universal, yet may be thereby easily deemed to be illogical if the contextualized logic is then illogically (fallaciously) equivocated as universal, true everywhere.

A proposed working definition for logic therefore could be: Logic is rational thinking consistent with both a physical and symbolic universe. By rational I mean in proportion to the universe.

Follow up: so if this is the working definition, we are assuming the existence of such universally consistent logic... Now, does an absolute logic exists? Can we make a logical system out of this definition which is not just consistent but also complete?

As of me beginner logic is an art of deriving solution

Eg :

I need to derive it by addition

ans : 10

5+5= 10

3+5= 10

2+2+2+2+2 = 10

10 + 0 = 10

Based on the input and weight of that input Logic may vary

But logic of handling those symbol may standard up to some extend

This is my logic of conveying answer .... :)

Thank you..

While we rely on the Boolean valued system, it is not the only derived system of logic. One can also pose logical problems in terms of Łukasiewicz logic which is a three valued logic. There are other systems of multi-valued logic as well.

I would clarify what is the meaning of universality under this context.

Dear Vijaykumar S: Logic does not vary just because you get sometimes the same answer to different Problems.

The fact that 5 + 5 = 7 + 3 = 2 + 2 + 2 + 2 + 2 = 10 + 0 = 10 is NOT based on a varying logic (the Logical Operation "+" here is in fact allways the same and used in the same way) while the same result for each operation is the consequence of an inherent property of the set of integer numbers and the relation "+" which means that you will get the same answers by default due the axiomatic system of this kind of mathematical set.

Dear Sven Hanfstängl: Could you elaborate what you mean by logic is not allways true. In fact it has to be allways true, if your axioms and assumptions are correct. It holds here, however, the principle "ex falso sequitur quod libet" which means that from one false presumption you can deduce whatever you want, but that does not falsify logic.

I think, any area of Mathematics, philosophy, biology, etc ... that has its roots in the NATURE will be universal. I am an electronics guy, so, I hope that, I understood your question correctly: I am referring to LOGIC in the electronics sense. TRUE, FALSE, and the logical operations, AND, OR, NOT, and may be even the little-less-intuitive one : XOR. (and the variants NAND, NOR).

If you look at the theoreticians that worked on the theory of LOGIC, first of all, they are from pretty much every country you can imagine, and from MATHEMATICS, ELECTRONICS, almost all ENGINEERING disciplines.

So, if I understood your question correctly, IS THE LOGIC UNUVERSAL, which means, independent of the cultures etc ... definitely YES.

If the question is : IS IT DISCIPLINE-AGNOSTIC ? i.e., it is as common in biology as it is in engineering, I would say NO. One interesting area is Genetics, where you have a four-valued intricate mathematical system that contains the secret of life ! Computational Biology is about as close as medicine gets to the LOGIC I am describing. And , YES, it is completely universal. Because, it has its roots in the NATURE.

Tolga 4 valued means ? AGCT?

yes. definitely. Sorry, I should have put it there

But place by place and it's situation it too brings various meaning

logical symbols same but bring different meaning

so my friend is this logic represent symbols ?

you are talking about the --- underlying theory vs. --- abstraction.

you can transport the underlying theory to any domain you want, by applying the appropriate MAPPING. For example , the AND, OR operations I describe in electronics (THEORY), can be mapped to describing certain symbols in ancient scripts as long as the correct one-on-one transformation (MAPPING) can be found.

An example is, Julius Ceasar described a message hiding scheme that adds 3 to each letter to hide the message. Now, we can MAP it to MODULO 3 ADDITION. Similar mappings can be done in LOGIC.

Logic is akin to truth on the subject and thus appeals to most minds - except biased ones looking for selfish fulfilments.