Logic: wuzzit and howzzit?

[Radiantshadow]

Or, for those unskilled in Gibberish, what is logic and how do we know whether something is logical?

 

[Tin Man]

That's a loaded question. I don't think I could answer it in less than twenty-five thousand words. Since I don't have the time or interest required, I'll just say something mysterious and ambiguous.

Logic is both the knife and the one who wields it.

 

[Korg]

The scope of this question literally spans thousands of years and millions of writings by individuals dating back to ancient Greece. Needless to say, I don't have time to cover it all before lunch.

That said, I'd like to point out that contrary to some false ideas, logic is not the study of truth. It's the study of the methods used to arrive at the truth.

 

[tfg345i4u5lw]

I'll try.

Logic: taking a collection of agreed upon principles and facts and arranging them in a way that allows you to arrive to a newly agreed upon principle or fact.

 

[hk427f3]

It would be good to narrow the scope of this discussion, and state what your purposes for it are.

By nature humans are endowed with powers of reasoning. Logic is the study of the uses of those powers.

Is what Introduction to Logic said.

 

[Matt3737]

What Korg and Meer said is correct. Reasoning is an individual's processing of information, whereas logic is the study of reasoning. This aspect is like a self-similar recursive function in that it can be restated as reasoning about reasoning (resembling Jacobi's analogy).

 

[Radiantshadow]

Thank you all for the responses. As you can likely tell, I'm a complete noob at philosophy. Whip out the gag and pyre if my queries become moronic.

The scope of this question literally spans thousands of years and millions of writings by individuals dating back to ancient Greece. Needless to say, I don't have time to cover it all before lunch.

That said, I'd like to point out that contrary to some false ideas, logic is not the study of truth. It's the study of the methods used to arrive at the truth.

Agreed on the second point. What I am curious about, and phrased badly, are the criteria with which one studies methodologies. Must they be internally consistent? Verifiable? Observable? Transparent to all or only a few? Must they be able to be proven wrong, or only right? Can a system ever be completely consistent without drawing on others or taking some things for granted? Etc.

Methods require steps; jumping from start to finish makes bad product. While being completely free of logical fallacy strikes me as impossible, I would like to dodge as many as possible.

I'll try.

Logic: taking a collection of agreed upon principles and facts and arranging them in a way that allows you to arrive to a newly agreed upon principle or fact.

How are these principles agreed upon? What are the criteria used/steps taken to verify accuracy in the first place?

It would be good to narrow the scope of this discussion, and state what your purposes for it are.

By nature humans are endowed with powers of reasoning. Logic is the study of the uses of those powers.

Is what Introduction to Logic said.

I wish to improve my reasoning abilities; learning the language in order to break apart and individually study my reasoning processes and assumptions seemed like a good first step. Honing Ti, if you will. Does this belong in the realm of logic?

Zooming-in: What characteristics are used to separate what is logical from what is not? More simply, how does one prove a set of statements?

What Korg and Meer said is correct. Reasoning is an individual's processing of information, whereas logic is the study of reasoning. This aspect is like a self-similar recursive function in that it can be restated as reasoning about reasoning (resembling Jacobi's analogy).

{Meta-cognition of a sort?}

If something begins and ends with itself, how do you verify it to form accurate statements? Need we do so to be logical {which I take to mean 'error-free reasoning', the verification of which being the root of my curiosity}?

{I get the feeling my empiricist training is going to bleed into this discussion. Apologies in advance.}

 

[Matt3737]

Proof means to make resistant to change, i.e. like water-proofing. Logic, like mathematics, is about recognizing patterns and establishing interwoven lines of reasoning. Text and textiles come from the same root word. If you understand how a kevlar vest (bullet-proof vest) is able to stop the puncture of a bullet then you metaphorically understand how logic operates.

 

[hk427f3]

More simply, how does one prove a set of statements?

Absolute proof is hard to come by. But, you can evaluate the strength or validity of an argument. In the real world, it's messy and complicated, because the logical form of the argument must be valid as well as any facts that are asserted. People study formal logic in order to look at the shapes of these arguments without having to worry about all of the complications that come from the real world and language and everything else. Also, the conclusion of an invalid argument isn't necessarily false, it's just that the method of arriving at the conclusion is flawed.

For example:

Obesity causes diabetes. Bob is obese. Therefore, Bob will become diabetic.

The form of this argument (if P then Q, A is P, therefore A is Q) is valid, but the argument in the real world is not, because obesity doesn't absolutely cause diabetes.

I'm just swinging here, hopefully this is helpful.

 

[Korg]

Agreed on the second point. What I am curious about, and phrased badly, are the criteria with which one studies methodologies. Must they be internally consistent? Verifiable? Observable? Transparent to all or only a few? Must they be able to be proven wrong, or only right? Can a system ever be completely consistent without drawing on others or taking some things for granted? Etc.

Methods require steps; jumping from start to finish makes bad product. While being completely free of logical fallacy strikes me as impossible, I would like to dodge as many as possible.

Rather than answering these questions which would require quibbling and nit-picking your word choices to death (nothing personal), it's going to be easier to redirect you towards a decent introduction to logic so you can grasp the basics.

This seems like an okay place to begin.

Also:

A very easy to understand PDF that lists a number of logical fallacies with examples.

 

[the]

Logic is the carrot someone holds just out of the reach of the ass.

 

[Radiantshadow]

Proof means to make resistant to change, i.e. like water-proofing. Logic, like mathematics, is about recognizing patterns and establishing interwoven lines of reasoning. Text and textiles come from the same root word. If you understand how a kevlar vest (bullet-proof vest) is able to stop the puncture of a bullet then you metaphorically understand how logic operates.

Ok: to proof is to make constant. What rules govern this process?

{Edit: Nevermind, answered below.}

Bouncing to Meer...

Absolute proof is hard to come by. But, you can evaluate the strength or validity of an argument. In the real world, it's messy and complicated, because the logical form of the argument must be valid as well as any facts that are asserted. People study formal logic in order to look at the shapes of these arguments without having to worry about all of the complications that come from the real world and language and everything else. Also, the conclusion of an invalid argument isn't necessarily false, it's just that the method of arriving at the conclusion is flawed.

For example:

Obesity causes diabetes. Bob is obese. Therefore, Bob will become diabetic.

The form of this argument (if P then Q, A is P, therefore A is Q) is valid, but the argument in the real world is not, because obesity doesn't absolutely cause diabetes.

I'm just swinging here, hopefully this is helpful.

This is along the lines of what I was looking for, thank you. I wasn't aware there were argumentative forms, only facts to support or discredit theories*. If the process is messy, to what can it be realistically applied?

{*One thing that comes to mind is scientific theory. In psychology, there are many theories that attempt to explain behavior and cannot be proven false, yet may nonetheless be predictive. If a theory cannot be falsified, does it conform to the scientific method? Must it in order to be truthful and useful, as in the case of, say, various therapeutic programs?}

Rather than answering these questions, which would require quibbling and nit-picking your word choices to death (nothing personal), it's going to be easier to redirect you towards a decent introduction to logic so you can grasp the basics.

This seems like an okay place to begin.

Also:

A very easy to understand PDF that lists a number of logical fallacies with examples.

The questions were rhetorical, reflecting a desire to understand mechanics. Your links, therefore, are greatly appreciated.

Logic is the carrot someone holds just out of the reach of the ass.

Heh, all the world's a stage, each has a part, or several, to play. Understanding limitations is a good humility-check.

 

[Matt3737]

Ok: to proof is to make constant. What rules govern this process?

This is along the lines of what I was looking for, thank you. I wasn't aware there were argumentative forms, only facts to support or discredit theories*. If the process is messy, to what can it be realistically applied?

{*One thing that comes to mind is scientific theory. In psychology, there are many theories that attempt to explain behavior and cannot be proven false, yet may nonetheless be predictive. If a theory cannot be falsified, does it conform to the scientific method? Must it in order to be truthful and useful, as in the case of, say, various therapeutic programs?}

The rules themselves are generally premises or axioms that are self-evident truths, just as reasoning begins with premises so does the meta-reasoning of logic have foundational principles that cannot be indepedently verified, but appear to be self-evident.

In the same self-similar manner that logic operates, i.e. reasoning about reasoning, so too are scientific theories on a broad level a part of circular reasoning.

"using the scientific method to judge the scientific method is circular reasoning"

An individual theory is considered valid by facts that support such an interpretation. A theory has validity because while being established as not being irrefutably true (it is potentially falsifiable), if we have yet to present such evidence then we can be fairly certain of it's soundness. Not all theories are falsifiable, as you stated, but can be supported in an indirect manner like utility. If it works, then it works regardless of how true it may be.

Popper stressed that unfalsifiable statements are important in science. Contrary to intuition, unfalsifiable statements can be embedded in - and deductively entailed by - falsifiable theories. For example, while "all men are mortal" is unfalsifiable, it is a logical consequence of the falsifiable theory that "every man dies before he reaches the age of 150 years". Similarly, the ancient metaphysical and unfalsifiable idea of the existence of atoms has led to corresponding falsifiable modern theories. Popper invented the notion of metaphysical research programs to name such unfalsifiable ideas.

Following lines of reasoning is about minimizing doubt and insecurity while furthering our breadth of knowledge. We can be assured by the collective lines of reasoning that limit and minimize logical incoherence in the same manner that we calculate the area of a curved space, i.e. calculus.

In everyday life, we measure distance using straight lines of a consistent spacing. A graph is like a weave on a loom; an x and y plane is to the warp and weft. Area then is to collate the measure of a well-defined space. Unlike mathematics though, life is not always so well-defined. Can a straight line even exist if the universe is fundamentally a curved space? To calculate the area of a circle, we implement a creative solution that minimizes the amount of irrational space. Because a curved line cannot be measured using a straight line, we break the straight line down into infinitely smaller sections that can better approximate a curved line.

 

[sprinkles]

Axiomatic relationship between propositions.

 

[Quintessence]

The manner in which a mind articulates meaning from a beginning set of conditions into a final set of results according to the nature of that mind and the goals of its development is "logic". It is non-representational unless a special language is developed to symbolize that "manner of articulation" or unfolding of the meaning in that mind. The language is never able to "catch up" to the semantic reality, and if there is falsification ANYWHERE in the system which preceded the language then the logic of the mind can never be fully articulated at all, to say nothing of formally and symbolically represented.

Therefore in a sense EVERYTHING is logical, since it always has a "logos" or system of developmental vectors which unfold a potential into actuality. All notions of causation, including "mental" ones like the sense of propriety in formal systems which appear as "axiomatic relations between propositions", such as validity, soundness, cogency, and so on, are all secondary and dependent upon a reality they can never properly represent as long as "falsehood" is possible. Therefore logic as we know it in this realm is inherently falsified but inherently inarticulable as falsified. It is not complete nor is it consistent, but this can never be demonstrated within its own constraints of representation. This contradicts a greater reality with a logos that will overbear and annihilate the logos of this falsified pseudo-reality .

The accurate META-logic which describes this war between two logoi is not comprehensible to a mind which was fully designed and programmed within this narrow cosmic scheme, and it can also never fully integrate itself into this false realm without destroying itself. If it properly "argues against" this reality by its way of being, it will attune itself to a logic which does not resonate to this realm and yet is the only lifeline it has to a logos which properly can nourish it and eventually extract it from this realm. Without an appropriate lifeline in place which enables this transition, then attempting to rescue that mind will be just as damaging, perhaps MORE damaging than allowing it to persist in a realm that is illusory to its proper nature.

Attached to such beings there is a false mind which accepts the logos of this realm and can only operate with logic which does not fundamentally contradict this realm. This doesn't mean that it operates in the realm of symbolic logic such as is studied and rarefied in universities, it only means that it unfolds its processes of development according to strict adherence to the laws of the mind which organizes this apparent but false reality. Only by meditation can certain qualia manifest to a mind which is besot with such a false mind, which is called "ego", and thereby behold contents of a reality which will be forever unknown and unintelligible to said ego. Logical operations of thought which growingly take into account this True Reality are all that can nourish meaning within such mind, which otherwise slowly shrivels and dies incarnation after incarnation. Once a critical mass of viability is achieved, such a mind is transplanted from here to a realm where such a process can be continued far more efficiently.

Until then many suffer under the delusion that logic is what textbooks say it is.

 

[Barnabas]

Logic

 

[LucyJr]

One other think along many other points stated here:
-logic can't verify the validity of a pretention of truth
-logic can verify if something is not consistent, if a proposition is false, if some propositions are internally contradictory;
-the nature of logic is not provable, rather we use it and trust in in on a intuitive base; it's the same with morallity, and other "basic stuffs";

Edit:
"logic can't verify the validity of a pretention of truth"- meaning

-logic can't verify the truthiness of a pretention of truth

 

[sprinkles]

One other think along many other points stated here:
-logic can't verify the validity of a pretention of truth
-logic can verify if something is not consistent, if a proposition is false, if some propositions are internally contradictory;
-the nature of logic is not provable, rather we use it and trust in in on a intuitive base; it's the same with morallity, and other "basic stuffs";

Logic verifies validity. What it doesn't verify is truthiness. These are different things and the difference is important.

For example with a carry adder, MOSFETs or BJTs or whatever are arranged by logic into a gate which works on a truth table.
If the input is 0 0, it directs output to a pin representing 0.
If the input is 0 1, it directs output to a pin representing 1.
If the input is 1 0, it also directs output to a pin representing 1.
If the input is 1 1, it directs output to the carry pin, which either leads to a carry indicator on the display, or into the carry-in pin of another adder.
You can stack these up in a ripple configuration and build a calculator.

Basically if you put the right stuff in and the formula is valid, you get a valid answer. If you put the right stuff in. The formula isn't always valid though, but when it is, the truth of the output depends solely on the truth of the input, just like doing addition on your calculator. If you get an answer which is not true (is wrong) it is most likely because it was you that put in the wrong input.

 

[LucyJr]

Logic verifies validity. What it doesn't verify is truthiness. These are different things and the difference is important.

Yes, I think I used the wrong word, although the idea was clear in my head. When I said "logic can't verify the validity of a pretention of truth" I was actually saying that logic can't verify if a pretention of truth is actually true. But your right, the wording is kind of ambiguous. Thanks for clarifying

 

[sprinkles]

Yes, I think I used the wrong word, although the idea was clear in my head. When I said "logic can't verify the validity of a pretention of truth" I was actually saying that logic can't verify if a pretention of truth is actually true. But your right, the wording is kind of ambiguous. Thanks for clarifying

Yup.

So for example if you have:
All fots are blue
Nagle is a fot
Therefore Nagle is blue

With this you have a valid formula. It's self evident based on axioms about quantifiers, specifically in this case the word "all". If something is a fot, it must be blue. We don't have to explain why, it rests within the fundamental nature of the concept of "all fots are" If there's a fot which isn't blue then you have a contradiction, but that's not a problem with the logic, that's a problem with putting false premises into the logic.

If not all fots are blue, the logic is still valid! It's just not sound.