An introduction to formal logic

a_unique_person

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After looking at the mathematical represention of Franko's arguments in the thread about fallacy of combination, is there anywhere to find a nice introduction to this, or can anyone put down the basics in this thread?
 
COMPOSITION

Description: An argument in which one assumes that a whole has a property solely because its various parts have that property. Composition is a type of Fallacy of Ambiguity.

That's basically the whole of it. C is a letter. A is a letter. T is a letter.

CAT is not a letter.


While it is possible to arrive at a conclusion which is broadly correct, it is still a fallacy to arrive at the conclusion due to assuming it's property.

For instance:

Cats are animals.
Kittens are animals.
A litter of kittens are animals.

Edit-

Just run a google search if you want a comprehensive list of most (if not all) the formally recognized logical fallacies (there are around 40 that most debate sets recognize, some way more common than others)

http://www.locksley.com/6696/logic.htm is one that I sometimes look to when I need to refresh myself.
 
Forget the syllogism ...

Just any one of you A-Theists (just one) disobey the Laws of Physics.

If you are claiming that you do NOT obey the Laws of Physics, then kinding demonstrate this -- what is so hard to understand?

Are you claiming that You are NOT made of atoms?

Are you claiming that Atoms do NOT obey the Laws of Physics

Are you claiming that YOU CAN DIOBEY THE LAWS OF PHYSICS???

OKAY!!! I hear you! Just do IT ... and shut me up once and for all!

What is with you nutty A-Theists?

you agree premise #1 is true, you agree premise #2 is true, you cannot diprove the conclusion; but the syllogism is flawed, and Franko is the one who doesn't understand Logic?

... yeah ... keep telling yourself that. While you are at it ... Tell yourself that I am really the insane one of us, also. That will help ... at least until you cease to exist ...
 
Oh, I think I should maybe put a real world example forth:

Here is an example of why the Fallacy of Composition is a fallacy:

Sodium is a deadly poison.
Chlorine is a deadly poison.
Salt then, is a deadly poison.

It's a flawed construct with a conclusion that is obviously, and verifiably false. Salt is absolutely necessary to maintain human life (and in fact most life on earth), but it's component elements are two things that can destroy life.
 
Fade is that your demonstration of you disobeying TLOP?

Why can't you seem to address the actual points?

What is stopping you Fade?
 
Fade said:


That's basically the whole of it. C is a letter. A is a letter. T is a letter.

CAT is not a letter.


While it is possible to arrive at a conclusion which is broadly correct, it is still a fallacy to arrive at the conclusion due to assuming it's property.

For instance:

Cats are animals.
Kittens are animals.
A litter of kittens are animals.

Edit-

Just run a google search if you want a comprehensive list of most (if not all) the formally recognized logical fallacies (there are around 40 that most debate sets recognize, some way more common than others)

http://www.locksley.com/6696/logic.htm is one that I sometimes look to when I need to refresh myself.

I have found plenty of the sites that have the logical fallacies, but I want to find out what it is rather than what it is not.
 
Are you claiming that You are NOT made of atoms?

Are you claiming that Atoms do NOT obey the Laws of Physics

Are you claiming that YOU CAN DISOBEY THE LAWS OF PHYSICS???

OKAY!!! I hear you! Just do IT ... and shut me up once and for all!

What is with you nutty A-Theists?

Put up or shut up!
 
Excellent example

Excellent example Fade. :)

Fade said:
Oh, I think I should maybe put a real world example forth:

Here is an example of why the Fallacy of Composition is a fallacy:

Sodium is a deadly poison.
Chlorine is a deadly poison.
Salt then, is a deadly poison.

It's a flawed construct with a conclusion that is obviously, and verifiably false. Salt is absolutely necessary to maintain human life (and in fact most life on earth), but it's component elements are two things that can destroy life.
 
From your own statements, Franko:

1. Atoms obey TLOP (or, A is less than T)

Agreed, no one argues this.

2. You are made of atoms (or, Y=A)

Here, we have a problem. While the statement is correct, the mathematical representation does not reflect the statement, and this is why it becomes a fallacy of composition. Y=A would mean you ARE an atom, not you are made of atoms. The correct mathematical representation, then, is Y>A.

3. You obey TLOP (or, Y is less than T)

Now, this conclusion is true, but not for the reasons your syllogism states. No one is claiming we do not obey the laws of physics (or, more correctly, that we are not constrained by the laws of physics). What people are trying to tell you is that your logic does not support this:

1. A is less than T
2. Y>A
3. Y is less than T

Statements 1 and 2 do not lead to 3.

A more correct syllogy would be:

1. You obey the laws of physics
2. The laws of physics are determinisitic.
3. You are deterministic.

Now, that would correct the logical fallacy; however, now you have the burden of proving that the laws of physics are indeed determinisitic, a matter that has not been settled in a long time, and which centers on certain debates about the various uncertainty principles.

Franko, your logic was flawed, even if the conclusion was valid. One should be willing to examine one's own arguments for logical error and fallacy.

Now, it's a rather simple and straightforward matter to prove that free will doesn't exist (if this is really what you want to do). You must first disprove dualism (because a spiritual or mental existence seperate or undetectable from the world we experience allows for the concept of a soul that allows free will) and to prove that TLOP is purely deterministic.

Several pages of several threads threads have been wasted arguing over that flawed syllogism, when it could have simply been corrected. Instead, several weeks or more have been wasted in a non-argument, and neither side has shared any views or provided any worthwhile information.

Hopefully you will take my corrections in the spirit in which they were posted (to move the argument along and, perhaps, make it productive).

Another tactic might be to ask everyone to simply accept, for the sake of your argument, that free will is an illusion and does not exist, then work from there to present your case. If you are interested in sharing your knowledge, this would be a far more productive path.

Taking an immediate adversarial attitude to anyone who points out percieved errors or asks for clarification will not lead to any sharing of knowledge, and is, I suspect, the main reason for your treatment here. This last paragraph is, of course, simply my opinion, but it is offered in good faith. I do hope you consider it.

Sincerely,
Huntsman
 
Franko said:
Are you claiming that You are NOT made of atoms?

Are you claiming that Atoms do NOT obey the Laws of Physics

Are you claiming that YOU CAN DISOBEY THE LAWS OF PHYSICS???

OKAY!!! I hear you! Just do IT ... and shut me up once and for all!

What is with you nutty A-Theists?

Put up or shut up!

I do not believe anyone is necessarily questioning the truth of your syllogism. They are merely pointing out its logical error, thus rendering it invalid as any sort of proof of anything.
 
a_unique_person said:


I have found plenty of the sites that have the logical fallacies, but I want to find out what it is rather than what it is not.

Okay, I am honestly confused now.

What "it" are you referring to now? Fallacy of Composition, or Logical Fallacies in general?

Please ask your question again :confused:
 
a_unique_person said:


Thanks, that's more like it. Other sites I found were a bit more opaque.

Logic can get very dry, but I am happy to be of service.

The most basic way of looking at logic, is to think of it as a consistency check. It sorts out what is and is not consistent, but can't be used by itself to determine truth :)
 
The orders of abstraction, and its mappings!

TO FADE

Fade wrote 10-29-2002 04:49 AM: That's basically the whole of it. C is a letter. A is a letter. T is a letter. CAT is not a letter.

Soderqvist1: CAT is only letters here, because you have not defined the word Cat!

Fade even wrote: While it is possible to arrive at a conclusion which is broadly correct, it is still a fallacy to arrive at the conclusion due to assuming it's property. For instance: Cats are animals. Kittens are animals. A litter of kittens are animals.

Soderqvist1: You have defined Cats as animals here, not letters, and therefore; Cats are animals, and kittens are animals, and a litter of kittens are animals too! These letters of Cat is a word, which is only a symbol for a real thing in the world, some animal, and the word cat is not the object we are speaking about, because a map is not the territory, it is only an description, not the territory itself, the reason is simple because; I am a owner of a map here, but I don't own any country, hence it follows from that, that the map is not the territory, and furthermore; a map cannot describe all its territory, because our world is a dynamic entity, and thus changes all the time, but a real map is static in its context, but the materials which this map is made of, fade away through time, as all real objects do!

Formal logic has its limits, for instance, all Cretans are liars, and when one Cretan say; I am a liar, he is not a liar, because he has admit that he is liar, and if it is lie, it is the truth anyway, that a Cretan is a liar! And the genuine skeptic who has alleged that, that he doesn't know anything, it is not truth, because he knows that, that he doesn't know anything! ;)
 
I don't know if you're being facetious or not Peter, but:

Soderqvist1: You have defined Cats as animals here, not letters, and therefore; Cats are animals, and kittens are animals, and a litter of kittens are animals too!

While the conclusion is true, it doesn't follow from the premise. One can not assume a property of the whole solely by it's component parts.

A litter of kittens are animals because of the definition of "animal" not because kittens are animals.

Many of us excercise illogic in our every day lives, because the end result works, regardless of the error.
 
Discriminate between the orders of abstractions!

TO FADE

Fade wrote 10-29-2002 08:36 AM: While the conclusion is true, it doesn't follow from the premise. One cannot assume a property of the whole solely by its component parts. A litter of kittens are animals because of the definition of "animal" not because kittens are animals. Many of us exercise illogic in our every day lives, because the end result works, regardless of the error.

Soderqvist1: My way of arguing is not holistic, nor reductionistic, but something between these extremes! Cat, or act, t a c , are only undefined letters in our premise number1.

Cats are obviously animals by your definition inside your premise number 2.

Premise number 1 is not premise number 2, they are therefore only consistent on their own levels, but they are illogical as you have said, if we intermix, or confuses them, so don't do that! ;)
 
The problem with many of these allegedly fallacious arguments is that the premisses are true and the conclusion is true, but the conclusion does not follow by necessity from the premisses.

You must examine the formal structure of the argument to spot the fallacy, not the truth value of the propositions.

The form should be

If the premisses are true, then the conclusion must also be true.

If the conclusion can be false while the premisses are true, then the argument is invalid. This is the basis for reductio ad absurdem.

From contradictory premisses, anything can be inferred.

A valid argument may contain false premisses and a false conclusion. A sound argument is a valid argument with true premisses. Logic doesn't generally care if the argument is sound, only that it is valid.
The fallacy of composition is a formal fallacy, like affirming the consequent, and has nothing to do with the truth of the component propositions.

Couple of fallacies and valid arguments for examples

Affirming the consequent:

If A then B
B
Therefore A - invalid.

Denying the consequent (modus tollens)

If A then B
Not B
Therefore not A - valid

Affirming the antecedant (modus ponens)

If A then B
A
Therefore B - valid

Composition

A (and B and C...) have property X
Y is made A (and B and C...)
Therefore Y has property X.

All three statements MAY be true, but the conclusion does not follow. (Hydrogen and Oxygen are gases at room temperature, water is made of hydrogen and oxygen, therefore water is a gas at room temperature)

Division
A has property X
A is made of B (and C and D...)
Therefore B (and C and D...) have property X. - Invalid

I got a million of them
 
Whitefork,

Keep posting like that and I am going to have to find my old text book just to keep up. I cannot remember the title, but the fallacy examples were funny. They even used the Marx Brothers for ambiguity:

I shot an elephant in my pajamas.

What was an elephant doing in your pajamas?
 

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