Logic Fallacies

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Logic Fallacies

Post by Straha »

Since many of those new to us apparently don't understand what logical Fallacies are I guess I should enlighten them:


1. Straw Man argument(sometimes referred to as the false dilemma argument): This is where you make a false statement for the opposing side and then knock it down. "Evolutionists say that all life came from nothing and this violates the second law of thermodynamics."

2. Ad hominem(against the man) Fallacy: This is where you direct the argument directly against the opponent. "You are A mother F*cking faggot whose IQ is less then a canine crossbred with pubic lice."
This however is not the same as an attack against the man from the argument. "From what you previously said I gather you are either a Neo-Nazi or A communist"

3. Ad infinitum Fallacy (sometimes called the slippery slope): This is where you base your argument on a simple logical idea and extrapolate to an illogical idea from it. "Ice Cream has fat in it. Fat can lead to obesity and high cholesterol. Obesity and high cholesterol can lead to an increased risk of heart attack. A heart attack can kill you. Thus eating a single scoop of Ben and Jerry's ice cream will kill you."

4. False Analogy. This is where you take a set of facts and use an analogy to falsify them and to perform a miniature slippery slope at the same time. "Evolutionists say birds evolved from dinosaurs, dinosaurs are reptiles, alligators are reptiles, and thus Evolutionists must say Birds evolved from alligators."

5. Appeals to authority. This is where you base an entire argument on what someone else said. This is not, however, when you make your argument and use what someone else said as backup. "Scientist John Doe said that evolution is impossible, thus it must be impossible."

6. Misrepresentation of Facts. This is when you take established fact, and use it to illogically prove a point. "Since half of the population spends an above median amount of time on the computer we must be wasting our life’s away." Or "Since half of the Black population scored beneath the median IQ score they must be stupider than whites, and thus should be enslaved."

7. Generalization. This is where you take one example of a thing, and use it to say all things are like that. "Since one of my friends was a sci-fi geek and was fat, all sci-fi geeks must be fat."

8. Misuse of the burden of proof. This is when you command the other person to prove the point when it is you who has to prove the point. The burden of proof becomes yours when you make a statement that goes against the current scientific or other standard. For instance you would have the burden of proof if you said "evolution is wrong, God made the world in seven twenty-four hour days, and the big bang theory and evolution are made by Atheistic scientists who want to separate you from god." Whereas you would not have the burden of proof if you said. "Black Holes have been proven to exist."

9. Tautologies (Sometimes refered to as circular logic). This is when you use your statement to prove your statement. "God exists because The bible says so, The bible is true becuase it was written by God."

EDIT: 8:23 9-20-02, added 9. More to come soon. And might I sugest this be made a sticky.
Last edited by Straha on 2002-09-20 08:23pm, edited 3 times in total.
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Post by Lagmonster »

I mentioned it in the 'Recommended Reading' thread over in the Off Topic section, but this seems another good place to pimp it:

The Elements of Reasoning by David A. Conway

This is a great place to begin and enhance your knowledge of how to argue, how to identify fallacies, and how to think logically. It's a cheap book, too. Amazon carries it, I believe.
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Post by TheDarkOne »

Ad hominem and other similar things are falacies of relevence, so you can have non-falacious forms of Ad hominem, and others. The fallacy only occurs when the appeal isn't relevent.
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Clarifications

Post by Patrick Degan »

Straha wrote:1. Straw Man argument(sometimes referred to as the false dilemma argument): This is where you make a false statement for the opposing side and then knock it down. "Evolutionists say that all life came from nothing and this violates the second law of thermodynamics."
Actually, the Strawman and the False Dilemma are two seperate fallacies. The False Dilemma involves setting up an "either all A or all B" situation. The Strawman is setting up a false argument which was never made in the first place for the express purpose of knocking it down and thereby hopefully scoring rhetorical victories.
8. Misuse of the burden of proof. This is when you command the other person to prove the point when it is you who has to prove the point. The burden of proof becomes yours when you make a statement that goes against the current scientific or other standard. For instance you would have the burden of proof if you said "evolution is wrong, God made the world in seven twenty-four hour days, and the big bang theory and evolution are made by Atheistic scientists who want to separate you from god." Whereas you would not have the burden of proof if you said. "Black Holes have been proven to exist."
The actual label for this fallacy is the Appeal to Ignorance. Generally, it runs along the lines of "unless you can absolutely prove A, you can't disprove B, can you?" and attempts to knot up a debator by either confusing him or setting up impossible conditions to meet the challenge. Usually also connected, at some level, with the False Dilemma fallacy. Whereas the example you give seems to be more a combination of the Tautology with the Ad Hominem attack (which often are also connected at some level).
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Post by haas mark »

I thought I might bump this. *bump*
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Post by Exonerate »

What about the Red Herring?

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Post by Larz »

Bait and switch is a nasty one, though I suppose thats more along the lines of a debate method, but it can be applied.
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Post by neoolong »

I found this site. It may prove helpful.

http://www.nizkor.org/features/fallacies/
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Post by haas mark »

Can this be stickied, by any chance?
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Post by Asst. Asst. Lt. Cmdr. Smi »

Actually, I think tautoligies and circular logic are different.

Visiting that link, I never knew there were so many fallacies...
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Post by neoolong »

Asst. Asst. Lt. Cmdr. Smi wrote:Actually, I think tautoligies and circular logic are different.

Visiting that link, I never knew there were so many fallacies...
Well considering how many ways people can be stupid...
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Post by Slartibartfast »

What kind of analogy would this be?
Thinking that somehow your argument/position is more valid on the grounds that you are being dispassionate ("coolness factor", also apathetic/indiferent) and the other person passionate. Then (optionally) start preaching about how being passionate is self-destructive and damaging of others. Ad hominem?
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Post by The Apologist »

Yes, an ad hominem indeed.
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Post by XaLEv »

The Apologist wrote:Yes, an ad hominem indeed.
Well, wasn't that random.
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Post by The Apologist »

How autological of you.
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Post by Coyote »

Here we go again.
Something about Libertarianism always bothered me. Then one day, I realized what it was:
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In Communism, there is no Government, so the Workers are free to exploit the Bosses.
So in Libertarianism, man exploits man, but in Communism, its the other way around!

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Re: Logical Fallacies

Post by THE AMBASSADOR »

Straha wrote:Since many of those new to us apparently don't understand what logical Fallacies are I guess I should enlighten them:


1. Straw Man argument(sometimes referred to as the false dilemma argument): This is where you make a false statement for the opposing side and then knock it down. "Evolutionists say that all life came from nothing and this violates the second law of thermodynamics."

2. Ad hominem(against the man) Fallacy: This is where you direct the argument directly against the opponent. "You are A mother F*cking faggot whose IQ is less then a canine crossbred with pubic lice."
This however is not the same as an attack against the man from the argument. "From what you previously said I gather you are either a Neo-Nazi or A communist"

3. Ad infinitum Fallacy (sometimes called the slippery slope): This is where you base your argument on a simple logical idea and extrapolate to an illogical idea from it. "Ice Cream has fat in it. Fat can lead to obesity and high cholesterol. Obesity and high cholesterol can lead to an increased risk of heart attack. A heart attack can kill you. Thus eating a single scoop of Ben and Jerry's ice cream will kill you."

4. False Analogy. This is where you take a set of facts and use an analogy to falsify them and to perform a miniature slippery slope at the same time. "Evolutionists say birds evolved from dinosaurs, dinosaurs are reptiles, alligators are reptiles, and thus Evolutionists must say Birds evolved from alligators."

5. Appeals to authority. This is where you base an entire argument on what someone else said. This is not, however, when you make your argument and use what someone else said as backup. "Scientist John Doe said that evolution is impossible, thus it must be impossible."

6. Misrepresentation of Facts. This is when you take established fact, and use it to illogically prove a point. "Since half of the population spends an above median amount of time on the computer we must be wasting our life’s away." Or "Since half of the Black population scored beneath the median IQ score they must be stupider than whites, and thus should be enslaved."

7. Generalization. This is where you take one example of a thing, and use it to say all things are like that. "Since one of my friends was a sci-fi geek and was fat, all sci-fi geeks must be fat."

8. Misuse of the burden of proof. This is when you command the other person to prove the point when it is you who has to prove the point. The burden of proof becomes yours when you make a statement that goes against the current scientific or other standard. For instance you would have the burden of proof if you said "evolution is wrong, God made the world in seven twenty-four hour days, and the big bang theory and evolution are made by Atheistic scientists who want to separate you from god." Whereas you would not have the burden of proof if you said. "Black Holes have been proven to exist."

9. Tautologies (Sometimes refered to as circular logic). This is when you use your statement to prove your statement. "God exists because The bible says so, The bible is true becuase it was written by God."

EDIT: 8:23 9-20-02, added 9. More to come soon. And might I sugest this be made a sticky.
I'd say I'm guilty of all of those now that I think about it.
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Post by Frank Hipper »

THE AMBASSADOR wrote:I'd say I'm guilty of all of those now that I think about it.
You should examine the rescources offered here before entering into a debate. Or, more to the point, before starting one. :wink:
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Post by Tom_Aurum »

Found a new one in a chat conversation. Well, maybe a new one. Don't know the word for it but for example.

"I hate plato."
"Maybe that's because you don't understand plato?"

No, I do understand Plato, I just don't agree with him.

Examplar two.

"You sure that you aren't just uncomfortable with your sexuality?"

No, I am comfortable with my sexuality. I'm just not gay.

Is there a particular term for this sort of logical fallacy?
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Post by Raoul Duke, Jr. »

Tom_Aurum wrote:Found a new one in a chat conversation. Well, maybe a new one. Don't know the word for it but for example.

"I hate plato."
"Maybe that's because you don't understand plato?"

No, I do understand Plato, I just don't agree with him.

Examplar two.

"You sure that you aren't just uncomfortable with your sexuality?"

No, I am comfortable with my sexuality. I'm just not gay.

Is there a particular term for this sort of logical fallacy?
I'm not sure what the term would be, but they both seem to be fairly simple in that they are based on hasty generalizations. In example 1, the assumption is that, "Everyone likes Plato." Well, some people do, certainly, but it's a HG to assume that everyone who understands Plato agrees with him.

The 2nd example assumes that, "Everyone is homosexual/bisexual," and that those who are sufficiently "comfortable with their sexuality" will go right out and learn the lyrics to Cabaret or something.

They appear to be either exactly the same fallacy, or close variations on a theme. What the title of the fallacy is, I have no idea.
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Post by Frank Hipper »

Variation on the theme of Appeal to Popularity perhaps?
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Post by Darth Wong »

Those are not fallacies because they are not arguments; they merely state opinions and make claims. A logical proposition takes the form "A therefore B".

In this case, the person simply states "I hate Plato" and when challenged, says he disagrees with him. There is no logical proposition there, hence no fallacy. You can say he's wrong, but until he tries to make some kind of logical proposition, it is impossible for a fallacy to be present.

Stating facts, even if those facts are false, is not fallacious. It may be incorrect, it may even be dishonest, but a logical fallacy invariably requires a proposition of the general form "A therefore B" in which A does not actually lead to B.
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Post by Tom_Aurum »

Actually, it is a fallacy, in assuming that you read A therefore you must be B. Ah, there we go, variation on generalization. <Thwaps self on forehead>. Experience generalization to be precise. For instance, similar assumption would be that if you had A seen this movie then you would have a fear of B object.
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Post by Raoul Duke, Jr. »

Darth Wong wrote:Those are not fallacies because they are not arguments; they merely state opinions and make claims. A logical proposition takes the form "A therefore B".

In this case, the person simply states "I hate Plato" and when challenged, says he disagrees with him. There is no logical proposition there, hence no fallacy. You can say he's wrong, but until he tries to make some kind of logical proposition, it is impossible for a fallacy to be present.

Stating facts, even if those facts are false, is not fallacious. It may be incorrect, it may even be dishonest, but a logical fallacy invariably requires a proposition of the general form "A therefore B" in which A does not actually lead to B.
See, my impression -- using example 1 -- is the following statement:

Everyone who understands Plato likes Plato. You do not like Plato; therefore, you do not understand Plato.

Which would, then, be an example of "A, therefore B." I think. I try never to be too sure of myself in these things.
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Post by Kuroneko »

Darth Wong wrote:Stating facts, even if those facts are false, is not fallacious. It may be incorrect, it may even be dishonest, but a logical fallacy invariably requires a proposition of the general form "A therefore B" in which A does not actually lead to B.
The only exception to this is when a singular fact is also an argument, but such creatures are limited to the domain of rule-based formal logic systems, which allow a proposition to be derivable from an empty set of premises.
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