Talk:Fallacy

Sore throat

Denying the antecedent--draws a conclusion from premises that do not support that conclusion by assuming Not P implies Not Q on the basis that P implies Q (e.g., If I have the flu, then I have a sore throat. I do not have the flu. Therefore, I do not have a sore throat. Other illnesses may cause sore throat.)

Actually, this argument is correct. It's a necessary condition (but not a sufficient condition). In other words; if the statement "having a flue" implies "having a sore throat"; then "no sore throat" implies "no flu". Please consider changing this description. 77.56.95.2 (talk) —Preceding undated comment was added at 23:24, 18 January 2009 (UTC).

But "no flu", doesn't imply "no sore throat", so you're wrong about the argument being correct. Remnant76 (talk) 15:24, 5 February 2009 (UTC)

You were confused with P implies Q being equivalent to Not Q implies Not P. So if Q is false, P also cannot be true (since P implies Q) (e.g., If I have the flu, then I have a sore throat. I do not have a sore throat. Therefore, I do not have the flu.)
--Shannonbay (talk) 06:25, 13 February 2009 (UTC)

True, sorry for that 77.56.85.5 (talk) 15:45, 22 February 2009 (UTC)

Accent

Accent, which occurs only in speaking and consists of emphasizing the wrong word in a sentence. e.g., "He is a fairly good pianist," according to the emphasis on the words, may imply praise of a beginner's progress, or an expert's deprecation of a popular hero, or it may imply that the person in question is a deplorable pianist.

Why is a citation needed here? All the statements can be logically attributed to the example given. Amnion (talk) 01:59, 26 February 2009 (UTC)

Needs reworking.

This article needs work. I've done a university level course in logic that covered this material and I was having a hard time following article. I cleaned up some of the examples and provided a couple more but more are needed. I think that some of the writing is too high level for an introductory article on logical fallacies. For example in the line about connotation fallacies there is a reference to dysphemistic words and attribution fallacies. While there are links that can be followed to learn what these are they weigh down the article. I found the article a tough slog because this sort of stuff.

It would also be good for someone to go through and clean up the style and grammar.Rmawhorter (talk) 18:48, 2 March 2009 (UTC)

Ambiguity

For the intent of the article and for the purpose of common understanding, I understand what is implied by ambiguous in the section Verbal Fallacies, Example 1. This ambiguity, however, struck me as being a little inappropriate in the context of the example. I could not find, in the article called Ambiguity any argument for ambiguity by multiple definitions as I feel was implied by this section. The closest I could find was ambiguity in semantics, but even this does not seem to fit. I could argue that technically all words are ambiguous, as their definitions rely on individual foreknowledge, definitions in various dictionaries (I know from recent experience, for example, that the definition for "hypocrisy" is very different in the American Heritage Dictionary from the one in the OED), translations, encyclopedias, reference texts, etc. We must agree, to avoid chaos, on some baseline correct interpretation. Therefore (perhaps in a sort of Orwellian fashion), the classification of "good" as "ambiguous" seems to be a little ambiguous itself. I vote that it be changed. Loonybin0 01:01, 2 May 2009 (UTC) —Preceding unsigned comment added by Loonybin0 (talk • contribs)

Small cleanup here

This line needs cleanup:

fallacies. – valid but unsound claims or bad nondeductive argumentation – .--Ihaveabutt (talk) 01:10, 16 May 2009 (UTC)

Doesn't make sense

The example doesn't agree with the problem. "Staff" should, perhaps, be replaced with "bricks" or similar, I think.

* Division, the converse of the preceding, arguing from a property of the whole, to each constituent part

Example Argument: "The university (the whole) is 700 years old, therefore, all the staff (each part) are 700 years old".

Problem: The materials used to build the university are older, because when the materials are formed, the university isn't formed yet.

--Chigozienri (talk) 23:17, 27 May 2009 (UTC)

Definition and summary

The definition and summary given at the top seem to be incorrect. The article states "A fallacy is an argument that is not logically valid."

However, several fallacies are logically valid. These include begging the question and the slippery slope fallacy.

In logic, validity normally refers to the link between premises and conclusion. To test validity, we imagine that the premises are true. On that assumption, we look for ways the conclusion could be false when the premises are true (counterexamples). If there is no imaginable counterexample, the argument is logically valid. In other words, if the truth of the premises on its own guarantees that the conclusion is true, the argument is logically valid.

That does not mean the argument is good. The premises may be false, or potentially false. But if they were true, the conclusion would have to be true.

The fallacy of begging the question assumes the truth of its conclusion in its premises. It is logically valid but bad reasoning.

A slippery slope fallacy presents a chain of "if...then..." conditional statements, which if true, guarantee that the conclusion is true. Some of these statements may be false (or likely to be false), in which case the chain will present bad reasoning.

For this reason, I edited the definition to [1]

This edit was reverted by User:Frozen4322 to restore the definition quoted above. The above definition is contradicted by examples in the article, and so needs reworking.

Jacobean Grid (talk) 09:38, 1 June 2009 (UTC)

appeal to authority is always a logical fallacy

I have doubts that this sentence would be how "appeal to authority" is conceived of in books on fallacies.

An appeal to authority ... can be appropriate form of rational argument

While appeal to authority might be practical and useful in life, and might be considered rational in public relations and ordinary life, the notion of fallacy as conveyed in logic is generally not concerned with those domains (where people are swayed merely by someone's credentials without evidence), but instead with a priori objectivity.

Yes, the statement also has no citation, but more problematic, the phrase "can be an appropriate form" seems breezy and editorial, like someone's own personal guess. --Ihaveabutt (talk) 06:41, 7 June 2009 (UTC)

Many Questions Fallacy

I don't believe that the "many questions" fallacy meets the requirements for a fallacy. As I understood it, though it isn't mentioned earlier in the article, a fallacy must be a statement, not a question. A question cannot be wrong or right, just resonable or not. —Preceding unsigned comment added by 207.255.218.162 (talk) 08:59, 4 July 2009 (UTC)

Criticism of logic

Many so-called logical fallacies appear to be based on the premise that all human beings share a common mode of logic. This itself could be a fallacy, since logic can become an ideology on its own, the fallacy of logical fallacy. Many of the newer thinkers of post-modernism, such as Feyerabend and Lyotard, have argued that much of rational and scientific discourse is based on ancient Greek philosophical ideas that are either outdated or that have turned out to be a kind of social construct, one that is true for those that accept it as true, but not for others. Hence, following this trend of thought, logic would in fact become exactly the same as magic, and their political and moral equality could no longer be questioned. ADM (talk) 06:53, 2 August 2009 (UTC)

That's an interesting idea...Indeed, my own mode of logic includes the fallacy of the existence of a fallacy of logical fallacy and the principle of autodoxastic universalization. Thus, from my perspective, your arguments fail and since this is my belief, by my principle of universailzation, it is everyones; thus, everyone believes you are wrong including you. I also have the principle of modal metamorphisis, in short, I can switch modalities at any time; thus, what is believed becomes what is true. By the way, please don't attempt to rebut what I've said, not only would that be intolerant of you, it would force me to write a large paragraph using absurdly large words ending with, "...And therefore, by deconstruction, and Lacan's principle of <insert funny misuse of topology>, I win." Seriously, no one wants that...Phoenix1177 (talk) 10:53, 11 August 2009 (UTC)

ADM, if you have a specific example of criticism of the idea of a fallacy, and reliable sources to establish that criticism, then by all means insert it. However, since deductive logic is built up from such straightforward principles such as, "If 'A and B' is true, then A is true," that it's hard to see how this is an "ideology" or "outdated". To criticise the claim that an argument is a fallacy, you need to show that the argument is actually deductively valid (or otherwise a good argument). Do you actually have sources to back that up? MartinPoulter (talk) 12:36, 11 August 2009 (UTC)

Eh, uh, øh... In what context is "fallacy" defined? (Imagine an insinuative tone here!) ... said: Rursus (^mbork³) 13:20, 30 December 2009 (UTC)

Couldn't resist answering myself. The intro starts with:

In logic and rhetoric, a fallacy is ...

Cheers! ... said: Rursus (^mbork³) 13:24, 30 December 2009 (UTC)

Straw Man

Corrected previous straw man example to a politically neutral argument. The previous one was politically charged and generally a weak illustration. --Nphyx (talk) 00:55, 30 August 2009 (UTC)

He is a fairly good pianist

A better example of this fallacy of accent placement would be "I didn't say he stole the money." It's far more emotionally charged and derives many more meanings. Just a suggestion. 206.24.49.1 (talk) 05:06, 15 September 2009 (UTC)

Section: "Fallacies in the media and politics"

Seeing as this section lacks any sources, is certainly POV, stinks of original research, and has been identified as such for 16 months, it's time to just get rid of it. dlainhart (talk) 18:33, 23 October 2009 (UTC)

I agree and have removed it. Here's the text in case someone wants to salvage some of it.

Fallacies in the media and politics

Fallacies are used frequently by pundits in the media and politics. When one politician says to another, "You don't have the moral authority to say X", this could be an example of the argumentum ad hominem or personal attack fallacy; that is, attempting to disprove X, not by addressing validity of X but by attacking the person who asserted X. Arguably, the politician is not even attempting to make an argument against X, but is instead offering a moral rebuke against the interlocutor. For instance, if X is the assertion:

The military uniform is a symbol of national strength and honor.

Then ostensibly, the politician is not trying to prove the contrary assertion. If this is the case, then there is no logically fallacious argument, but merely a personal opinion about moral worth. Thus identifying logical fallacies may be difficult and dependent upon context.

In the opposite direction is the fallacy of argument from authority. A classic example is the ipse dixit—"He himself said it" argument—used throughout the Middle Ages in reference to Aristotle. A modern instance is "celebrity spokespersons" in advertisements: a product is good and you should buy/use/support it because your favorite celebrity endorses it.

An appeal to authority is always a logical fallacy, though it can be an appropriate form of rational argument if, for example, it is an appeal to expert testimony . In this case, the expert witness must be recognized as such and all parties must agree that the testimony is appropriate to the circumstances. This form of argument is common in legal situations.

By definition, arguments with logical fallacies are invalid, but they can often be (re)written in such a way that they fit a valid argument form. The challenge to the interlocutor is, of course, to discover the false premise, i.e. the premise that makes the argument unsound.

MartinPoulter (talk) 18:40, 15 November 2009 (UTC)

begging the Q Circular Reasoning this is a BETTER EXAMPLE

fossils are dated by the type of stratum they are in, while at the same time the stratum is dated by the fossils found in it." An alternative evolutionarily statement is that "the fossils and rocks are interpreted by the theory of evolution, and the theory is proven by the interpretation given to the fossils and rocks."

a page teaching people what fallacy means is not the right place to attack people's beliefs and their reasons for believing certain immeasurable things in life, its meaning, the existence of God. who's to say the bible isn't divinely inspired ? if it is then it follows that everything it says is correct. in most courts of law that wouldn't be considered circular reasoning. the case for the bible being divinely inspired is stronger than the one against it, at least for anyone who thinks life has any meaning, and that society can't function without a moral compass, and that there are absolutes that govern the universe. that there's something an isolated, mentally challenged, crippled man can access and find hope, faith, and love in. Grmike (talk) 01:41, 11 November 2009 (UTC)grmike

Rock strata are dated directly by potassium radioactive decay, relatively by the level of the layer and the direct observation that sediments are deposited in newer layers over older as are volcanic flows. Direct observations of earthquakes and rift valleys explains curvatures in the layers. Fossils are identified with various layers and, along with chemical composition, texture, etc then are the fossils used to date the layers. Your original criticism was valid many years ago but not anymore. Alatari (talk) 08:06, 12 November 2009 (UTC)

Jeremy Butterworth

Argument: McDonalds soft serve ice creams are made purely from pig fat. Problem: No substantial evidence to support- this plays on the human emotion, that pig fat in your ice cream would be horrifying to eat. Jeremy Butterworth was found susceptible to this emotion.

Perhaps I missed something, but the last sentence seems completely out of place. I don't see how it adds anything to the example, if anything it is more akin to random trivia. Assuming Jeremy Butterworth is somehow related to the example and readers can make that correlation, the context is not even correct. The previous sentence is talking about human emotion in general. So this is either saying the he is susceptible to some unnamed human emotion, or that he has emotions in general, of which both contexts are irrelevant. Just pointing this out in case someone else feels the same way and wants to delete it it. Not a big editor, this just stuck out to me.

--174.52.7.12 (talk) 22:51, 14 November 2009 (UTC)

I know some people that fry everything in pig lard so I'm not sure every person would be disgusted. Maybe the wording is awkward but it still needs saying. Alatari (talk) 09:38, 15 November 2009 (UTC)

Upon closer examination it appears that was a vandalism that was overlooked. I rewrote to better clarify and remove vandalism. Alatari (talk) 09:46, 15 November 2009 (UTC)

Deletion of Fallacy of Emotion content

No reliable authoritative cite for such a fallacy by that term could be found this date: http://www.google.com/search?hl=en&as_q=&as_epq=Fallacy+of+Emotion&as_oq=&as_eq=&num=10&lr=&as_filetype=&ft=i&as_sitesearch=&as_qdr=all&as_rights=&as_occt=any&cr=&as_nlo=&as_nhi=&safe=off , just circular references to this Wikipedia article and informal use by individuals, possibly acquainted with it via same. There is a logical fallacy along these lines, just not named and stated as excised. Appropriately cited content on it is welcome. Wikiuser100 (talk) 16:00, 22 November 2009 (UTC)

Confusing Tag

I propose that we tag this article {{cleanup-confusing}}, because although the content of the article is generally good, it can be hard to follow (especially when printed). If I don't get responses, I think I'll just go ahead and add the tag. threecheersfornick (talk) 19:28, 30 December 2009 (UTC)

Wait, I guess this is included in the tag that's already there. Nevermind.threecheersfornick (talk) 01:08, 4 January 2010 (UTC)

Fallacy of Improperly Applying a Fallacy

Is there a special name for the fallacy of improperly applying a fallacy? Or would that be best to simply fall under Non Sequitur?

Example: If it were to be discovered that vaccines do in fact cause autism, then many former accusations of post hoc ergo propter hoc would be shown as fallacious. (That is, the bare bones claim could be correct in that the conclusion was reached through fallacious logic; however, the accuser in thinking that he had thus disproven the conclusion would also be committing his own logical fallacy.) Stated more generally:

Argument A is fallacious. Therefore, Argument A's conclusion C(A) is false.

This is a logic fallacy that I think deserves its own mention, and perhaps even its own name.

204.179.219.251 (talk) 18:20, 6 January 2010 (UTC)

Reasoning By Innuendo

Is it worth adding this term to the section on use of dysphemisms and/or reasoning by emotional appeal? This phrase always struck me as a good name for the concept. 204.179.219.251 (talk) 18:20, 6 January 2010 (UTC)

I found one source for this via Google Books (and two more scholarly sources which cited it), so I've added it. Thanks for the suggestion. MartinPoulter (talk) 19:31, 6 January 2010 (UTC)

God exists circular argument sources

From Gary Colwell's sources in his paper Informal Logic, Spring 1989:

• Michael A. Gilbert refers to this standard example of circular reasoning as "one more classic:" How to Win an Argument (New York: McGraw-Hill Book Company, 1979), p. 54.
• John Woods and Douglas Walton have produced a penetrating and sustained treatment of the fallacies in their work, Argument: The Logic of the Fallacies (Toronto: McGraw-Hill Ryerson Limited, 1982). They devote their entire Chapter Seven to the fallacy called" Arguing in a Circle. " They, too, give special attention to the standard example.
• Anthony Weston has written a popular, easy-to-read introduction to arguments, designed primarily as a freshman supplementary text to be read without the aid of a lecturer's commentary. A Rulebook for Arguments (Indianapolis: Hackett Publishing Company, 1987), p. 86. The one example that he uses to

illustrate the fallacy of Begging the Question is the same standard example to which the author of this paper is referring.

• Howard Kahane, Logic and Phi1osophy: A Modern Introduction, 5th ed. (Belmont, California: Wadworth Publishing Company, 1986), pp. 256, 257.
• S. Morris Engel, Analysing Informal Fallacies (Englewood Cliffs: Prentice-Hall Inc., 1980), p.55.
• Trudy Govier, A Practical Study of Argument. 2nd ed. (Belmont, California: Wadworth Publishing Company, 1988), p. 86;
• Robert J. Yanal, Basic Logic (St. Paul: West Publishing Company, 1988), p. 274.
• Jack Pitt and Russeli E. Leavenworth incorporate the notions of God, freedom and evil in their example. Logic for Argument (New York: Random House, 1968), pp. 113, 114.
• R.H. Iohnson and I.A. Blair use the idea of a rabbi who claims to dance with angels, in their illustration of begging the question. Logical Self Defense, 2nd ed. (Toronto: McGraw-Hill Ryerson Limited, 1983), p. 54.

Just because you don't like it doesn't mean it's not verifiable or notable. Alatari (talk) 11:29, 28 May 2010 (UTC)

Simplification Needed

Too many Latin terms are used in a confusing way in the article. I subit you should write them in English (the page’s language), then in Latin in parenthesis. An example of a good statement: “popular sentiment (argumentum ad populum--appeal to the majority; appeal to loyalty.)” Remember, this document wasn’t written for (nor in all likelihood by) people with doctorates, it was written for common people who may not necessarily understand a word you said.174.25.34.44 (talk) 05:08, 1 June 2010 (UTC)A REDDSON