informal fallacies

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informal fallacies


Informal Fallacies

Informal FallaciesFallacyAn Error in Reasoning

To find out a fallacy is to identify the ways (recognizable patterns) in which one is tempted to reason incorrectly.

Incorrect Reasoning: Premises of an argument fail to support its Conclusion. E.g., all sciences are materialistic, Karl Marx was a materialist, therefore Karl Marx was scientific.

Formal Fallacies & Informal FallaciesType of Incorrect Argument

Formal Fallacy: Defect recognized in the form/structure of a deductive argument

Informal Fallacy: Defect due to the content of the language usedthe pitfalls laid by language in the way of a thinker

Classification of FallaciesIdentifiable Common Features

No indubitable Taxonomy of FallaciesTherefore, working classification (somewhat arbitrary)

Fallacies of RelevanceFallacies of Defective InductionFallacies of PresumptionFallacies of Ambiguity Fallacies of Relevance/IrrelevanceThe Appeal to the Populace (Argument ad Populum)The Appeal to EmotionThe Red HerringThe Straw ManThe Attack on the Person (Abusive/Circumstantial)The Appeal to ForceMissing the PointThe Appeal to the Populace (Argument ad Populum)Attempt to win popular assent to a conclusion by arousing the feeling of the peoplemobilizing public sentimentto excite enthusiasm/stir emotions (Appeal to emotion) Instead of providing convincing evidence and rational justification if one resorts to unduly invoking emotions, one commits a fallacy of this kind.

Patriotism & AdvertisementMany emotions are invoked and demands are pressed in the name of Nation and most of them in some sense seem justified. However, if the emotions are incited to garner support on illogical grounds, then the appeal becomes fallacious. For example, if a party demands vote in the name of religion, caste and region etc., it is not logically justified because the voters are supposed to vote on the merits of the candidate and the accidental facts like belonging to a religion or caste etc. do not constitute any merits which show the integrity and honesty of a candidate. P&A cont

ad Populum contMy party candidate is an accused person only, others have given tickets to criminals.There is a fallacy of bandwagon in the given example, because instead of providing any rational justification for why the party ticket is given to an accused person, the spoke person is pointing out that others are also doing the same. His reason is logically irrelevant to support his claim that giving ticket to a tainted person is necessary. Though it is psychologically appealing that a vicious person can very well overcome another vicious, but it is not necessary. A virtuous person can be a more potential candidate against the vicious ones. Argument ad Misericordiam (appeal to pity)Latin misericordiam means merciful heart. Mercy is a noble emotion and there is nothing wrong to appeal to this virtue. But if an undue appeal is made, then it becomes a fallacy. For example, a law officer commits this fallacy if he pleads for the leniency to his client, who killed his parents, on the grounds that he is an orphan. The Red HerringSome distraction is deliberately introduced to mislead or confuse to win the argument

Children are abused in New Delhi because there is a paucity of affordable child-care facilities.Here the scarcity of child-care facility (creche) is brought in to take away the attention from the deteriorating law and order situation in the national capital.The Straw Man FallacyPresenting an opponents position in a way easy to refute (may be a variety of red herring)

Assumption: opponents position is understood in its extremity

(a) Remarks by Mr. Mohan Bhagwat on reservation(b) Taking any remark too literally (donkey/dog)Argument Against the person (ad hominem)Argument Against the Person (abusive)Mr. Lalu Yadavs concern for corruption is not acceptable since he himself is convicted on corruption charges.

Argument Against the Person (circumstantial)Non-NET qualified students demand is not legitimate because those protesting belong to this category itselfAppeal to Force (Argument ad Baculum)Force or threat of force is pressed into service instead of any rational justification

E.g. if you do not agree with my view, you have to face the consequencesfundamentalistsMissing the Point (Ignoratio Elenchi)Such mistake is likely to be made when one seeks to refute anothers argument. Ignoratio elenchi is a mistaken refutationthe refutation goes haywire when the arguer fails to understand the position in dispute.E.g. Opposition says that the economic situation is worsening because the prices of everything are rising. Govt. says that economy is improving and we are conducting raids on the hoarders to keep the prices low non sequiturFallacies of Defective InductionThe Argument from Ignorance (ad ignorantiam): x is true because it is not proven to be falseapprehension towards any new thing is likely to involve this fallacy.Appeal to Inappropriate Authority (argument ad verecundiam): a conclusion is accepted to be true when an expert endorses. Obvious fallacy is seen where a non-experts advice is used to accept a conclusion.FDI contFalse Cause (argument non causa pro causa)when a non-cause is accepted as the cause of something, such fallacy is committed (WMD issue for UK)post hoc ergo propter hoc: after this, therefore because of thisFallacy of the slippery slope: change in one will lead to necessary change in the otherlikely (Collegium System Vs. NJAC)FDI contHasty Generalization:moving carelessly from short sample size to a general claim (converse accident)

Varun, Vipin, Vikas, Vaibhav, Vishakha are the students of SMVDU.Their name begins with a letter which is in the centre of SMVDU.Therefore, SMVDU admits only those whose name begin with V.Fallacies of PresumptionFallacy due to tacit assumption which is unwarranted, dubious or falseFallacy of Accident:Mistaken application of the general to special cases

Complex Question:Deceitful device: have you stopped beating your wife? FP contBegging the Question: (petitio principi)When the conclusion of an argument is assumed in any one of the premisesE.g. there is no such thing as knowledge which cannot be practiced, for such knowledge is no knowledge.Religious texts contain the message of God, they say that God exists, therefore we must accept that God exists.Fallacies of AmbiguityFallacy of Equivocation (due to more than one literal meaning) MMSFallacy of Amphiboly (fallacious due to grammatical construction) X, along with his wife, Y, donated his house for charityFallacy of Accent (shift in the emphasis) We should not speak ill of our friendsterms and conditions applyFallacy of Composition (features of parts to the whole)Fallacy of Division (reverse of the fallacy of composition)Mills MethodCause and Effect Relationship

The Method of AgreementThe Method of Disagreement/DifferenceThe Joint Method of Agreement and DifferenceThe Method of ResiduesThe Method of Concomitant Variation


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