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Logic & Debate

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List of fallacies. A fallacy is incorrect argument in logic and rhetoric resulting in a lack of validity, or more generally, a lack of soundness. Fallacies are either formal fallacies or informal fallacies. Formal fallacies[edit] Main article: Formal fallacy Appeal to probability – is a statement that takes something for granted because it would probably be the case (or might be the case).[2][3]Argument from fallacy – assumes that if an argument for some conclusion is fallacious, then the conclusion is false.Base rate fallacy – making a probability judgment based on conditional probabilities, without taking into account the effect of prior probabilities.[5]Conjunction fallacy – assumption that an outcome simultaneously satisfying multiple conditions is more probable than an outcome satisfying a single one of them.[6]Masked man fallacy (illicit substitution of identicals) – the substitution of identical designators in a true statement can lead to a false one.

Propositional fallacies[edit] How to Understand Syllogisms: 5 Steps (with Pictures. Edit Article Edited by DifuWu, Eric, Chris Hadley, Codes for us and 4 others A syllogism is a logical argument composed of three parts: the major premise, the minor premise, and the conclusion inferred from the premises. The following steps will help you understand syllogisms. Ad Steps 1Know the basic structure of syllogisms. Bramantip (AAI): for example, All pigs are unclean. Tips Note that if either of the premises is negative, the conclusion must also be negative. Warnings Beware of the fallacy of the illicit major, where the major term is undistributed in the major premise but distributed in the conclusion. Fallacies. Dr. Michael C. Labossiere, the author of a Macintosh tutorial named Fallacy Tutorial Pro 3.0, has kindly agreed to allow the text of his work to appear on the Nizkor site, as a Nizkor Feature.

It remains © Copyright 1995 Michael C. Labossiere, with distribution restrictions -- please see our copyright notice. If you have questions or comments about this work, please direct them both to the Nizkor webmasters (webmaster@nizkor.org) and to Dr. Labossiere (ontologist@aol.com). Other sites that list and explain fallacies include: Constructing a Logical Argument Description of Fallacies In order to understand what a fallacy is, one must understand what an argument is. There are two main types of arguments: deductive and inductive. A fallacy is, very generally, an error in reasoning. Common fallacies.

List of common fallacies Compiled by Jim Walker originated: 27 July 1997 additions made: 01 Dec. 2009 You don't need to take drugs to hallucinate; improper language can fill your world with phantoms and spooks of many kinds. -Robert A. Wilson When arguing with someone in an attempt to get at an answer or an explanation, you may come across a person who makes logical fallacies. Such discussions may prove futile. You might try asking for evidence and independent confirmation or provide other hypotheses that give a better or simpler explanation. If this fails, try to pinpoint the problem of your arguer's position. You might spot the problem of logic that prevents further exploration and attempt to inform your arguer about his fallacy. The following briefly describes some of the most common fallacies: ad hominem: Latin for "to the man.

" William D. Logic in Argumentative Writing. Fallacy List. 1. FAULTY CAUSE: (post hoc ergo propter hoc) mistakes correlation or association for causation, by assuming that because one thing follows another it was caused by the other. example: A black cat crossed Babbs' path yesterday and, sure enough, she was involved in an automobile accident later that same afternoon. example: The introduction of sex education courses at the high school level has resulted in increased promiscuity among teens.

A recent study revealed that the number of reported cases of STDs (sexually transmitted diseases) was significantly higher for high schools that offered courses in sex education than for high schools that did not. 2. SWEEPING GENERALIZATION: (dicto simpliciter) assumes that what is true of the whole will also be true of the part, or that what is true in most instances will be true in all instances. example: Muffin must be rich or have rich parents, because she belongs to ZXQ, and ZXQ is the richest sorority on campus. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.