Informal fallacy

Informal fallacy

An informal fallacy is an argument whose stated premises fail to support their proposed conclusion. [Kelley, D. (1994) "The Art of Reasoning". W W Norton & Company, Inc. ISBN 0-393-96466-3] The deviation in an informal fallacy often stems from a flaw in the path of reasoning that links the premises to the conclusion. In contrast to a formal fallacy, the error has to do with issues of ratiocination manifest in language used to state the propositions; the range of elements that can be symbolized by language is broader than that which the symbolism of formal logic can represent. Informal fallacies of deductive reasoning contain a fundamental disconnect between the premises and the conclusion that renders the argument invalid. This disconnect often stems from the presence of a hidden co-premise that, if presented, would validate the argument.

Inductive informal fallacies are slightly different than their deductive counterparts, as their merit rests in the inductive strength of the premise-conclusion link rather than in the presence of hidden premises. For instance, the fallacy of hasty generalisation, can be roughly stated as:

:p) "S" is a "P":p) "S" is also a "Q":c) therefore, all "P"s are also "Q"s

If the populations of "P" and "Q" are both too large to sample completely, then the statement is inductive. In such a case, a hasty generalization occurs when the number of "P"s and "Q"s is insufficient to represent the respective populations. [In other words, when you fail to mind your "P"s and "Q"s!] It is important to distinguish between a principle of reasoning (deductive or inductive) and the premise of an argument.

See also

* Argumentation theory
* Argument map
* Critical thinking
* Inference objection
* Inquiry
* Lemma
* Sophism

References

Further reading

* cite book
author = Damer, T. E.; Rudinow, J.; Barry, V. E.; Munson, R.; Black, A.; Salmon, M. H.; Cederblom, J.; Paulsen, D.; Epstein, R. L.; Kernberger, C.; Others,
title=Attacking Faulty Reasoning: A Practical Guide to Fallacy-Free Arguments
year = 2009
edition = 6E
url = http://www.duxbury.com/cengage/instructor.do?product_isbn=9780495095064&disciplinenumber=5
isbn = 9780495095064
publisher = Wadsworth

External links

* " [http://www.nizkor.org/features/fallacies/ Logical fallacies] " A list of logical fallacies, explained.
* " [http://www.napoletano.net/front/node/350 An Informal Fallacy Primer] "


Wikimedia Foundation. 2010.

Игры ⚽ Нужно сделать НИР?

Look at other dictionaries:

  • informal fallacy — noun A fallacy whose error cannot be represented by the symbols used in formal logic. Ant: formal fallacy …   Wiktionary

  • Informal logic — (or, occasionally, non formal logic) is the study of arguments as presented in ordinary language, as contrasted with the presentations of arguments in an artificial, formal, or technical language (see formal logic ). Informal logic emerged in… …   Wikipedia

  • Fallacy — In logic and rhetoric, a fallacy is usually incorrect argumentation in reasoning resulting in a misconception or presumption. By accident or design, fallacies may exploit emotional triggers in the listener or interlocutor (appeal to emotion), or… …   Wikipedia

  • fallacy, formal and informal — In philosophy, reasoning that fails to establish its conclusion because of deficiencies in form or wording. Formal fallacies are types of deductive argument that instantiate an invalid inference pattern (see deduction; validity); an example is… …   Universalium

  • Fallacy of prescience — See the term similar in meaning to prescience , precognition. A term used by Smith, DeShaye and Stoicheff to describe an erroneous exploratory research technique in which the experimental scaffolding embeds assumptions about what will be… …   Wikipedia

  • Fallacy of composition — The fallacy of composition arises when one infers that something is true of the whole from the fact that it is true of some part of the whole (or even of every proper part). For example: This fragment of metal cannot be broken with a hammer,… …   Wikipedia

  • fallacy — /fal euh see/, n., pl. fallacies. 1. a deceptive, misleading, or false notion, belief, etc.: That the world is flat was at one time a popular fallacy. 2. a misleading or unsound argument. 3. deceptive, misleading, or false nature; erroneousness.… …   Universalium

  • Fallacy of quoting out of context — The practice of quoting out of context, sometimes referred to as contextomy or quote mining , is a logical fallacy and a type of false attribution in which a passage is removed from its surrounding matter in such a way as to distort its intended… …   Wikipedia

  • FALLACY —    arguments which seem correct but upon examination prove false. They are arguments which are PSYCHOLOGICALLY persuasive but logically wrong through mistakes in relating, inferring, or concluding, while reasoning. TRADITIONAL logic identified… …   Concise dictionary of Religion

  • fallacy — Any error of reasoning. Reasoning may fail in many ways, and a great variety of fallacies have been distinguished and named. The main division is into formal fallacies in which something purports to be deductively valid reasoning but is not, and… …   Philosophy dictionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”