- Texas sharpshooter fallacy
The Texas sharpshooter fallacy is a
logical fallacyin which information that has no relationship is interpreted or manipulated until it appears to have meaning. The name comes from a story about a Texan who fires several shots at the side of a barn, then paints a target centered on the hits and claims to be a sharpshooter.
The fallacy does not apply if one had an "ex ante", or prior, expectation of the particular relationship in question before examining the data. For example one might, previous to examining the information, have in mind a specific physical mechanism implying the particular relationship. One could then use the information to give support or cast doubt on the presence of that mechanism. Alternatively, if additional information can be generated using the same process as the original information, one can use the original information to construct a hypothesis, and then test the hypothesis on the new data. See
hypothesis testing. What one "cannot" do is use "the same" information to construct "and" test the same hypothesis — to do so would be to commit the Texas sharpshooter fallacy.
The fallacy is related to the
clustering illusion, which refers to the tendency in human cognitionto interpret patterns in randomness where none actually exist.
* Attempts to find cryptograms in the works of William Shakespeare, which tended to report results only for those passages of Shakespeare for which the proposed decoding algorithm produced an intelligible result. This could be explained as an example of the fallacy because passages which do not match the algorithm have not been accounted for. The fallacy could also be an explanation for cryptograms in the Bible.
Related logical fallacies
rouletteball has landed on odd numbers eight times in a row. Therefore, it's more likely to land on an even number next time." ( gambler's fallacy.)
* "More children in town A have leukemia than in town B. Therefore, there "must" be something wrong with town A." (
cum hoc ergo propter hocor post hoc ergo propter hoc.)
Correlative based fallacies
Moving the goalpost, a related fallacy used to obtain the opposite conclusion.
* [http://skepdic.com/texas.html Skepdic's Dictionary entry]
* [http://www.fallacyfiles.org/texsharp.html Fallacy files entry]
Wikimedia Foundation. 2010.
Look at other dictionaries:
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 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 of division — A fallacy of division occurs when one reasons logically that something true of a thing must also be true of all or some of its parts. An example: A Boeing 747 can fly unaided across the ocean. A Boeing 747 has jet engines. Therefore, one of its… … Wikipedia
Fallacy of the single cause — The fallacy of the single cause, also known as causal oversimplification, is a fallacy of questionable cause that occurs when it is assumed that there is a single, simple cause of an outcome when in reality it may have been caused by a number of… … Wikipedia
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
Gambler's fallacy — The Gambler s fallacy, also known as the Monte Carlo fallacy (because its most famous example happened in a Monte Carlo Casino in 1913), and also referred to as the fallacy of the maturity of chances, is the belief that if deviations from… … Wikipedia
Reification (fallacy) — Contents 1 Etymology 2 Theory 3 Difference between reification and hypostatisation … Wikipedia
Deductive fallacy — A deductive fallacy is defined as a deductive argument that is invalid. The argument itself could have true premises, but still have a false conclusion. Thus, a deductive fallacy is a fallacy where deduction goes wrong, and is no longer a… … Wikipedia
Continuum fallacy — The continuum fallacy (also called the fallacy of the beard, line drawing fallacy, bald man fallacy, fallacy of the heap, and the sorites fallacy) is an informal logical fallacy closely related to the sorites paradox, or paradox of the heap.… … Wikipedia
Conjunction fallacy — The conjunction fallacy is a logical fallacy that occurs when it is assumed that specific conditions are more probable than a single general one. The most often cited example of this fallacy originated with Amos Tversky and Daniel Kahneman:… … Wikipedia