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Proof by example (also known as inappropriate generalization) is a logical fallacy whereby one or more examples are claimed as "proof" for a more general statement.〔http://www.auburn.edu/~marchjl/fallacies.htm〕 This fallacy has the following structure, and argument form: Structure: :I know that X is such. :Therefore, anything related to X is also such. Argument form: :I know that x, which is a member of group X, has the property P. :Therefore, all other elements of X have the property P. The following example demonstrates why this is a logical fallacy: : I've seen a person shoot someone dead. : Therefore, all people are murderers. The flaw in this argument is very evident, but arguments of the same form can sometimes seem somewhat convincing, as in the following example: :I've seen Gypsies steal. So, Gypsies must be thieves. ==When valid== However, argument by example is valid when it leads from a singular premise to an ''existential'' conclusion. For example: :Socrates is wise. :Therefore, someone is wise. (or) :I've seen a person steal. :Therefore, people can steal. This is an informal version of the logical rule known as existential introduction (also known as ''particularisation'' or ''existential generalization''). Formally ;Existential Introduction: : : 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Proof by example」の詳細全文を読む スポンサード リンク
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