Family resemblance

As a family resemblance (English family resemblance or family likeness, cluster definition) refers to Ludwig Wittgenstein ( 1889-1951 ) in his Philosophical Investigations (1953 ) Properties of terms with a taxonomic classification ( hierarchical classification ) can not be adequately covered without is " the mind gets bumps " (I 119); because terms may have blurred, fuzzy boundaries. The family resemblance is - logically speaking - a class- forming equivalence relation: reflexive, symmetric and transitive.

As examples Wittgenstein calls the concept of language, the language of the game and the game; there is no general features that would apply to all languages ​​, games, and language games. While there are some games with common characteristics, but ever again have other no similarities: " Board games, card games, ball games, fighting games ," etc. can not be classified taxonomically, because they are related to each other via so-called family resemblances (I 66 f ). Games therefore constitute a family. In the Philosophical Investigations Wittgenstein spoke pictorially from the fact that certain terms mesh individual cases such as fibers of a thread.

Wittgenstein illustrates his examples with the limits of hierarchical classification ( see also universals ) and shows with his approach of family resemblances same time also an alternative to. The considerations of Wittgenstein have required fundamental importance for the rejection of an ideal of exactness, the necessary and sufficient conditions for a definition. Terms can also be fuzzy and based on paradigmatic cases of application, an analysis is not necessary to control them or to explain. The family resemblance comparable concepts have been used in the past, such as John Stuart Mill, Nietzsche, among others

Applications

Application has gained Wittgenstein's notion of family resemblance, for example, in the prototype theory (see also prototype semantics) of Eleanor Rosch. The prototype theory makes it possible even in cases where there is no necessary and sufficient criteria can be specified to classify an object in a category, perform such categorization makes sense. Membership in a category is defined here as the distance to a prototype, which is regarded as a central member of the category.

Examines the concept of family resemblance by Stegmüller was. Stegmüller uses the concept within its structuralist theory concept by conceives the set of intended applications of a theory as a paradigmatic set amount, according to the concept of family resemblance. He points out that the concept of family resemblance, although concerns categories for which no necessary and sufficient criteria can be specified to indicate the membership or non-membership for each object unambiguously. However, it is quite necessary conditions are stated which an object must meet in order to be a member of a category. Where an object that is not a necessary condition, it can be definitely excluded from the category. One can, however, even for those objects which fulfill the necessary conditions, do not specify a sufficient condition to ensure the membership in a category. It connects with the concept of family resemblance exactness in terms of the necessary conditions for belonging to a category with a inexactitude on the sufficient conditions for membership.