Wikipedia:Defining

This page explains how to apply the Defining concept in the context of Wikipedia categorization, by quoting the relevant guidance in several related guidelines.

From Wikipedia:Categorization § Defining

Here's how the DEFINING concept is described:

A central concept used in categorizing articles is that of the defining characteristics of a subject of the article. A defining characteristic is one that reliable sources commonly and consistently define the subject as having—such as nationality or notable profession (in the case of people), type of location or region (in the case of places), etc. For example, in Caravaggio, an Italian artist of the Baroque movement, Italian, artist, and Baroque may all be considered to be defining characteristics of the subject Caravaggio.

From Wikipedia:Categorization of people § Categorize by defining characteristics

Here's the application of DEFINING for the categorization of biographical articles:

Biographical articles should be categorized by defining characteristics. As a rule of thumb for main biographies this includes:

• standard biographical details: year of birth, year of death and nationality
• the reason(s) for the person's notability; i.e., the characteristics the person is best known for.

For example, a film actor who holds a law degree should be categorized as a film actor, but not as a lawyer unless their legal career was notable in its own right or relevant to their acting career. Many people had assorted jobs before taking the one that made them notable; those other jobs should not be categorized.

Similarly, celebrities commercializing a fragrance should not be in the perfumers category; not everything a celebrity does after becoming famous warrants categorization.

From Wikipedia:Overcategorization § Non-defining characteristics

Here's how DEFINING is applied in the context of overcategorization:

One of the central goals of the categorization system is to categorize articles by their defining characteristics. Categorization by non-defining characteristics should be avoided. It is sometimes difficult to know whether or not a particular characteristic is "defining" for any given topic, and there is no one definition that can apply to all situations. However, the following suggestions or rules-of-thumb may be helpful:

• a defining characteristic is one that reliable, secondary sources commonly and consistently define, in prose, the subject as having. For example: "Subject is an adjective noun ..." or "Subject, an adjective noun, ...". If such examples are common, each of adjective and noun may be deemed to be "defining" for subject.
• if the characteristic would not be appropriate to mention in the lead portion of an article, it is probably not defining;
• if the characteristic falls within any of the forms of overcategorization mentioned on this page, it is probably not defining.

Often, users can become confused between the standards of notability, verifiability, and "definingness". Notability is the test that is used to determine whether a topic should have its own article. This test, combined with the test of verifiability, is used to determine whether particular information should be included in an article about a topic. Definingness is the test that is used to determine whether a category should be created for a particular attribute of a topic. In general, it is much easier to verifiably demonstrate that a particular characteristic is notable than to prove that it is a defining characteristic of the topic. In cases where a particular attribute about a topic is verifiable and notable but not defining, or where doubt exists, creation of a list article is often the preferred alternative.

In disputed cases, the categories for discussion process may be used to determine whether a particular characteristic is defining or not. For example, there is consensus that places should not be categorised as established in the year of the earliest surviving historical record of the place.

See also

• Wikipedia:Categorization/Ethnicity, gender, religion and sexuality § General #6