Kinsey Scale

The Kinsey scale, also called the Heterosexual–Homosexual Rating Scale, is used in research to describe a person's sexual orientation based on their experience or response at a given time. The scale typically ranges from 0, meaning exclusively heterosexual, to 6, meaning exclusively homosexual. In both the Male and Female volumes of the Kinsey Reports, an additional grade, listed as "X", was used to mean "no socio-sexual contacts or reactions". The reports were first published in Sexual Behavior in the Human Male (1948) by Alfred Kinsey, Wardell Pomeroy and others, and were also prominent in the complementary work Sexual Behavior in the Human Female (1953).

Introducing the scale, Kinsey wrote:

Males do not represent two discrete populations, heterosexual and homosexual. The world is not to be divided into sheep and goats. It is a fundamental of taxonomy that nature rarely deals with discrete categories... The living world is a continuum in each and every one of its aspects. While emphasizing the continuity of the gradations between exclusively heterosexual and exclusively homosexual histories, it has seemed desirable to develop some sort of classification which could be based on the relative amounts of heterosexual and homosexual experience or response in each history […] An individual may be assigned a position on this scale, for each period in his life. […] A seven-point scale comes nearer to showing the many gradations that actually exist.

The Kinsey scale ranges from 0, for those who would identify themselves as exclusively heterosexual with no experience with or desire for sexual activity with their same sex, to 6, for those who would identify themselves as exclusively homosexual with no experience with or desire for sexual activity with those of the opposite sex, and 1-5 for those who would identify themselves with varying levels of desire for sexual activity with either sex, including "incidental" or "occasional" desire for sexual activity with the same sex.

There have been similar studies where the scale is from 0 to 10. In such studies, the person would be asked a question such as "If 0 is completely gay and 10 is completely hetero, what is your orientation number?". Furthermore, the additional X grade used to mean "no socio-sexual contacts or reactions" is often today described as asexuality.

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