Forer effect

The Barnum effect, also called the Forer effect, is a common psychological phenomenon whereby individuals will give high accuracy ratings to descriptions of their personality that supposedly are tailored specifically to them but that are, in fact, vague and general enough to apply to a wide range of people. This effect can provide a partial explanation for the widespread acceptance of some paranormal beliefs and practices, such as astrology, fortune telling, graphology, aura reading, and some types of personality tests.

The Forer effect is a specific example of the so-called "acceptance phenomenon", which describes the general tendency of humans "to accept almost any bogus personality feedback".

A related and more general phenomenon is that of subjective validation. Subjective validation occurs when two unrelated or even random events are perceived to be related because a belief, expectation, or hypothesis demands a relationship. For example, while reading a horoscope, people actively seek a correspondence between its contents and their perception of their personality.

The name "Barnum effect" seems to have originated with psychologist Paul Meehl in reference to the American circus entertainer P. T. Barnum, who is said to have stated that "there's a sucker born every minute".

The Forer effect is manifested in response to statements that are called "Barnum statements", meaning characterizations made about an interlocutor that the interlocutor finds valid even though the statements are generalizations that could apply to almost anyone. Such statements are used by fortune tellers, astrologers, and other practitioners of chicanery to convince customers that they, the practitioners, are in fact endowed with a paranormal gift.

In 1947, a psychologist named Ross Stagner asked a number of personnel managers to take a personality test. After they had taken the test, Stagner, instead of responding with feedback based on their actual individual answers, presented each of them with generalized feedback that had no relation to their test answers but that was, instead, based on horoscopes, graphological analyses, and the like. Each of the managers was then asked how accurate the assessment of him or her was. More than half described the assessment as accurate, and almost none described it as wrong.

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