Mind & EverydayFact
39 students got the same personality profile. All found it accurate.
In 1949 Bertram Forer gave his 39 students supposedly individual assessments – in fact the identical text, assembled from an astrology book. They rated its accuracy at 4.30 out of 5 on average. Vague statements that work in both directions fit almost anyone.
Useful: For any character description, ask: who would this sentence not fit?
Source: en.wikipedia.org