Barnum effect

Barnum effect is a term in psychology for a tendency to accept certain information to be true even when they are so vague as to be worthless, such as information given by an astrologer regarding character and predictions about the future based on horoscopes. This condition is named after P T Barnum, a US showman. The word Barnum became is use around mid 19th century which denoted a 'humbug or nonsense'.