Psychologist B.R. Forer found that people tend to accept vague and general personality descriptions as uniquely applicable to themselves without realizing that the same description could be applied to just about anyone. Consider the following as if it were given to you as an evaluation of your personality.
You have a need for other people to like and admire you, and yet you tend to be critical of yourself. While you have some personality weaknesses you are generally able to compensate for them. You have considerable unused capacity that you have not turned to your advantage. Disciplined and self-controlled on the outside, you tend to be worrisome and insecure on the inside. At times you have serious doubts as to whether you have made the right decision or done the right thing. You prefer a certain amount of change and variety and become dissatisfied when hemmed in by restrictions and limitations. You also pride yourself as an independent thinker; and do not accept others’ statements without satisfactory proof. But you have found it unwise to be too frank in revealing yourself to others. At times you are extroverted, affable, and sociable, while at other times you are introverted, wary, and reserved. Some of your aspirations tend to be rather unrealistic.
Forer gave a personality test to his students, ignored their answers, and gave each student the above evaluation. He asked them to evaluate the evaluation from 0 to 5, with ‘5’ meaning the recipient felt the evaluation was an ‘excellent’ assessment and ‘4’ meaning the assessment was ‘good.’ The class average evaluation was 4.26. That was in 1948. The test has been repeated hundreds of time with psychology students and the average is still around 4.2.