Are people basically the same or is everyone different? Yes. It’s intuitively obvious that all of us at some times need to be told that we’re special, and at other times need to be told that we’re not.
In 1948, psychologist Bertram Forer performed an experiment by giving his students a personality test and then providing each with a personality sketch that he said was based on their responses. In fact, the same sketch (thirteen statements largely assembled from a “newsstand astrology book”) was given to all of the students regardless of their responses. The students’ average rating of their sketch’s accuracy for them was 85%, and Forer believed that, by accepting the test as “a good or perfect instrument for personality measurement,” the students proved how gullible they were.
Indeed, the students’ “tendency to be overly impressed by vague statements and to endow the diagnostician with an unwarrantedly high degree of insight” should be troubling for anyone but the phony psychics, fortune tellers, and mind readers who make their living from it. But it seems to me that the most revealing aspect of the experiment is that you and I are enough alike to believe that the same personality profile applies convincingly to both of us.