Why do street fortune tellers know my birthday?

A good forensic doctor can accurately judge a person's age, and an expert judge can judge a person's age, height, sex and daily behavior habits according to shoe prints, so if an expert judge comes to tell a fortune, what happened can almost be "calculated". There is a kind of "fantastic book" similar to modern psychology between fortune tellers and apprentices. When you ask thirteen questions, your past is revealed. Not based on modern theory (otherwise, it will be calculated by fortune tellers): fortune tellers ask your age and your wife's age to judge whether your ancestors have a deep shadow, ask where you live, and judge your occupation. , that is, the so-called "fishy and sharp, fighting for immortals", the accuracy rate decreases after death. If the phenomenon you are talking about is in the national security department, it is nothing, and the accuracy rate has not reached 100%, so I don't know what software to use in the street.