Recently I came upon a fascinating study by Richard Wiseman, a psychologist at the University of Hertfordshire. Wiseman surveyed a number of people and, through a series of questionnaires and interviews, determined which of them considered themselves lucky—or unlucky. He then performed an intriguing experiment: He gave both the “lucky” and the “unlucky” people a newspaper and asked them to look through it and tell him how many photographs were inside. He found that on average the unlucky people took two minutes to count all the photographs, whereas the lucky ones determined the number in a few seconds.

How could the “lucky” people do this? Because they found a message on the second page that read, “Stop counting. There are 43 photographs in this newspaper.” So why didn’t the unlucky people see it? Because they were so intent on counting all the photographs that they missed the message.