The strange case of the Reverend Ansel Bourne was described by William James in The Principles of Psychology. One morning in 1887, Bourne went to his bank and drew out the curious sum of $551; then he disappeared. His family were afraid he had been murdered. Two months later, in a town two hundred miles away, Bourne suddenly woke up and wondered where he was; he had no memories of how he came to be there. His neighbours thought he had gone mad, for they knew him as A J Brown, who had recently rented a newsagent’s shop in the area and was known as a good churchgoer.

Back in the bosom of his family, and with no memory of withdrawing the cash, travelling two hundred miles, or of renting a shop, Bourne allowed James to hypnotise him, hoping to find out what had happened. Under hypnosis, James was able to speak to Mr A J Brown, who claimed to be a totally different person from Bourne and insisted that he had never met him. But James never found out why Bourne had changed into another person and left home.

There were many interesting cases of ‘multiple personality’ around the beginning of