The message in the Good Citizen letter to Sergeant John Lynch read "On occasion, while thinking of the code letters, the pencil wrote: Go to 56 Beach Street. I get the name Jerry, perhaps he knows people or his name is XXXXXXX". Cragle correctly concluded that this form of writing is called automatic writing or psychography, which is a claimed psychic ability allowing a person to produce written words without consciously writing. Scientists and skeptics consider automatic writing to be the result of the ideomotor effect and even proponents of automatic writing admit it has been the source of innumerable cases of self-delusion. Automatic writing is not the same thing as free writing. Spirit writing, later called Fuji (planchette writing), has a long tradition in China, where messages from various deities and spirits were received by mediums since the Song dynasty. In the 19th century, messages received through spirit writing led to the foundation of several Chinese salvationist religions. The spread of Chinese cultural techniques, such as printing and painting, introduced the influence of "spirit writing", practiced by Japanese Zen Ōbaku monks, who were said to communicate with an ancient Taoist sage credited with creation of the kung fu system. Parapsychologist William Fletcher Barrett wrote that "automatic messages may take place either by the writer passively holding a pencil on a sheet of paper, or by the planchette, or by a ouija board. In spiritualism, spirits are claimed to take control of the hand of a medium to write messages, letters, and even entire books. Automatic writing can happen in a trance or waking state. Some psychical researchers such as Thomson Jay Hudson have claimed no spirits are involved in automatic writing and the subconscious mind is the explanation. Wikipedia. So, it's pretty apparent the author of the Good Citizen letter was referring to spirit messages received through a planchette or ouija board.

It is clear that the author of the Good Citizen letter when referring to ESP and the pencil writing, was referring to messages received from the afterlife. Cragle pointed out that just six weeks later, on November 21st 1969, the Zodiac Killer mailed a communication directed towards Diane Kennedy Pike through the San Jose Police Department, that caused police to instigate 24-hour protection because of the threat on the widow. She had recently lost her husband, James Albert Pike (born February 14, 1913 – died September 3–7, 1969), who was an American Episcopal bishop, accused heretic, iconoclast, prolific writer, and one of the first mainline, charismatic religious figures to appear regularly on television. In 1966, after they had shared a sabbatical study at Cambridge University, Pike's son, Jim Jr., fatally shot himself in a New York City hotel room. Shortly after his son's death, Pike reported experiencing poltergeist phenomena—books vanishing and reappearing, safety pins open and indicating the approximate hour of his son's death, along with half the clothes in a closet disarranged and heaped up. Pike led a public pursuit of various spiritualist and clairvoyant methods of contacting his deceased son to reconcile. In September 1967, Pike participated in a televised séance with his dead son through the medium Arthur Ford, an ordained minister in the Disciples of Christ church. Pike detailed these experiences in his book The Other Side (released on January 1st 1968). In 1968, in defiance of C. Kilmer Myers, the Bishop who'd succeeded him, he married Diane Kennedy, a Methodist student twenty-five years his junior, with whom he had collaborated on The Other Side. Wikipedia
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