The most unlikely people can be easily gulled. Arthur Conan Doyle was a highly intelligent man of many passions. Most today consider him an exemplar of reason if only for his many stories of the world's first consulting detective. A physician, advocate for social justice, sharp-eyed recorder of the Boer War, a major author of historical novels, staunch advocate of vaccination, avid cricketeer, amateur boxer, playwright, reformer, Liberal Unionist candidate for Parliament, advocate for the wrongly accused, and a man interested in such varied topics as architecture and photography, Conan Doyle was a man of many parts and -- on the surface -- one unlikely to be fooled. Yet Conan Doyle for much of his life was a believer in psychic phenomena and an avowed spiritualist and, as such, was a believer in many hoaxes.
It is a misconception that Doyle turned to spiritualism because of and following the death of his son Kinsley but he publicly declared himself a spiritualist years before his son's death. The groundwork had been laid while attending Jesuit schools as a youth. Doyle soon rejected the Catholic faith and became an agnostic. A curiosity about psychic phenomena soon became a major interest. He attended about twenty seances, one of which convince him that psychic phenomena was real. Doyle also experimented with telepathy and met with various mediums. He was a founding member of the Hampshire Society for Psychical Research. He went searching for poltergeists in Devon. With the many losses of World War I on his mind, he came to the belief that spiritualism was a "revelation" sent by God to help eased the bereaved. His defense of spiritualism became a major part of his life and led him to support many instances that later were admitted to be hoaxes. And then there were the fairies.
In 1916, two cousins from the town of Cottingley begged one of their fathers for the use of his camera. The father finally agreed and put one photographic plate in the camera. The girls went out to play. coming back in an hour and insisting he develop the plate. The photo revealed ten-year-old Frances Griffiths surrounded by a ring of winged fairies. A later photographed showed 16-year-old Elsie Wright seated next to a gnome. (A few years later three more photographs were taken.) Stories of the photographs reach Doyle and he used them in an article for the The Strand Magazine in 1920. Doyle also got in contact with E. L. Gardner, a member of the executive committee of the Theosophical Society of England, who was undertaking and investigation of the Cottingley fairies. (The thread of Theosophy runs through Doyle's account. Many of the testimonies in The Coming of the Fairies are from Theosophists and are therefore credible in Doyle's mind, and Elsie Wright's parents, we are told, are Theosophists. Theosophy was a religion that knowledge of God can be obtained through spiritual means, intuition, and personal relationship, all mixed with a heady dose of mysticism. Theosophy was a popular movement in the late nineteenth and early twentieth centuries. Thin Scientology without the evil.)
Doyle never went to Cottingley and never met the two girls in question. He did however serve as conduit and cheerleader for Gardner, and gathering testimonials from persons throughout the world who claimed to have seen similar phenomena. One chapter in the book relates the experiences of a clairvoyant who explored the area with the two girls where they saw fairies, elves, brownies, water sprites, gnomes, and such. Of course the clairvoyant "saw" things the girls did not, and vice versa. Gardner Theosophical view of the fairies seems to be they are insubstantial elemental forces that are used by Nature to make plants grow by influencing the cells and roots (or something like that -- it's confusing). Once their work is done, the break down into constituent parts.
Fairies evidently live on a higher plane than we do and are visible usually in ranges above those normally seen by humans although children and certain talented individuals can see them. They evolved from insects (usually butterflies) and are intelligent (or are pretty dumb). They have a social hierarchy and love to dance and flit around. They do not fear humans and they fear humans. As mankind advances, many of those related to these creatures have passed into extinction (i.e., many of the mythological creatures of the past). And fairies may be "thought forms." Confused? I don't blame you.
Doyle tries to present himself as impartial on the subject, just presenting the facts so that the reader can decide for himself on the validity of fairies. He admits that the existence of fairies has not the definitive proof that seventy years of research behind spiritualism (ahem, **cough, cough**) but the evidence presented here makes a strong case for fairies (so sayeth the impartial reporter).
All of this is quackery of the highest sort, of interest to those interested in such and to those who wonder how and why Doyle went off the rails. A quick and totally unconvincing read.
It wasn't until the early eighties that both girls admitted the photos were a fake, made from cardboard cut-outs. Elsie died in 1988 and Frances in 1986. For six decades they had gulled the gullible.