Roberts took interest in
psychical research and
spiritualism, but approached these subjects from a mostly skeptical position. He was the author of
The Mysterious Madame: A Life of Madame Blavatsky (1931), a highly critical biography of
Helena Blavatsky. In his book
The Truth about Spiritualism (1932) he came to the conclusion that there is no evidence for the
spirit hypothesis in
mediumship. According to the research of Roberts all
séance and spiritualist phenomena can be explained by "telepathy, self-deception, fraud or neurosis". Roberts was convinced that the medium
Helen Duncan was a fraud and wrote a foreword to the book
The Trial of Mrs. Duncan (1945) by
Helena Normanton. ==Publications==