Beloff was born and brought up in London, and was from a Russian
Jewish family. His parents were Semion (Simon) Beloff (born Semion Rubinowicz) and Maria (Marie) Katzin. His paternal great-grandmother was Leah Horowitz-Winograd, the sister of
Eliyahu Shlomo Horowitz-Winograd and a descendant of the Hasidic master
Shmelke Horowitz of Nikolsburg (1726–1778). He was the brother of the historian
Max Beloff, the politician and educationalist
Renee Soskin, the biochemist
Anne Beloff-Chain, and the journalist
Nora Beloff. He served in the British Army in the Second World War. He worked in an architect's office, then studied at
London University, where he graduated in 1952. Shortly after graduation he married Halla Parker, a fellow student of psychology who was ten years younger. Together, they spent a year at the
University of Illinois, and then enrolled on a doctorate programme at
Queen's University Belfast, defending their PhDs in 1956. In 1962 they both were offered jobs at the same department of University of Edinburgh and worked there until retirement. John and Halla had a daughter
Zoe, who became an international artist. Beloff had been interested in
parapsychology from an early age and served as president of the
Society for Psychical Research from 1974 to 1976. He was an executor of
Arthur Koestler's will in 1983 and was instrumental in setting up the first UK chair of parapsychology, the
Koestler Parapsychology Unit at Edinburgh in 1985. ==Reception==