Douglas Stanley-Jones was born in London on 2 February 1905. His father, Herbert Stanley-Jones, was a chartered accountant. His mother, Florence Eliza née Parry was the daughter of William Parkes Parry, a wholesale pharmacist, and the sister of Leonard Arthur Parry MD FRCS. Douglas was educated at Whitgift Grammar School, Croydon. He won an open scholarship in science to St Bartholomew's. After qualifying in 1929, he did junior posts at the Albert Dock and Bristol General Hospitals. In 1936, he bought a practice in West Cornwall, where he worked as a family practitioner over an extensive rural area, combining this with surgery. He was the only FRCS in Cornwall at that time and during the war he was also a district medical officer of health. He continued to operate as an 'honorary' at the local voluntary hospitals, and after the war he began to work towards his dream of having his own surgical nursing home, but its opening coincided with the inauguration of the NHS and it did not prove viable. In the fifties, he immersed himself in reading and writing about neurophysiology, publishing his theories on topics ranging from the evolution of the optic chiasma to the role of the hypothalamus in emotion, and applying the new science of cybernetics to physiology - for which he coined the term 'kybernetics'. He published three books on this topic: *Structural psychology* (Bristol, J Wright, 1957), *Kybernetics of natural systems* (Oxford, Pergamon, 1960) and *Kybernetics of mind and brain* (Illinois, Charles C Thomas: American Lecture Series, 1970). This work aroused considerable interest in the USA and he was invited to lecture at universities and medical centres across America. In the fifties he also founded the Full Circle Foundation for Education and Research, of which he was director, to formalise his interest in intelligence and education. He successfully coached his own children, grandchildren and groups of local children in subjects ranging from classical Greek and Latin, to history, physics, chemistry and biology. From the seventies, he became involved in teaching at camps and summer schools for gifted children. He was made a bard of the Cornish Gorseth in the early fifties for his contribution to knowledge of the geology, industrial history and archaeology of Cornwall. He married Irene Katherine Fox in 1936. They had two sons, Kenneth and Geoffrey, and two daughters: both sons (who predeceased him) became consultant anaesthetists; the younger daughter is also a doctor. He died on 21 January 1999, just before his 94th birthday.