Medawar, Sir Peter Brian (1915–1987), biologist
by Avrion Mitchison, rev.

Medawar, Sir Peter Brian (1915–1987), biologist, was born on 28 February 1915 in Rio de Janeiro, the elder child and only son of Nicholas Agnatius Medawar, a Brazilian businessman of Lebanese extraction, and his British wife, Edith Muriel Dowling. He was educated at Marlborough College and Magdalen College, Oxford, where he took a first-class degree in zoology in 1935 and a DSc in 1947. At Oxford he was successively a Christopher Welch scholar and senior demy of Magdalen (1935), a senior research fellow of St John's (1944), and a fellow by special election of Magdalen (1938–44 and 1946–7). From 1947 to 1951 he was Mason professor of zoology in the University of Birmingham, from 1951 to 1962 Jodrell professor of zoology and comparative anatomy in University College, London, and from 1962 to 1971 director of the National Institute for Medical Research, Mill Hill. From 1971 to 1986 he was head of the transplantation section of the Medical Research Council's clinical research centre, Harrow.

Medawar created a new branch of science, the immunology of transplantation. During the battle of Britain in 1940 a plane crashed near his home in Oxford, and Medawar, engaged there in research on tissue growth and repair, was asked whether he could help the badly burnt pilot. Although he had nothing to offer at the time, this awoke in him an interest in transplantation of skin, which was to form the core of his scientific achievement. With the Glasgow surgeon Thomas Gibson he discovered the ‘homograft reaction’, the process whereby an immunological response causes the rejection of tissue that has been transplanted between unrelated individuals. It took another two decades and the work of many people to find ways of overcoming this reaction by means of immunosuppressive drugs, but it was Medawar's first decisive step that made possible organ transplantation as it was later known.

Along the way he and his small research group, especially Leslie Brent and Rupert Billingham, made other important discoveries, most notably of immunological tolerance in 1954. The immune system discriminates efficiently between skin grafts of foreign and self-origin, and under certain experimental conditions, which Medawar and his colleagues first defined, it can be misled into treating as self what is in fact foreign. Just as a new branch of surgery sprang from Medawar's seminal work on the homograft reaction, so also a new branch of developmental biology sprang from his work on tolerance. For this discovery he was awarded the Nobel prize for medicine in 1960, jointly with Macfarlane Burnet.

It must not be thought that a scientist as clear-minded and creative as Medawar was never wrong. Indeed, it is precisely those qualities which make his few mistakes easy to identify. A conspicuous example was his idea, during the early 1950s, that pigment spreads in the skin by cell-to-cell passage of infective particles.

To a wider public Medawar was known for his eloquent projection of ideas in and about biology. He was passionately convinced of the power of the scientific method not only to create what he called a magnificent ‘articulated structure of hypotheses’, but also to solve human problems. His deepest contribution was to expound the deductive view of scientific activity. For Medawar the place of honour is occupied by the ‘act of creation’, in which a new idea is formulated; experimentation has the humbler (but entirely necessary) role of verifying ideas. He happily accepted the consequence that an idea can never formally be proved true. Even the faintest whiff of induction was dismissed with contumely. He took pleasure in searching out the roots of this position in the English thinkers of the last three centuries. In all of this he was much influenced by his friends the philosophers T. D. (‘Harry’) Weldon, Sir Alfred Ayer, and Sir Karl Popper. He conveyed these convictions with eloquence, elegance, and an unfailing sense of humour in ten books published between 1957 and 1986—including The Uniqueness of the Individual (1957), The Future of Man (1960), Advice to a Young Scientist (1979), and The Limits of Science (1984)—and in some 200 articles and reviews. His Reith lectures (1959) on the future of man powerfully rejected the gloom-and-doom view of the impact of science on ordinary life. ‘Is the scientific paper a fraud?’ (BBC Third Programme, 1963, reprinted in his The Threat and the Glory, 1990) was much enjoyed in scientific circles.

His autobiography, Memoir of a Thinking Radish (1986), relates that the Oxford senior common rooms taught him to regard no subject as intellectually beyond his reach. Throughout his life he was quick to respond to the ideas of those around him: colleagues, students, friends, and family. How delighted were the undergraduates who attended his tutorials to find themselves acknowledged in his profound review in 1947 of cellular inheritance and transformation. He never ran a large laboratory, and even as director of the National Institute for Medical Research he and two or three junior colleagues occupied just two rooms (where he continued to do his own research and his own washing up, on the Tuesdays and Thursdays that he kept free of administrative duties). He laughed at gigantic research programmes, and at the possibility that government might perceive the practical benefits of research better than the individual scientist who carried it out. In his own experimental work, and above all in his writing, he set a standard which inspired the post-war flowering of immunology.

Medawar needed and received the total love and support of his wife, whom he married on 27 February 1937, from their first meeting as undergraduates at Oxford to his last paralysing illness. She was Jean Shinglewood Taylor [see ], daughter of Charles Henry Shinglewood Taylor, surgeon; they had two sons and two daughters. Jean entered fully into his professional life, filling first their house in Edgbaston, and then successively Lawn House and Holly Hill, their large houses in Hampstead, with his students and colleagues, many of whom became her own friends. They had a wide circle of friends in the media, in music, and especially in opera, which he enjoyed intensely. A sudden visit to Covent Garden or Glyndebourne was one of the joys of his University College days. His wife collaborated in his later writings, and maintained a strong interest in birth control and in the environment.

Medawar was tall, physically strong (an excellent cricketer), with a voice which could hold a lecture theatre in suspense or reassure a doubting student. Always accessible and open to argument, he had no doubts about his own capacity: sitting at his typewriter in University College, cigarette in his mouth, he told James Gowans that ‘It takes an effort to write undying prose’. His books are lucid and beautifully written.

Medawar was elected a fellow of the Royal Society (1949), appointed CBE (1958) and CH (1972), knighted (1965), and admitted to the Order of Merit (1981). He became an honorary FBA in 1981. He was an honorary fellow of many colleges and was awarded numerous honorary degrees. He received the Royal Society's royal medal in 1959, and its Copley medal in 1969.

During Medawar's last fifteen years at the clinical research centre at Harrow he was partially paralysed from a stroke suffered in 1969, while reading the lesson in Exeter Cathedral at the British Association for the Advancement of Science (of which he was president in 1968–9), but his ideas continued to flow, and he both inspired and received support from devoted colleagues. He suffered several more strokes and eventually died from one on 2 October 1987, in the Royal Free Hospital, London.



P. B. Medawar, Memoir of a thinking radish (1986) · N. A. Mitchison, Memoirs FRS, 35 (1990), 282–301 · personal knowledge (2004) · The Times (5 Oct 1987) · The Independent (5 Oct 1987) · The Guardian (9 Oct 1987) · m. cert. · CGPLA Eng. & Wales (1988)


Wellcome L., corresp. and papers |  Rice University, Houston, Texas, Woodson Research Center, corresp. with Sir Julian Huxley


photograph, 1960, Hult. Arch. · photograph, repro. in The Times · photograph, repro. in The Independent

Wealth at death  

£385,982: probate, 1988, CGPLA Eng. & Wales

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Sir Peter Brian Medawar (1915–1987): doi:10.1093/ref:odnb/40016