Biography:Tony Hoare

From HandWiki
Short description: British computer scientist

Tony Hoare

Sir Tony Hoare IMG 5125.jpg
Tony Hoare in 2011
Charles Antony Richard Hoare

(1934-01-11) 11 January 1934 (age 89)
Colombo, British Ceylon
Other namesC. A. R. Hoare
Spouse(s)Jill Pym
Scientific career
FieldsComputer science

Sir Charles Antony Richard Hoare (Tony Hoare or C. A. R. Hoare) FRS FREng[1] (born 11 January 1934)[2] is a British computer scientist who has made foundational contributions to programming languages, algorithms, operating systems, formal verification, and concurrent computing.[3] His work earned him the Turing Award, usually regarded as the highest distinction in computer science, in 1980.

Hoare developed the sorting algorithm quicksort in 1959–1960.[4] He developed Hoare logic, an axiomatic basis for verifying program correctness. In the semantics of concurrency, he introduced the formal language communicating sequential processes (CSP) to specify the interactions of concurrent processes, and along with Edsger Dijkstra, formulated the dining philosophers problem.[5][6][7][8][9][10] He is also credited with development (and later criticism) of the null pointer, having introduced it in the ALGOL family of languages. Since 1977, he has held positions at the University of Oxford and Microsoft Research in Cambridge.

Education and early life

Tony Hoare was born in Colombo, Ceylon (now Sri Lanka) to British parents; his father was a colonial civil servant and his mother was the daughter of a tea planter. Hoare was educated in England at the Dragon School in Oxford and the King's School in Canterbury.[11] He then studied Classics and Philosophy ("Greats") at Merton College, Oxford.[12] On graduating in 1956 he did 18 months National Service in the Royal Navy,[12] where he learned Russian.[13] He returned to the University of Oxford in 1958 to study for a postgraduate certificate in statistics,[12] and it was here that he began computer programming, having been taught Autocode on the Ferranti Mercury by Leslie Fox.[14] He then went to Moscow State University as a British Council exchange student,[12] where he studied machine translation under Andrey Kolmogorov.[13]

Research and career

In 1960, Hoare left the Soviet Union and began working at Elliott Brothers Ltd,[12] a small computer manufacturing firm located in London. There, he implemented the language ALGOL 60 and began developing major algorithms.[15][16]

He was involved with developing international standards in programming and informatics, as a member of the International Federation for Information Processing (IFIP) Working Group 2.1 on Algorithmic Languages and Calculi,[17] which specified, maintains, and supports the languages ALGOL 60 and ALGOL 68.[18]

He became the Professor of Computing Science at the Queen's University of Belfast in 1968, and in 1977 returned to Oxford as the Professor of Computing to lead the Programming Research Group in the Oxford University Computing Laboratory (now Department of Computer Science, University of Oxford), following the death of Christopher Strachey. He is now an Emeritus Professor there, and is also a principal researcher at Microsoft Research in Cambridge, England.[19][20][21]

Hoare's most significant work has been in the following areas: his sorting and selection algorithm (Quicksort and Quickselect), Hoare logic, the formal language communicating sequential processes (CSP) used to specify the interactions between concurrent processes (and implemented in various programming languages such as occam), structuring computer operating systems using the monitor concept, and the axiomatic specification of programming languages.[22][23]

Speaking at a software conference in 2009, Tony Hoare apologized for inventing the null reference:[24] [25]

I call it my billion-dollar mistake. It was the invention of the null reference in 1965. At that time, I was designing the first comprehensive type system for references in an object oriented language (ALGOL W). My goal was to ensure that all use of references should be absolutely safe, with checking performed automatically by the compiler. But I couldn't resist the temptation to put in a null reference, simply because it was so easy to implement. This has led to innumerable errors, vulnerabilities, and system crashes, which have probably caused a billion dollars of pain and damage in the last forty years.[26]

For many years under his leadership, Hoare's Oxford department worked on formal specification languages such as CSP and Z. These did not achieve the expected take-up by industry, and in 1995 Hoare was led to reflect upon the original assumptions:[27]

Ten years ago, researchers into formal methods (and I was the most mistaken among them) predicted that the programming world would embrace with gratitude every assistance promised by formalisation to solve the problems of reliability that arise when programs get large and more safety-critical. Programs have now got very large and very critical – well beyond the scale which can be comfortably tackled by formal methods. There have been many problems and failures, but these have nearly always been attributable to inadequate analysis of requirements or inadequate management control. It has turned out that the world just does not suffer significantly from the kind of problem that our research was originally intended to solve.

Awards and honours

  • Distinguished Fellow of the British Computer Society (1978)
  • Turing Award for "fundamental contributions to the definition and design of programming languages". The award was presented to him at the ACM Annual Conference in Nashville, Tennessee, on 27 October 1980, by Walter Carlson, chairman of the Awards committee. A transcript of Hoare's speech[28] was published in Communications of the ACM.[15]
  • Harry H. Goode Memorial Award (1981)
  • Fellow of the Royal Society (1982)[29]
  • Honorary Doctorate of Science by the Queen's University Belfast (1987)
  • Honorary Doctorate of Science, from the University of Bath (1993)[30]
  • Honorary Fellow, Kellogg College, Oxford (1998)[31]
  • Knighted for services to education and computer science (2000)
  • Kyoto Prize for Information science (2000)
  • Fellow[1] of the Royal Academy of Engineering[1] (2005)
  • Member of the National Academy of Engineering (2006) for fundamental contributions to computer science in the areas of algorithms, operating systems, and programming languages.
  • Computer History Museum (CHM) in Mountain View, California Fellow of the Museum "for development of the Quicksort algorithm and for lifelong contributions to the theory of programming languages" (2006)[32]
  • Honorary Doctorate from Heriot-Watt University (2007)[33]
  • Honorary Doctorate of Science from the Department of Informatics of the Athens University of Economics and Business (AUEB) (2007)
  • Friedrich L. Bauer-Prize, Technical University of Munich (2007)[34]
  • SIGPLAN Programming Languages Achievement Award (2011)[35]
  • IEEE John von Neumann Medal (2011)[36]
  • Honorary Doctorate, University of Warsaw (2012)[37]
  • Honorary Doctorate, Complutense University of Madrid (2013)[38]
  • 1973 ACM Programming Systems and Languages Paper Award,[39] for the paper "Proof of correctness of data representations"[40]

Personal life

In 1962, Hoare married Jill Pym, a member of his research team.[41]



  1. 1.0 1.1 1.2 "List of Fellows". 
  2. "Birthdays Jan 10". The Times (London). 10 January 2009. 
  3. Theories of Programming: The Life and Works of Tony Hoare. ACM Books. 39. New York, NY: Association for Computing Machinery. 2021. doi:10.1145/3477355. ISBN 978-1-4503-8728-6. 
  4. "Sir Antony Hoare". Computer History Museum.,Hoare/. 
  5. Tony Hoare author profile page at the ACM Digital Library
  6. {{DBLP}} template missing ID and not present in Wikidata.
  7. List of publications from Microsoft Academic
  8. Shustek, L. (2009). "Interview: An interview with C.A.R. Hoare". Communications of the ACM 52 (3): 38–41. doi:10.1145/1467247.1467261. 
  9. Hoare, C. A. R. (1974). "Monitors: An operating system structuring concept". Communications of the ACM 17 (10): 549–557. doi:10.1145/355620.361161. 
  10. Bowen, Jonathan (8 September 2006). "Oral History of Sir Antony Hoare". Hoare (Sir Antony, C.A.R.) Oral History, CHM Reference number: X3698.2007 (Computer History Museum). Retrieved 18 April 2014. 
  11. Lean, Thomas (2011). "Professor Sir Tony Hoare". National Life Stories: An Oral History of British Science. UK: British Library. 
  12. 12.0 12.1 12.2 12.3 12.4 Levens, R.G.C., ed (1964). Merton College Register 1900-1964. Oxford: Basil Blackwell. p. 434. 
  13. 13.0 13.1 Hoare, Tony (Autumn 2009). "My Early Days at Elliotts". Resurrection (48). ISSN 0958-7403. Retrieved 27 May 2014. 
  14. Roscoe, Bill; Jones, Cliff (2010). "1 Insight, inspiration and collaboration". Reflections on the Work of C.A.R. Hoare. Springer. ISBN 978-1-84882-911-4. 
  15. 15.0 15.1 Hoare, C.A.R. (February 1981). "The emperor's old clothes". Communications of the ACM 24 (2): 5–83. doi:10.1145/358549.358561. ISSN 0001-0782. 
  16. Hoare, C. A. R. (1981). "The emperor's old clothes". Communications of the ACM 24 (2): 75–83. doi:10.1145/358549.358561. 
  17. Jeuring, Johan; Meertens, Lambert; Guttmann, Walter (2016-08-17). "Profile of IFIP Working Group 2.1". 
  18. Swierstra, Doaitse; Gibbons, Jeremy; Meertens, Lambert (2011-03-02). "ScopeEtc: IFIP21: Foswiki". 
  19. Microsoft home page – short biography
  20. Oral history interview with C. A. R. Hoare at Charles Babbage Institute, University of Minnesota, Minneapolis.
  21. The classic article on monitors – The original article on monitors
  22. "Preface to the ACM Turing Award lecture". 
  23. "C. Antony (Tony) R. Hoare". 
  24. Hoare, Tony (25 August 2009). "Null References: The Billion Dollar Mistake". 
  25. "Null: The Billion Dollar Mistake". 
  26. Hoare, Tony (2009). "Null References: The Billion Dollar Mistake". QCon London. 
  27. Hoare, C. A. R. (1996). "Unification of Theories: A Challenge for Computing Science". Springer-Verlag. pp. 49–57. ISBN 3-540-61629-2. 
  28. Hoare, Charles Anthony Richard (27 October 1980). "The Emperor's Old Clothes: The 1980 ACM Turing Award Lecture". Association for Computing Machinery. 
  29. Anon (1982). "Anthony Hoare FRS". London: Royal Society. 
  30. "Honorary Graduates 1989 to present". University of Bath. 
  31. "(Charles) Antony Richard (Tony) Hoare Biography". 
  32. "Sir Antony Hoare: 2006 Fellow". "Sir Antony Hoare | Computer History Museum".,Hoare/. 
  33. "Annual Review 2007: Principal's Review". 
  34. "Preisverleihung auf der Festveranstaltung "40 Jahre Informatik in München": TU München vergibt Friedrich L. Bauer-Preis an Tony Hoare" (in de). Technical University of Munich. 26 October 2007. 
  35. "Programming Languages Achievement Award 2011". ACM. 
  36. "IEEE John von Neumann Medal Recipients". IEEE. 
  37. Krzysztof, Diks (15 November 2012). "Profesor Hoare doktorem honoris causa Uniwersytetu Warszawskiego" (in pl). University of Warsaw. 
  38. "Los informáticos Tony Hoare y Mateo Valero serán investidos hoy doctores honoris causa por la Complutense" (in es). 10 May 2013. 
  39. "ACM Programming Systems and Languages Paper Award". Association for Computing Machinery. 1973. Retrieved 2022-07-07. 
  40. Hoare, C.A.R. (1972). "Proof of correctness of data representations". Communications of the ACM 1 (4): 271–281. doi:10.1007/BF00289507. 
  41. Jones, Cliff; Roscoe, A. W.; Wood, Kenneth R., eds (2010). Reflections on the Work of C.A.R. Hoare. Springer Science. p. 3. 

External links