Alasdair Ian Fenton Urquhart (; born 20 December 1945) is a Scottish–Canadian philosopher and emeritus professor of philosophy at the

University of Toronto The University of Toronto (UToronto or U of T) is a public university, public research university in Toronto, Ontario, Canada, located on the grounds that surround Queen's Park (Toronto), Queen's Park. It was founded by royal charter in 1827 ...

. He has made contributions to the field of

logic Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from premise ...

, especially

non-classical logic Non-classical logics (and sometimes alternative logics) are formal systems that differ in a significant way from standard logical systems such as propositional and predicate logic. There are several ways in which this is done, including by way of ...

. One of his ideas is proving the undecidability of the

relevance logic Relevance logic, also called relevant logic, is a kind of non-classical logic requiring the antecedent and consequent of implications to be relevantly related. They may be viewed as a family of substructural or modal logics. It is generally, but ...

R. He also published papers in

theoretical computer science computer science (TCS) is a subset of general computer science and mathematics that focuses on mathematical aspects of computer science such as the theory of computation, lambda calculus, and type theory. It is difficult to circumscribe the ...

venues, mostly on

mathematical logic Mathematical logic is the study of formal logic within mathematics. Major subareas include model theory, proof theory, set theory, and recursion theory. Research in mathematical logic commonly addresses the mathematical properties of formal ...

topics of relevance to computer science.

Early life

Urquhart is a native of Scotland. He received his MA in philosophy from the

University of Edinburgh The University of Edinburgh ( sco, University o Edinburgh, gd, Oilthigh Dhùn Èideann; abbreviated as ''Edin.'' in post-nominals) is a public research university based in Edinburgh, Scotland. Granted a royal charter by King James VI in 15 ...

in 1967. He then attended the

University of Pittsburgh The University of Pittsburgh (Pitt) is a public state-related research university in Pittsburgh, Pennsylvania. The university is composed of 17 undergraduate and graduate schools and colleges at its urban Pittsburgh campus, home to the univers ...

, receiving an MA and Ph.D. in 1973 under the supervision of

Alan Ross Anderson Alan Ross Anderson (1925–1973) was an American logician and professor of philosophy at Yale University and the University of Pittsburgh. A frequent collaborator with Nuel Belnap, Anderson was instrumental in the development of relevance l ...

and

Nuel Belnap Nuel Dinsmore Belnap Jr. (; born 1930) is an American logician and philosopher who has made contributions to the philosophy of logic, temporal logic, and structural proof theory. He taught at the University of Pittsburgh from 1963 until his reti ...

Career

From 1973 to 1975, Urquhart was an assistant professor at Erindale College,

University of Toronto Mississauga The University of Toronto Mississauga (UTM), also known as U of T Mississauga, is one of the three campuses that make up the tri-campus system of the University of Toronto. Located in Mississauga, Ontario, Canada, the campus opened in 1967 as Eri ...

. He became an associate professor there in 1975. Starting in 1986, Urquhart was a professor of philosophy at the

. From 1983 to 1989, Urquhart was a consulting editor for the ''

Journal of Symbolic Logic The '' Journal of Symbolic Logic'' is a peer-reviewed mathematics journal published quarterly by Association for Symbolic Logic. It was established in 1936 and covers mathematical logic. The journal is indexed by ''Mathematical Reviews'', Zentralb ...

''. He was also an editor of ''Canadian Philosophical Monographs''. In 2003, he became the managing editor of reviews for '' The Bulletin of Symbolic Logic''. He is currently on the Council of the Division for Logic, Methodology and Philosophy of Science and Technology of the International Union of History and Philosophy of Science and Technology (2020–2023).

Selected publications

* Urquhart, Alasdair and Rescher, Nicholas. ''Temporal Logic.'' New York'':'' Springer Verlag, 1971. * Urquhart, Alasdair. "The Undecidability of Entailment and Relevant Implication." ''

'' 49:4 (1984): 1059–1073. * Urquhart, Alasdair and Cook, Stephen A. "Functional Interpretations of Feasibly Constructive Arithmetic", '' Annals of Pure and Applied Logic'', 1993; preliminary version at STOC'89 * "The Complexity of Decision Procedures in Relevance Logic II", ''Journal of Symbolic Logic'' 64:4 (1999): 1774–1802.

References

External links

DBLP publications
{{DEFAULTSORT:Urquhart, Alasdair 1945 births Living people Alumni of the University of Edinburgh University of Pittsburgh alumni Scottish emigrants to Canada University of Toronto faculty Scottish logicians 20th-century Scottish mathematicians 20th-century Scottish philosophers Canadian logicians 20th-century Canadian mathematicians 20th-century Canadian philosophers