The Standard Model for Programming Languages: The Birth of a Mathematical Theory of Computation Simone Martini Universit`adi Bologna and INRIA Sophia-Antipolis Bologna, 27 November 2020 Happy birthday, Maurizio! 1 / 58 This workshop: Recent Developments of the Design and Implementation of Programming Languages Well, not so recent: we go back exactly 60 years! It's more a revisionist's tale. 2 / 58 This workshop: Recent Developments of the Design and Implementation of Programming Languages Well, not so recent: we go back exactly 60 years! It's more a revisionist's tale. 3 / 58 viewpoints VDOI:10.1145/2542504 Thomas Haigh Historical Reflections HISTORY AND PHILOSOPHY OF LOGIC, 2015 Actually, Turing Vol. 36, No. 3, 205–228, http://dx.doi.org/10.1080/01445340.2015.1082050 Did Not Invent Edgar G. Daylight the Computer Separating the origins of computer science and technology.Towards a Historical Notion of ‘Turing—the Father of Computer Science’ viewpoints HE 100TH ANNIVERSARY of the birth of Alan Turing was cel- EDGAR G. DAYLIGHT ebrated in 2012. The com- viewpointsputing community threw its Utrecht University, The Netherlands biggest ever birthday party. [email protected]:10.1145/2658985V TMajor events were organized around the world, including conferences or festi- vals in Princeton, Cambridge, Manches- Viewpoint Received 14 January 2015 Accepted 3 March 2015 ter, and Israel. There was a concert in Seattle and an opera in Finland. Dutch In the popular imagination, the relevance of Turing’s theoretical ideas to people producing actual machines was and French researchers built small Tur- Why Did Computer ing Machines out of Lego Mindstorms significant and appreciated by everybody involved in computing from the moment he published his 1936 paper kits. Newspaper and magazine articles ‘On Computable Numbers’. Careful historians are aware that this popular conception is deeply misleading. We by the thousands brought Turing’s life know from previous work by Campbell-Kelly, Aspray,Science Akera, Olley, Priestley, Make Daylight, Mounier-Kuhn, a Hero Haigh, story to the public. ACM assembled 33 and others that several computing pioneers, including Aiken, Eckert, Mauchly, and Zuse, did not depend on (let winners of its A.M. Turing Award to dis- alone were they aware of) Turing’s 1936 universal-machine concept. Furthermore, it is not clear whether any - ’S cuss Turing’s ideas and their relation- Out ofE Turing? substance in von Neumann’s celebrated 1945 ‘First Draft Report on the EDVAC’ is influenced in any identifiable - ship to the futureDOI:10.1145/2629499 of computing. Various way by Turing’s work. This raises the questions:Comparing (i) When the does legacy Turing of enterAlan theTuring field? in (ii) computer Why did science the Association written - HRISTI Maarten Bullynck, Edgar G. Daylight, and Liesbeth De Mol buildings, several roads, and at least for Computing Machinery- (ACM) honorwith Turing that by of associating Carl FriedrichC his name Gauss to ACM’sin mathematics. most prestigious award, the one bridge have been named after him. SY OF V E - Turing Award? Previous authors have been rather vague about these questions, suggesting some date between Dozens of books with Turing’s Viewpoint 1950 and the early 1960s as the point at which Turing is retroactively COURT integrated into the foundations of computing name in the title were published or re- Alan Turing (left); the cover page of Turing’s paper “On computable numbers, with E MAG issued. Turing was so ubiquitous that an application to theand Entscheidungsproblem” associating him in (right). some way with the movement to developI something that people call computer science. In UCH HAS BEEN R PE A Turing Talethis paper, based on detailed examination of hithertoVERY DISCIPLINE overlooked THAT primary sources, attempts are made to reconstruct BETHGE THOMAS BY PHOTOGRAPH even George Dyson’s book about John about Alan Turing dur von Neumann was titled Turing’sAssessing Ca -the accuracyStill, as of ingthis popular the floodnetworks past descriptions ofdecades Turing-related of and scholars andpoints ideas of prevalent Turing’s inactualof the age 1950s,career. consecrates andIn to RY; PA its identify own a specific group of ACM actors interested LLE of Alan Turing’s influencesby aand variety legacy. of people, in A thedral, becoming the first book on the material begins into recede theorizing it is time about to computations1936, just two in years computers afterroots completing in andthe process. attracted his InG to foot the idea of language as a frame in which to cluding historians, phi Eoccasions arenotes, found anecdotes, to remember and and names history of information technology to clean up some ofunderstand the rather bad computation. smell- undergraduate By going back degree, to Turing’she introduced 1936 paper and, more importantly, to re-cast versions of words meant exactly the same to every 8 reach a broad audience since the one ing historical claims left in our meta- thecelebrate concept nowpersonalitiesof called- departmental the andTuring ideas buildings,Ma that- Turing’s work published during the 1950s (Rosenbloom, Kleene, PORTRAIT Markov), I identify the factors that made thishistorical actor. In this Viewpoint, they a discipline considers its own. A dis L - about Nazis with punched card ma- phorical basement. Column space is chine in a paper called “On comput- refer to a large store inside the com group of scholars particularlycipline needs interested heroes into- help Turing’s create work a and providedcomes the original vector by which Turing chines. Publishers are well aware there short, so I will focus here on the idea able numbers, with an application to ATIONA 3 puter, containing both numbers and became to be appreciated in retrospect as the father of computerN science. is a strong audience for books about that Turing invented the computer.narrative the Entscheidungsproblem.” that legitimizes and fortifies This has instructions. According to the current SY OF Nazis. The public’s hunger for books Very shortlosophers, version: and it logicians. is wrong. Becomingits a ownsince identity. become Such the a mainnarrative abstract hard- mod- E state of the art in the history of comput about mathematicians and computer MIn caseTuring you scholarspent today2012 not in onlya maxi lyrequires reflects- el of the computation complexity usedof histori by computer- ing, the words “stored program” were archival research but also the study Com - introduced in 1949 by IBM engineers scientists is less acute, making Tur- mum-security prison or meditatingcal reality. scientists. Rather, itDuring echoes the the Secondset of World Martin Davis pre of several secondary sources. Doing 5,12 4 —two in Poughkeepsie,Although all NY. three Turing scholars preferences and programmatic choic ing’s newfound commercial clout both in a Tibetan monastery,the latter leads let meto the briefly observation War that Turing made several vital contri- es of those in charge of a discipline 1.at Introduction COURT URING PHOTO unlikely and heartening. summarize the computer-relatedmany Intexts this contain Viewpoint, highflaws. I comparebutions asand part of the British team try- - T have their own unique narrative thrust, In Augusta given moment 1965, Anthony in a given place. Oettinger Each and the rest- of the Program Committee of the ACM I will discuss Hodges’s 1983 biography 36 COMMUNICATIONS OF THE ACM | JANUARY 2014 | VOL. 57 | NO. 1 contrastname some that key gets arguments integrated put forth into an of metficialized andby three proposed genealogy Turing scholars—Andrewthat is the anresult annual of dis ‘National Lecture- be called the Allen [sic] M. Turing cussionsHodges,1 and negotiations,Martin Davis, and of politicsJack Co The Universal Computer: Lecture’. peland—highlightingThe decision the was conceptual also made that the ACM shouldinvariant have meaning.Computability an awards and Unsolvability program. and propaganda. Historical Reflections col difference between a “universal7 Tur - - sented a modern definition in his 1958 The ACM Awardsing machine” Committee and a “stored was program” formed in November 1965 (Associationbook of Computing giesMachinery Toof physicsthe general and1966a public,mathematicscomputer.). the After Mygenealo arefindings having complement collected - information on the awardand a procedures definition for the ‘in layman other in his Thomas Haigh’s January 2014 recent book probably more familiar than that of prints The Road from Leibniz to Turing computerprofessional science. Forsocieties’, physicsmunications we go Lewis Clapp—chairman- of the). ForACM ¼exam Awards Committee—wrote in umn, “Actually, Turing Did Not Invent ¼ definitions I abide with here and with from Galileo via Newton to Einstein. August 1966 that the Computer.”In his 1936 paper, “On Computable - which modern textbooks in computer For mathematics we begin with Euclid and scienceThe comply. meaning attached to the words - π and progress over Descartes,[a]n awards Leibniz, programNumbers,” [ Turing]wouldbeafittingactivityfortheAssociationasit introduced his au - - NO. 10 Euler and Gauss up to Hilbert. Com tomatic··· machines, which do not con “stored program”| also changed in the post-war years and it is unlikely those puter science by contrast enhancesis a relatively its own imagetain asa finite a professional output (nor an input) society. as is [ ][I]twouldservetoaccentuate- the case with the later-devised “Turing ··· young discipline. Nevertheless,new it software is techniques and theoretical