Introduction to the proceedings of the J.R. Abrial conference, a pioneer in the scientific development of computer languages ​​and formal methods and their large-scale application in industry, Nantes, May 27, 2025

 

 Introduction
Henri Habrias
henri.habrias@univ-nantes.fr

The last thing you find when writing a book is knowing
which one to put first.

Blaise Pascal, Discourse on the Passions of Love

My first computer science books were Meyer and Baudoin's Programming Methods, Mickaël Jackson's books, Jean-Dominique Warnier's books, and Delobel Adiba's Databases and Relational Systems. I quickly supplemented these with those by Tony Hoare (CSP) and Robin Milner (CCS), whose teaching methods I appreciated. At that time, I was doing what was called "method integration," in addition to "methodology," the study of methods (1), a term that was used in the timetable when I arrived at the IUT of Nantes. Naive set theory—which I didn't experience in high school—(2) was implemented in Warnier's LCP. When I introduced it to some colleagues trained in computer science, the reception wasn't warm. J.R. Abrial recounts the same thing in his lecture at the Collège de France. Fortunately, I had a colleague with a mathematical background who appreciated it. I supplemented my bibliography with J.R. Abrial's article "Data Semantics," published in the proceedings of the Cargèse conference. Unavailable on the web, and in libraries (except one!), we reproduce it in this document, along with the first publication on Z, which appeared in Meyer and Baudoin, which Bertrand Meyer authorized us to reproduce.
This is how I followed J.R. Abrial's writings for decades. I benefited from his writings before publication (3). He addressed my programming topics with what was not yet B. (4). And in 1998, he agreed to come and record his course on B in Nantes in a studio in front of a group of students. These VHS cassettes were used to teach B in several institutions in France and around the world.
With B, I rediscovered trains. My first dissertation in 1969 was entitled "City Deficit and Fare Options in the Railway." With Abrial, I had the ideal teacher for my self-study in computer science and applications that I liked.
One day, a British colleague, Bill Stoddart, from Teesside University, was tasked with establishing relationships with French universities. He was teaching Z, which I also taught, after having taught VDM and the Metoo language. So Bill came to Nantes. This provided an opportunity for long exchanges with Bill, Steve Dunne, and Andy Galloway, and courses as part of the Erasmus program with students from various institutions across Europe. The discussions continued with B.
The team, which we will call "Teesside Truant School," presented an article entitled Much Ado About Nothing on the use of bunch theory in B, and brought us back to VDM. I would have loved a dialogue like the one between Raymond Devos (5) and Claude Hagège during the Apostrophes program on December 6, 1985.

In 1995, I organized the international Z2B conference, then the following year the first conference on B, on the occasion of the release of the B-Book. J.R. Abrial presented a talk there, "Extending B without Changing It," in which he introduced what would become event-based B. We reproduce this article in this document. On the occasion of this conference, I created the ACPB association, the Association for the Piloting of International Conferences B, whose current president is Dominique Méry. Since then, the conference has continued as part of the ABZ conferences. This year marks the twenty-fifth anniversary of the first conference.
Dominique Méry presents "Teaching Formal Techniques with Event-B and Rodin" and the entire history of his teaching and research. While preparing for this conference, we were able to observe that so-called "digital" memory (why not "alpha-numeric?") fades more easily than that on paper. Many documents are impossible to find today. (6)
Regarding the LTR (Real Time Language) language, we were unable to find our contacts at the Arsenal d'Indret, who practiced LTR and Socrate (then Clio). We thank Didier Andreu (10) who sent us his courses on LTR. A week before the conference, Pascal Poizat, a former student at Nantes, pointed out a report from the Assembly National speaking about LTR. In a few days we had discussions with former members of the Navy Programming Center. And finally with Gérard Le Lann who knew J.-R. Abrial at the CPM and continued to exchange with him. At the first conference in Nantes, Gilles Kahn spoke to us about the Ariane rocket accident. Thirty years later, Gérard Le Lann quotes his INRIA report which contradicts the report of the BEA (Accident Investigation Bureau), chaired by G. Khan. (11). In a master's program in the history of science at the François Viète Center in Nantes, we were told in 2008-09 that in 20 years we would be wondering what caused a gap in the documentation! 5,000 / 5,000
It should be noted that our British colleagues have published a number of texts available on the history of computing in the UK. We often cite them in this document. This is much rarer in France, where we still do not have a computer museum, despite the efforts of the Aconit association (7) in Grenoble, which is engaged in information and preservation work.
Fortunately, in Grenoble, Jean-Pierre Giraudin had documentation on the Socrate DBMS and on the "Z of Grenoble." And he had just participated in the writing, with Michel Adiba, of a book on the history of computing in Grenoble. (8) We also benefited from Jean Ricordeau's thesis. (9)

We have not cited everything that has been published on Z and B. A bibliography can be found here. (12) , but we have compiled a very long chronological bibliography with citations that allows us to place J.R. Abrial's publications in time, in and around them. Using a simple example, "A door is open or closed," we present B, Event-B, and Z, and their differences.
In April 2015, J.R. Abrial was invited to give a lecture at the Collège de France and recounted the story of "a monomaniacal researcher" who wanted to answer the question "How do you know if what you're programming is what you intended?" We have produced a partial transcription, mainly based on his work with the RATP (Paris Regional Transport Network), supplemented both upstream and downstream, primarily by the work of Abrial, who was most often an "independent consultant" at Rue des Plantes in Paris, then in Marseille.
"Industrial" applications are a hallmark of J.R. Abrial's work. Fernando Mejia agreed to include his foreword to the book "Formal Specification with B" (13) in this document. Thierry Lecomte (Clearsy) and Frédéric Badeau (Systerel) contributed to this story. I also remember that Clearsy sent us Atelier B for free, which allowed us to set up practical work for our students... and to participate in discussions on the BUG (B User Group) forum. I'm thinking of Ranan Fraer (14), who helped out many of us. I discovered at the EDF, CEA, and INRIA School in Bréau-Sans-Nappe in 1995, where Ranan spent his nights on Atelier B, that he answered questions from users of the workshop without having had it in his hands! A marvel of mathematics!
Guy Lafitte, who was an engineer at INSEE, stationed in Paris and then in Nantes, is thanked by J.R. Abrial for his contributions. Guy applied B during the population census (15). Retired, he continues his debate on published algorithms (3) or invents new ones. Here, he talks about the pile of clothes, which will resonate with everyone, in a world where we don't throw away an item of clothing or a sheet that has only been used once.
The development of B was also partly carried out through projects. We provide a history of these. One led to the Rodin platform https://wiki.event-b.org/index.php/Rodin_Platform_Releases.
Nowadays, "UML notation" is in all teaching programs. Before it, we saw the arrival of many notations to express what was found in Data Semantics (16). We even had a notation that used symbols when there were no constraints. Something new was needed! Imagine driving on a road where what is allowed is indicated, not what is forbidden. A notation that is not that of a country of freedom. We taught a notation, that of the "binary relational model" (17), introduced by Nijssen. It allowed the expression of set constraints, and for relations used only two symbols: totality (the universal quantifier) ​​and uniqueness (functions). Moreover, it allowed sentences to be expressed in the form of subject, verb, complement. The notation of Z and B is not an application of Occam's razor. So we propose our notation, which we will call Oc. We deny neither its roots nor its accent. But we have seen the various proposals for ergonomic keyboards. They were not successful. We are still using AZERTY and QWERTY, which is less of a problem these days because we carry our own computer. Time digs furrows, but sometimes fills them. I don't foresee success for this notation.
Managing to read old CDs, we found an unpublished article entitled "Pencils and Colors." We updated it by giving it a less childish title: "Set Ontology with B." Readers of the bibliography will find illustrations of unusual entries in a software engineering bibliography. This will be our interpretation of Philippe Ramette's statue "Éloge du pas de côté" (In Praise of the Sidestep) that participants will see on Place du Bouffay in Nantes.

You don't have "mixtures" before you. These are not what English speakers call Essays in Honor of or A Tribute to. This is not a history thesis.of science and technology on software development. We haven't found any that have been supported in France. The topic isn't "promising."

Let's just say it's a Blog!

Some will note that J.R. Abrial began working on "real time" at the French Navy Programming Center, then in the field of databases and "state-based" modeling, with, as he says in his lecture at the Collège de France, a monomania: specifying and proving development before writing the program. For years, he neglected the "event-driven" aspect. Then he returned to it with Event-B. And during his lecture at the Collège de France, he introduced us to "hybrid systems," invited by Gérard Berry, whom he knew from his early days in the 1970s, who has just published "Le temps autrement" (18).
The historian will certainly produce "some meaning" from it.

We thank Jean-Raymond Abrial, whose approach, teaching methods, and publications have motivated many academics and practitioners around the world.
Jonathan Bowen wrote that Ib Holm Sorensen (19), who worked with J.R. Abrial at Oxford, was a "doer" (20). Two "doers" shared the same office at Oxford.
In 1995, the From Z to B conference was held in the amphitheater of the Dobrée Museum in Nantes, followed the following year by the First B International Conference.

That was thirty years ago!

Acknowledgments
We thank Pascal André, lecturer and HDR at Nantes University, and the Laboratoire des Sciences du Numérique de Nantes (LS2N). Without them, this conference would not have been possible.

Marc Guyomard, former professor at ENSSAT in Lannion, and Pascal André made the proceedings possible.

We thank Nantes University for once again making it possible to discuss B at the Nantes Convention Center. The last two times were also during the Journées Scientifiques (JS), in 2008 and 2013, with the conference series "The B Method, from Research to Teaching." J.R. Abrial was the guest speaker at the first JS, in 2008.
And all those who provided us with documentation, scanned documents, and authorized the reproduction of texts. And let's not forget all our correspondents who responded promptly.
Finally, thank you to Nicole, who didn't think my office would return to its former appearance.

1. The term methodology is used instead of "method"; it sounds more pleasing to the ear! 2. The textbooks of the time, apart from the books intended for mothers and fathers (!), were more difficult to read than the Historical Note and the results booklet in the volume La théorie des ensembles, Chapitres 1 à 4, N. Bourbaki, Eléments de mathématiques, Masson, 1990
3. J.R. Abrial, A small study in program design, Nov. 1986, unpublished, A formal introduction to abstract machines, May 4, 1987, Abstracts machines, 1988
4. H. Habrias, Le cas des élections à la proportionelle en LCP, Programming déductive, Méthode de J.R. Abrial. Let us recall that the only French legislative election with proportional representation under the Fifth Republic took place on March 16, 1986, under F. Mitterrand. 
5. "And if you yourselves, ladies and gentlemen, have nothing to say, well, we'll talk about it, we'll discuss it! I'm not an enemy of the symposium.
But, you might ask, if we talk for the sake of saying nothing, what are we going to talk about?
Well, nothing! Nothing!
Because nothing... isn't nothing.
The proof is that we can subtract it.
Nothing minus nothing = less than nothing!
If we can find less than nothing, it's because nothing is already worth something!
We can buy something with nothing!
By multiplying it,
One times nothing... is nothing.
Twice nothing... isn't much!
But three times nothing! For three times nothing, we can already buy something... and for cheap!
Now, if you multiply three times nothing by three times nothing:
Nothing multiplied by nothing = nothing.
Three multiplied by three = nine.
That's nothing new!" 
6. This is the case of the TSI journal and its article: J.R. Abrial, Specify or How to Master the Abstract, Vol. 3, No. 3, pp. 201-319, 1984.
10. Former lecturer and researcher at the University of Montpellier II, now co-founder, head of the technology section, and general manager of the company Neurinov https://neurinnov.com/, which has agreed to publish its course, exam questions, and practical work. 11. https://www.rocq.inria.fr/novaltis/research_reports/RR-3079.pdf The Ariane 5
Flight 501 Failure - A Case Study in System Engineering for Computing Systems
12. https://www.atelierb.eu/methode-formelle/bibliographie/
13. H. Habrias et al., Hermès Lavoisier, 2001
14. https://www-sop.inria.fr/croap/personnel/Ranan.Fraer.html
15. Guy Laffitte, Pascal Bernard, The French Population Census for 1990, ZUM95, 9th 16. J.R. Abrial, Data Semantics in Data Base Management, Klimbie, Kofeman, eds, North-Holland, 1974, pp. 1-59
17. H. Habrias, The binary relational model,méthode IA,(NIAM), Eyrolles, 1988
18. Gérard Berry, Le temps autrement, Odile Jacob,2025
19. Ibn Holm Søorensen : Ten Years After, Jonathan Bowen, FACS FACTS Issue 2022-2 July 2022 20. "Le nom doer (prononcé doueur) est bien ancré en anglais ; il désigne une personnequi agit pour affronter un problème, et s'oppose au thinker, qui resterait, lui, au stade de la réflexion. Cette opposition entre ces deux attitudes est très ancienne ; ainsi, dans son Bellum Jugurthinum, Salluste loue Jugurtha de réussir à les concilier : Ac sane, quod dicillumum in primis est, et proelio strenuus erat et bonus consilio (" Et de fait, il réunissait les deux qualités les plus diffciles à concilier, la bravoure au combat et la sagesse au conseil "). Si le français n'a pas un substantif équivalent à doer, alors que " penseur " traduit fort bien thinker, il a à sa disposition de nombreuses formes verbales, comme " ceux qui agissent, qui font, qui réalisent, qui sont dans l'action ", ou nominales, comme " hommes d'action "."
https://www.academie-francaise.fr/doer