Archive for March 2023

“Object Success” now available

A full, free online version of Object Success
(1995)

success_cover

 

I am continuing the process of releasing some of my earlier books. Already available: Introduction to the Theory of Programming Languages (see here) and Object-Oriented Software Construction, 2nd edition (see here). The latest addition is Object Success, a book that introduced object technology to managers and more generally emphasized the management and organizational consequences of OO ideas.

The text (3.3 MB) is available here for download.

Copyright notice: The text is not in the public domain. It is copyrighted material (© Bertrand Meyer, 1995, 2023), made available free of charge on the Web for the convenience of readers, with the permission of the original publisher (Prentice Hall, now Pearson Education, Inc.). You are not permitted to copy it or redistribute it. Please refer others to the present version at bertrandmeyer.com/success.

(Please do not bookmark or share the above download link as it may change, but use the present page: https:/bertrandmeyer.com/success.) The text is republished identically, with minor reformatting and addition of some color. (There is only one actual change, a mention of the evolution of hardware resources, on page 136, plus a reference to a later book added to a bibliography section on page 103.) This electronic version is fully hyperlinked: clicking entries in the table of contents and index, and any element in dark red such as the page number above, will take you to the corresponding place in the text.

The book is a presentation of object technology for managers and a discussion of management issues of modern projects. While it is almost three decades old and inevitably contains some observations that will sound naïve  by today’s standards, I feel  it retains some of its value. Note in particular:

  • The introduction of a number of principles that went radically against conventional software engineering wisdom and were later included in agile methods. See Agile! The Good, the Hype and the Ugly, Springer, 2014, book page at agile.ethz.ch.
  • As an important example, the emphasis on the primacy of code. Numerous occurrences of the argument throughout the text. (Also, warnings about over-emphasizing analysis, design and other products, although unlike “lean development” the text definitely does not consider them to be “waste”. See the “bubbles and arrows of outrageous fortune”, page 80.)
  • In the same vein, the emphasis on incremental development.
  • Yet another agile-before-agile principle: Less-Is-More principle (in “CRISIS REMEDY”, page 133).
  • An analysis of the role of managers (chapters 7 to 9) which remains largely applicable, and I believe more realistic than the agile literature’s reductionist view of managers.
  • A systematic analysis of what “prototyping” means for software (chapter 4), distinguishing between desirable and less good forms.
  • Advice on how to salvage projects undergoing difficulties or crises (chapters 7 and 9).
  • A concise exposition of OO concepts (chapter 1 and appendix).
  • A systematic discussion of software lifecycle models (chapter 3), including the “cluster model”. See new developments on this topic in my recent “Handbook of Requirements and Business Analysis”, Springer, 2022, book page at bertrandmeyer.com/requirements.
  • More generally, important principles from which managers (and developers) can benefit today just as much as at the time of publication.

The download link again (3.3 MB): here it is.

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The mathematics of the seven messengers

In my previous article I referred to the short story The Seven Messengers by Dino Buzzati, of which I have written a translation. Here is a quantitative analysis. I will also refer the reader to a very nice article published in 2009 on this topic: The Seven Messengers and the “Buzzati Sequence” by Giorgio D’Abramo from the National Institute of Astrophysics in Rome. It is available here on arXiv. I discovered ita few years ago after working out my own “sequence” and had a short and pleasant correspondence with Dr. D’Abramo. You can compare our respective derivations, which I think are equivalent. Here is mine.

Although Buzzati gives absolute values (40 leagues per day), all that matters is the ratio m between the messengers’ and caravan’s speeds (m > 1). The relevant measures of time are:

  • The messenger-day, which take as unit of time.
  • The caravan-day, which is m times a messenger-day.

If as unit of distance we take ground covered in one day by a messenger, then time is equal to distance.

So if Tn is the time when a messenger rejoins the caravan after his n-th trip back home, we have

Tn + Tn+1  = m (Tn+1 – Tn)                  [1]

Justification of [1]:  both sides measure the time from when the messenger leaves (for the n-th time) to when he next rejoins the caravan. Note that the messenger goes back for his n+1-st trip on the very day he completes the n-th one.  On the left we have the time/distance  covered by the messenger (Tn to go home, plus Tn+1 to catch up). On the right, Tn+1 – Tn is the time/distance covered by the caravan in caravan units, which we multiply by m to get messenger-days.

The equality can be rewritten

Tn+1 = (m + 1) / (m – 1) Tn

yielding a geometric progression

 Tn = Kn T0                  [2]

where T0 is when the messenger leaves for his first trip, and the constant K is (m + 1) / (m – 1).

The Prince, who is as bad at horses as he (unlike Buzzati) is at math, had initially expected m = 2. Then K is 3 / 1, that is to say, 3. In that case the progression [2] would have been Tn = 3n T0. Even then, he would have found the result disappointing: while the first messenger returns the first time after three days, the third messenger, for example, returns the fifth time after about almost 1000 days (35 is 243, to be multiplied by 4), i.e. close to a year, and the last messenger returns for the sixth time after 16 years ( 36 × 8 /365).

The way things actually happen in the the story, the Prince determines after a while that m = 3/2 (the messengers go faster by half than the caravan), so K is 5. (In the text: Soon enough, I realized that it sufficed to multiply by five the number of days passed so far to know when the messenger would be back with us.) The unit travel times (Kn) of messengers are as follows, giving return times if multiplied by two for the first messenger (since he first leaves on the second day), three for the second messenger) and so on:

 

(1)          5 days: as stated in the story, the first return is after 10 days for Alexander, 15 for Bartholomew, 20 for Cameron…

(2)          25 days: Alexander returns for the second time after almost one month.

(3)          4 months

(4)          Close to two years (20 months)

(5)          8 years and a half

(6)          43 years

(7)          214 years

(8)          Millennium

Buzzati was a journalist by trade; I do not know what mathematical education he had, but find his ingenuity and mastery impressive.

(By the way, there might be a good programming exercise here, with a graphical interface showing the caravan and the messengers going about their (opposite) business, and controls to vary the parameters and see what happens.)

Another point on which the Prince is delusional is his suspicion that he would have fared better by selecting more than 7 messengers, a number he now finds “ridiculously low”. It would have cost him more money but not helped him much, since the number of messengers only affects the initial value in the geometric progression: T0 in [2]. What truly matters is the exponential multiplier Kn, where the constant K  — defined as (m + 1) / (m – 1) — is always greater than 1, inexorably making the Tn values take off to dazzling heights by the law of compound interest  (the delight of investors and curse of borrowers).

Obviously, as m goes to infinity that constant K = (m + 1) / (m – 1)  approaches its limit 1. Concretely, what messenger speed would it take for the Prince’s scheme to work to his satisfaction? The story indicates that the caravan covers 40 leagues a day; that is about 160 kilometers (see here). Ambitious but feasible (8 hours a day excluding the inevitable stops, horses on trot); in any case, I would trust Buzzati, not just because people in the 1930s had a much more direct informal understanding of horse-based travel than we do, but mostly because of his own incredible attention to details. So they are going at about 20 kilometers per hour. Now assume that for the messengers, instead of horses that only go 50% faster than the caravan, he has secured a small fleet of Cessna-style individual planes. They might fly at 180 km/h. That’s m = 9, nine times faster. Hence now K = 10 / 8 = 1.25. So we only lose 25% on each return trip; planes or no planes, the law of compound interest takes its revenge on the prince all the same, only a bit later.

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The Seven Messengers

A number of years ago I discovered the short stories of the Italian writer Dino Buzzati (most famous for his novel translated as The Desert of the Tartars). They have a unique haunting quality, for which the only equivalent which I can summon is Mahler’s Des Knaben Wunderhorn or perhaps the last variation of the Tema Con Variazoni in Mozart’s Gran Partita. I was particularly fascinated by the first one, I Sette Messaggeri (The Seven Messengers) in a collection entitled La Boutique del Mistero (The Mystery Boutique, Mondadori, first published in 1968 although I have a later softcover edition). I resolved to translate it. I completed the translation only now. It starts like this:

Day after day, having set out to explore my father’s realm, I am moving further away from the city, and the dispatches that reach me become ever more infrequent.

I began the journey not long after my thirtieth birthday and more than eight years have since passed; to be exact, eight years, six months and fifteen days of unceasing travel. I believed, when I departed, that within a few weeks I would easily have reached the confines of the kingdom, but instead I have continued to encounter new people and new lands, and, everywhere, men who spoke my own language and claimed to be my subjects.

At times I think that my geographer’s compass has gone awry and that while always believing to be heading south we may in reality have gone into circles, stepping back into our tracks without increasing the distance from the capital city; such might be the reason why we have not yet reached the outer frontier.

More often, though, I am tormented by a suspicion that the frontier may not exist, that the realm spreads out without any limit whatsoever, and that no matter how far I advance I will never arrive at its end. I set off on my journey when I was already past thirty years old, too late perhaps. My friends, and even my family, were mocking my project as a pointless sacrifice of the best years of my life. In truth, few of my faithful followers consented to leave with me. Insouciant as I was – so much more than now! – I was anxious to maintain communication, during the journey, with those dear to me, and among the knights in my escort I chose the seven best ones to serve as my messengers.

I believed, without having given it more thought, that seven would be more than enough. With the passing of time I have realized that this number was, to the contrary, ridiculously low; this even though none among them has fallen ill, or run into bandits, or exhausted his mounts. All seven have served with a tenacity and a devotion that I will find it hard ever to recompense.

To distinguish more easily between them, I assigned them names with initial letters in alphabetical order: Alexander, Bartholomew, Cameron, Dominic, Emilian, Frederic, Gregory.

Not being used to straying so far away from my home, I dispatched the first, Alexander, at the end of the second evening of our journey, when we had already traveled some eighty leagues. The next evening, to ensure the continuity of communications, I sent out the second one, then […]

That is only the beginning. The full text appears here but it is password-protected. Here is why: in 2010 I managed to locate the right holders and wrote to them asking for permission to publish an English translation and put it on the web. I received a polite, negative answer. So I gave up. Browsing around more recently, though, I found two freely available translations on the Web. (I also found the original Italian text here, although with a few differences from the published version.) All for the better, you would say, except that one of the translations is in my opinion awful and the other not that much better. Buzzati is a stylist in the tradition of Flaubert, in whose texts you quickly notice (especially when translating) that every word is exactly the right one, the only possible one, at the only possible place in the only possible sentence. You cannot translate a Buzzati story as you would an article in today’s paper. You have at least to try to respect the music of the text. So I completed my own attempt after all, but I still don’t want to violate anyone’s copyright. (Perhaps I am being silly.) In any case, though, I can certainly publish a fair-use extract as above and use the text for myself and my colleagues and friends. So if you want access just ask me.

One unique feature of the Seven Messengers is that it is a geek’s delight: it is actually based on a mathematical series. I wrote an analysis of the underlying math, but to avoid spoiling your pleasure if you want to look at it by yourself first I put it in a separate entry of this blog. Click here only if you do want the spoiler.

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Macron and Borne: profiles in courage

The French president, Emmanuel Macron, and prime minister, Elizabeth Borne, are showing incredible political courage in promoting an indispensable reform of the pension system. The international press (with the exception of one recent reasonable Washington Post editorial) has largely taken the side of the strikers, explaining sententiously that the proper answer would be to tax companies more (as to the efficiency of that approach, here is an old but still valid example, from a left-wing paper). The unions have vowed, in the words of one of their leaders, to “bring the country to its knees” and seem intent on reaching this goal literally. (It may be useful  to point out that unions in France are not what the term suggests. In other countries a union represents the workers at a company or administration. In France every organization has several unions, usually 4 or 5, competing for, typically, a small minority of the workers, but with a role enshrined in the constitution. They are really state-supported political organizations, of various political hues, several of them openly hostile to employers and to capitalism. Interesting approach.)

The reform of the pension system was part of Macron’s electoral program and has been amended repeatedly to take into account the special characteristics of manual or otherwise difficult worth. Months of attempted negotiations took place with those union representatives who were willing to talk. The extreme left and extreme right were united to defeat the reform and at the last minute, after innumerable debates in Parliament which had resulted in a majority-backed solution, intimated enough moderate-right deputies to force the government to use a special constitutional mechanism (“article 49-3”) to ram it through. Who knows how many disruptions of basic services the country will have to endure in the coming months as saboteurs of various kinds try to make good on their promise to prevent the country from functioning. The attitude of the international bien-pensant press, who fans the flames (as they did with the Gilets Jaunes protests 5 years ago),  while castigating the January 6 Washington rioters, who are of the same ilk, is unconscionable.

The entire political class knows that a reform is indispensable, and has been delayed far too long, out of the cowardice of previous governments. Macron’s and Borne’s goal is simple: to preserve France’s pension system (the very system that the opponents deceitfully accuse them of destroying), based on solidarity between generations, workers paying for retirees, as opposed to a capitalization-based system with its dependence on the ups and downs of the stock market. Thanks in particular to a generous health service, people live ever longer; the new plan makes them work a couple of years more to help ensure the sustainability of the approach. Macron is in his second, non-renewable term and has decided that he would not leave office without having carried out this part of his duty. Borne, an outstanding manager with a distinguished record, has taken the risk of sacrificing her political career by bringing the reform through. (In the Fifth Republic’s mixed presidential system, the conventional wisdom is that the prime minister is the president’s “fuse”, an expendable resource for implementing difficult tasks. Cynical and tough, but a direct consequence of the constitution designed by De Gaulle and his deputy Debré 60 years ago.)

In the meantime, Macron and Borne are showing Europe and the world what true dedication and leadership mean.

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Le courage de Macron

(An English variant will appear tomorrow.)

La presse nationale et internationale est déchaînée contre Borne et Macron. Les extrémistes et factieux de tous bords jurent de “mettre le pays par terre” (comment, au passage, peut-on accepter ce genre de langage de la part d’un responsable “syndical”?).

Toute la classe politique sait bien sûr que la réforme est indispensable. Elle est le seul moyen de protéger le système français de retraites par répartition. Elle tient compte de la pénibilité des travaux. Elle remet la France au niveau des pays voisins. Elle est le bon sens même. Elle suit des années de tergiversation de la part des gouvernements précédents effarouchés, et des mois de consultation avec les “partenaires sociaux”, si l’on peut parler de concertation pour une tentative de dialogue avec des gens qui ne cherchent que le tintamarre politique.

Quel courage, quelle détermination chez le président et la première ministre, qui au milieu des insultes sacrifient leur intérêt personnel au bien public. Les émeutiers — dans la tradition des ligues des années trente, des gilets jaunes, des voyous du 6 janvier 2021 à Washington — essayent de les faire reculer par la force, mais la raison et le droit triompheront.

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