EWD 547

Tripreport E.W.Dijkstra, England and USA, 3 - 26 January 1976.

This time the hardships of travel started weeks before the date of departure, viz. when I tried to order my ticket. On my previous visit of nearly three weeks it had been pointed out that I would have enjoyed a cheaper rate if I had extended my visit with a few days. At that occasion IBM was paying my ticket, so I did not mind, but this time I was travelling at Burroughs' expense. Therefore I inquired about the conditions for the cheaper fare: did it mean 22 days in the USA or 22 days away from home? Burroughs' (new) travel agent told me that the condition was 22 days away from home. With the intention of saving money I extended my trip at the front end with a short visit to England (at the other side of the trip was impossible, for on Tuesday the 27th of January I had to be back at the University). When all was arranged, the travel agency discovered not only that it had given me the wrong information —the fare reduction was now not applicable— but also that with my schedule it did not know how to compute the price, the reason why they phoned me with the urgent request to change my itinerary! In the meantime I was so exasperated that I had no difficulty in resisting to that pressure. The reason for the exasperation was that I had ordered my ticket in the first half of December with the intention of having it in my possession before Christmas: it is always nice not to have to rely upon postal delivery between Christmas and New Year. But in spite of my efforts, this nervous traveller passed the days of Christmas without his ticket.... (After my arrival in the USA I learned that this, however, was not fully the fault of the Dutch travel agency, which had been waiting for the confirmation of an internal flight which did not come through because the America airline reservation information processing system had been inundated by additional transactions resulting from the strike at United Airlines.) I received my ticket —with the flight Chicago-Detroit unconfirmed— just in time.

The other narrow escape was my visa. Some months ago I had tried to have the expiring validity of my passport extended, but because it was already so full of stamps, the Dutch authorities refused to do so and they gave me a new passport. Because my old passport contained an indefinitely valid American visa, it was returned to me with a corner cut from all pages except the one containing my American visa. In addition the new passport contained a note, saying that the old one was to be regarded as an extension. I was given to understand that I could travel with the two passports together and decided to postpone the transfer of the American visa until I would be in Rotterdam anyway. Friday at noon, the day before my departure, this nervous traveller was checking everything, tickets, money, passport, and suddenly I thought: "Let me check that story about the two passports with the American Consulate." So I made a telephone call and was told that a visa in an old passport was not valid, but that they were open and ready to serve me until four o'clock! While collecting my papers I shouted to my wife to get the car keys so that she could take me to the railway station! I made it.....

On the way back from Rotterdam to Eindhoven, trains were not running according to schedule: the storm had started that during that night would reach strength 11 at the scale of Beaufort. Saturday morning we switched on the news, and what we heard was sufficiently alarming to take an earlier train and took me without delay to Amsterdam. Occasionally I saw a fallen tree, an overturned vehicle, and so on, but approaching Amsterdam I saw a plane in the air, and that was reassuring. The driver of the coach from Amsterdam Central Station to Schiphol Airport had some difficulties in keeping his vehicle in lane —it swayed like a drunkard— but that was all. According to schedule I left Schiphol at 12.05 and arrived at Heathrow also at 12.05, thus absorbing the first hour of the time shift. (When I boarded the British Airways plane, the steward offered me an English newspaper; after a glance at the headlines I said "No thank you. The news looks rather depressing." Answered the steward: "Ah... Wait until you arrived there!" A grim welcome...)

Mike Woodger was at the airport to pick me up, and I had a pleasant weekend with him. He helped me by providing me with the English vocabulary that I needed for the description of a few theorems and proofs in Euclidean geometry. On Sunday morning —this is a tradition— we went for a walk through the beautiful Surrey countryside, but this time we kept it short, for rain had made the path very muddy. On Sunday evening a young logician and his wife joined us for dinner; of the conversation thereafter I remember that English poetry was a main subject, Mike's wife going upstairs to fetch an anthology that was needed to settle a dispute.

On Monday morning Mike and I left early for the National Physical Laboratory where I was expected to give a lecture. As I was due at the airport at 11.15 for my flight to Chicago I did not have much time and, in order to speed up the presentation, I prepared the blackboard beforehand. At 9.30 I started, at 10.30 I had covered all the intended material and after fifteen minutes discussion —it was a pity that I had not more time, for the discussion was certainly not finished— I was taken to Heathrow, where Mike dropped me at the doorsteps of the appropriate terminal at 11.14.

The queues at the TWA desks were very long and very slow, and I heard my flight being announced before I had checked in: "...is now boarding at gate so and so." Luckily it was a Boeing 747, for which "boarding" is a long-drawn affair, and I made it, praying that my luggage would make it as well. When we were expected to depart, the captain announced that one of the passengers, who had checked in, had not turned up and that, in order to exclude a bomb in the luggage department, we had to identify our luggage. All trunks and suitcases were unloaded, and the passengers had to come out in groups in order to identify their own baggage. The jumbo being fully loaded, the whole operation took two hours. For once I crossed the Atlantic with the comforting certainty that my suitcase was indeed crossing it with me in the same plane!

I was not worried at all about catching my connection in Chicago. As that was the first flight I had been unable to get confirmed I had already arranged with Dave Dahm who had offered to collect me at the Detroit Airport, that I would call him from Chicago, as soon as I knew by which flight I would arrive. The flight from Chicago to Detroit was no problem at all, at the gate they knew my name and there were enough seats. The only problem was making my first call from an American telephone booth. It was a frightening experience: to discover how to operate such equipment in "unfriendly Chicago" is no trivial matter. Eventually I succeeded and then discovered that, in the course of the proceedings —and, as far as I am concerned, this is also tradition at O'Hare— I had lost my briefcase. I retrieved it by retracing my steps. At 21.14 (their time!) Dave collected me —at least the remains— at the gate in Detroit and took me to the Southfield Holiday Inn, where I should stay for the next four nights.

My room (in "the tower") was icy cold, so I switched on the heating equipment to the best of my knowledge —the instructions were very confusing— and went downstairs, where I ordered what felt I needed: a large glass of cold milk ($1.05 ! I was shocked.). After sipping it up, I returned to my room in the tower, in which the supposed heating equipment was causing a polar storm. I switched off the fan, gave the ambiguous instructions another interpretation and went to bed with the best of possible hopes. After half an hour under the blanket I was so cold, that I put on my clothes again, packed my suitcase and went to the reception to ask for another room. The girl at the desk asked me whether I would accept a room on the ground floor. I explained that I did not care about the place of the room, but about its being warm enough. She then explained her question "All through the tower we have trouble with the heating system." My conclusion was that it was a new hotel, erected by a dumb architect, and I fell asleep, doubting the wisdom of the Holiday Inn Company to try to operate this hotel under these circumstances.

The next morning I was a free man: Dave had offered to leave me alone until lunch, so that I could recover from the trip. I recovered that morning as well as I could. Thinking about last night's experience I concluded that even if the heating equipment itself were OK, it would cause trouble on account of the poorly written instructions, and in an effort to make myself useful and to kill the time, I decided to go to the desk, to ask for the documentation so that I could discover how it should be operated, and then to rewrite the instructions. (I was reminded of the elevator in the new main building of the Technological University Eindhoven, whose instructions for use made sense only after the third effort! Not only English, but also Dutch is difficult....) At the desk I was informed that they had no documentation, but that my effort was not needed either, because the equipment was so lousy anyhow that it would be replaced by something better at the earliest possible occasion.

Tuesday afternoon was my only visit to Burroughs World Headquarters, and the various businesses I had to conduct there took the major part of it. The rest of the time was devoted to more technical discussions, while Dave brought me into the picture. It was quite instructive and I was grateful to him. I was relieved to see that he had to interrupt the conversation several times.... because he had difficulties into getting an ordered airline ticket physically into his possession! It is always comforting to observe that one is not the only sufferer....

The next two days I attended a symposium in generative software. Those were long days for someone who still suffered from the time shift and the cultural shock. Besides that it took me some time to realize that most speakers did not give a lecture, but gave a "presentation", and to realize what that difference meant. An additional difficulty for me was that most speakers came from the area of business applications and those people most definitely speak a special language. I had warned Dave beforehand that in this unfamiliar environment he should not expect any positive contributions from my side, and this he fully understood. I have restricted myself to trying to understand what was going on, in principle only asking for clarification when I really needed it. In some cases I am afraid that I made a nuisance of myself, e.g. when asking for more clarity than the speaker —or should I say: presentator?— could provide. One of them really drove me up the wall, when it turned out that his language was not only special, but also incredibly poor, poorer as a matter of fact than I had witnessed for a long time. He was such an unconscious user of words that he understood none of my requests for linguistical clarification —when I had to ask what was meant by the for me new word "to syntax", I was told that it was used in its normal meaning!— ; such questions were clearly beyond his mental horizon and on this one I gave up. The only consolation was that my exasperation caused considerable merriment among those who understood —and had perhaps expected— this clash of two worlds. The overwhelming impression those two days left was one of great diversity in many respects.

The next day I visited the Plymouth Plant. In the morning I gave a lecture for an audience of about twenty people. I talked about the same subject as Monday morning, but more at pleasure and in general detail. (It was nice not to be in such a hurry.) It was a very pleasant audience; after lunch we reconvened for a more general discussion, which started with that morning's topic but broadened as time went by, until I had to go to catch a late afternoon flight to Los Angeles. When leaving I realized that all questions had been pertinent and all remarks from the floor had made sense, and I was impressed. (After lunch someone pointed out that one of my proofs that morning had been done by handwaving. He was right. It was a very fresh result, up till that moment I had never done any better and I found myself challenged to supply the missing detail on the spot. After a few seconds panic on my side I thought that I saw how I could do it, and then proceeded to do it, as luck would have it to the full satisfaction of everybody present. Fun!)

On the flight to Los Angeles I started with EWD545, devoted to the topic of the two talks I had given that week; I stopped when the flight got a little bumpy. At Los Angeles —it was now 18.40, their time— Jack Mazola and John McClintock were waiting for me at the gate. After collecting my suitcase and having given them the opportunity to admire my featherweight luggage for a three week trip through different climates, we jumped into the car which, although it was two hours after sunset, was still warm inside. (In Detroit I had been woken up with "It is 7.15 and zero degrees outside." and, after looking outside, concluded correctly that the degrees were Fahrenheit and not Celsius; the next day I would see that "barely clothed" girls sunbathing on the beach!) On our way down South we had a dinner in a restaurant where our waitress most definitely did not like us, and then they took me to the hotel. My hosts had decided that "Sand and Surf" in Laguna Beach would be a much more pleasant hotel than the Mission Viejo Hilton Inn. I was very grateful for their choice: to have a hotel room with the Pacific right at your feet is really exciting!

I had the Saturday and the Sunday mostly for myself. I wrote a letter to my mother, a long letter to my wife, a sizeable entry in my diary and continued with EWD545. When I did not feel like writing —sometimes because my right hand got physically tired— I went for a little walk and looked around, or lay down on my bed and looked at the ceiling. For Saturday evening Jack had invited me for dinner, Sunday evening John took me to a harpsichord recital at Scripps College. To listen as a Dutchman in an American college to an Indian harpsichord player performing an English Suite from the German composer Bach who gave the movements French names, is fun. I did not like everything she played; when my thoughts wandered away from the music, I looked at the audience. It was a fascinating collection, such as only seats of learning can provide. Behind us sat an old lady, originally from Czechoslovakia; during the intermission I overheard her, bitterly complaining to an equally old gentleman, about the decline of the teaching of classical Greek in central Europe, in particular behind the Iron Curtain! She was really a delightful specimen...

Then came a week of hard work at the Mission Viejo Plant, where I went through two designs, through one even in great detail, giving my comments and asking questions as we went along. (The documentation had been sent to me in advance.) I did not identify "the million-dollar mistake" —that, of course, would have been the easiest and most spectacular way of earning my money— as both documents had been prepared very carefully. I could suggest some simplifications, issue some warnings. With respect to those two designs my main function has probably been confirming their hope that they worried about the right things. We have discussed a bus structure that might have advantages, a new form of redundancy in the representation of programs, and proving techniques for fine-grained interleaving, a subject about which we had been corresponding. And a number of minor topics; I learned something about pipelining. It was, as said, a week of hard work, but my impression was that it has been rewarding at both sides. A striking feature of the environment was the great respect with which people talked about both their superiors and their subordinates.

In a number of unexpected and unplanned ways this was a very instructive week. I happened to attend a few meals with Southern Californian businessmen. Some of them don't delete their expletives! I could hardly believe my ears! At a lunch a millionaire explained how to become one: it was instructive, he certainly added a few dimensions to my concept of "ruthlessness".

On Saturday I was again all on my own, and started with EWD546 on the bus structure; as I proceeded, the problem turned out to be harder than I had expected at first. On Sunday I had to go to La Jolla, and as Jack had promised a visit to the San Diego Zoo to his family, we all went there first. It was a beautiful day, and it is a beautiful Zoo, and I was grateful for the opportunity. Late in the afternoon I arrived at The Sea Lodge in La Jolla. The first thing that I missed was the radio: in Laguna Beach I had a radio in my hotel room and that had provided me with a great amount of good music, thanks to a station of the University of Southern California.

On Monday morning I was picked up by Don Lyle, who had promised to show me migrating whales. He had not been boasting: as soon as we approached the Pacific Ocean, he said "Look!" and pointed at a white puff! Later we saw porpoises, killer whales and a pelican. Fascinating. Monday and Tuesday I had a less tight schedule, during which various aspects of Don's project were discussed; the last three days of the week I gave a lecture series in The Sea Lodge for people from La Jolla, Mission Viejo, Pasadena and Santa Barbara. It was a little bit of a problem for me, that I did not know beforehand very well, to what extent my audience would be familiar with my writings. It turned out to vary among the participants. I have used the first two days as an introduction to my manuscripts, and as such I think they were successful. The last morning must have been a disappointment for some of them, as one or two asked for very concrete guidelines, more concrete than can be given. Essentially they asked "how to invent". On Friday at noon, the official performance was over and the ones that had far to go went home. I remained in the Sea Lodge with five or six people, talking about "seeds of complexity". (I was asked to do so, I had used the term in passing the previous day.) I got the impression that that was a very illuminating afternoon, perhaps the best of the whole three days.

Saturday, everything went wrong. Don Lyle and his wife picked me up with the intention of showing me the whales from a high point at the coast. But the whales had a free day. Then we went for lunch. In the first three restaurants that we tried, we had to wait so long, that we ended up at the "Gatekeeper" —if I remember correctly— where I offered them the lunch, but it was terrible. All the food they were serving was emphatically "healthy", but it was hard to find a dish without cheese. When I had found one —at last!— and ordered it, the waiter told me that the kitchen had run out of soup, so I had to choose again. And the salad —with oil and vinegar— had too much vinegar; but, presumably, it was very healthy. For the evening dinner I was taken to friends; they had asked whether I had objections to red pepper; and I had said "No", but they had not been warned about my abhorrence for cheese, and before my very eyes I saw my host ruining the dish.....

On Sunday, Don Lyle collected me at the hotel, and we had a number of pleasant and peaceful hours at his home, until they took me to the San Diego Airport, from where I had to leave for home, via Los Angeles. At 16.30 I took off and from that moment onwards I had again to take care of myself. At Los Angeles I had to change planes without a guardian angel from Burroughs at my side. I had plenty of time, I managed to do so quite successfully and a Lufthansa flight —fairly loaded— took me in a direct flight to Amsterdam. Monday evening at 18.30 I was home. The next day I had to go to the University, in order to grade students work at a written examination. It was terrible: the majority of the students don't know how to spell, nor how to write; nor how to program, for that matter. Being confronted with that junk was the greatest shock of the month.

*         *         *

Among the papers I saw since my return was a report concerned with the Dutch government funding of mathematical research. It pointed out that the usual planning techniques, in spite of being usual, might be totally inadequate because the unit "a manmonth" is too elusive: in mathematics, one man's month can easily surpass another man's life. When we want to know, how much money we have in our pocket, we all know that it does not suffice just to count the number of coins! The danger is, of course, that for lack of anything more tangible, the "manmonth" —in spite of having been called "mythical"— undeservedly gets the status of a workable unit.

*         *         *

While pondering I came to two terminological conclusions. The one is that my crusade against anthropomorphic terminology in computing science has got a new target: computers don't "decide", for a decision is something for which one can be held responsible. The other piece of misleading terminology identified is the expression: "the design of a programming language"; the expression "the invention of a programming language" seems much more adequate.

*         *         *

I don't know whether it is a cultural gap, a continental gap or a generation gap, but this trip I have faced six times with the same question, and never I could give a sensible answer. The question was "Are you serious?". After the fourth time I tried to explain how this question could be nonsensical by telling a serious joke. In spite of that serious joke, the question was asked another two times!

*         *         *

During the night after my return from California we had 10 cm of snow, and we have had severe frost since then. In the snow our dogs, that used to be regarded as white, seem of a dirty yellow and I walk them in a coat heavier than the one that served me in Detroit. In short: it is winter overhere.

*         *         *

Those who have observed that the leather shoulder strap of my bag needed mending, I can tell that I did so yesterday evening.


1st of February 1976
Plataanstraat 5
NUENEN - 4565
The Netherlands

prof.dr.Edsger W.Dijkstra
Burroughs Research Fellow