Kristen Nygaard (1926-2002)

Three weeks short of his 76th birthday, Kristen Nygaard left us.

Kristen's numerous accomplishments during a vibrant fifty-four-year career can be seen at Some of them can be inferred from his obituary of Dahl. I will mention just a few highlights, and add some personal notes.

During the 1960's, Kristen and Ole-Johan designed the first object-oriented language, Simula. Its second incarnation, Simula 67, inspired both Smalltalk and C++.

In the 1970's, Kristen was an early advocate of user participation in industrial systems design. His social research into the impacts of new technology on workers influenced landmark union-management agreements and legislation, in Norway and other countries.

In the 1980's, Kristen and colleagues completed the design and implementation of Beta, an object-oriented language with ambitious goals. Beta unified procedure parameter lists and objects into a single abstraction called a "pattern".

In the early 1990's, Kristen led a political organization that persuaded the Norwegian electorate to reject membership in the European Union. After the victorious vote, he retreated from public view to resume research and teaching.

In June 2002, he secured research funding for COOL, a project aimed at improving the teaching of object-oriented design.

During his career, Kristen won numerous prestigious awards. In 1990, CPSR awarded him the Norbert Weiner Prize. This year, he and Ole-Johan shared the ACM Turing Award and the IEEE von Neumann Medal.

I first met Kristen at the January 1978 ACM SIGPLAN Conference on the History of Programming Languages. The following year, during my first trip to Europe, he and I began what turned out to be a lifelong exchange of visits.

In both the lecture hall and the living room, Kristen was a raconteur. His delightful stories and boisterous jokes were especially unrestrained when fueled by adequate quantities of aquavit.

One sabbatical year, Kristen and his indomitable wife, Johanna, lived in a house of mine in Palo Alto. That experience gave the activist duo an unforeseen modicum of appreciation for the positive attributes of American society.

I once encountered Kristen unexpectedly at a hotel near Heathrow Airport. He had come to London to attend a dinner with the Queen of England. He was about to take an afternoon nap in preparation. Inexplicably, the hotel did not place the 5:00 p.m. wake-up call that he requested. He slept too late to attend.

He must have been disappointed, for the trip from Oslo was essentially wasted. But at breakfast the next day, he simply laughed it off, explaining that the hotel had also made a second mistake. They had placed a wake-up call that morning that Kristen had not requested. That call came at precisely 5:00 a.m.

In January, Kristen frankly discussed his mortality with my wife and me. He presciently told Colleen that he did not expect to see her again. Still, his sudden heart attack last Friday night came as a shock to everyone. Many of his friends were looking forward to seeing him in November at OOPSLA, where he was to deliver the Turing lecture.

I will miss Kristen's periodic phone calls, in which he would identify himself by saying the single word, "Ja", before launching directly into a travel itinerary, a status report, or a Macintosh question. I will miss his wisdom, humor, compassion, affection, and joie de vivre. He was a dear friend to many, and to me.

- Larry Tesler, Aug. 13, 2002