Armstrong: Yes. And then you’d put it all together. I don’t know if that counts as learning programming. When I went to university I was in the physics department at University College of London. I think we probably had programming from the first year. Then you had this turnaround of three hours or something. But again it was best to run about four or five programs at the same time so you got them back fairly quickly.

Seibel: In high school, was it an actual school course?

Armstrong: It was an after-hours course—computer club or something. We went to see the computer, I remember. Lots of serious-looking older men wearing white coats with pens stuck in their pockets wandering around, like, a church. It was a very expensive computer.

Seibel: You were studying physics; when did you shift to programming?

Armstrong: Well, as an undergraduate some of the courses involved writing programs and I really enjoyed that. And I got to be very good at debugging. If all else failed, I would debug people’s programs. The standard debugging was one beer. Then it would go up—a two-beer problem or a three-beer problem or something like that.

Seibel: That was in terms of how many beers they had to buy you when you debugged their program?

Armstrong: Yeah, when I fixed their program. I used to read programs and think, “Why are they writing it this way; this is very complicated,” and I’d just rewrite them to simplify them. It used to strike me as strange that people wrote complicated programs. I could see how to do things in a few lines and they’d written tens of lines and I’d sort of wonder why they didn’t see the simple way. I got quite good at that.

When I really got to programming was after I finished my first degree and I decided I wanted to do a PhD. So I started to do a PhD in high-energy physics and joined the bubble chamber group there and they had a computer. A DDP-516, a Honeywell DDP-516. And I could use it all by myself. It was punched cards, but I could run the programs there—I could put them into the thing and press a button and whoomp, out came the answer immediately. I had great fun with that. I wrote a little chess program for it.

This was when real core memory was knitted by little old ladies and you could see the cores—you could see these little magnets and the wires went in and out. Frightfully expensive—it had something like a 10MB disk drive that had 20 platters and weighed 15 kilos or something. It had a teletext interface—you could type your programs in on that.

And then came this “glass TTY” which was one of the first visual display units and you could type your programs in and edit them. I thought this was fantastic. No more punched cards. I remember talking to the computer manager and saying, “You know, one day everybody will have these.” And he said, “You’re mad, Joe. Completely mad!” “Why not?” “Well, they’re far too expensive.”

That was really when I learned to program. And my supervisor at the time, he said, “You shouldn’t be doing a PhD in physics. You should stop and do computers because you love computers.” And I said, “No, no, no. I’ve to finish this stuff that I was doing.” But he was right, actually.

Seibel: Did you finish your PhD?

Armstrong: No, I didn’t because I ran out of money. Then I went to Edinburgh. When I was reading physics we used to go and study in the physics library. And in the corner of the physics library there was this section of computer science books. And there were these brown-backed volumes called Machine Intelligence, Volumes 1, 2, 3, and 4, which came from Edinburgh, from the Department of Machine Intelligence there. I was supposed to be studying physics but I was eagerly reading these things and thought, “Oh, that’s jolly good fun.” So I wrote to Donald Michie, who was the director of the Department of Machine Intelligence at Edinburgh, and said I was very interested in this kind of stuff and did he have any jobs. And I got back a letter that said, well, they didn’t at the moment but he would like to meet me anyway, see what sort of person I was.

Months later I got a phone call, or letter, from Michie, saying, “I’ll be in London next Tuesday; can we meet? I’m getting the train to Edinburgh; can you come to the station?” I went to the station, met Michie, and he said, “Hmmm! Well, we can’t have an interview here—well, we’ll find a pub.” So we went to a pub and I chatted to Michie and then a bit later I got another letter from him, he says, “There’s a research job at Edinburgh, why don’t you apply for it.” So I became Donald Michie’s research assistant and went to Edinburgh. That was my transition between physics and computer science.

Michie had worked with Turing at Bletchley Park during the second World War and got all of Turing’s papers. I had a desk in Turing’s library, so all around me were Turing’s papers. So I was a year at Edinburgh. After that Edinburgh kind of collapsed because James Lighthill, a mathematician, was hired by the government to go and investigate artificial intelligence at Edinburgh. And he came back and said, “Nothing of commercial value will ever come out of this place.”

It was like one gigantic playpen kind of place. I was a founding member of the British Robotics Association and we all thought this was really going to have enormous relevance. But the funding agencies—Robotics! What’s this stuff? We’re not going to fund this! And so there was a period around ’72, I guess, when all the funding dried up and everybody said, “Well, we had fun while we were here; better go and do something else.”

Then it’s back to being a physicist. I came to Sweden and I got a job as a physicist programmer for the EISCAT scientific association. My boss had come from IBM and he was older than me and he wanted a specification and he would go and implement it. We used to argue over this. He said, “What’s bad about the job is we don’t have a job description and we don’t have a detailed specification.” And I said, “Well, a job with no job description is a really good job. Because then you can form it how you like.” Anyway, he left after about a year and I got the boss’s job, the chief designer.

I designed a system for them and that was what I suppose you’d call an application operating system—it’s something that runs on top of the regular operating system. By now computers were becoming quite reasonable. We had NORD-10 computers which were Norwegian—I think they were an attempt to get into the PDP-11 market.

I worked there for almost four years. Then I got a job for the Swedish Space Corporation and built yet another application operating system to control Sweden’s first satellite, which was called Viking. That was a fun project—I’ve forgotten the name of the computer but it was a clone of the Amdahl computer. It still only had line editors. It didn’t have full-screen editors. And all your programs had to be in one directory. Ten letters for the file name and three letters for the extension. And a Fortran compiler or assembler and that’s it.

The funny thing is, thinking back, I don’t think all these modern gizmos actually make you any more productive. Hierarchical file systems—how do they make you more productive? Most of software development goes on in your head anyway. I think having worked with that simpler system imposes a kind of disciplined way of thinking. If you haven’t got a directory system and you have to put all the files in one directory, you have to be fairly disciplined. If you haven’t got a revision control system, you have to be fairly disciplined. Given that you apply that discipline to what you’re doing it doesn’t seem to me to be any better to have hierarchical file systems and revision control. They don’t solve the fundamental problem of solving your problem. They probably make it easier for groups of people to work together. For individuals I don’t see any difference.