JOHN BACKUS: a restless inventor

We didn't know what we wanted and how to do it. It just sort of grew. The first struggle was over what the language would look like. Then how to parse expressions --- it was a big problem and what we did looks astonishingly clumsy now.... John Backus on the invention of FORTRAN

Necessity, says the adage, is the mother of invention. Yet some inventors are motivated less by necessity than by sheer irritation at the messiness or inefficiency of the way things are. John Backus is such an inventor. He played an inspirational role in three great creations: FORTRAN, the first high level programming language; Backus-Naur Form, which provides a way to describe grammatical rules for high level languages; and lastly a functional programming language called FP, which advocates a mathematical approach to programming. Today, each of his inventions drives research and commercial agendas throughout the planet. Yet Backus's own life is one of restless energy --- from his youth through his retirement.

A distaste for inefficiency seems to run in the family. Before World War I, Backus's father had risen from a modest background to the post of chief chemist for the Atlas Powder Company, a manufacturer of nitroglycerine to be used in explosives. His promotion came for good reason.

Their plants kept blowing up or having very poor yields and they couldn't figure out why. The yield was very temperature sensitive. My father discovered that the very expensive German thermometers they had were incorrect. So, he went to Germany and studied thermometer making and got some good thermometers and their plants stopped blowing up so much.

During World War I, Backus senior served as a munitions officer. A promised postwar job at Dupont never materialized, so he became a stockbroker instead. By the time John Backus was born in Philadelphia in 1924, his father had grown rich in the postwar boom. Backus spent his early years in Wilmington, Delaware and attended the prestigious Hill School in Pottstown, Pennsylvania.

I flunked out every year. I never studied. I hated studying. I was just goofing around. It had the delightful consequence that every year I went to summer school in New Hampshire where I spent the summer sailing and having a nice time.

After a delayed graduation from the Hill School in 1942, Backus attended the University of Virginia, where his father wanted him to major in chemistry. Backus liked the theory, but hated the labs. He spent most of his time at parties, waiting to be drafted.

By the end of his second semester, Backus attended only one class a week --- an untaxing music appreciation class. Finally, the school authorities caught up with him and his career at the University of Virginia ended. He joined the Army in 1943.

Backus became a corporal in charge of an antiaircraft crew at Fort Stewart, Georgia, but his performance on an aptitude test convinced the Army to send him to a pre-engineering program at the University of Pittsburgh. A later medical aptitude test may have saved his life.

My friends were shipped off to the Battle of the Bulge and I went to Haverford College to study pre-med.

As part of the pre-med program, Backus worked at an Atlantic City hospital in a neurosurgery ward that treated head wounds. Through a bizarre coincidence, Backus was diagnosed with a bone tumor and a plate was installed in his head. Soon after, he attended medical school at Flower and Fifth Avenue Hospital (now New York Medical College), but that lasted only nine months.

I hated it. They don't like thinking in medical school. They memorize --- that's all they want you to do. You must not think.

Backus also found out that the metal plate in his head did not fit properly. A nearby Staten Island hospital specialized in plates. Backus went there to have a replacement made. Not satisfied with the proposed design, he got to know the technicians and designed his own. After that, Backus quit the medical field. He took a small apartment in New York City for 18 dollars a month.

I really didn't know what the hell I wanted to do with my life. I decided that what I wanted was a good hi fi set because I liked music. In those days, they didn't really exist so I went to a radio technicians' school. I had a very nice teacher --- the first good teacher I ever had --- and he asked me to cooperate with him and compute the characteristics of some circuits for a magazine.

I remember doing relatively simple calculations to get a few points on a curve for an amplifier. It was laborious and tedious and horrible, but it got me interested in math. The fact that it had an application --- that interested me.

Backus enrolled at Columbia University's School of General Studies to take some math courses. He disliked calculus but enjoyed algebra. By the spring of 1949, the 25 year-old Backus was a few months from graduating with a B.S. in mathematics, still without any idea what to do with his life.

One day that spring, Backus visited the IBM Computer Center on Madison Avenue. He was taken on a tour of the Selective Sequence Electronic Calculator (SSEC), one of IBM's early electronic (vacuum tube) machines.

The SSEC occupied a large room, and the huge machine bulged with tubes and wires. While on the tour, Backus mentioned to the guide that he was looking for a job. She told Backus to talk to the director.

I said no, I couldn't. I looked sloppy and disheveled. But she insisted and so I did. I took a test and did ok.