My teachers at PLU. . .

Learning for life in and outside the classroom

Chang-li Yiu

Professor Emeritus, Mathematics and Physics

Born in mainland China, Yiu received degrees in Taiwan and at Columbia before coming to PLU in 1973. He served at different times as professor, dean and chair in the Mathematics and Physics Departments at PLU until his retirement in 2005.

I retired from PLU in 2005, after about 30 years of teaching in both the Mathematics Department and the Physics Department. In a sense the year I retired was also the year I graduated from PLU. I would like to tell you about some of my teachers.

I came to PLU in 1973 for a temporary teaching position in the Physics Department. The appointment ended in the summer of 1975. Before I left, the Mathematics Department offered me an appointment.

This offer came unexpectedly, partly because the chair of Mathematics, Prof. Ken Batker, came to know me only after I fired off a harsh memo to the Mathematics Department, questioning its effectiveness in teaching calculus—a student in my physics class, who had passed calculus, could not do a very basic mathematical operation. Ken came to me immediately with the textbook and sample tests. With no sign of anger, he explained what his department did in calculus. I saw nothing wrong. Only years later did I realize that some of my own students could have forgotten what I taught them sooner than I thought.

I learned from Ken how to be a person with a big heart, and later on, to be an administrator who avoids behaving self-importantly. Ken was my first teacher at PLU.

Without knowing it at the time, I had a lot of nerve when I accepted the offer to teach in Mathematics. My graduate work was in physics, not mathematics. But like most physicists, I believed that I could do anything. Didn’t I use all kinds of fancy mathematics in physics? At the college level of mathematics instruction, what difference is there between bona fide mathematicians and me?

True, most students probably could not tell the difference. But soon I realized that there was one: Physicists looked at mathematics as a tool, whereas mathematicians viewed it as a system of thoughts. If I wanted to teach real mathematics, not just applied mathematics, I had better learn the mathematicians’ way. And I found a ready teacher, my colleague Prof. Chris Meyer. He opened my eyes to subtleties of the mathematical language. Moreover, I tended to be a careless thinker. When solving problems, I often unknowingly skipped steps. I always enjoyed Chris as my critic and marveled at his ability to pick up on my oversights.

My other teacher of mathematics, Prof. Mike Dollinger, joined the Mathematics Department not long after I did. Mike was not only a fine mathematician, but also one of the best lecturers I’ve ever known. He was a stickler on precise wording. His lectures were always exceptionally clear. I often asked him to explain mathematics to me. If it was sunny, we would take a walk and he would give me a beautiful lecture without notes or preparation.

I started to do research on atomic physics with Prof. K. T. Tang in 1989. K. T. was an acknowledged specialist in atomic physics, whereas I hardly knew anything significant about the subject. Obviously he had to bring me up to date. But more than that, he was my critic in physics just like Chris was in mathematics. When I heard him say, “Chang-li, I know you are smarter than I. But….” I would burst into laughter. I knew he was applying the cream before shaving me.

Once, after we published some papers on the “exchange energy” between two hydrogen atoms, we decided to tackle exchange energy among three hydrogen atoms. The problem was that we did not know what “exchange energy” meant when it came to three atoms. I tried to come up with a definition. But over and over again K. T. demolished my attempts. In desperation I wished that he would just give up and accept my solution. But I also knew that he was right. Finally one day I was lying on my bed in exhaustion, thinking that I would never find the answer. Suddenly the answer came to me. K. T. accepted it right away. He taught me to be persistent and never to accept half-baked ideas.

Our collaboration came to an end when I became dean of the sciences division in 1998. By then I needed a new teacher. Written by a non-native English speaker, my official communication required substantial polishing before it could see the daylight. Luckily my colleague Ms. Anita Wahler, who held an administrative job to help the dean, was not only a good writer, but also an excellent editor. She became my English teacher. Although she is no longer at PLU, she remains my teacher. If my column here is free of too many mistakes, it is because of her editorial help. I am also learning from her to ruthlessly prune redundancies and secondary ideas from my writings.

I also audited courses formally. I was in Prof. Dennis Cox’s printmaking class and Prof. Walter Tomsic’s painting class. Both were excellent craftsmen. Walter was a severe but insightful critic. I also enjoyed sitting in the German class of Prof. Webster and the French class of the late Prof. Spangler.

And there were teachers who helped me with immediate problems as well, too many to mention them all. I often ran to Prof. Bryon Dorner with a mathematical passage and was amazed by his instant grasp of its meaning, which had eluded me. I listened to a beautiful tune in a Paris café and was unable to find someone to name the tune, until Prof. Giddings of Chemistry said that it was Bach’s double violin concerto. Gail Walker, who was a student, introduced me to the writings of Lewis Thomas, one of my favorite essayists.

All people I mention above are either retiring or have left PLU. Consequently, this letter is not a commercial. But don’t despair. If you have the will to learn, you’ll find teachers everywhere. The Chinese have a wonderful term, “one-word teacher,” which means it doesn’t take a great scholar to be your teacher. Confucius said, “Among a party of three, there is certainly one who could be my teacher,” and added, “Choose good qualities to imitate and bad ones to correct myself.” This means that you can truly learn from anyone, anywhere.