Peter Rosenthal
Queens College of City University of NY
B.S. Mathematics, 1962
University of Michigan
MA Mathematics, 1963
University of Michigan
Ph.D. Mathematics, 1967
Professor of Mathematics
University of Toronto

From childhood to the present, I have always found mathematics to be the most beautiful of subjects: the elegance of the nicest proofs (such as that of the infinitude of the primes) impresses me more than any other art. This is the reason I studied and continue to study mathematics, although I now also have a second career.
In 1969 I was a young Assistant Professor of Mathematics at the University of Toronto. The war in Vietnam was raging, and there were frequent protest demonstrations in front of the U.S. Consulate. I was giving a speech at one such when the police told me to stop. I kept speaking. The head of the riot squad told me he would arrest me if I continued. I did, and he did. I was charged with two minor but criminal offences, as were the several people who valiently picked up the bullhorn and tried to continue the rally after I was arrested.
Upon reflection I realized that it would be a drag to have a criminal record, so I worked hard preparing my trial with a lawyer. When my lawyer and I disagreed about trial tactics, I fired him and represented myself (with the judge emphasizing that I had a fool for a client). I was acquitted of one charge and convicted of the other at trial; on appeal I was acquitted of the second charge as well.
In the course of representing myself I learned a bit about criminal law and procedure. Over the next twenty years I represented many demonstrators for various good (in my definition that means "leftist") causes. I was a paralegal, with no training but lots of enthusiasm. On several occasions I was frustrated by my lack of a degree in law. For example, as a nonlawyer I couldn't appear in appellate courts (representing anyone other than myself), and I also couldn't represent people charged with more serious offences.
Therefore in middle age I decided to go to law school. After torturous negotiations, the University administration agreed that I could do so while remaining a math professor if I taught the normal teaching load (but was allowed to have my classes in summers and evenings) and maintained my research and supervision of graduate students. However, I would get sabbatical (82%) pay rather than full pay. (Some people think I got a good deal, some think the administration got the better of me; maybe it was actually quite reasonable.)
It was interesting becoming a student again. After I had taken my final oral examination on my Ph.D. thesis I had vowed I'd never take any other test. This vow was quickly forgotten in law school. I have since advocated forcing professors to, say once every five years, take a course outside their area of expertise and get graded on it  this might produce a little more sympathy for students.
Anyway, I got through law school(and even enjoyed it a bit) while continuing mathematical teaching and research, and was called to the bar of Ontario in 1992. Now there are no formal restrictions on my legal practice and I take more cases than I really want. Most of the cases are still representing protestors of one kind or another, and most of the cases cost rather than earn money. But I get a lot of satisfaction from contributing in that way to causes I believe in.
I still do research (in the theory of operators on Hilbert space) and teach mathematics. My legal and mathematical lives are generally as distinct as Dr. Jeykel's and Mr. Hyde's.
When I was in law school, the dean introduced me to a visiting professor by saying to him "You might like to meet Peter Rosenthal, he's a professor of mathematics as well as a student in the Faculty of Law."
"That's very interesting," the visiting professor said, "what do you think about the relationship between mathematics and law?" "I don't see much relation," I replied. "Well," he said,"Kant wrote that the only two true sciences are mathematics and law." "He was right about mathematics," I answered.
And I still think that that is so. Law sometimes makes a pretense of being logical, but it is only a pretense.
There have been a few times when being a mathematician helped me with law. One such time was reported by Ed Barbeau in his "Fallacies, Flaws, and Flimflam" column in the College Mathematics Journal volume 28, in November 1997 on page 377. On another occasion, my being a mathematician gave me the courage to really probe an "expert" witness who claimed that the "flexion" of a graph proved my client was guilty. Although the expert first claimed that the definition of "flexion" was too complicated for the court to understand, crossexamination revealed that the "expert" had no real definition in mind. We won the case. Such instances are rare, however. Generally, mathematics and law are very separate (sometimes competing) parts of my life. They each provide great satisfaction, and some tension and unpleasantness. I'm glad I make a living as a math professor: I would not enjoy having to take legal cases I didn't believe in just because I needed the money. Fermat, on the other hand, made a living as a lawyer and did mathematics as an amateur. I know that his mathematics was much better than mine; I wonder if I'm as good a lawyer as he was?
