Another profile on the list for possible inclusion in the anthology *Profilia*, which is coming latter this summer, is one of my last pieces for *Johns Hopkins Magazine*, about film editor, sound designer, and polymath Walter Murch. Here's a bit that begins with the journalist Lawrence Weschler:

Weschler sometimes talks about how Murch used to carry around a cloth sack filled with slips of paper. He would extend the pouch and urge you to take out one of the slips. Each one carried a snippet of text, something Murch thought you might find interesting or provocative: “Translate the invisible wind by the water it sculpts in passing—Robert Bresson.” “If at first the idea is not absurd, then there is no hope for it—Albert Einstein.” Receive email from Murch and you will discover that to each note, Murch appends not an email signature but an image or curious fact. In my correspondence with him, he has sent a photo of a 4,650-year-old pyramid at Meidum, Egypt; a portrait of Vasili Arkhipov with the story of how, as a Soviet submarine officer in 1962, Arkhipov vetoed the impending launch of a nuclear torpedo at a U.S. aircraft carrier during the Cuban missile crisis; a diagram he devised to show the atomic particles of the standard model of physics; and a microphotograph identified only as “cross-section of Gustav Klimt’s neurons.” All byproducts of time spent in various rabbit holes.

“Right now, I’m obsessed with the object called Plimpton 322, which is a piece of clay with cuneiform mathematics on it that seems to indicate that 3,200 years ago, the Babylonian Sumerians knew about the Pythagorean theorem and had a kind of trigonometry,” he says. (Pythagoras, again. With Murch, things have a way of coming back around for new convergences, as you will see.) “I’ve been riding that particular hobby horse for the last couple of months. I wrote a paper on the Pythagorean theorem for a course in high school and probably ran across Plimpton 322 then. It was in the news again two or three months ago for some research that some mathematicians have done in Australia. There’s a real tug-of-war between people who believe that it is a trigonometric table and people who think that it isn’t. So, I was trying to determine for myself what it was.” He has been using mathematics software to work out what might have been the Sumerian math. “It’s written in sexagesimal mathematics, which is how the Sumerians worked, base 60 rather than base 10, so you have to convert the numbers. Once I did that, it all seemed pretty clear to me. I finally came down on the side of yes, it is definitely a trigonometric table. It has what we’d call tangents and secants and that kind of stuff.”

The tablet, he says, looks to be an exercise book that would be given to a student. It has four columns and 15 rows. One column is the number of each row, one the length of the hypotenuse of the triangle, one the length of the “short” leg of the triangle. “And the last column is the square of the tangent of the angle shared by the hypotenuse and the short leg, and this would permit a smart student to derive the length of the missing long leg of the triangle,” Murch says. “It’s just a remarkable thing to think that 3,200 years ago, people were dealing with pretty sophisticated mathematics. Then it all seemed to disappear. There was something called the Bronze Age collapse around 1200 B.C. that decimated the civilizations of the Near East, and a lot of that information was lost and had to be recovered later. It was kind of like our Dark Ages in Europe.”

He is patient while he waits to see whether anyone in astrophysics takes up his ideas about Titius-Bode. “These things take time,” he says. “I’m perfectly happy in my rabbit hole. I have a day job making movies. I don’t watch television, so I have to do something in the evening. My wife knits, and I sit here doing pyramid stuff or Plimpton 322 stuff. She shows me her knitting and I show her my diagrams and we each say, ‘That’s nice, dear.’”