Yibao Xu of Plainsboro, one of the newest members of the West Windsor-Plainsboro Board of Education, had an unusual work experience this summer, contributing to a research project that explored the worlds of archaeology and mathematics. Dr. Xu traveled to Beijing, China, where a unique turn of events ultimately led to this opportunity.
Some years ago robbers in China raided a tomb with treasures of bamboo strips, which were smuggled out to Hong Kong. An antiques dealer there sold the strips to the highest bidder, and the person who bought them was an alumnus of Tsinghua University. In July of 2008, the alumnus donated the bamboo strips — 2,388 strips total — along with some wooden tablets, to the university. Xu says Tsinghua University inherited a major find.
“These bamboo strips are very important. First, their dating has been traced to 2,300 years ago. A substantial part of these bamboo strips is about Chinese classics and history, but a tiny part of this is about mathematics. Twenty-one of the strips put together form a perfect and complete multiplication table,” Xu said.
In 2010 Xu was invited by one of his colleagues to examine the bamboo strips and to collaborate on a research paper titled the “Chinese Multiplication Table.”
Says Xu: “This is an exciting period for doing research on the history of Chinese mathematics. Another set of bamboo strips has been preserved at Yuelu Academy.”
“About 200 bamboo strips dating back to before 186 B.C.E. are on mathematics, and part of which deals with the operation of refractions and multiplication tables. Yet another collection is now at Beijing University, and they also have some counting rods — a tool used to do calculations — and one complete wooden tablet for multiplication tables,” Xu said.
His goal is to incorporate all the historical items, “the newly discovered primary sources,” with transmitted written documents to form a synthetic research paper on Chinese multiplication tables.
Xu is still working with his colleague at Tsinghua University on a final version of the research paper, but the information should be published soon. Xu has traveled to Beijing many times. His first visit to China’s capital city was in 1988 as a graduate student. He went to see the bamboo strips in August of 2010 and was immediately intrigued. But with a college teaching career and his older son Jonathan (a 2011 graduate of High School South) about to enter his senior year of high school, Xu’s interest in taking part in research at Tsinghua was delayed.
Xu teaches college mathematics at the Borough of Manhattan Community College (BMCC) full-time, so he could not find time to go to Beijing for more than a month, let alone the entire semester or school year. Tsinghua University’s Institute for History of Science and Technology & Ancient Texts offered Xu a research fellowship but he could not get release time from BMCC. A long summer break led to this year’s opportunity.
“Our summer ends in May, but at Tsinghua University the summer break starts at the end of June. As soon as my spring courses here ended I flew to Beijing, and as a visiting scholar I was offered six weeks of residency,” Xu explained.
In 2010 Tsinghua was listed as the top college in China for computer science and technology. With his colleagues at the university, Xu says he had discussions about the differences between China’s multiplication tables the mathematical models of other ancient civilizations such as Mesopotamia, the Babylonians and the Egyptians. The professors also spent time comparing various historical multiplication tables.
Xu says the six weeks he spent in China this summer were a marathon. On top of the extensive research, Xu traveled to several Chinese colleges. “I was invited to give talks at Tsinghua University, the University of the Chinese Academy of Sciences, the Institute for the History of Natural Sciences of the Chinese Academy of Sciences, and Shanghai Jiao Tong University,” he said.
At each of the four institutions Xu lectured on “George Sarton and Chinese Science or Chinese Mathematics.” Sarton (1884-1956) was the Belgian chemist and historian known as “founding father of the history of science in the United States,” Xu said. At each university he tailored the lecture to either be more history-of-science-based or history-of-mathematics-based depending on the audiences, which varied from graduate students to professionals or postdoctoral research fellows.
“I went through his archive at the Houghton Library of Harvard University and dug out some correspondence between him and Chinese scholars in his time as part of my research project on Western historiography of traditional Chinese mathematics. Basically I talked about George Sarton and Chinese mathematics. When he wrote his monumental work ‘Introduction to the History of Science’ part of the book dealt with Chinese science. I focused on how he wrote accounts of Chinese science and mathematics,”
He says Tsinghua University intends to send a research paper about the collection of bamboo strips and wooden tablets to well-known international journals for science and nature. “As soon as that general paper is published, I am ready to send out my paper to top journals such as Historia Mathematica or Archive for History of Exact Sciences,” he said
Towards the end of his stay in China, Xu visited Hohhot, the capital of Inner Mongolia Autonomous region, to lecture at Inner Mongolia Normal University. He spoke about Chinese Euclid’s Elements, first published in 1607, and their English sources; the basis of research work Xu did over 10 years ago.
“They are still interested in that subject,” Xu says.
It appears that his latest research will also capture people’s attention over a long time, on both sides of the globe.
