I was born on October 26, 1911 in Kashing, China, a provincial town about one hundred miles south of Shanghai. My father was a lawyer and government official and it was considered certain that I was going to follow in the footsteps. However, in the next 50 years China was destined to undergo momentous changes, with the side result that I was going to immigrate to a new country and eventually to become a member of this great Academy.
In the education of my childhood a main characteristic was the training of mind and outlook of life according to the teachings of Confucius. Much time was spent on Chinese classics, which even now is my hobby. Physical activities were neglected. My inclination toward mathematics was manifest only to the extent that I had no difficulty studying for myself the limited amount of materials on mathematics then available to me.
My family moved to Tientsin in North China and I enrolled in 1926 as a freshman in the College of Science of Nankai University. Lacking experimental skill and interest, mathematics became my only choice of field. The choice was made easy because of the inspiring teaching of my teacher Professor L. F. Chiang. Professor Chiang was the first one in China to start a mathematical library, with subscriptions of current journals. I read with great enthusiasm articles in School Science and Mathematics, Mathematical Gazette, and in particular Hamburger Abhandlungen. The latter contained a series of articles entitled “Topologische Fragen der Differential-geometrie”, some of which are elementary in nature, which opened my eyes.
After my graduation in 1930 from Nankai University, I entered Tsinghua University in Peiping, which was the only university at that time with a graduate program. I was guided to work on projective differential geometry, without realizing that it was a dying subject. The field has many routine problems and it was there that I made my first scientific publication. I should say, however, that one of my papers was better than routine and that it was based on my own idea. In any case it was exciting enough for me to have my paper published in a foreign journal and to be addressed by the Editor as “Doctor”.
It was clear to me that I should study in a western country in order to do serious work. Because of the expenses involved I had to wait for the completion of my graduate studies to be awarded a government fellowship. In 1932visited China end I took notes of his lectures. This, together with my early acquaintance with his work, made it imperative for me to go to Hamburg, when I was awarded in 1934 a government fellowship for studies in a foreign country.
My student years in Hamburg were happy and uneventful. Blaschke gave excellent general advice,gave the most beautiful lectures, and I had many thorough and patient discussions with . The general atmosphere was friendly and informal, in spite of the Nazi activities. I finished my D.Sc. degree in 1936. The thesis was an application of the method of the great French mathematician to problems of the Blaschke school. I was totally impressed by the profundity and importance of Cartan’s works. So when my fellowship was extended another year, I went to Paris. The year 1936–37 which I spent in Paris was decisive on my scientific development. Through personal contact with Cartan, I had a better grasp and perspective of his works, which later played an essential role in a large area of modern mathematics.
I went back to China in the summer of 1937, just at the time when war broke out between China and Japan. In 1937–43 I was a Professor at Tsinghua University and I moved with the University through various parts of free China, following the development of the war. In 1943 I was invited by the Institute for Advanced Study in Princeton to visit the U.S. Although activities in Princeton were restricted on account of the war, the strong tradition in topology allowed me to combine it with my previous training in differential geometry and Lie groups to make some essential progress in global differential geometry. The works done in this period are among the most important that I have done.
After the end of the war I returned to China in 1946. The Chinese government just moved back to Nanking after the conclusion of armistice with Japan. I was asked to organize a newly founded Institute of Mathematics of the Academia Sinica. In the brief period of 1946/48 the Institute played a role in the training of a number of young Chinese topologists and geometers, some of whom are now active in this field. Communist advance toward Nanking and the ultimate collapse of the government made the continuation of my work impossible and I was invited by the Institute for Advanced Study in January of 1949. In the summer of the same year I was appointed a professor of mathematics at the University of Chicago, where I remained till 1960. From 1960 I am a professor of mathematics at the University of California in Berkeley.
I have lectured extensively in universities in America, Europe, and the Orient. I was invited to give addresses in several international conferences, in particular the International Mathematical Congress of 1950 (Cambridge, USA) and of 1958 (Edinburgh, Scotland). In 1960 I was the Colloquium Lecturer of the American Mathematical Society. I have served as Editor of several mathematical journals, including the Proceedings of the AMS and the Transactions of the AMS. I have been an associate editor of many other journals. I am a member of the Academia Sinica (1948) and an honorary member of the Indian Mathematical Society (1950).
I was naturalized a citizen on April 4, 1961. Three weeks later I was elected a member of the Academy. In this regard I am fully conscious of the esteem and appreciation that my adopted country and my colleagues hold for me.