"A. M. Turing Award and my wife are the most wonderful achievements in my life." In 1972, Prof. Yao got his PhD in PhysITCS in Harvard University. He thought he would devote himself to physITCS research. However, he met Frances Foong, who studied mathematITCS and became his wife later. Prof. Yao began to have access to computer science and felt that computer science has more attractions than physITCS. Then he began to study computer science in 1973.
Since he got PhD degree in computer science in Illinois University in 1975, Prof. Yao became a professor and did his research in MIT, Stanford, UC Berkeley and Princeton successively. During these years, with his sharp scientific eyes, Prof. Yao made his great contributions to many pilot fields such as data organization，cryptography, communication complexity and quantum communication and computing. He has received numerous honors and awards, including the George Polya Prize, the Donald E.Knuth Prize and several honorary degrees. He was recipient of the prestigious A.M.Turing Award in the year 2000. Prof. Yao is the first Asian American winner of Turing Award and the only Asian American computer scientist who has received this honor. Turing Award is the most prestigious honor in computer science, and has the same reputation as Nobel Prize in physITCS, chemistry, iatrology and economy.
Prof. Yao in the spot of Tsinghua Forum Shot by Guo Haijun
"Is it possible to have a top university in China in a short period? Is it possible to cultivate a Nobel Prize Winner in China?" From the perspective of computer science, this question could be changed into "Is it possible to have a top discipline of computer science in China? Is it possible to cultivate a Turing Award Winner in China?"
On July 7th, Prof. Yao answered in the 14th Tsinghua Forum: "The answer is affirmative. Tsinghua is doing this!"With his own experience and his practice in Tsinghua University during these past four years, combined with his working experience in American universities, Prof. Yao discussed the hot topic of "top in the world".
Prof. Yao demonstrated that, in China, the discussions on top universities mainly concentrated on culture and system. Therefore, what have been seen are usually negative factors, and the positive ones are often ignored. The importance of top universities is the aggregation of top disciplines, top undergraduate and graduate students and top research results. China has its own advantages in this regard. What we could discuss is that, what advantages China has, how to use the advantages to avoid the arguments of culture and system, pose a specific thinking way and strategy, and construct China's road to Turing Award step by step.
"What I have learnt is fit for a pilot work. If you think I'm persuasive, I'm going to let you know what kind of work and creativity could make you win Turing Award and what kind of work top computer scientists should do."Prof. Yao introduced that theoretical computer science is not a small unit in computer science. At the same time, any top computer science department has a top theoretical computer science team. Theoretical computer science is a decent field and it could supply scientific theoretical basis to computer science. "Computer science has been developing very fast and has new applications during the past 30 years. Every new development needs a mathematical tool to learn the questions and how to solve them. It has demanded to the new mathematical tools, and what theoretical computer scientists do is just this kind of work."
The importance of theoretical computer science
Theoretical computer science not only provides scientific theoretical basis to computer science, but also constructs a new field by mathematical tools and has wide-range commercial applications. Prof. Yao claimed that there are almost 90 professors in computer lab of MIT, and the director of the lab is an Asian American professor. The research of this lab could be divided into 3 fields: artificial intelligence (a generalized category, including robots, graphITCS), system (computer structure, internet, which belongs to traditional computer science), theories (algorithms, information security and so on). More than 20% of professors do theoretical research.
The importance of theoretical computer science could also be seen from the fields of Turing Award Winners. Since 1966, there have been 42 Turing Award Winners, 10 of whom do theoretical computer science research, and the proportion is above 20%.
The core question in theoretical computer science is algorithms. If you have great commercial chance and commercial brain, algorithms could become application right away. Among the colleagues who do theoretical computer science, some brilliant professors became entrepreneurs later. Prof. Yao illustrates that the core technology of Google is algorithms. Thus, theoretical computer science does not mean to do scientific research all one's life. It is possible to become entrepreneurs for some people on the right time and with the right chance.
What kind of creative work could make breakthrough in science? What kind of work could be creative in application? Prof. Yao cites the story from "Tale of Water Margin" to illustrate this question. The heroes in this novel would use some argot when they meet. For example, Priest Hwa Zhishen Lu says "Yu Lin Er Qi" (meet with Chong Lin), and Leopard's Head Chong Lin says "Yu Shan Er Fu" (capture Er Lang Mountain and breach Qing county). Zhishen Lu says "Yu Shui Er Shen" (meet with heroes in Water Margin), and Chong Lin says "Yu Jiang Er Zhi" (meet with Jiang Song and work together). Try to imagine that in modern society, when Zhishen Lu and Chong Lin meet, their aim is not to become the king any more but to become heroes in the modern world by their hard work. They don't know each other at first, and they need a common cipher to have business cooperation. In the Internet Times, they hope to have common understanding in correspondence, forming their own argot. However, we are in the insecure status in communication, and it is possible for other business competitors to know the communication between them. Therefore, it is a very important question regarding how to produce a universal code in public communication. This question was posed in 1976: how to construct a universal code for the two strangers without others knowing it?
For the answer of this question, the first response of most theoretical scientists is: It is impossible with the framework of C.E.Shannon's Information Theory. Any code could be cracked. However, if you are a real enthusiastic and creative person, try to imagine, if we could break the framework, which requires creativity. This is called "thinking outside of the box" in western English. That is to say, people will think within the thinking frame when they meet problems, but you can break the rules, you may think outside of the box.
Let's continue with the example just now. Although most people think it impossible to achieve the goal, we think it might be possible. Both two persons have partial codes, and this is the basis of the possibility. Diffle-hellman, the founder of modern cryptography, claimed that it could be done by code exchange. This is marvelous algorithms. From the example, we could see his creativity. He was thinking outside of the box (C.E.Shannon's information theory). This box trapped people, and if we believe it, we would say it is impossible. However, if you think outside of the box and go into a bigger box, your problem would be solved. This is a very important basic work for cryptography. So far, there have been numerous solutions." says Prof. Yao.
Princeton's Road to Turing Award
Prof. Yao became a professor in Princeton University and came back to China in 2004. He was very familiar with Princeton University. Princeton is one of the Ivy League colleges and they are very prudent. They would not like to make computer science become a department. In 1985, the computer department was founded in Princeton. For one thing, the discipline of computer develops very fast. For another, computer science has developed into a ripe stage. There were 9 professors in computer department, 5 of whom did theoretical computer science research. Prof. Yao and another famous professor Mr. Tarjan were in Stanford at that time, and Princeton enlisted the service of them.
The number of people in computer department in Princeton was small, and half of them did theoretical computer science. Although in some people's eyes, what they did does not belong to mainstream, the practice proved effective. In the second year after Professor Tarjan came to Princeton, he got Turing Award. Prof. Yao got Turing Award in 2000 in Princeton. In 1993, the computer department in Princeton ranked 6th of computer science in NRC ranking. During these several years, the computer department in Princeton became a top one in the world, and this is a marvelous outcome!
Prof. Yao thinks that we could learn from the experience of Princeton. First of all, top discipline could be constructed from advantageous one, and we don't need to be all-round. Secondly, theoretical computer science could become the backbone to enhance the development of computer science in China.
From the larger perspective, it is the same reason to construct a top university. For instance, there are 40 disciplines in the university, and if there are 7-8 top disciplines, it could be called a top university.
Prof. Yao thinks that there are some advantages in China. For instance, we have brilliant students, the economy develops fast and there is a lot of resource to enhance the top universities construction. At the same time, the leaders and teachers know very well about the status quo of universities in China. "It is difficult to find another developing country in the world which has these advantages. We should make use of these advantages to achieve the goal of constructing top universities."
Prof. Yao analyzes that the computer discipline has made great progress compared with that 20 years ago. 20 years ago, people in the field of computer science did not know what researchers were doing in the world and what kind of questions were possible to research. Until now, at least for the computer science discipline, represented by Tsinghua University, we have a common understanding in China and the world, and the results of database, Internet and artificial intelligence are quite good. We have become an influential team in the world, but we still have disparity from the best computer department and lab. "We should have more impacts from the jumping-off point from now. Therefore, we have to think deeply which orientation we are going to head and where we are going to start from, in order to achieve this goal."
Prof. Yao reminds us with the story in "For study----Two monks in Sichuan Province": the most important thing for people is to set a goal in one's life. "I'm still thinking that, in China, we would construct top universities. I hope people could pay more attention to our advantages. We must have this goal to construct top universities and devote to education."
China's Road to Turing Award
How to lead China's road to Turing Award? How to construct a top team and produce the environment to cultivate top teams? Prof. Yao think of two strategies. One is the system reform from top to bottom, and this strategy needs prudence. The other strategy is from bottom to top, which means from top personal research to top team research, to top professional field research and to top computer science development.
"In Tsinghua University, we use both strategies.' He looked back the practice of China's road to the Turing Award that he's been through from 2004.
Prof. Yao thinks that computer department in Tsinghua University has its own advantages. However, theoretical computer science has not fully developed. He claims that this is the best start point, that is to say, to help computer science discipline in China from the perspective of theories. He supposes theoretical computer science has potentiality and could lead a way to computer science in China.
Prof. Yao's idea is very simple. He leads 10 brilliant professors from abroad to form a chair professor team and supervises graduate students. However, he finds out that the new graduate students are very brilliant but lack of basic theoretical conceptions. It takes them at least one year to one year and a half to study theories. With this experience, Prof. Yao produces the thought that elite education should start from undergraduate students. He hopes to set up a special class to cultivate top undergraduate students in computer science.
In 2006, he set up Microsoft Special Pilot CS Class and worked out the program himself, providing a high-level international platform for students: all of the 3rd-year students go to universities in Hong Kong to have academic exchange; send the best students (5-8 students) to prestigious universities in US like Princeton, MIT, Harvard, Stanford and so on to have academic exchange and have short-term classes.
In 2007, Prof. Yao set up the Institute for Theoretical Computer Science (ITCS) and admitted more graduate students. He also set up 2nd chair professor team consisting of 20 professors, 4of whom are members of National Academy of Sciences, 2 of whom are members of National Academy of American Academy of Arts and Sciences, 1 of whom is member of National Academy of Engineering and 2 of whom are winners of Nevanlinna Prize. ITCS sets the goal of becoming the pilot of computer science field in the world and its research results are very attractive. The institute is frequently visited by famous scholars in the world. Stephen Cook, Turing Award Winner in 1982, said in an international conference in 2007:" I thought China is not able to compete with us in the field of theoretical computer science, but now I think we got a competitor, which is the Institute for Theoretical Computer Science in Tsinghua University."
In 2008, Prof. Yao has an intensive idea that he will set up a preresearch class. "We are going to admit some students who will stay in China. We will pick up some potential students from freshmen and sophomores who are very brilliant for teaching them in accordance with their aptitude, in order to have top PhD students in China. We first admitted 8 students from freshmen and 3 sophomores to be in preresearch class."
Why does American education have its own advantage? Prof. Yao analyzes that the reason mainly lies in the famous professors in American universities. These professors could make undergraduate students have scientist's blood and eyes in an early time. "In US, students could succeed only if they are brilliant, diligent and find famous professors as supervisors. However, in China, we need to seek for these students and teach them. What we are going to do is to make students from preresearch class become the best students and top PhD students.
Prof. Yao works out the teaching plan and sets up the program on his own. With his long years' theoretical research and didactical experience from MIT, Stanford and Princeton, he prepares 10 core courses for the class, using advanced method of international computer pedagogy for reference. Furthermore, Professor Yao teaches four courses for this program, introduces to the undergraduate students the series courses of "computer science" and compiles the after-class assignment himself. Every class, he would choose vivid and typical examples to lead the students into ultimate theoretical questions. No textbook could not only have profound ideas of theoretical computer science but vivid explanations as well. Prof. Yao's class does not have invariable teaching plan but full of his research results and experience in the past years, which is the most valuable and precious point. Prof. Yao's class is the most effective and popular class among students.
From fall semester of 2008, Prof. Yao will begin to have classes of advanced theoretical computer science for the 1st-year graduate students. The class is for two terms, and mainly covers complexity, quantum computing, quantum codes and so on, setting up a bridge between study and research for graduate students. It is investigated that although there are theoretical computer science courses in international top universities, the courses only cover the basic concepts of theoretical computer science and separate from research. In China, there's no such kind of course. Prof. Yao designs and teaches the advanced theoretical computer science, combining the theoretical knowledge, in-class discussion and research practice, which show as a bridge between study and research.
To summarize the past four years' work, the chair professors team leading by Prof. Yao has cultivated 8 PhD students, is supervising 20 PhD students and some undergraduate students have graduated. Most work of ITCS is done by students, and their research results are published in top international conferences, highly praised by international scholars. Prof. Yao introduces: "We found an institute to work and have a cultivating line from undergraduate students to graduate students to even PhD students. In these four years, our teaching and research management has been shaped and we have become a famous institute in the world. Our competence has been in the top 10 list in the world."
In these four years, the institute has held many international conferences. Among these conferences, China Theory Week 2007 is pioneering work. We invite the best senior graduate students and exchange academic ideas with graduate students in ITCS. Professor Juris Hartmanis, Turing Award Winner in 1993, said after he attended the China Theory Week 2007 held by ITCS: "This is a very new, creative and important conference. In US, we are not able to do this!" Prof. Yao says: "We have two goals to do this. First of all, after 3-5 years, they are the leading people in this field, and I hope they could interact with our students as early as possible. Secondly, I hope they could do above-PhD research."
"I have one goal for coming back to China. I hope in a short time, in China, I could construct a top research environment at least in my research field." Every word and sentence from Prof. Yao has its strength.
Construct a "highway" in computer field
From Prof. Yao's eyes, Tsinghua's Turing Award Road has covered one third. To summarize his education conception, he says: "we are going to construct a ‘highway' in computer field, letting our students start from undergraduate study till graduate study, professors, and work in the institute, have much better opportunities and feel more glorious than anywhere."
For this reason, Prof. Yao adopts the methodology of "deep cultivation" and "refined cultivation". "Deep cultivation" means to set up an autarkic cultivation system from undergraduate students to researchers; "refined cultivation" means to teach every student in accordance with their aptitude. He thinks only in this way could China cultivate Turing Award Winners.
In the spot of speech, teachers and students from Tsinghua University pay more attention to self-development. A student asks Prof. Yao, Turing plan picks some brilliant students, but what brings for ordinary students in Tsinghua University? Prof. Yao answers: "The answer of this question might wait for several years. Our class is experimental, and not every experiment is by all means good. The result of what we do in Tsinghua University should wait for several years to see." Prof. Yao also mentions that we could cultivate scientists' blood for students. Read more auto-biographies and widen the horizons. The goal of reading is for interest instead of exam.
Someone asks: Should China seek for its own features in theoretical computer science? Prof. Yao says, if we have our own creativities and inventions, these are our features. We don't need to be featured only for features. In scientific work, the whole world is a common group. "Cooperation, exchange and friendly competition, in my opinion, is the best way. History proves that, only in the fully public environment could we have the most rapid development."
When answering the question "as a scholar, which environment is better, home or abroad while doing the research?" Prof. Yao says this answer was affirmative in the past. Even now, in most circumstances, we have better environment abroad. However, what we are doing now is to change the fact. We will have the best environment in China for youngsters to study and develop. He sets the famous The Julliard School as an example: "When this school was founded at the end of 19th century, it formed the idea of constructing top environment in US. In this way, youngsters would have top-ranking education and become brilliant musicians in US instead of studying in Europe. Also, I believe we could set up top computer department and universities in China."