When finishing this dissertation I would like to make a short retrospective reflection on my learning experience.

In the book Analects of Confucius, Confucius summed up his life by the following sentence:

    吾十有五而志于学，三十而立，四十而不惑，

五十而知天命，六十耳顺，七十而从心所欲，不逾矩。

Confucius said:"When I was fifteen, I aspired to learn. At thirty, I can be independent. At forty, I am not deluded. At fifty, I knew my destiny. At sixty, I knew truth in all I heard. At seventy, I could follow my heart's desire without overstepping the line."

This reminds me of my own learning experience: when I was a teenager I announced to the world that I wanted to study abroad and obtain a doctoral degree. It was in the early 1980s, when China was sealed off from the world. I was just a little girl who lived in a poor rural region of North China. Born in an illiterate family, I had nothing real at hand besides ambition inspired by a novel, Second hand clasp, which described the life of a Chinese woman who studied abroad and became a famous physical scientist (loosely based on the lives of Wu Jianxiong and Lin Lanying). Actually, I saw no road that could bring my dream to reality.

However I struggled to grasp every chance to learn. Through passing the College Entrance Examination (only 3-5% could pass the examination at that time), I changed my fate. Unfortunately, I majored in library science, which just trains students to follow rules made by human beings. I didn’t like it at all. In the following years, I tried to study journalism by myself and become a journalist. However, I didn’t pass the examination.

After my marriage and giving birth to my son, I began the normal life of a librarian. However, I just sat in the reading room and do nothing. To kill the time, I began to do some mathematical excises and finally I became a master candidate and majored in information science in 2002 in Shanghai, an international city where everything seemed possible. However, as a quite normal student, I could not see an opportunity to study abroad. So I struggled to pass the examination for doctoral candidate.

On April 14 2004, I met Prof. Ronald Rousseau. Knowing I was struggling for the examination for doctoral candidate, he turned to me and said: “Write to me, it is possible for you to be a doctoral student of prof. Jin Bihui and me at the National Library of Sciences CAS (Beijing).”

Possible? Unfortunately I didn’t take part in the examination because I had to take part in another examination on the same day. This possibility then became an impossibility. And though I passed the other examination for doctoral candidate, for some reasons outside myself, I still didn’t get the chance to pursuit my doctoral program.

However, I began to write to Prof. Rousseau regularly. Seeing all failures I experienced in 2005, he still provided me a chance to be a doctoral student of him in 2006 and this at Antwerp University. However, at the time I registered in the Antwerp University, library and information science was in danger to be closed. Moreover, working at Tongji University Library to support my family and, at the same time studying and working on my thesis was not easy. It involved many nightly hours and break-outs of a closed library.

When, in autumn 2006, Professor Rousseau led me to the field of informetrics with the challenge “can you?” I had no concrete research question or objective in mind (although he suggested studying inequality and network measures). Since I like to cope with challenges, I took up the gauntlet. For a long time, I just wandered in the abstract intellectual landscape of informetrics, and met challenges one after another. These propelled me to new challenges and to spaces where I had never been before. As a quite normal librarian, solving these challenges was, initially, quite beyond my capacity. However, with the help of Prof. Rousseau, these challenges motivated and fertilized me. Step by step, I came to the idea to study the evolution of science by the interaction of different ideas as reflected through the citation diffusion process, something no one has ever tried before.

The aim of this dissertation was to root informetrics research into the practice of science, to reveal the regularities hidden in scientific investigations, and to verify if found regularities correspond with observations. I aimed high, the goal set was difficult to attain, but I still think it deserved a try. This is particularly true now that the field of scientometrics is in a crisis: old indicators turn out to be in contradiction with common sense axioms, and new indicators are not accepted yet.

When trying to study the progress of science I found that informetrics, as a discipline, is powerful if it is firmly attached to scientific practice. I admired and still admire such power so I set my destination in informetrics. Writing a doctoral dissertation is just one step in my scientific career. Convincing colleagues of the value of my method and research still seems to be a challenge. Yet, I will continue to cope with all problems and challenges that are coming towards me.

In retrospect it seems magic that my dream of obtaining a doctoral degree abroad is coming true thirty years after I announced it, at a time when it was really an impossibility …… what makes the impossible possible? Time is elapsing when rivers flow to the East……and hope is always hiding in a corner …. And even when one cannot see the corner, don’t be misled by thinking that hope is not there, just work hard and wait ……It is said that all human wisdom can be summed up in the two words “Wait and hope”. Believe that and all dreams will come true one day.…..

I set my heart upon learning when I was a teenager, and in the age of no perplexities, I set my destiny in the field of informetrics. What will I be in my fifties, sixties or seventies?

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