Yang Weidong, 44, a Beijing-born interior designer and independent documentary producer, has been working for two years on a documentary titled Signal, aimed at interviewing 500 scholars about the state of academia on the mainland. He is determined to carry on despite pressure from the authorities to stop. How did you get started on this documentary? In 2007, I began a documentary featuring interviews with people in sports circles who might know something about mainland athletes taking stimulants in the late 1970s and early 80s. The authorities stopped my work in December 2008 because it was very sensitive. So I began thinking about doing another project, giving liberal scholars a chance to express their opinions freely as a way to protest. I have interviewed more than 200 scholars. How do you choose your interviewees and select questions? They are scientists, artists, writers, philosophers, economists and historians, all above 35 years old. They must have gone through some frustrations in life that they could reflect upon. The questions are on humanity issues that are distorted in this society. I ask them to redefine things that we don't normally think about. In the interview request, I list only 13 general questions, including what order is, what a belief is, what the meaning of life is and what kindness is. But I usually ask a lot more. The sessions have lasted between one and four hours. What challenges do you face? At the start, it was sometimes hard to secure an interview. Many were a bit suspicious about my purpose. Some thought I was a speculator. Now that I have interviewed quite a few, it's getting easier. Even so, many still say no. Another challenge is funding. I have a team of about 10 full-timers and part-timers, and have invested a few million yuan, which I got by selling my paintings and two flats. Sure I would like to get returns for my input. My wife is concerned because I haven't made any income for two years. But she is very supportive. What problems have officials posed? They invited me for a cup of tea [a euphemism for an interrogation] as they probably feared the uncertainty of what I would do with those liberal voices and that if I sold my film, their views would be known to the public. They said 47 of my interviewees were 'sensitive' people. I told them I was doing this only for money. I had to halt my work during the sensitive time last month [December 12 was the day of the Nobel award ceremony for Liu Xiaobo ]. It's now a big victory each time I complete an interview. What is the significance of the work? Recording the text alone is not enough to communicate with your audience. I would like to record the history and what the social elite think. It's quite meaningful to compare different reactions to the same questions. Scholars can be arrogant. When their opinions are controversial, they are valuable. Who impressed you the most? Professor Cai Dingjian [director of the Institute for Study on Constitutionalism at the China University of Political Science and Law, who died on November 22]. When I requested an interview in April, he said he would do it in three months. I didn't know he had just been diagnosed with cancer. We spoke for two hours, during which he took medicine. He seemed to be in pain but was trying to endure it with his willpower.