For most of his public life, 51-year-old Ai Weiwei has been associated with the leading edge of art and design. Ai's credits extend from being a co-designer of Beijing's 'Bird's Nest' National Stadium to being a standard-bearer for mainland contemporary art, and one of the most saleable Chinese artists. But, in the past few years, Ai has changed tack. He still breaks rules, but these days the burly, bearded Beijinger is taking on public issues through his outspoken social commentary. His pungently worded weblog is one of the most read on the mainland, attracting an audience keen to read his comments on social events and the curses he heaps on authorities over cultural defects, social unfairness and political problems. If the blog were a picture, it would be one of his Study of Perspective photographs, which show Ai making an obscene gesture at various sites such as Tiananmen Square and the White House. He repeatedly stresses that he points the finger at the things he regards as unfair or against the fundamental values of justice, transparency, fairness and freedom of expression, which he seeks to uphold by writing blog articles and talking to the media. Sitting in his sunny, spacious home in a suburban Beijing 'artists' village', Ai said he had never regarded himself as an artist, even though every work he completed was 'purchased immediately'. 'My close friends know that 17 hours of my day are spent on the internet, talking to the media on public issues or sitting down here alone because I love being isolated,' he said, insisting that his biggest concern was to express his understanding of the world unfettered. 'As a so-called artist, my biggest desire is not to hang pictures on a gallery wall or exhibit my works in a special place. It's important for me to effectively participate in a change of ideology, of the basic values of most people, and to embody this action in some way. This is what I see as art.' That action has already taken a number of controversial but creative forms. Last month, he launched a campaign with friends and volunteers to 'harass' Sichuan officials with phone calls about schools that collapsed in the May 12 earthquake to determine how many students had died. 'If the government couldn't disclose the facts, we will do it as volunteers to embarrass them,' Ai said. He also put his name to the highly sensitive Charter 08 document. Dissident Liu Xiaobo was arrested in December for allegedly drafting and collecting signatures for the document, which advocates political reform, democracy and human rights. He remains in custody with no formal charges filed. 'I signed the charter in the third batch of signatories after hearing that my friend Liu Xiaobo was arrested,' Ai said. 'What's wrong with issuing an open letter? I hate to see [someone arrested for that]. That's the only reason I signed. I read the charter and was not impressed with the lengthy expression of unexciting values.' Ai said he had been addicted to loneliness from childhood, and still enjoyed 'being isolated and being different'. His father was Ai Qing, a famous, unrepentant, free-thinking modern poet who was targeted in the anti-rightist campaign of the 1950s and sent to a labour camp. At just one year of age, Ai Weiwei went along. 'I scrubbed toilets with my father from a very young age, so I am subconsciously used to unfairness.' Ai eventually returned to Beijing and enrolled at the Beijing Film Academy in 1978 to study design. Like famed filmmakers Zhang Yimou and Chen Kaige, he was among the first generation of students after the national college entrance exams resumed. In his spare time, he was a member of the first group of avant-garde Chinese artists called The Stars, and spent a lot of time with poets such as Bei Dao and A Cheng, who helped shape his liberal values. Ai said he became increasingly aware of unfairness in the system in 1979 with the arrest of dissident Wei Jingsheng and the suppression of Beijing's Democracy Wall, a notice board for dissent and criticism, usually in the shape of big-character posters. 'I suddenly realised this nation and its government were wrong.' He quit the school in 1981 and headed to the prestigious Parsons School of Design in New York for another decade of 'self-exile' in the US - a nation he describes as 'paradise for a wild person'. Without a degree or US passport, he returned to China in 1993 after trying 'all the jobs an illegal immigrant could do'. He spent years publishing underground art magazines but deliberately kept his distance from the local artistic and intellectual communities because they were 'people I disdained for their insincerity in contributing their knowledge and art to tell the truth to change this society in a positive way'. 'Art is indispensable to people's consciousness, perception, self-identity and core values. Artists possess certain privileges and power, but if your profession is to express your ideas and you don't serve the public, what's the meaning of it?' Ai said. Ai said he enjoyed talking to the media, especially to the mainland media, even though he knew that his political remarks would be 'censored or self-censored by reporters and editors'. 'I often need to explain [to the reporter] about fundamental values - what equality and fairness are, how to make them a reality, why press freedom is important in this country [when] people's awareness is just above the beginning level,' he said. 'But it's a great chance for me to talk. Democracy and equality, which I treasure, have to be realised on this piece of land, in China, eventually.' So why does he think he has survived in the public sphere despite his caustic remarks? Ai said there were risks but times had changed. 'I am a Chinese citizen holding a Chinese passport, and so I have to accept the legal and political risks of my remarks, if there are any,' he said. 'But I don't think that the risks in this era are as terrifying as they were decades ago in my father's time. 'Life is just like sailing: you never know when you will hit a reef, but it's useless to guess when it will happen.'