Chen Guangcheng spent the most part of 10 years behind walls - in jail or at home under strict house arrest in the eastern province of Shandong.

The blind dissident who exposed forced abortions and campaigned for land rights was charged with "damaging property and organizing a mob to disturb traffic."

He then scaled the wall around his home, injuring himself in the process, and took a getaway car to the US embassy where he requested asylum. He now lives in New York.

Visibly moved by the past

On a four-day visit to Berlin, the 42-year-old was visibly moved at Brandenburg Gate. Out of respect for the victims of the former East German dictatorship, he crossed the line where the wall used to be several times. "No wall that is built against the will of the people can stand for a long time," he said. "No dictatorship can suppress people's longing for freedom forever."

Chen said it was important not to forget the past and the victims of the GDR even though the Berlin Wall now belongs to history.

"There are many visible and invisible 'Berlin Walls' in China," he pointed out, referring in particular to the Great Firewall, but he was optimistic they would soon collapse.

"The times when rulers could control everything and silence the people are over," he said. "Social and technological progress are unstoppable."

He also added that the fact so many party functionaries were sending their children abroad was a sign that China's rulers themselves did not have so much faith in the system.

Moral support is essential

Apart from visiting the Berlin Wall, Chen met many German politicians during his stay, including the government's commissioner for human rights policy Markus Löning.

He warned the government against neglecting China's human rights in favor of economic interests and said there could be no long-term profits with a dictatorship.

"I escaped so I could tell the world about the situation in China," he pointed out.

"Although in the end, only the Chinese themselves can change the country, the moral support of the West is essential."