By Dan Griffiths
BBC News, Beijing
Tuesday marks the 40th anniversary of the start of China's Cultural Revolution.
Images of Chairman Mao are everywhere
It began as an attempt by Chairman Mao to tighten his grip on power, but it soon turned to chaos.
Students and workers formed squads of radical Red Guards and went on the rampage. Many died in the ensuing violence and China was left in a state of anarchy for a decade.
So what do people in China think of the Cultural Revolution today?
Every year millions of tourists visit Beijing's Tiananmen Square. They come to look at the swooping golden roofs and red walls of the Forbidden City and to see Chairman Mao's mausoleum.
Watching them at play, it is hard to believe that on the same spot 40 years ago thousands of teenagers stood waving their little red books and swearing undying loyalty to Chairman Mao.
But many here in China live with the memory of those chaotic years every day of their lives.
Just a short walk from Tiananmen Square is Jingshan park. It used to be the emperor's private garden but now it is where some of the city's retired go to sing the old revolutionary songs and do their morning exercises.
There I met writer Dai Qing. During the Cultural Revolution one of her relatives was buried alive by Mao's Red Guards.
"I can never forget what happened then," she said. "No-one can ever forget".
She wants China's ruling Communist Party to have a public inquiry. "Only when we can tell all the stories of that time, without censorship, only then will we know what happened and why it happened," she said.
But she will have to wait a long time. The Cultural Revolution was a disaster for the authorities - a time when they lost control of Chinese society. They have banned any public debate on the era.
Looking to the future
Tiananmen Square holds many memories of the Revolution
And not everyone who lived through the Cultural Revolution wants to re-examine the past.
Take the case of Hao Jiangtian. He is one of the New York Metropolitan Opera's superstars. But he grew up in China during the Cultural Revolution when classical music was considered capitalist and decadent.
His piano teacher was thrown into prison. His musician parents destroyed all their classical records to avoid the same fate, and many of their colleagues committed suicide.
But now it is not the past he wants to talk about but the future. He says that since the Cultural Revolution, millions have started to study music in China and he is playing a key role in helping them develop their talents.
And it is not just Hao Jiangtian who is looking forward.
There is a whole generation here in China who were born after the Cultural Revolution.
Beijing University was a hotbed of activity during the early days of the Cultural Revolution but now students like Vivian and Shirley have other things on their minds.
China's economy is one of the world's fastest growing
"Today people aren't very interested in politics" Vivian told me. "They are thinking about other things like their futures and travelling overseas."
Shirley said there could never be another Cultural Revolution now.
"China has opened up to the world and now we are part of the world economy, we don't want collectivism any more, we want individualism."
Vivian and Shirley are part of the new generation in China who want good jobs and a comfortable lifestyle. For them the Cultural Revolution now means very little.
And perhaps that is just what the Communist Party wants. But for Dai Qing and millions of Chinese like her, it is a time they will never forget.