HONG KONG — The Chinese government tried to silence Liu Xiaobo by banning the publication of his writing, barring him from public speaking and locking him behind bars. But much of his work has been published overseas. It reveals Mr. Liu as a staunch advocate of democratic change in China who could be harshly critical of the country’s political authorities, some of its more celebrated writers and even, at times, himself.

Mr. Liu, who died Thursday, was a passionate and acerbic lecturer and literary critic in Beijing in the 1980s. He emerged as an influential figure in the 1989 pro-democracy movement. On June 2, two days before the military crushed the demonstrations in Tiananmen Square, Mr. Liu and three friends began a hunger strike. They declared:

We advocate the spread of democracy in China through peaceful means, and we oppose violence in any form. At the same time, we are unafraid of violence. Our aim is to show through peaceful means how the iron resolve of Chinese people who want democracy will in the end demolish an undemocratic order that maintains itself with bayonets and lies. (Translation by Perry Link in “No Enemies, No Hatred”)

Mr. Liu was the primary force behind the Charter 08 manifesto, which called for political changes to democratize China. The document, which was initially signed by hundreds of Chinese intellectuals, led to his arrest in December 2008. On Dec. 25, 2009, he was sentenced to 11 years in prison for “inciting subversion of state power.” Charter 08 read, in part:

China, as a major nation of the world, as one of five permanent members of the United Nations Security Council, and as a member of the U.N. Council on Human Rights, should be contributing to peace for humankind and progress toward human rights. Unfortunately, we stand today as the only country among the major nations that remains mired in authoritarian politics. Our political system continues to produce human rights disasters and social crises, thereby not only constricting China’s own development but also limiting the progress of all of human civilization. This must change, truly it must. The democratization of Chinese politics can be put off no longer. (Translation by Perry Link)

During his trial, Mr. Liu defended Charter 08, saying it accurately described events such as the Anti-Rightist Campaign of the late 1950s, the Great Leap Forward of 1958-61, the Cultural Revolution and the Tiananmen crackdown of June 3-4, 1989.

First, the “human rights disasters” mentioned in Charter 08 are all facts that have occurred in contemporary China: the Anti-Rightist Campaign wrongly labeled more than 500,000 people as rightists; the Great Leap Forward caused the unnatural deaths of as many as 10 million people; the Cultural Revolution created a national catastrophe. June 4th was an act of murder during which many people died, and many were thrown into jail. These facts are all universally acknowledged “human rights disasters” that indeed brought on crises in China’s development. ... Second, the long-term objective of the values declared and political reform proposals raised in Charter 08 is the establishment of a free and democratic federal republic. It contains 19 reform measures and advocates a gradual and peaceful approach to reforms. In view of the various malpractices of the current lame-duck reform, it requests that the ruling party transform the lame foot into a second leg, namely, that it advance political and economic reforms together in harmony. ... Third, in the past two decades, from 1989 to 2009, I have always expressed the view that China’s political reforms should be gradual, peaceful, orderly, and controlled. I have also consistently opposed quick one-leap radical reforms, and even more so violent revolution. (Translation by Human Rights in China)

In 2010, Mr. Liu was awarded the Nobel Peace Prize. When he learned the news during a prison visit from his wife, Liu Xia, he cried and dedicated the prize to the people killed during the 1989 military crackdown. Mr. Liu was credited with saving many lives when he helped negotiate a retreat of protesters as soldiers advanced on Tiananmen Square. The bloodshed of the crackdown, in which hundreds and possibly thousands of people were killed, gave him a profound focus and a lasting sense of guilt, something he addressed in an essay in 2003:

That bloody dawn in 1989 ... showed me how shallow and self-centered I still was, taught me to recognize the warmth and the inner strength of love, and gave me new appreciation of what is most important in life. I knew from that time on I would forever be living with the guilt of a survivor and in awe of the souls of the dead. (From “Using Truth to Undermine a System of Lies,” 2003. Translation by Eva S. Chou in “No Enemies, No Hatred”)

Chinese state news outlets criticized Mr. Liu, particularly after the Nobel Prize, for his previous writings and interviews that praised the West over China. In one oft-quoted passage from a 1988 interview with Open Magazine in Hong Kong, then a British colony, he said that since the city had progressed so much during 100 years of British rule, China would “need 300 years of colonialism” to catch up. But in later work he expressed second thoughts. In the epilogue to his 1990 book “Chinese Politics and China’s Modern Intellectuals,” he wrote:

My tendency to idealize Western civilization arises from my nationalistic desire to use the West in order to reform China. But this has led me to overlook the flaws in Western culture — or, even if I see them, to set them aside intentionally. I have not, therefore, been able to stand apart from Western culture, take a critical view of it and perhaps get a better view of human frailty more generally. I have been obsequious toward Western civilization, exaggerating its merits, and at the same time exaggerating my own merits. I have viewed the West as if it were not only the salvation of China but also the natural and ultimate destination of all humanity. (Translation by Stacy Mosher in “No Enemies, No Hatred”)

Because Mr. Liu remained in prison after he was selected for the Nobel in 2010, he was represented at the award ceremony by an empty chair. His lecture, which was read by the Norwegian actress and director Liv Ullmann, was the statement he had prepared for his 2009 trial. “I Have No Enemies: My Final Statement” describes Mr. Liu’s love for his wife, Liu Xia, his lack of enmity toward the police and prosecutors who put him behind bars, and his hopes for political liberalization in China: