VACLAV HAVEL was, in some respects, an unlikely revolutionary. He wasn’t much of an orator or particularly charismatic: He was shy, sometimes diffident, prone to speaking in philosophical abstractions or with an air of irony natural to a Central European intellectual. He was drawn to absurdist artists like Frank Zappa, and his own plays could be hard to follow. When he was not in prison, he lived in a huge apartment block with the name Havel chiseled over the entrance — the legacy of his bourgeois family.

Yet perhaps precisely because he was neither a rabble-rouser nor an ideologue burning with anger, Mr. Havel pioneered an entirely new form of political revolution — one that is as relevant in the tumultuous year of 2011 as it was when he first spelled it out in the mid-1970s. His simple but extraordinary idea was that the most effective way to defeat a totalitarian regime was for citizens to reject its lies and “live in truth.” That meant, first of all, telling the truth in answer to official propaganda, but also behaving as if fundamental human rights — which most dictatorships claim to respect — could be taken for granted.

This was a peaceful strategy but also one that required enormous courage. After writing his seminal essay “Power of the Powerless” in 1978, Mr. Havel spent nearly five years in prison, where his health was badly damaged. For 16 years afterward he suffered incessant monitoring and harassment from the secret police of Czechoslovakia, the most coldly repressive regime of the Soviet Bloc. He and the small band of dissidents who made up the Charter 77 movement were dismissed by most of their countrymen, and most of the outside world, as engaging but irrelevant dreamers.

The stunning success of the 1989 Czechoslovak “Velvet Revolution,” when the sight of massive crowds gathered in Prague’s Wenceslas Square prompted a rotting Communist bureaucracy to collapse, proved that Mr. Havel’s strategy could work. It also helped to establish a model that has spread around the world — to Serbia and Ukraine, Lebanon and Kyrgyzstan, and now — in another landmark year of revolution — Tunisia and Egypt. Such peaceful assertion of human rights doesn’t always succeed. Some rulers, such as Syria’s Bashar al-Assad, still respond with mass murder. In China, a movement modeled after Charter 77 and called Charter ’08 has been ruthlessly suppressed — for now — though its prime author, Liu Xiaobo, was awarded the Nobel Peace Prize.

Mr. Havel never received that award, but he didn’t seem to mind much. After his own nation’s fight for freedom was won, he reveled in fighting for others — including Mr. Liu, Burma’s Aung San Suu Kyi and the Dalai Lama of Tibet. Not all of his causes enamored him to Western liberals: He also worked assiduously for the opposition movement in Cuba, and he supported war in Iraq as “an act helping people against a criminal regime.” In his last days he tried to inspire the Russian opposition to Vladi­mir Putin — which, following his example, was peacefully insisting on its right to tell the truth to a government built on lies. He will be greatly missed — but the moral revolutions he conceived will go on.