WASHINGTON—As I was watching “The Lives of Others,” Florian Henckel von Donnersmarck’s masterful Oscar-winning film, I couldn’t help thinking how many Cubans, North Koreans, Iranians or Zimbabweans must have been performing little bits of moral heroism in the face of oppression at that very moment. Even their fellow countrymen will never know how many acts of defiance are being perpetrated today by ordinary people against totalitarian regimes—ensuring that the human spirit continues to exist when everything seems bent on crushing it.

The German film focuses on Gerd Wiesler, a captain in the Stasi, East Germany’s feared secret police, five years before the fall of the Berlin Wall. He is ordered to spy on a playwright and his actress girlfriend simply because the minister in charge of culture lusts for the lady and needs an excuse to put the writer away in order to clear the path. Through a tantalizing series of small twists and turns in which what is not said is more important than what is, the plot leads us toward the moral awakening of Wiesler. As he records the details of the playwright’s and his girlfriend’s lives, the gray, obedient bureaucrat discovers in himself a humane depth to which nothing in his ideological rigidity or in the chilling machinery he efficiently serves seemed to predispose him. This moral awakening is intimate and unassuming, and it leads Wiesler to an act of quiet heroism that will save his intended victim from the fate that the minister wishes for him without leaving traces or claiming credit for his actions later on.

What “The Lives of Others” reminds us of—and the reason why it is such a timeless work of art—is that man is capable of totalitarianism, but not perfect totalitarianism. Even when all the pegs are in place, something will alter the clockwork mechanism of the regime. That “something” is human nature, pure and simple. Nobody in the film is a perfect totalitarian in the sense that no one—not the bosses, not the servants, not the victims—acts in the way that the logic of the system dictates they should act in any given circumstance. There will be moments of weakness in the least humane of despots and moments of fortitude in the most hopeless victims that will shatter the perfect order of the totalitarian system.

The minister who uses the power of the Stasi to satisfy his libido rather than to preserve the German Democratic Republic’s ideological purity, and who blacklists a theater director for reasons that have little to do with cultural orthodoxy, ensures that the system is less than perfect: His actions have consequences that in small ways subvert the order he is supposed to preserve by triggering the gradual disobedience of a subordinate, the moral awakening of an artist who has shown no prior penchant for rebellion, or the self-doubt of a woman torn between her career and her heart. Emotions, intuitions, and free expressions of will begin to erode the edifice of oppression in the most unpredictable circumstances.

Those cracks that open up in the system seem insignificant when they occur, but we now know what East Germans did not know in 1984: that five years later the Berlin Wall would crumble to bits. A few weeks ago, Cuban poet Cesar Lopez, a darling of the Castro regime, used the podium at an international book fair on the island to acknowledge a long list of Cuban writers who have been banned for years. He did not attack the government; he simply read aloud the blacklisted names with a tone of recognition.

The lesson of our time, a decade and a half after the fall of communism in Europe, is that the slow, almost geological, accumulation of little bits of heroism throughout society can bring down a totalitarian giant over time. These acts of heroism, both inside and outside the structure of power, constitute the best hope for countries in which governments continue to enslave millions of people today.

But even if these acts of silent heroism are not enough to cause all despots to come tumbling down, they are at least enough to keep the human spirit alive. That is a comforting thought.