In On Tyranny, Timothy Synder offers 20 lessons, developed in 20 short chapters. Each lesson consists of an imperative statement to the reader, followed by a concise explanation and then one or more examples. The examples come almost entirely from 20th-century European history and recent developments in the United States. The book urges citizens of the United States to recognize an impending threat of tyranny and try to defend democracy and freedom before an authoritarian regime can damage the government.

The first two lessons, “Do not obey in advance” and “Defend institutions,” use examples from the rise of the Nazi Party before World War II. The Nazis were able to destabilize Germany’s existing system of government and laws so that they could create a fascist dictatorship. The third lesson, “Beware the one-party state,” describes how several different European nations went from electoral democracies to dictatorships. The people in each country were probably unaware that they were voting for the last time. While most of the new regimes did not last, the lapses into dictatorship might have been avoided if citizens had heeded the warning signs. The fourth lesson, “Take responsibility for the face of the world,” instructs the reader to fight back against symbols of hate and labels that denigrate certain groups of people. Any social outgroup can quickly become a “them” that threatens “us.”

The fifth lesson, “Remember professional ethics,” discusses the professional occupations that could have resisted fascist regimes by following their own codes of ethics. Lawyers, doctors, and businessmen were all instrumental in the installation and continued operation of Nazi concentration camps. Lesson 6, “Beware of paramilitaries,” warns the reader that fascist regimes often employ military personnel who are not part of the nation’s military, including personal bodyguards and secret police. Lesson 7, “Be reflective if you must be armed,” asks military and law enforcement members to consider their actions carefully. Most authoritarian regimes rely on local law enforcement and common soldiers to suppress resistance and silence any opposition. The eighth lesson, “Stand out,” encourages the reader to fight back against oppressive governments and laws however they can.

The next three lessons address issues that have arisen out of modern technology. Lesson 9, “Be kind to our language,” asks the reader to avoid repeating Internet rumors and to avoid adopting political slogans and catchphrases. Lesson 10, “Believe in the truth,” encourages the reader to verify everything that they read and hear, especially if it seems to have a bias. In the 21st century, news outlets have pushed narratives that appeal to personal beliefs and emotions instead of relaying facts and letting the audience decide how to respond. Ignoring facts and trying to persuade the public through emotions are the tools of a future tyrant. Lesson 11, “Investigate,” expands on the previous lesson and suggests that everyone should be critical consumers of news media. This also means that regular citizens should be wary of politicians who denounce journalists or limit news outlets.

Lesson 12, “Make eye contact and small talk,” encourages people to interact more with their neighbors and peers in person, instead of immersing themselves in online content that will only reinforce their beliefs. Face-to-face interactions are more likely to challenge one’s own opinions with alternate perspectives. Lesson 13, “Practice corporeal politics,” encourages people to get involved with politics or other organizations. Lesson 14, “Establish a private life,” states that totalitarian regimes will always try to remove the barrier between public and private. The lesson also points out that no person could survive having their private life scrutinized in public, which is why the elimination of privacy is a common weapon of such regimes.

Lesson 15, “Contribute to good causes,” asks the reader to contribute to and join community-building organizations, whether political, charitable, or otherwise. Tyrannical regimes will try to convert such organizations into centers that further the regime’s goals. Extending this concept abroad, Lesson 16, “Learn from peers in other countries,” asks readers to make friends with citizens of other countries and to pay attention to media sources from outside one’s own country.

Lesson 17, “Listen for dangerous words,” reiterates some of the ideas from earlier lessons, and explains the danger that political slogans and patriotic vocabulary can present. By labeling certain groups as extremist or terrorist, a tyrannical government can encourage the public to attack them. Lesson 18, “Be calm when the unthinkable arrives,” explains that tyrants often seize on natural disasters or other crises to declare martial law or otherwise limit people’s individual freedoms. Many people will accept the limitations in the belief that they are necessary, not realizing that an authoritarian government has no plans of restoring the lost freedoms later.

Lesson 19, “Be a patriot,” draws a distinction between patriotism and nationalism. Patriots have ideals and values that they believe will improve the country, while nationalists will abuse the law and the truth to create narratives that serve their purposes. Lesson 20 is simply a statement: “Be as courageous as you can.” No examples or explanation follow.