The Limits of Tolerance

Why It Matters

The paradox of tolerance is not a rhetorical trick — it is a genuine philosophical problem that democratic societies have been grappling with since Weimar fell. Post-war West Germany banned the Nazi Party and made Holocaust denial a crime. The European Court of Human Rights allows member states to restrict speech that promotes hatred against groups. The United States takes a more absolutist position, protecting even most hate speech under the First Amendment. All of these are responses to the same problem, and none of them has cleanly solved it.

The stakes are real on both sides. If a tolerant society refuses to defend itself against genuinely anti-democratic movements, it may fall — as Weimar fell. If a tolerant society grants the state broad authority to suppress 'intolerant' movements, that authority will inevitably be used against legitimate dissent — as happened in every country that has built robust speech restrictions. The history of 'hate speech' laws shows that they are frequently applied against minority communities rather than in their defense. The history of 'national security' exceptions to free speech shows that they are frequently used to suppress antiwar and labor movements. The danger of unlimited tolerance is real. The danger of the solution is also real.

This is a lesson where the honest answer is 'this is genuinely hard and you should be suspicious of anyone who tells you it isn't.' The goal is not to arrive at a formula but to understand the structure of the problem well enough to evaluate specific cases with appropriate nuance.

A Story

A Dialogue on the Limits of Tolerance

The following is a composite dialogue drawing on arguments actually made in the philosophical and historical literature. The two speakers — Phoebe and Marcus — are not strawmen. Both are making the best version of their respective arguments.

Phoebe: I've been reading Popper, and his paradox seems obviously right. If you let people who want to destroy democracy use the freedoms of democracy to do it, you'll lose democracy. Weimar let Hitler organize, campaign, and get elected. The result was the Holocaust. Surely unlimited tolerance is just suicide.

Marcus: I agree with the historical observation but I worry about the principle you're drawing from it. Once you establish that the state can suppress movements it labels 'intolerant,' you've created a power that will be used. The question is: used by whom, against whom? McCarthy used national security exceptions to destroy the careers of labor organizers and leftists who had nothing to do with Soviet espionage. Jim Crow laws were enforced partly through laws against 'sedition' — meaning Black civil rights organizing. Every time a society says 'this movement is so dangerous that normal rights don't apply,' the people in power get to define what's dangerous.

Phoebe: That's a real risk, but it doesn't defeat the principle. It means we should be careful about how we implement the principle — we should require a very high standard of evidence before any suppression — but it doesn't mean the principle is wrong. A movement that openly states it intends to seize power and abolish elections isn't just a disagreeable political party. It's something qualitatively different.

Marcus: I agree that something qualitatively different is going on when a movement explicitly rejects the rules of the game rather than just playing the game badly. My worry is about who decides when that line has been crossed. You said 'openly states' — but most movements that are actually dangerous don't openly state their goals. They use normal political language while pursuing anti-democratic ends. And once you allow 'they didn't say it explicitly but we know what they really mean,' you've given enormous discretionary power to whoever controls the standard.

Phoebe: So what's your alternative? Just let every anti-democratic movement do whatever it wants and hope the voters reject it?

Marcus: No. I think there are things a tolerant society can and should do. It can prosecute actual violence and incitement to imminent violence — that's a well-established, well-cabined exception. It can refuse to grant state resources to anti-democratic movements. It can educate citizens about the tactics of such movements. What it probably shouldn't do is suppress political speech based on content — based on what ideas are expressed — because that power will be misused. The solution to political extremism is primarily political, not legal.

Phoebe: What Popper actually wrote is more careful than the way people quote him. He said: 'We should therefore claim, in the name of tolerance, the right not to tolerate the intolerant.' But he also said that the suppression should be used only as a last resort — that we should first try to counter intolerant speech with rational argument, and only move to legal suppression if that fails. Which implies that the default is engagement, not suppression.

Marcus: That's the version I can live with. And it requires something harder than just banning things: it requires actually engaging with the arguments of people you find dangerous — understanding why people are attracted to them, making a better case for the open society. That's much harder than a ban. But it's probably more durable.

Vocabulary

Paradox of tolerance

Karl Popper's observation, from The Open Society and Its Enemies (1945), that unlimited tolerance is self-defeating: a society that tolerates even movements committed to destroying tolerance will eventually be destroyed by them. Often cited as a justification for restricting intolerant speech or movements, though Popper himself set a high bar for when suppression was warranted.

Militant democracy

A constitutional design, adopted by West Germany after 1945, in which democratic institutions are explicitly empowered to defend themselves against anti-democratic movements. The Basic Law allows the banning of parties that threaten the constitutional order. A direct institutional response to the Weimar failure.

Incitement

Speech that is intended to produce, and is likely to produce, imminent unlawful action. Distinguished from mere advocacy of unlawful action. The standard established by the U.S. Supreme Court in Brandenburg v. Ohio (1969) for the narrowest category of speech that loses First Amendment protection.

Chilling effect

The deterrence of legitimate speech by the threat of legal sanction. When speech restrictions are broad or vaguely defined, people self-censor beyond what the law formally requires, because the risk of being prosecuted feels too high. A key argument against broad hate speech laws: they chill more legitimate speech than they suppress harmful speech.

Open society

Popper's term for a society characterized by freedom of inquiry, criticism, and political change through non-violent means. Contrasted with 'closed societies' that enforce orthodox belief and suppress dissent. Popper argued that the open society was fragile precisely because it extended freedoms that could be exploited to destroy it.

Guided Teaching

Begin with Popper's actual text. Many students will have encountered the paradox in a truncated form — 'you don't have to tolerate intolerance' — which omits Popper's crucial qualifications. Read the actual passage with your student: Popper was explicit that suppression should be a last resort, that rational argument should be the first response, and that legal suppression was warranted only when movements 'forbid their followers to listen to rational argument' and use violence to spread their teaching. Ask: 'Does the truncated version of the paradox match Popper's actual position? What is lost in the shortening?' The point is not pedantry but a demonstration that complex arguments are regularly simplified in ways that change their meaning.

The historical record of speech restrictions cuts against comfortable assumptions on both sides. On the one hand: Weimar's failure to suppress the Nazi Party before it took power is a genuine historical argument for limits on tolerance. On the other hand: every major democratic country that has built broad hate speech or 'dangerous speech' laws has a documented history of applying those laws against the communities they were ostensibly designed to protect. Canada's hate speech laws have been used against a gay rights activist who criticized religious opposition to homosexuality. Germany's Nazi propaganda laws have been applied against Muslim preachers in ways the original drafters did not anticipate. Ask: 'Does the history of misapplication defeat the case for speech restrictions, or does it simply argue for more careful drafting?' There is no clean answer.

The 'who decides?' problem is structurally unavoidable. Every approach to the paradox of tolerance requires someone to decide which movements are sufficiently intolerant to warrant restriction. That authority, once granted, will be exercised by whoever holds power — and whoever holds power has interests. Ask: 'If you support giving the government the power to restrict intolerant movements, are you comfortable with this government — whichever government is in power when you're not — exercising that power?' The thought experiment of imagining the same power in the hands of your opponents is one of the most useful tools in constitutional design. Rights should be designed for the whole distribution of possible governments, not for an idealized version of the current one.

What Popper's framework actually requires is harder than suppression. If the default response to intolerant movements is rational argument — engagement rather than ban — then the open society requires its citizens to be genuinely capable of making the case for openness, and making it well. This is not a comfortable demand. It requires understanding why intolerant movements attract followers, what needs they address, and what the open society is offering in their place. Ask: 'Have you ever thought about why authoritarian movements appeal to people? Not the obvious explanation — that people are stupid or evil — but the real underlying needs and grievances that make such movements attractive? And if you can't answer that, what does it say about your ability to counter them?'

End with the reflexive version. Ask: 'The concept of 'intolerance' can itself be weaponized — applied to any movement you want to suppress, regardless of whether it actually threatens the democratic order. How would you distinguish between a movement that is genuinely anti-democratic and one that is merely offensive to powerful people? What is the test?' This is the hardest question in the lesson and probably the one that does not have a satisfying answer. But pressing students to articulate a test — even an imperfect one — is more valuable than leaving the question abstract.

For Discussion

1. 1.Popper said suppression should be a last resort. What does a 'first resort' of rational argument actually look like when a movement rejects rational argument by definition?
2. 2.Post-war West Germany banned the Nazi Party and made Holocaust denial a crime. The United States allows neo-Nazi marches and Holocaust denial. Both are functioning democracies. What does this difference in approach tell you about the range of defensible responses to the paradox of tolerance?
3. 3.The history of speech restrictions in democratic countries shows they are frequently applied against minority communities rather than in their defense. Does this pattern argue for abandoning speech restrictions, or for designing them more carefully?
4. 4.If you cannot answer the question 'why do authoritarian movements attract people?' does that limit your ability to counter them? What does a genuinely effective response to political extremism require?
5. 5.Is there a version of the 'paradox of tolerance' argument that you would find convincing as applied to a movement you personally disagree with? Is there a version you would find convincing as applied to a movement you personally support? What does the difference tell you?

Practice

The Standard: Drafting a Principle

1. 1.Your task is to draft a principle — as precise as possible — that specifies when a democratic society may restrict a political movement on the grounds of that movement's threat to democracy.
2. 2.Your principle must answer all of the following questions:
3. 3.1. What specific characteristics must a movement have before restriction is warranted? (Not just 'intolerant' — that's too vague. What specifically must it claim or do?)
4. 4.2. What form may the restriction take? (Banning the party? Restricting certain speech? Denying state resources?)
5. 5.3. Who decides whether a movement meets the standard? What process governs that decision?
6. 6.4. What protections exist against misuse of the standard?
7. 7.After drafting the principle, apply it to two test cases: (a) the German Nazi Party in 1932, and (b) a movement in a country of your choosing that some people consider anti-democratic and others consider legitimate.
8. 8.Discuss with a parent: Does your principle work cleanly on both cases? If not, what does it need to say that it currently doesn't? And: is it possible to write a principle that is both effective against genuine threats and immune to weaponization? Why or why not?

Memory Questions

1. 1.What is Popper's paradox of tolerance, stated precisely?
2. 2.What did Popper say should be the first response to intolerant movements, before legal suppression?
3. 3.What is 'militant democracy,' and which country adopted it after 1945?
4. 4.What is the 'chilling effect,' and why does it matter for evaluating speech restrictions?
5. 5.What is the 'who decides?' problem, and why is it structurally unavoidable in any approach to the paradox of tolerance?