Free speech is not important because it is a pleasant experience to be able to speak your mind. It is important because it is the only hope we have of society making moral and intellectual progress. Every time a new idea comes along, it starts out unpopular and faces resistance from the establishment. If we decide what is right by arguing, unpopular but correct ideas can win. If we resort to blows, they are much less likely to.

The government must permit free speech because we cannot improve a system we cannot criticize. But this is not a sufficient condition to give new and radical ideas a chance. Citizens must believe in the principle, too. Just like all the anti-discrimination restrictions on government offer little protection to the marginalized when any business can do it, a guarantee that the government will not throw you in jail for your speech means little when no one will host your website, no one will print your book, no one will hire you, and campaigns of bullying and harassment are fair game.

It is easy to feel that might makes right when you are on the side of the majority, but looking back in history, it is not always obvious what is right. For example, we often imagine that the historical opposition to interracial marriage proceeded from base hatred, but this wasn't so. The science of the time showed clearly and repeatedly that the races had vastly differing intelligences and that intelligence was heritable. We know now that this research was flawed, but at the time, it was well established scientific opinion. The concern was that by mixing the races, we would drop the intelligence of humanity down to the mean, and deprive ourselves of great thinkers, and bring about the doom of humanity in an idiocracy. It was argued that those who supported interracial marriage were blinded by compassion and would cause the downfall of civilization.

This was a very popular, very intellectually credible view, held by good and responsible upstanding citizens who were willing to work hard and fight hard to protect civilization.

Sure, they were able to pass laws based on their views. That's right and proper. But should they have been allowed to suppress dissent? Should the scientific community have rejected research that would lead to the doom of human civilization? Should people be fired for supporting it? Demonstraters identified, shamed, and harrassed? Print shops refuse to print their literature?

The world is a weird place. Speech which we consider dangerous abnd abhorrent usually is. But sometimes? Sometimes it's right, either in part or in whole. Sometimes what you think is right, based on what you think you know, turns out to be wrong.

The reason it is critical to let Nazis speak, the reason it is critical to oppose arguments with arguments alone and never with any measure of force, is that this is the only system under which views which are true and right have a chance of winning.

Whatever you want the rule to be, however you want to treat the Nazis, remember that not that long ago, their ideas were the ones that were obviously popular and right, that all the well-informed and powerful and good people subscribed to.

The price of free speech is that there are always crazies. People starting cults of ignorance and hate, drawing the desperate and the damaged into them and threatening the very foundations of society. These ideas need to be fought, but it is crucial that they be fought WITH. WORDS. If we resort to collaborative blows, we will miss it when the crazies are right about something important.