Free speech is the cardinal right – the right that underpins all others. Yet how casually we brush it aside.

This week in Toronto, a small group held a memorial service at a public library branch for a lawyer who had defended Holocaust deniers and other figures on Canada’s far-right fringe. Spokesmen for Jewish groups said they were outraged that the Toronto Public Library would provide a platform for such a gathering. Mayor John Tory was “deeply concerned.” Members of city council said they were shocked. “Those tied to hate and bigotry have no place in our libraries,” Councillor James Pasternak said.

They seemed entirely oblivious to the threat to freedom of expression. If the library takes it upon itself to decide who has the right to speak, where does it end? If it denies space to a far-right group, what happens when a far-left group comes along? What would it say to the many Canadians who suffered under communism if someone who denies the crimes of Stalin or Mao wanted to hold an event and was denied? What would it say to Toronto’s large Tamil community if extreme Sinhalese nationalists were not permitted to hold a study meeting at the library about the crushing of the Tamil separatist movement in Sri Lanka?

Opinion: We need to protect free speech on campus

It is precisely to avoid making these judgments that the library takes a neutral approach to those who book its spaces. It doesn’t demand to vet their opinions in advance. As long as they follow basic rules of conduct, they get the space. So it is absurd to suggest that the library is somehow endorsing or countenancing the views of those who held this week’s memorial.

Critics of the event seem especially upset that it took place in a “public space,” under the roof of a publicly funded institution. It is not hard to see where that dangerous argument could lead. If people whose opinions are deemed beyond the pale are to be kept out of the public libraries, why not the public parks, the public squares, the public streets? Who gives them the right, some might say, to wave their nasty placards where all can see, or publish their rank opinions where all can read? Surely public spaces are where free speech, however outrageous or obnoxious, should be allowed to flourish. That is the principle behind the famous Speakers’ Corner in London’s Hyde Park, where people of every opinion and background get the chance to sound off in public. No one says that because the authorities allow it they are giving their stamp of approval to what is said.

Libraries, in particular, should be havens for free expression. They are the places citizens go to learn about the world in all its complexity. Librarians are always facing pressure from one group or another to ban books that they say might corrupt morals or spread hate. They are right to fend off such attempts. Librarians are guides to the world of knowledge, not arbiters of it. They should be equally impartial about who meets in library spaces.

Banning objectionable speech short of direct incitement to violence is always a mistake. Those who object to this week’s event and gatherings like it have other ways to respond. One is to protest. If a hate group holds a rally, hold a rally condemning hate and praising tolerance. Another is to correct. When deniers spout nonsense about how many died or didn’t die in the Holocaust, fight back with the undeniable facts.

The last option – perhaps the best when it comes to the tiny, miserable group of cranks who are Canada’s white nationalists and Holocaust deniers – is simply to turn away. They feed on publicity like this week’s fuss. Instead of fulminating against them or attacking the library for giving them space, ignore them. They don’t deserve even a minute of our time, much less all the air time and headline space they got this week.

No matter how we choose to respond to offensive opinions, it is important to remember the danger of suppressing them. Even in a blessed place such as Canada – a strong, stable democracy with a respected Charter of Rights and Freedoms – freedom of speech can be a fragile thing. We saw that just recently, when three editors left their jobs after an angry pile-on over the complicated issue of cultural appropriation.

In a 1945 essay on free speech and the profusion of it in Hyde Park, George Orwell wrote: “The relative freedom which we enjoy depends on public opinion. The law is no protection. Governments make laws, but whether they are carried out, and how the police behave, depends on the general temper of the country. If large numbers of people are interested in freedom of speech, there will be freedom of speech, even if the law forbids it; if public opinion is sluggish, inconvenient minorities will be persecuted, even if laws exist to protect them.”

On the evidence of the library affair and other events lately, public opinion in the Canada of 2017 is sluggish indeed.