Image copyright ALAMY Image caption Dustin Hoffman as Lenny Bruce in the 1974 film Lenny

Self-censorship can be as much a threat to free speech as its government equivalent, argues Roger Scruton.

Any discussion of free speech needs to deal with two important issues - jokes and race. Jokes are not opinions, but they can cause just as much offence. So should there be the same freedom to make jokes as to express opinions?

The issue of race has been the subject of deep self-questioning in modern communities. The most horrible genocide in recent history - the Holocaust - occurred because people felt free to hate the Jews and to broadcast that hatred in speech that was protected by law. The oppression of black people in America and their exclusion from the privileges of citizenship was advocated freely and destructively throughout recent times. And again the opinions were protected by law. Don't these and similar cases justify the current belief that free speech is not a good in itself, and that groups liable to be targeted by collective hatred should be protected from its abuse?

These two issues are of pressing concern to us. The Charlie Hebdo affair in France reminds us that jokes can give such offence as to inspire the most violent response to them. And we should surely not be surprised if the French comedian Dieudonne, who regularly includes anti-Semitic jokes in his stand-up shows, is now banned from many places in France and Belgium.

Image copyright Getty Images Image caption Controversial French comedian Dieudonne

We should remember, however, that offence can be taken even when it has not been given. There are radical feminists who search every innocent remark about women for the hidden sexist agenda. Even using the masculine pronoun in the grammatically sanctioned way, so as to refer indifferently to men and women, can cause offence and is now being banned on campuses all across America. It is not that you wish to give offence. But you are up against people who are expert in taking it, who have cultivated the art of taking offence over many years, and who are never more delighted than when some innocent man falls into the trap of speaking incorrectly.

Find out more Roger Scruton is a writer and philosopher

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Typically a joke tries to cut things down to size, so that you can feel at ease with the thing you laugh at. Most ethnic jokes are like that - ways of dealing with ethnic diversity, by helping people to feel content with their own group, and not threatened by the others. Sometimes it is your own group that is cut down to size - as in the many Jewish jokes that show some Jewish foible to be an amusing eccentricity rather than a threat. Jokes become popular because they soften things, making reality, with all its divisions, less of a threat. Here is a well-known joke from the Northern Ireland troubles - one man stops another in the street and points a gun at his chest. "Catholic or Protestant?" he demands. "Atheist," comes the reply. To which the response is "Catholic atheist or Protestant atheist?" Humour of that kind is pointing both to the absurdity of sectarian conflict, and also to the fact that it is a pretence, an excuse for hatred rather than a response to it. It is reminding us that the art of taking offence is used by small-minded people to gain an unwarranted advantage over the rest of us.

Of course there are jokes in bad taste, jokes that express unpleasant or malicious attitudes. We teach our children not to tell jokes of that kind, and not to laugh when others tell them. Humour is informed by moral judgment. We hope to turn it towards acceptance and forgiveness, and away from malice and contempt. But how should we deal with the joke that gives offence?

You cannot legislate against offence. No legislation, no invention of new crimes and punishments, can possibly introduce irony, forgiveness and good will into minds schooled in the art of being offended. This is as true of radical feminists as of sectarians and radical Islamists. While we have a moral duty to laugh at them, they have also made it dangerous to do so. But we should never lose sight of the fact that it is they, not we, who are the transgressors. Those who suspect mockery at every turn, and who react with implacable anger when they think they have discovered it, are the real offenders.

So what about racist speech? Is this any different from the other kinds of protected speech, or is there some special reason for criminalising it? Does the Holocaust justify banning the opinions that gave rise to it? Many people think so, and in France the legislature has gone further and criminalised those who deny that the Holocaust occurred.

Image copyright Sean Gallup Image caption The Berlin Holocaust memorial: Should denial of the event be punishable by law?

Racist opinions won't go away just because we forbid their expression. Indeed, forbidding them may give them a special allure. What was most destructive about the Nazi propaganda against the Jews was not so much the expression of those nasty opinions, but the suppression of those who sought to refute them. It was the lack of free speech that allowed the opinions to rampage out of control, free from the arguments that would have exposed them to ridicule. By contrast, black people in America earned their status as equal citizens partly because of free discussion, which persuaded ordinary Americans that racial stereotyping is both irrational and unjust. It is because they gave voice to their opinions that the racists were defeated.

The case is of vital importance to us in Britain. The policing of the public sphere with a view to suppressing "racist" opinions has caused a kind of public psychosis, a sense of having to tiptoe through a minefield, and to avoid all the areas where the bomb of outrage might go off in your face. And this bomb has been planted and primed by people many of whom see the accusation of racism as a useful way to undermine our belief in our country and its way of life. Hence police forces, public officials, city councillors and teachers have hesitated to think what they know to be true, or to act against what they know to be wrong. We have seen this in the cases of sexual abuse in Rotherham and elsewhere. when reluctance to single out an immigrant community for blame has been one reason for failing to act. My recent novel The Disappeared is an attempt to explore the depths of the moral disorder that has entered our society, through this kind of self-censorship, which prevents a teacher, a police officer or a social worker from acting, precisely when most sure that he or she must act.

Self-censorship is even more harmful than censorship by the state. For it shuts down the conversation completely. Because of mass migration our society has undergone vast and potentially traumatic changes, but without the benefit of public discussion, and as though we had no choice over our future. The depths of confusion and resentment are beginning to be perceivable, not only here but all across Europe, and it is discussion alone that would have prevented them. Those who have tried to initiate that discussion have been subjected to witch-hunts and character assassination of a kind that few people can easily endure. The result has been a loss of reasoned argument in places where nothing is needed so much as reasoned argument.

Image copyright PA Image caption 2013: Cambridge students protest against the appearance of right-wing French politician Marine Le Pen at the university's debating society

One last word about the art of taking offence. Nowhere has this art been more assiduously cultivated than on American campuses, where an entirely new culture of trepidation has set out to capture the adolescent psyche. When discussing any of the matters in which the secular dogmas have staked a claim - race, sex, orientation, sexual politics - the professor may now be required to issue "trigger warnings", lest he stray into areas that might trigger the memory of some traumatic event in the life of the student. Visiting speakers with heretical views about feminism or homosexuality are also preceded by trigger warnings. Some campuses even provide safe rooms where the trembling students can retire for consolation should they have been exposed to the contamination of an unorthodox point of view.

Amusing though this is, you have to be careful not to laugh at it, at least if you are a professor who has not got tenure. Those who wish to maintain the student mind in a condition of coddled vulnerability, unhardened by opposition and unpractised in argument, now police the campus, with the result that these places which should have been the last bastion of reason in a muddled world, are instead the places where all the muddles come home for nourishment. The example vividly illustrates the way in which the attacks on free speech can go so far as to close off the route to knowledge. And in the end that is why we should value this freedom, and why John Stuart Mill was so right to defend it - as fundamental to a free society - without it we will never really know what we think.

A Point of View is broadcast on Fridays on Radio 4 at 20:50 GMT and repeated Sundays 08:50 GMT

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