Trigger Warning (noun): a statement at the start of any piece of writing, video, etc, alerting the reader or viewer to the fact that it contains material they might find upsetting or offensive.

Trigger Warning is a long and fierce defence of the right to unrestricted freedom of speech including “hate-speech”. A rich resource, it contains nearly all of the key cases and quotations you’ll need to understand this extremely difficult issue. It’s also highly repetitive, and few will finish it in its present form. Mick Hume should hire an implacable copy editor, cut the book by 100 pages in an immediate second edition and spin off a separate incandescent pamphlet (50 pages maximum) aimed at achieving the kind of sales Harry Frankfurt enjoyed with On Bullshit.

I hope he will, because the wide circulation of Trigger Warning could do some good. It’s a polemic, but might calm us down. We need something like this, because the “moronic inferno” of the media (Saul Bellow’s phrase) has grown more intense over the last 20 years and has become more malignant. It caters increasingly to what personality psychologists call “the Dark Tetrad”: sadism, Machiavellianism, psychopathy and narcissism (these traits have been shown to be strongly linked to internet trolling). We’re surrounded by outrage-junkies – a snarling festival of mutual intolerance. The public air is poisoned by identity politics, rampant tribalism related to ethnic or religious identity, based on sexual preference, sexual equipment, disability, national identity, which football team you support, hair colour.

It’s hard to shut the problem out. The words of Tom Lehrer’s 1965 song “National Brotherhood Week” (“Oh, the white folks hate the black folks, / And the black folks hate the white folks / To hate all but the right folks / Is an old established rule … Oh, the Protestants hate the Catholics, And the Catholics hate the Protestants, And the Hindus hate the Muslims, And everybody hates the Jews … ”) aren’t more accurate now than when they were written, but there are new hatreds, and we are constantly confronted by them.

What should we do? Hume thinks we have to put up with them. We human beings love to jeer and disparage. So be it; we can’t weaponise our repulsion. The worst are full of passionate intensity, as WB Yeats observed; but speech must be free. “One man’s vulgarity is another’s lyric,” as US supreme court Justice Harlan pointed out in 1971 when he reversed the conviction of a man for wearing a jacket reading “Fuck the Draft” in the corridors of a California courthouse.

Hume quotes Oliver Wendell Holmes Jr, another US supreme court justice: we have above all to defend “freedom for the thought that we hate”. He also quotes Spinoza: “In a free state, every man may think what he likes and say what he thinks.” (Spinoza is himself quoting a passage from Tacitus – “the rare happiness of times when you can think what you like and say what you think” – that David Hume used as the epigraph to his Treatise of Human Nature.) Mick Hume thinks this freedom is in danger. University campuses in particular have become petri dishes of intolerance, dictating what we can and can’t say. But we have to take it. We have to put up with the worst people saying the worst – ignoble, repellent, ignominious – things. We have to be constantly ashamed of our species.

The price is high. It must be paid, but I think Hume underestimates it. He reproduces a famous sentence from Evelyn Hall’s book The Friends of Voltaire that is often mistakenly attributed to Voltaire – “I disapprove of what you say, but I will defend to the death your right to say it” – and calls his enemies “the reverse-Voltaires, whose slogan is, ‘I know I will detest what you say, and I will defend to the end of free speech my right to stop you saying it’.” I’m not a reverse-Voltaire, but I’m something just as bad, in Hume’s typology: a “but-head”, someone who says, “I believe in freedom of speech, but … ” Anyone who says “but” must deny that the right to free speech is “indivisible”. Hume thinks that’s a fatal mistake: if you allow any exceptions, the dividing line between permitted and forbidden is no longer perfectly sharp, and you’re on a slippery slope, risking more and more restrictions. I disagree: the line is no longer sharp, but it’s not true that we’re on a slippery slope. The first amendment of the US constitution states categorically that “Congress shall make no law … abridging the freedom of speech, or of the press” (Hume calls it “the global gold standard” of free speech). The court’s defence of the first amendment over the years shows how the line can be held even after exceptions are allowed, for it does place limits on free speech – for example, on “fighting words”, deliberately intended and likely to incite “imminent lawless action”; on explicit threats against specific targets; and on false shouts of “Fire!” in a crowded theatre.

Hume admits these exceptions to unrestricted free speech, and then makes a rationalisation that he condemns elsewhere: he says they’re “not cases of free speech”, “not about free speech at all”. Yet each states quite plainly and correctly that you can’t say what you like, where you like, when you like: they place a limit on speech.

So Hume is himself a “but-head”, rightly so. And his admiration for the first amendment requires him to address an issue he omits: the fact that it was used to justify Citizens United, the 2010 US supreme court ruling that opened the way for corporations to contribute unlimited funds to political causes, and, in effect, buy the leaders they want, most notably by funding political “attacks ads” on television. Here free speech is free speech for the rich and, by the same token, the silencing of the poor. For while the poor can say and publish what they want, they will not be heard by the mass of the electorate. Hume criticises the UK Communications Act 2003 on free-speech grounds, but in this case it does more for the cause of free speech than the first amendment, by prohibiting political advertising on television or radio and ensuring equality of air time (mercifully brief) for the major parties’ party political broadcasts.

Hume may be right that, in addition to this act, a number of laws recently enacted in the UK – the Public Order Act 1986, the Racial and Religious Hatred Act 2006, the Terrorism Act 2006, the Criminal Justice and Immigration Act 2008 – contain sections that wouldn’t stand up if tested against the first amendment.

He thinks we should never flinch at words, but I don’t think he understands their force. When I set out for the Middle East, aged 16, I met up with a friend who was then living in a Christian community in Switzerland and spent a few days there before we set off to hitchhike to Greece. We spent most of the next four months together and I acquired an acute sensitivity to religious swearing (and, for all I remember, to all swearing). According to Hume, such sensitivity is invariably grounded in ego, and is inseparable from feelings of outrage and offence. None of these things applied in my case. The feeling I developed when hearing such swearing was simply one of shock and intense dismay. I got over it, but I know what it’s like. I don’t think Hume does.

It’s essential to his case that the line between harm from words and harm from physical blows is perfectly sharp. But it isn’t. Privately, at least, some find verbal abuse harder to take than physical cruelty. Hume seems to endorse an old false dualism of mind and body that supposes the mind to be always less vulnerable than the body. On this basis he slams the “liberal elite” for insulting and infantilising “the people”, treating us as weak, pathetically impressionable, “one big susceptible infantile blob”, desperately in need of protection from hurtful words. The problem is that Hume enjoys his assault on the “ethical elite” too much to acknowledge the power of words – even though their power is crucial to his case for free speech. It’s worth adding that we’re all “the people”, and we really are hopelessly weak, impressionable and comically self-ignorant. We’re often deeply mistaken about why we’re doing what we’re doing (see Strangers to Ourselves by Timothy Wilson or Thinking, Fast and Slow, by Daniel Kahneman). This isn’t a snooty judgment passed by the elite on the masses; Hume’s model of the robustly autonomous citizen is in profound ways a fiction. It is, perhaps, a fiction we need to maintain, but that’s another matter.

It doesn’t help that Hume himself belongs to a certain elite – of professional writers and talkers, toughened journalists, politicians and polemicists who know how to give it and take it. (He has been editor of the Revolutionary Communist Party’s paper, and of Living Marxism and the web-only Spiked.) He has a tough mental shell, by nature and training, and it puts him in a position of high privilege in this debate. He can sing “Sticks and stones may break my bones / But words can never harm me” with a full throat, and lambast people such as Stephen Fry who adjust the second line to “words will always harm me” (or even, “only words can harm me”).

Another consequence of his carapace is that he doesn’t offer much advice about how to put up with verbal thuggery, except to say that one can always fight back with words. He isn’t deterred by the ancient adage “he that wrastleth with a turd shall be beshitt, fall he over or under”. Others are. I find it useful to remember that insults are boomerangs; they whip back unerringly into the face of the insulter. This isn’t merely an uplifting fiction, it’s true without exception, whatever else may be going on. It’s worth training oneself into hearing it. It can speed one past the flash of fury or thud of dismay.

Hume also says very little about images and pornography. This is perhaps the most serious omission in the book. The easy availability of pornography is a tragedy – not just because it makes it far harder for someone to acquire a capacity for sexual love and hence for the best sex. There’s a close parallel between what chronic indulgence in pornography does to the mind and what chronic overeating of bad food does to the body, although sexual mental obesity isn’t immediately visible in the way that bodily obesity is.

Hume thinks that the fundamental cause of outrage and offence is narcissism. In fact it’s something vastly more toxic: righteous indignation felt on behalf of others – typically a group with which one identifies or sympathises. Righteous indignation can stem from concern for the powerless; it can be a good thing. More often than not, however, it’s something uniquely ugly, very human, very dangerous, arguably the most noxious force in public affairs. It’s precisely because such righteous indignation is not narcissistic, and is not experienced as mere self-concern, that it comes with a feeling of absolute purity – purity of cause and of justification – that seems to license absolute violence. As often as not, it’s driven by people’s unconscious anger with themselves or their lives, and this gives it frightening power. Hitched to a seemingly unselfish cause, the anger is cleared to express itself without inhibition.

I strongly recommend this book. Hume is right that the current proliferation of trigger warnings is absurd, even if he is too dismissive of our sensitivities. But he is, finally, wrong to think that he is “always with that great Englishman of letters Dr Samuel Johnson”. When he quotes Johnson’s remark that “every man has the right to utter what he thinks truth – and every other man has a right to knock him down for it”, he has to interpret “knock down” as a matter of words only. He doesn’t mention Johnson’s view (recorded in the same paragraph of Boswell’s Life of Johnson) that “the state has a right to regulate the religion of the people”. Nor does he cite Johnson’s response, when discussing religion, to the claim “that no man could be hurt by another man’s differing from him in opinion”: “Sir, you are to a certain degree hurt by knowing that even one man does not believe.”

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