What on Earth could an economist, industrialist, composer, political leader and a Nobel Prize-winning physicist share when it comes to a consuming obsession that has nothing to do with their chosen fields, one so great that it leads them to write long, passionate treatises on it?

The disparate persons of Karl Marx, Henry Ford, Richard Wagner, Adolf Hitler, and Johannes Stark all had one thing in common: the Pattern.

Likewise, in our times, what could possibly unite and dominate the waking hours of a millennial Irish novelist focussed on tales of sex among rich Dubliners (Sally Rooney), a young Swedish environmentalist (Greta Thunberg), an ancient Jewish professor of linguistics (Noam Chomsky), a pair of young Israeli film-makers (those behind Naza), a white American rapper (Macklemore), a Nobel Peace Prize winner (Navi Pillay), the journalist-wife of a senior government official (Sarah Helm), and Gaza’s rulers (Hamas)? One thing and one thing only: the Pattern.

The Pattern is a theory of anti-Semitism proposed by the physicist David Deutsch, recently published as a 14-page essay via X. It is: “a contagious, irrational pattern of thinking about morality that has persisted for millennia, characterised by a compulsive need to legitimise hurting Jews, for being Jews.”As someone who writes and thinks a lot about anti-Semitism and its offshoots, I have increasingly felt we are getting the definition, and therefore, our understanding of how anti-Semitism actually works, wrong. That perhaps we have always got it wrong.

Last weekend I attended a panel at the Battle of Ideas entitled: “Is Anti-Zionism really Anti-Semitism?”Each speaker was great and some were veterans in this area, but it didn’t quite work because the whole room’s understanding of what anti-Semitism is was off. It was, indeed always is, like trying to explain an exotic orange only with reference to bananas and apples. But we don’t have time to waste on that. We need a new, truer understanding, and Deutsch provides it. What is the Pattern?

Don’t get thrown by that ugly Latinate word “legitimisation”. It means “acting to protect [the hurting of Jews] from being deemed morally wrong, dishonourable, taboo or intolerable”. The word is crucial, because it allows us to see why anti-Semitism behaves the way it does, with the results it has, often without a single Jewish hair being touched.

Because here’s the thing. You can make something out to be fair play (legitimise it), without doing it yourself. Emigration or gay marriage, for instance.

Legitimising the hurting of Jews, without insulting or abusing them directly, is how a lot of anti-Semitism works these days in the West. Relatively little of it involves physical violence against Jews or hurling insults at them about their big noses and stinginess.

Most of it involves making contorted and bizarre arguments, in polite or virtuous language, in order to defend, at any cost, regimes or groups or actions whose main purpose is to hurt, you guessed it, Jews.

For instance, you can make it sound like a deal with Iran is a realistic option, when really everyone knows all the regime wants is nukes at any cost, and that the first target of such weapons is Israel.

Or, you can be a Jewish community leader while also giving credence to a form of the blood libel, an ancient conviction that Jews violate their own taboo against drinking blood in order to ritualistically murder non-Jewish children and... drink their blood.

The most common version now is that Israel is committing a genocide, and that the war on Hamas is driven by Israeli zeal for killing Palestinian children. This version of the libel is espoused by almost all anti-Israel people, including some Jews. Such a position regularly leads people to excuse and lessen actions of Hamas on October 7 and of Palestinian terror in general.

You can argue for the deal with Iran, and essentially excuse Hamas, while being polite, and even kind, to individual Jews, as many die-hard Israel-haters, from Jeremy Corbyn to Gary Lineker, no doubt are. Many such people literally do not hate actual Jews they know. But they’re still enacting the Pattern.

Anti-Semitism is fascinating and urgent not because of the threat of actual physical harm (which remains pretty low), but because of the social and political behaviours that it causes. These are among the most grippingly strange and troubling features of the contemporary political scene worldwide.

But grasping what anti-Semitism essentially “is” remains an endlessly circular and unsatisfactory project, even among Jews, even among the cleverest Jews in the world, and that is because we’ve been thinking about it all wrong. Here’s why.

The anti-Semitic urge is a pre-disposition Anti-Semitism is not in fact principally a hatred, as coherent as an ideology (or something that emanates logically from an ideology), nor as rational as a grab for power – as the brilliant US author Dara Horn argues it is in her most recent book, The Final Solution To the Jewish Question.

When hating or detesting Jews is widespread too, the Pattern posits, this is “a consequence, not a cause, of the need to legitimise hurting Jews.”The kernel, which I think of as a virus, is already there. The rationalisations of that kernel (hatred, need for power, insecurity, bigotry etc) and whatever it may force one to do or feel (rant against Jews, incite hatred against them, espouse conspiracy theories) follow.

Wagner had an inkling of what was at work in him and his brethren. In Das Judenthum in der Musik (1850) he described “that unconscious feeling, which manifests itself as the People’s inherent disgust at Jewish existence”. Whether it’s “an unconscious feeling” or not, Wagner was right that the impulse precedes the manifestation.

In his 1946 book, Anti-Semite and Jew, Sartre highlighted the absurdity of how people explain their anti-Semitic predisposition. “A young woman said to me: ‘I have had the most horrible trouble at a furrier’s; they robbed me, they burned the fur I entrusted to them. Well, they were all Jews.’”But why Jews rather than furriers? Why Jews or furriers rather than that particular Jew or furrier? The answer, of course, is that it had to be “the Jews”, because the young woman carried a predisposition toward anti-Semitism.

A similar absurdity is present in the Saudi Arabia of Ayaan Hirsi Ali’s youth. As she recounts in her memoir Infidel: “In Saudi Arabia, everything bad was the fault of the Jews. When the air conditioner broke or suddenly the water stopped running, the Saudi women next door used to say the Jews did it.”That there were no Jews there made no difference. Where are the anti-clown movements?

The particularity of anti-Semitism, its weirdness and exceptionalness, is not only in the fact that people are predisposed to distrust or blame Jews. This is another mistake we often make.

Predispositions to dislike certain types of people are not unusual. As Deutsch notes, some people dislike clowns. “Yet there is no enduring phenomenon of false accusations against clowns; clown-hatred is not woven into the fabric of political philosophies, national identities and religions; there were no clown-phobics two centuries ago, let alone two millennia,” he writes.

The difference with clowns (or gypsies, another vilified group), is the “enduring perversions of thought that exist only in regard to Jews” and the way these perversions make people with “otherwise disparate ideas conform to the same Pattern”. Why it works like this, only in relation to Jews, is not yet explained.

But for some reason, it always does work like that: anti-Semitism is that strong a pattern. It is capable of uniting and mobilising unbelievably widespread and disparate blocs with world-shattering results.

In 2006, Mel Gibson ranted to an arresting officer that the Jews were responsible for all the wars in the world. The fact that billions agree with him on this bizarre libel – and nothing else – illustrates the point. It is unthinkable that he would have ranted, and been agreed with so widely, on any other topic.

Spot the contortions Only the Pattern accurately describes the uniquely bizarre moral contortions, contradictions and flagrantly illogical arguments required for ensuring that pathways to harming Jews remain open, especially when doing so butts up against other kinds of moral thinking. A good example is where the self-described pacifists cannot bring themselves to oppose the October 7 violence against Jews, and instead often celebrate it.

Think about the record of this year’s Nobel Peace Prize winner, Navi Pillay. Genuine genocides, from the Uighurs to Sudan; offensive, imperialist and murderous wars such as that waged by Putin on Ukraine; and bloody repressions, such as that in Iran, all get the nod of silence from her.

She was even accused by one whistleblower of being complicit in China’s persecution of the Uighurs (a claim she has denied). But in the eyes of the Nobel committee, the UN, Pillay and millions of others, the only obstacle to “peace” the world over is the Jews of Israel, and any measure against them must therefore be merited. This is the true commitment to “peace”.

Or consider Sir David Bell’s independent report for the Government, released last week, revealing widespread and explicit anti-Semitism in schools. The persecution of Jewish children was immediately condemned as a “stitch-up” by some of the most passionate defenders of the weak. The Guardian columnist Owen Jones instantly promised to “debunk” the report and claimed it was based on “BS numbers”. It is a shockingly indecent, as well as irrational response.

It only makes sense in light of the Pattern. It means making no sense at all, but people infected badly with it will keep doing it, no matter the cost. As my colleague Nicole Lampert pointed out this week in an increasingly heated recent exchange on X with Sarah Helm: “I don’t understand why anyone who hates war would repost what appeared to be a celebration at the start of another war on Oct 7, 2023.”Quite. It’s the unique moral pathology of the Pattern.

And so, it is only through recognising that the Pattern is a moral sickness, not a localised “bigotry”, that we can begin to see its magnitude and power. As Deutsch also says, where there is sufficient evil, you will likely see the Pattern. “No demographic is exempt from it,” writes Deutsch, “and its cost is stupendous.”Without correctly diagnosing it, we have no hope of solving it.