In a conversation with David Gelernter, the groundbreaking computer scientist, artist, and polymath, David Mikics learns what’s Jewish about Gothic cathedrals:

Gelernter and I agreed that Jewishness is in political peril these days, at least in Europe. Jeremy Corbyn is a “bigot,” he told me, “the most revolting kind of human being.” According to Gelernter, “anti-Semitism comes naturally to Europeans,” but thankfully not to Americans. That wasn’t always the case: the great medieval cathedrals were infused with Hebraic inspiration; Jewishness was, he said, the “hand inside the puppet” of Christian Europe.

“My parents took me to Sainte-Chapelle when I was five years old, and it knocked my socks off,” Gelernter told me. “I’ve never had a day since when I haven’t thought about medieval art.” The art of the cathedrals, Gelernter argued, is Hebraic, with a vast empty space at the center that resembles the emptiness in the Temple’s Holy of Holies, the most fitting image of a transcendent God. And there’s the medieval idea of gallantry, which combines military bravery with piety in a way reminiscent of the Hebrew Bible. Judah Maccabee, Gelernter reminded me, was a central example of chivalry for the Middle Ages.

Gelernter loves the Basilica of Saint-Denis, “where Gothic art was invented in 1144.” “One late afternoon the gisants [tomb effigies] were eloquent, articulate; that’s how I decided to do the Jewish paintings I modeled after them.” He said, “I didn’t set out to be a Jewish painter like Marc Chagall, but one like Amedeo Modigliani or Chaim Soutine.” But, he added, Jewish themes are a bad idea for a painter, commercially speaking. “The Israeli art market is aggressively secular; there’s more interest in my paintings in Germany.”

Two extraordinary events demonstrate something important about Israel’s most fervent adversaries. One was a speech given at something called The People’s Forum (funded generously by Goldman Sachs), which stated, “When the state of Israel is finally destroyed and erased from history, that will be the single most important blow we can give to destroying capitalism and imperialism.”

The suggestion that this tiny state is the linchpin of a global, centuries-old phenomenon like capitalism goes well beyond anything resembling rational criticism. Even if Israel were guilty of genocide, apartheid, and oppression—which of course it is not—it would not follow that its destruction would help end capitalism or imperialism.

The other was an anti-Israel protest that took place in front of New York City’s Memorial Sloan Kettering Cancer Center, deemed “complicit” in Israel’s evils. At organizers’ urging, participants shouted their slogans at kids in the cancer ward, who were watching from the windows. Given Hamas’s indifference toward the lives of Gazan children, such callousness toward non-Palestinian children from Hamas’s Western allies shouldn’t be surprising. The protest—like the abovementioned speech—deliberately conveyed the message that Israel is the ultimate evil and its destruction the ultimate good, cancer patients be damned.

The fact that Israel’s adversaries are almost comically perverse does not mean that they can be dismissed. If its allies fail to understand the obsessive and irrational hatred that it faces, they cannot effectively help it defend itself.