Matrilineal Descent in Judaism

Matrilineal Descent in Judaism enters the novel through a personal dispute over whether Diotallevi can claim Jewish identity when his grandmother was not Jewish. The rule becomes a point of friction between formal descent and lived identification; later, the novel’s fabricated account of anti-Semitic conspiracy reveals the destructive consequences of turning Jewishness into a device for explaining political events.

A Personal Dispute About Descent

Casaubon raises the rule directly: Diotallevi’s grandmother was not Jewish, he observes, while Jewish descent is understood to pass through the mother. The question is not treated as an abstract legal discussion. It touches Diotallevi’s own identity, which he defends in terms of both ancestry and intellectual affinity.

Diotallevi answers that, beyond registry records and municipal ledgers, he feels Jewish through his blood and through what he describes as the Talmudic character of his thought. He rejects the implication that a gentile could possess that same quality, making his claim both a declaration of belonging and an argument against having his identity judged solely by records. The exchange leaves the disagreement unresolved rather than supplying a definitive account of his maternal ancestry.

Belbo’s Response

After Diotallevi leaves, Belbo tells Casaubon that the two have this argument almost every day. He identifies Diotallevi as a devotee of the Kabbalah, while noting that Christian Kabbalists have also existed. Belbo’s practical response is that Diotallevi should be allowed to identify as Jewish if that is what he wants; Casaubon agrees. Their conversation shifts the focus from adjudicating Diotallevi’s status to recognizing his stated attachment, without erasing the distinction between religious practice, descent, and self-understanding.

Identity Turned Into Conspiracy

Elsewhere, the novel shows how claims about Jewish identity are weaponized in conspiracy narratives. Diotallevi proposes, within the trio’s invented historical scheme, that the Protocols of the Elders of Zion emerged from anti-Semitic political manipulation in Russia. The book presents the Protocols as a program falsely attributed to Jewish elders and describes its contradictory claims about power, liberalism, revolution, and anti-Semitism. This is not evidence about Jewish belief or action; it is evidence of how a forged text can make an invented collective identity appear to explain political disorder.

The account traces another stage in this process to the Jesuits’ decision to attribute a document to the Jews, using Simonini’s letter as a pretext. It then recounts how a pamphlet associated with Elie de Cyon was altered in the trio’s reconstruction: Rachkovsky substituted Jews for Witte as the supposed target of the text’s accusations, and the document was circulated in a form that appeared to expose a Jewish plot. The narrative’s chain of attribution shows how forgery and selective editing can convert political conflict into anti-Semitic accusation.

The Cost of the Fabricated Reading

The trio’s conspiracy story ultimately reaches a horrific reinterpretation of the Holocaust. In their delusion, they claim that the Nazi genocide was a search for a hidden clue linked to the Thirty-six Invisibles and the supposed location of telluric currents. The novel presents this as the Plan’s explanatory fantasy, not as a factual account of the Holocaust. By forcing a secret pattern onto the persecution and murder of Jews, the conspirators turn real suffering into supposed evidence for their own construction.

Against that machinery of imposed meanings, Diotallevi’s earlier argument retains its human scale: he insists on a belonging that Casaubon questions and Belbo accepts without claiming authority to settle it. The contrast is central to the subject’s significance. A rule of descent appears first as a difficult question of personal identity; in the trio’s invented history, Jewishness is then stripped of individual lives and made into a false explanation for political events and mass violence.