Jacopo Casaubon

Jacopo Casaubon is the narrator of the novel’s final reckoning with the Plan: a scholar who helps invent a universal conspiracy as a joke, then discovers that repeated acts of imaginative connection can erode the boundary between pretense and belief. His account traces that transformation from ironic intellectual play to personal danger, while his bond with Lia offers a counterweight grounded in ordinary life.

The Plan as an Intellectual Game

Casaubon had kept the Plan from Lia, who knew only vaguely that he, Jacopo Belbo, and Diotallevi were working on a puzzle that consumed their days and nights. When he finally tells her the whole construction, including the smallest details and Diotallevi’s illness, he tries to present it as bravura rather than conviction. The confession also carries guilt: he feels as if he has done something wrong, and Lia’s immediate dislike of the story makes clear that the Plan does not remain safely contained within the circle that made it.

The Plan’s governing joke is that a secret society plots to spread the rumor that a universal plot exists. Casaubon states the proposition plainly, but the joke acquires force because conspiracy thinking can convert frustration into an explanation that blames hidden enemies rather than confronting failure or uncertainty. The Plan’s collaborators push the logic toward absurdity: if even one fact in the universe fails to disclose a mystery, they have violated Hermetic thought; Minnie Mouse, too, can be made part of the system, and the Templars can be declared connected to everything.

How Pretending Becomes Belief

At first, Casaubon and his companions recognize that their links are unwarranted associations and extraordinary shortcuts. They tell themselves they are parodying the reasoning of their imagined adversaries. But the long intervals spent collecting material for their meetings train their minds to connect one thing to another automatically. Casaubon sees the danger in the habit itself: pretending to believe and learning to believe can cease to be distinguishable.

He describes the three men as changing in different ways. His daily contact with Lia and their baby seems to leave him the least affected; he imagines himself still controlling the emotional game, as he had stood aside from the emotions during the rite in Brazil. In retrospect, however, he judges that he was becoming addicted to the process, while Diotallevi was being corrupted and Belbo converted. All three were losing the capacity to distinguish resemblance from identity and metaphor from reality. The Plan’s danger is therefore not simply that someone might mistake a false claim for a true one, but that repeated interpretation reshapes the interpreter.

That self-diagnosis sharpens when Casaubon explains the Plan to Lia. Her earlier warning about the psychosis of resemblances had stayed with him, and his shame helps explain why he had withheld the story. He presents the construction as a display, but he cannot simply abandon it: after living with it so long, he still feels its pull. The game has become an attachment as well as an intellectual method.

Lia and the Ground of Ordinary Life

Lia’s response challenges the Plan from outside its closed system. She had been occupied with the baby and had not been told what Casaubon and his colleagues were doing; when she hears the full account, she rejects it. Their disagreement does not ruin their weeks in the mountains, where Casaubon takes long walks, reads serious books, and grows closer to the child. Yet something remains unsaid between them. Lia is sorry that she has put him in a tight corner and fears she may have humiliated him, but she is not convinced that she has changed his mind.

Casaubon later recognizes that they should have talked earlier, though he doubts that he would have believed her then. He had experienced the Plan’s creation through the image of Tiferet, the heart of the sefirotic body, as a harmony of Rule and Freedom. Only later does he begin to understand Malkhut as the kingdom of the earth in its dazzling simplicity. The contrast marks a change in what he can see: an elaborate symbolic system had seemed to offer a higher order, while Lia, the child, and the material world expose what that system leaves out.

From Confession to Action

After reading Belbo’s confessions in Belbo’s apartment, Casaubon faces a decision. It is six on a Saturday morning, June 23; there is no point going to Signor Garamond, De Angelis has left, Diotallevi has said what he had to say, and Lia is far away in a place without a telephone. Casaubon believes that if anything is to happen, it will happen that night at the Conservatoire, so he must act quickly.

Later, while concealed in the museum, he questions why he did not dismiss Belbo’s writings as the product of a madman speaking with other madmen. He cannot be sure Belbo even called from Paris; the call may have come from somewhere near Milan or from a street telephone booth. At the time, however, Casaubon feels curiosity and perhaps duty and friendship, not fear. That hesitation between skepticism and involvement defines his position: he can name the reasons to doubt the story, yet still chooses to enter its danger.

The Empty Secret and the Ending

Casaubon ultimately understands the Plan’s power through the secret Belbo claimed to possess. The more Belbo refused to reveal it, and the more he denied possessing it, the more the conspirators believed it must be real and immense. Their pursuit had held them together through excommunications, internal conflicts, and coups; now they feared both that the secret would disappoint them and that knowing it would destroy the very secrecy on which their identity depended. Casaubon recognizes that the secret’s force lies not in hidden information but in its continual deferral.

The same mechanism explains how an invented Plan can become effective. Its believers identify fragments of their own confused mythologies as moments in Casaubon and his companions’ web of analogy, resemblance, and suspicion. Once they act on that construction, it exists in consequence even though it was fabricated. Casaubon’s final account thus turns from a record of how the Plan was assembled into an examination of how belief manufactures the reality it claims merely to discover.

The narration begins at a point when Casaubon is already drawn back into the crisis: after leaving for Milan by the one early train, he receives Belbo’s call from Paris and begins telling the story, which he says is not yet finished. His last thought turns toward Lia. He does not know whether he will see her again; he remembers her half-asleep under the blankets, recalls kissing her that morning, and remembers hesitating before he left. The hesitation gives the ending its human measure: beside the Plan’s limitless chain of meanings stands a particular person and a parting that may have been final.