Three made up a "plan"

The invention of the Plan is the collaborative act by which Casaubon, Jacopo Belbo, and Diotallevi turn the esoteric manuscripts and theories arriving at their publishing firms into a supposed, centuries-spanning Templar conspiracy. Its decisive consequence is not that the three discover a hidden design, but that they make one: by connecting material through analogy, they produce a fiction convincing enough that its supposed adherents recognize themselves in it and begin to pursue it as fact.

From parody to a cosmic design

The game begins with an intentionally extravagant premise. Casaubon’s formulation is that a secret society exists throughout the world to spread the rumor that a universal plot exists. The joke captures the self-confirming logic of conspiracy: ordinary failures and political disorder are assigned to hidden enemies, while the imagined plot itself supplies an explanation. The men are not merely inventing a secret society; they are imagining an organization whose purpose is to make people believe in secret organizations.

Their method becomes explicit when Diotallevi argues that they must overdo the connections. If even one fact in the universe is allowed to reveal no mystery, hermetic thought is violated. Belbo adds the axiom that the Templars have something to do with everything. The principles have no limiting test: each new association can be admitted, while any apparently unrelated fact becomes a challenge to be explained away. The Plan grows not by uncovering independent evidence of one historical design, but by treating the demand for universal connection as its own warrant.

That process becomes a deliberate performance. The three know that their associations are unwarranted and tell themselves they are parodying the logic of the Diabolicals whose manuscripts they handle. Yet their brains adapt to the work of connecting everything. Casaubon later distinguishes their different degrees of involvement: he thinks himself still in control, partly because of his daily life with Lia and the baby; Diotallevi is becoming corrupted from within; Belbo is becoming converted more consciously. The distinction between pretending to believe and believing gradually loses its force. The Plan’s invention thus contains the danger of its own reception: sustained imitation trains its authors in the very habits of thought they mean to satirize.

Giving the Templars a secret

The turning point comes when the men decide that their invented history needs an adequate secret. Casaubon reads his notes to Belbo and Diotallevi, and the accumulated pieces at last seem to form an elegant, economical solution. In the mythology they construct, the Celts learned knowledge of telluric currents from survivors of Atlantis, who had emigrated to Egypt and Brittany. That inheritance is extended further back to ancestors who journeyed from Avalon across the continent of Mu to Australia in the age when the continents formed Pangaea. The account connects legendary migrations, lost civilizations, occult geography, and the claim that megaliths were instruments for mapping the Earth’s hidden forces.

The three elaborate the system through specific features of prehistoric monuments. Menhirs become sensitive devices placed where currents branch; leys mark the routes of currents; dolmens serve as chambers in which energy accumulates; and cromlechs and Stonehenge become observatories linking the pattern of the stars to the pattern below. Casaubon’s account treats the “as above, so below” principle as the key that makes the constructions appear to confirm a universal scheme. Their materials are not simply collected but reorganized: every landmark is assigned a function within the secret history they are making.

The invented doctrine then acquires a command center. The Earth, imagined as a great magnet whose currents shift with celestial movements, seasons, and cosmic cycles, must have a critical point from which the whole system can be controlled. The Templars’ real secret, in the Plan’s fiction, is therefore not merely a global map but the location of the Omphalos, the Umbilicus Telluris, the Navel of the World—the source of command. Alchemical stages are recast as metaphors for progressively deeper knowledge, culminating in dominion over the planetary system of currents. Even the medieval accusation involving a mysterious kiss is reinterpreted as a distorted trace of the supposed Kundalini secret. A question from Diotallevi—what would anyone do with currents once they could direct them?—registers the gap between the grandeur of the system and its practical purpose, but does not halt its construction.

The map, the Pendulum, and the method of connection

The invented history also supplies a reason for delay. In one part of the Plan, the Templars have exploited their knowledge to locate silver deposits in the New World, provoke eruptions of silver, and direct the precious metal toward the Portuguese coast, with Tomar as a distribution center and the Forêt d’Orient as a storehouse. But this wealth is treated as a preliminary use. The Templars supposedly arrange for their successors to learn the location of the Earth’s command point only when a technological age makes the knowledge fully useful, hundreds of years later.

A practical puzzle follows within the fiction: how could a revelation be divided among thirty-six people around the world? A conventional map marked with an X would make the fragment containing the mark decisive and render the others unnecessary. The men therefore need a system in which the separate fragments matter together. Belbo turns to Abulafia, whose terse output places Guillaume Postel’s death, Bacon’s title, and the Pendulum at the Conservatoire alongside one another. The fragment does not prove a historical relationship among them; it furnishes fresh material for the Plan’s associative machinery.

Casaubon supplies a function for the Pendulum by drawing on a manuscript about the hermetic secret of cathedrals. In the story they construct, builders at Chartres used a plumb line hanging from a vault’s keystone to deduce the Earth’s rotation. The labyrinth beneath the Pendulum is then reinterpreted as an image of the subterranean-current system: at once a solar clock, compass, vein network, and route of the Serpent. The object that had seemed to need an explanation becomes the apparent instrument and emblem of the very system the men are inventing. The Plan’s pieces do not independently converge on a verified answer; the men assign each new piece a role that makes the growing design seem to converge.

The work takes place through a sustained, feverish search. The trio consult encyclopedias, newspapers, comic strips, and publishers’ catalogs; stop at bookstalls and newsstands; and bring manuscripts and discoveries back to the office. Casaubon remembers the research as a rapid succession of errands and finds, while the Plan itself appears to form slowly and methodically between these bursts. The contrast matters: the labor feels disciplined even though its governing procedure is to seek connections wherever they can be found. In that search, the world becomes a network in which everything points to and explains everything else.

A fiction that recruits its believers

The Plan’s most consequential success occurs outside its authors’ intentions. Casaubon later explains that the men invented a nonexistent Plan, but the Diabolicals believed it real and persuaded themselves that they had belonged to it for ages. They reinterpret fragments of their own muddled mythologies as episodes in the men’s design, joining them into what seems to be an irrefutable web of analogy, resemblance, and suspicion. The fiction does not need to have existed in the past to acquire force in the present: once others believe in it and act upon it, it exists as a social fact.

That transformation explains the danger in the trio’s original parody. As they gather material, they acquire the reflex of connecting everything with everything else; the practice that begins as an imitation of the Diabolicals becomes a habit, and the habit threatens to become belief. Casaubon’s claim that he is least affected does not mean he is untouched. His later account recognizes that all three are losing the ability to distinguish a metaphorical resemblance from an identity, or a figurative description from literal fact. The invention is therefore also a change in its inventors: the Plan is not only a structure they build, but a way of seeing that begins to govern them.

The novel links this way of seeing to the emotional usefulness of conspiracy. When people cannot make sense of failure, they can imagine a plot and assign blame; when they feel guilty, they can invent enemy designs and organize their own in response. Each side then treats the other’s hostility as proof that the reciprocal plot was real. Against that cycle, the men’s original conceit—a secret society that manufactures belief in a universal plot—becomes less an isolated joke than a model of how suspicious explanations can reproduce themselves. Their Plan offers the apparent order of a single design, but the order comes from the interpretive appetite that keeps supplying connections.

The secret without content

The final irony is that the Plan’s supposed secret cannot satisfy the desire that sustains it. A secret is imagined as the knowledge that would dispel frustration or bring salvation; but if it is revealed, it proves smaller than the longing invested in it. The search therefore requires not a greater answer but an endlessly receding one. Casaubon figures initiation as an infinite series of meanings: one sign points to another, and each apparent center opens onto further interpretation. The secret that cannot be reached is powerful precisely because it remains available for pursuit.

This logic illuminates the later ritual at the Pendulum. Belbo claims to possess a secret, and that claim gives him power over those who have gathered. Aglie summons the others and tries to extract it; Belbo’s refusal makes them more certain that the secret must be immense, while his denial that he possesses it is taken as further evidence that he does. The Plan has trained its believers to convert the absence of confirmation into confirmation. Their long search has bound them together, yet they fear both that the answer will disappoint and that knowing it will end the secret—and with it the identity and power built around seeking it.

For Aglie, the stakes are personal as well as doctrinal. If Belbo disclosed the secret to everyone, the mystery surrounding Aglie’s claimed identity as the Comte de Saint-Germain would diminish; if he told Aglie alone, Aglie could preserve his charisma. Casaubon recognizes that the postponement of Aglie’s supposed death coincides with the postponement of the secret. Belbo refuses to whisper it, and Aglie presses him by predicting that he will yield and staging his melodrama. In retrospect, the danger at the Pendulum appears as the consequence of the Plan’s central mechanism: an invented secret has become compelling enough that its believers will risk violence to possess what may have no content beyond the search itself.