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Foucault’s pendulum – Umberto Eco

Foucault’s Pendulum is a novel by the Italian writer and philosopher Umberto Eco. It was first published in 1988, and an English translation by William Weaver appeared a year later.

It is divided into ten segments represented by the ten Sefiroth. The satirical novel is full of esoteric references to Kabbalah, alchemy, and conspiracy theory. The title’s pendulum refers to a real pendulum designed by the French physicist Léon Foucault to demonstrate the rotation of the Earth, which has symbolic meaning within the novel.


Summary and Synopsis

Foucault’s Pendulum is a novel that follows the adventures of three book publishers in Milan as they try to unravel the great mystery of the Knights Templar. Eventually they are sucked into a hidden underground world filled with secrets and magic where the Plan they have developed becomes more powerful than they could have imagined.

The novel begins with the main character and narrator, Casaubon, hiding at the Conservatory of Arts and Metiers in Paris to try to find his kidnapped friend Belbo. Years ago, when Casaubon is still a graduate student in Milan, Belbo and Casaubon speak to Colonel Ardenti, a former Fascist and Templar fanatic, who claims to have a secret Templar message.

Casaubon, at that time, is working on a dissertation on the Templars, so Belbo consults him on the Ardenti document. Initially, taking the colonel like crazy, the two men are intrigued once they learn that Ardenti, apparently, was killed.

Years pass and Casaubon, now with his degree and teaching in Brazil, meets a mysterious man named Aglie who claims to be the immortal Earl of Saint-Germain. Casaubon befriends Aglie and reintroduces himself to the mysterious knight once he moves to Milan.

Back in Milan, he meets Belbo again, who tells him about strange coincidences related to the Templar message of Ardenti. Intrigued, Casaubon and Belbo begin to look at the Templars and the occult once again. He is then hired to work with Belbo in the Garamond press as an investigator.

Belbo and Casaubon devise an ingenious way to spend their free time in Garamond, which consists of feeding fragments of manuscripts sent to the press on subjects hidden in Belbo’s computer, Abulafia, and trying to interpret the results.

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This game leads to the creation of the Plan, what Belbo and Casaubon call their explanation of the text that comes out of Abulafia. The Plan eventually becomes a complete hidden story from the world claiming that the Templars, in their most modern forms, are conspiring to dominate the world by harnessing the power of underground telluric currents.

Meanwhile, Aglie has been hired as a consultant to the Garamond Press for a series of books they are doing on the occult.

Belbo is absorbed in the Plan, dedicating all his time to it. In an attack of jealousy because he believes that Aglie is a romantic rival, Belbo tells Aglie the whole plan and claims to have the secret map of the Templars that will allow its owner to gain control of the telluric currents.

Aglie, apparently the leader of a secret society of her own, frames Belbo as a terrorist and forces him to travel to Paris, where he kidnaps him. Casaubon witnesses Belbo’s murder in the museum where he is hung from the Pendulum because he refuses to give up the location of the nonexistent map. Casaubon escapes from the museum and returns to Italy. He goes to Belbo’s childhood home, where he believes that Aglie’s secret society will kill him.

Genre: novel

It is considered within the subgenres of the “Secret History” since history takes a new reinterpretation of the events that are narrated, relating events that could have been suppressed by historians for convenience. It is also considered as an allegory to past events, combined with adventure.

Told by an omniscient narrator, it has a somewhat tragic, violent tone and we can even say that it is impressive.


  • Casaubon: As the protagonist, Casaubon dictates the rhythm of the plot. He is a young man fascinated, almost to the point of obsession, with the hidden and the mystery. At university he writes about the Templars. Although he spends a few years searching for romance and family, he is dragged back into his graduate world through work.
  • Amparo: She is a lover of nature, fed by revolutionary Marxism. Her various opinions are why Casaubon loves her. After having a bad trip during a magical ritual one day, Amparo is lost.
  • “Garamon” Belbo: ​​Belbo is the editor of a local publishing house in Milan. Meeting Casaubon while still in college, Belbo has a taste for the young man’s curiosity and intellect, inviting him to work for him later when he owns his own newspaper.
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  • Leah: She is Casaubon’s second girlfriend. She gives birth to her baby just as Allier becomes a victim, thus representing a responsibility to Casaubon. He sends her and the baby to the mountains, even after the events are over.
  • The Colonel: This man is a retired colonel who appears at the newspaper door one day with information about the Templars. He reveals the secret plan orders to Casaubon and his friends.
  • Diotavelli: works with Belbo when Casaubon meets him. It represents the third member of his trio, with the intention of discovering the Templar secret. Of the three, he is the least dramatic and offensive, and often positions himself as a peacemaker.
  • Mr. Allier: Originally from Brazil, Belbo hires you as a consultant for his newspaper. He quickly convinces Casaubon to confide in him about the Templar conspiracy due to his extensive knowledge of the occult, although Casaubon has his reservations. Allier turns out to be a villain, intending to exploit the Order of the Temple Knights for his own benefit.


Foucault’s Pendulum is, like The Name of the Rose (1981), an intellectual thriller loaded with an incredible variety of references, ranging from African mythology to medieval history. And like its fictional predecessor, Foucault’s Pendulum examines the nature and necessity of faith.

The novel narrates two decades in which the narrator Casaubon investigates secret societies that begin with the medieval Knights Templar and the possible existence of “a Plan, a universal plot” to control the enormous powers of the earth.

What begins as an independent academic study at the University of Milan in the late 1960s becomes an obsession that some twenty years later not only dominates Casaubon’s life but threatens his own existence and claims the lives of two of your friends and colleagues. As a metaphor for the high price to pay for knowledge.