The scientists (though they'll be called something else) in a world all belong to an organization that functions pretty much like a religious order, with features like a distinctive dress code, years of strictly regimented study, cloisters segregated from regular society, and vows of chastity. But, they're devoted to science for the sake of science, and are usually pretty disdainful of religion and the supernatural. Sometimes works as a parody of modern academic life. Very Loosely Based on a True Story, since in the Middle Ages "scholar" and "monk" were practically synonymous. But medieval monks were, at least in theory, concerned with God first and Science second.
- Anathem depicts a world in which all scientific inquiry is carried out by cloistered savants who may only interact with the outside world every one, ten, hundred or thousand years. They're also forbidden from making any invention beyond a certain level of sophistication
- The Maesters of A Song of Ice and Fire fit this trope perfectly, and even manage to exist alongside, and often opposed to, the more conventional religious order of "septons."
- The Sword Of The Spirits trilogy by John Christopher (Samuel Youd). The Seers are a monastic priestly class that interprets the will of the "Spirits". However, they are actually scientists who want to bring back the use of technology.
- Discworld wizards are pretty close to this. Unseen University is inspired by Oxbridge and there are some parallels with the British scientists of the Scientific Revolution, along with some students who are outright parallels to modern geeks. Wizards have an semi-official celibacy rule in play because the seventh son of a seventh son of a wizard will be a Physical God/Person of Mass Destruction, although they also tend to be celibate for Nerds Are Virgins reasons.
- In Jeanne Du Prau's The City of Ember, a reclusive team of engineers and scientists, seeing signs of a coming apocalypse, design, build and stockpile an underground city called Ember, and people it with 200 select individuals to live and procreate there for 200 years. These architects of Ember are called "the Builders" in an Ember that no longer remembers its origins.
- The Adeptus Mechanicus in Warhammer 40,000 are the only people allowed to work on technology. They are also secluded on their own worlds and worship their separate Machine God.
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