Superstition
Superstition was a belief system.
Before the Intuitive Revelation, Gallifrey was a matriarchal society ruled by the Pythia through magic and superstition. After the Revelation, it became patriarchal and promoted reason and science. (PROSE: Cat's Cradle: Time's Crucible)
People from the West Country were sometimes characterised as being traditional and somewhat superstitious. (PROSE: The Devil Goblins from Neptune)
Captain Alexander Marfleet inherited a superstitious nature from his father. (AUDIO: The Flying Dutchman)
The people of Sarn descended from a high-technology society into tribalism and superstition. They worshipped Logar, God of the Fire Mountain, and sacrificed unbelievers in fire. (TV: Planet of Fire)
The Architect was known to have been a Devotee of Apeiron though knowledge of this was kept secret amongst the Gallifreyans due to the superstition involved with being associated with such a cult at the time. (PROSE: The Ancestor Cell)
Friday the 13th was considered unlucky according to Rose Tyler. (COMIC: Triskaidekaphobia)
Peter Dickson's mother was superstitious, believing that black cats were unlucky, especially if they had green eyes. Her son didn't share her belief. (PROSE: The Clockwise Man)
Dalek Sec of the Cult of Skaro dismissed ghosts as superstition. (TV: Doomsday)