Brotherhood of Logicians

The Brotherhood of Logicians was an assemblage of intelligent humans who emphasised pure logic. (TV: The Tomb of the Cybermen)

The Brotherhood hired Joylove McShane and Yellow Stinker to obtain Cybermen on Grot. Joylove and Stinker were unsuccessful in their job. (COMIC: Junk-Yard Demon II)

Members Eric Klieg and Kaftan financed an archaeological expedition to the cyber-tombs of Telos. They believed they could form an alliance with the Cybermen to help the Brotherhood seize power, but they were both killed by the Cybermen. (TV: The Tomb of the Cybermen)

Behind the scenes
The tongue-in-cheek article "You Know Our Ways" by Jonathan Morris in DWM 504 is formatted as an email sent to the Croydon and Bromley branch of the Brotherhood of Logicians concerning a recently acquired infostamp containing information on the Cybermen.