““Lord Vetinari, as supreme ruler of Ankh-Morpork, could in theory summon the Archchancellor of Unseen University to his presence and, indeed, have him executed if he failed to obey. On the other hand Mustrum Ridcully, as head of the college of wizards, had made it clear in polite but firm ways that he could turn him into a small amphibian and, indeed, start jumping around the room on a pogo stick.””
