“A large population held in check by a small but powerful force is quite a common situation in our universe. And we know the major conditions wherein this large populace may turn upon its keepers–

“One: When they find a leader. This is the most volatile threat to the powerful; the must retain control of leaders.

“Two: When the populace recognizes its chains. Keep the populace blind and unquestioning.

“Three: When the populace perceives a hope of escape from bondage. They must never even believe that escape is possible!”

Bene Gesserit philosophy on threats to minority rule
Frank Herbert, Children of Dune