“He who controls the spice controls the universe.”

“The people who can destroy a thing, they control it.”

“Growth is limited by the necessity which is present in the least amount. And naturally, the least favorable condition controls the growth rate”

“If I always behave with propriety, no matter what it costs me to suppress my own desires, then that is the measure of me. Such is the essence of self-control.”

“Leto turned a hard stare at Kynes. And Kynes, returning the stare, found himself troubled by a fact he had observed here: This Duke was concerned more over the men than he was over the spice. He risked his own life, and that of his son to save the men. He passed off the loss of a spice crawler with a gesture. The threat to men's lives had him in a rage. A leader such as that would command fanatic loyalty. He would be difficult to defeat.Against his own will and all previous judgements, Kynes admitted to himself: I like this Duke.”

“Ah! Indeed but! But he consumes too much spice, eats it like candy. Look at his eyes! He might have come directly from the Arrakeen labor pool. Efficient, Piter, but he's still emotional and prone to passionate outbursts. Efficient, Piter, but he still can err. -Baron Vladimir”

“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; they must retain control of leaders.Two: When the populace recognises 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!”