From "Manual of Muad'Dib" by the Princess Irulan

It ended up in confusion , Paul thought, staring at the backs of the last men to leave. Always before, Staff had ended on an incisive air. This meeting had just seemed to trickle out, worn down by its own inadequacies, and with an argument to top it off.
For the first time, Paul allowed himself to think about the real possibility of defeat—not thinking about it out of fear or because of warnings such as that of the old Reverend Mother, but facing up to it because of his own assessment of the situation.
My father is desperate , he thought. Things aren't going well for us at all .
And Hawat—Paul recalled how the old Mentat had acted during the conference—subtle hesitations, signs of unrest.
Hawat was deeply troubled by something.
"Best you remain here the rest of the night, Son," the Duke said. "It'll be dawn soon, anyway. I'll inform your mother." He got to his feet, slowly, stiffly. "Why don't you pull a few of these chairs together and stretch out on them for some rest."
"I'm not very tired, sir."
"As you will."
The Duke folded his hands behind him, began pacing up and down the length of the table.
Like a caged animal , Paul thought.
"Are you going to discuss the traitor possibility with Hawat?" Paul asked.
The Duke stopped across from his son, spoke to the dark windows. "We've discussed the possibility many times."
"The old woman seemed so sure of herself," Paul said. "And the message Mother—"
"Precautions have been taken," the Duke said. He looked around the room, and Paul marked the hunted wildness in his father's eyes. "Remain here. There are some things about the command posts I want to discuss with Thufir." He turned, strode out of the room, nodding shortly to the door guards.
Paul stared at the place where his father had stood. The space had been empty even before the Duke left the room. And he recalled the old woman's warning: "—for the father, nothing."
On that first day when Muad'Dib rode through the streets of Arrakeen with his family, some of the people along the way recalled the legends and the prophecy and they ventured to shout: "Mahdi!" But their shout was more a question than a statement, for as yet they could only hope he was the one foretold as the Lisan al-Gaib, the Voice from the Outer World. Their attention was focused, too, on the mother, because they had heard she was a Bene Gesserit and it was obvious to them that she was like the other Lisan al-Gaib.
—from "Manual of Muad'Dib" by the Princess Irulan
The Duke found Thufir Hawat alone in the corner room to which a guard directed him. There was the sound of men setting up communications equipment in an adjoining room, but this place was fairly quiet. The Duke glanced around as Hawat arose from a paper-cluttered table. It was a green-walled enclosure with, in addition to the table, three suspensor chairs from which the Harkonnen "H " had been hastily removed, leaving an imperfect color patch.
"The chairs are liberated but quite safe," Hawat said. "Where is Paul, Sire?"
"I left him in the conference room. I'm hoping he'll get some rest without me there to distract him."
Hawat nodded, crossed to the door to the adjoining room, closed it, shutting off the noise of static and electronic sparking.
"Thufir," Leto said, "the Imperial and Harkonnen stockpiles of spice attract my attention."
"M'Lord?"
The Duke pursed his lips. "Storehouses are susceptible to destruction." He raised a hand as Hawat started to speak. "Ignore the Emperor's hoard. He'd secretly enjoy it if the Harkonnens were embarrassed. And can the Baron object if something is destroyed which he cannot openly admit that he has?"
Hawat shook his head. "We've few men to spare. Sire."
"Use some of Idaho 's men. And perhaps some of the Fremen would enjoy a trip off planet. A raid on Giedi Prime—there are tactical advantages to such a diversion, Thufir."
"As you say, my Lord." Hawat turned away, and the Duke saw evidence of nervousness in the old man, thought: Perhaps he suspects I distrust him. He must know I've private reports of traitors. Well—best quiet his fears immediately .
"Thufir," he said, "since you're one of the few I can trust completely, there's another matter bears discussion. We both know how constant a watch we must keep to prevent traitors from infiltrating our forces . . . but I have two new reports."
Hawat turned, stared at him.
And Leto repeated the stories Paul had brought.
Instead of bringing on the intense Mentat concentration, the reports only increased Hawat's agitation.
Leto studied the old man and, presently, said: "You've been holding something back, old friend. I should've suspected when you were so nervous during Staff. What is it that was too hot to dump in front of the full conference?"
Hawat's sapho-stained lips were pulled into a prim, straight line with tiny wrinkles radiating into them. They maintained their wrinkled stiffness as he said: "My Lord, I don't quite know how to broach this."
"We've suffered many a scar for each other, Thufir," the Duke said. "You know you can broach any subject with me."
Hawat continued to stare at him, thinking: This is how I like him best. This is the man of honor who deserves every bit of my loyalty and service. Why must I hurt him?
"Well?" Leto demanded.
Hawat shrugged. "It's a scrap of a note. We took it from a Harkonnen courier. The note was intended for an agent named Pardee. We've good reason to believe Pardee was top man in the Harkonnen underground here. The note—it's a thing that could have great consequence or no consequence. It's susceptible to various interpretations."
"What's the delicate content of this note?"
"Scrap of a note, my Lord. Incomplete. It was on minimic film with the usual destruction capsule attached. We stopped the acid action just short of full erasure, leaving only a fragment. The fragment, however, is extremely suggestive."
"Yes?"
Hawat rubbed at his lips. "It says: '. . . eto will never suspect, and when the blow falls on him from a beloved hand, its source alone should be enough to destroy him.' The note was under the Baron's own seal and I've authenticated the seal."
"Your suspicion is obvious," the Duke said and his voice was suddenly cold.
"I'd sooner cut off my arms than hurt you," Hawat said. "My Lord, what if . . ."
"The Lady Jessica," Leto said, and he felt anger consuming him. "Couldn't you wring the facts out of this Pardee?"
"Unfortunately, Pardee no longer was among the living when we intercepted the courier. The courier, I'm certain, did not know what he carried."
"I see."
Leto shook his head, thinking: What a slimy piece of business. There can't be anything in it. I know my woman .
"My Lord, if—"
"No!" the Duke barked. "There's a mistake here that—"
"We cannot ignore it, my Lord."
"She's been with me for sixteen years! There've been countless opportunities for—You yourself investigated the school and the woman!"
Hawat spoke bitterly: "Things have been known to escape me."
"It's impossible, I tell you! The Harkonnens want to destroy the Atreides line —meaning Paul, too. They've already tried once. Could a woman conspire against her own son?"
"Perhaps she doesn't conspire against her son. And yesterday's attempt could've been a clever sham."
"It couldn't have been a sham."
"Sire, she isn't supposed to know her parentage, but what if she does know? What if she were an orphan, say, orphaned by an Atreides?"
"She'd have moved long before now. Poison in my drink . . . a stiletto at night. Who has had better opportunity?"
"The Harkonnens mean to destroy you, my Lord. Their intent is not just to kill. There's a range of fine distinctions in kanly. This could be a work of art among vendettas."
The Duke's shoulders slumped. He closed his eyes, looking old and tired. It cannot be , he thought. The woman has opened her heart to me .
"What better way to destroy me than to sow suspicion of the woman I love?" he asked.
"An interpretation I've considered," Hawat said. "Still. . . . "
The Duke opened his eyes, stared at Hawat, thinking: Let him be suspicious. Suspicion is his trade, not mine. Perhaps if I appear to believe this, that will make another man careless .
"What do you suggest?" the Duke whispered.
"For now, constant surveillance, my Lord. She should be watched at all times. I will see it's done unobtrusively. Idaho would be the ideal choice for the job. Perhaps in a week or so we can bring him back. There's a young man we've been training in Idaho 's troop who might be ideal to send to the Fremen as a replacement. He's gifted in diplomacy."
"Don't jeopardize our foothold with the Fremen."
"Of course not, Sire."
"And what about Paul?"
"Perhaps we could alert Dr. Yueh."
Leto turned his back on Hawat. "I leave it in your hands."
"I shall use discretion, my Lord."