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

He's faking uncertainty! Jessica thought.
With his deeper truthsense, Paul caught the underlying motive, had to use every ounce of his training to mask his excitement. There is enough water! But Kynes doesn't wish it to be known .
"Our planetologist has many interesting dreams," Bewt said. "He dreams with the Fremen—of prophecies and messiahs."
Chuckles sounded at odd places around the table. Jessica marked them—the smuggler, the stillsuit manufacturer's daughter, Duncan Idaho, the woman with the mysterious escort service.
Tensions are oddly distributed here tonight , Jessica thought. There's too much going on of which I'm not aware. I'll have to develop new information sources .
The Duke passed his gaze from Kynes to Bewt to Jessica. He felt oddly let down, as though something vital had passed him here. "May be," he muttered.
Kynes spoke quickly: "Perhaps we should discuss this another time, my Lord. There are so many—"
The planetologist broke off as an uniformed Atreides trooper hurried in through the service door, was passed by the guard and rushed to the Duke's side. The man bent, whispering into Leto's ear.
Jessica recognized the capsign of Hawat's corps, fought down uneasiness. She addressed herself to the stillsuit manufacturer's feminine companion—a tiny, dark-haired woman with a doll face, a touch of epicanthic fold to the eyes.
"You've hardly touched your dinner, my dear," Jessica said. "May I order you something?"
The woman looked at the stillsuit manufacturer before answering, then: "I'm not very hungry."
Abruptly, the Duke stood up beside his trooper, spoke in a harsh tone of command: "Stay seated, everyone. You will have to forgive me, but a matter has arisen that requires my personal attention." He stepped aside. "Paul, take over as host for me, if you please."
Paul stood, wanting to ask why his father had to leave, knowing he had to play this with the grand manner. He moved around to his father's chair, sat down in it.
The Duke turned to the alcove where Halleck sat, said: "Gurney, please take Paul's place at table. We mustn't have an odd number here. When the dinner's over, I may want you to bring Paul to the field C.P. Wait for my call."
Halleck emerged from the alcove in dress uniform, his lumpy ugliness seeming out of place in the glittering finery. He leaned his baliset against the wall, crossed to the chair Paul had occupied, sat down.
"There's no need for alarm," the Duke said, "but I must ask that no one leave until our house guard says it's safe. You will be perfectly secure as long as you remain here, and we'll have this little trouble cleared up very shortly."
Paul caught the code words in his father's message—guard-safe-secure-shortly . The problem was security, not violence. He saw that his mother had read the same message. They both relaxed.
The Duke gave a short nod, wheeled and strode through the service door followed by his trooper.
Paul said: "Please go on with your dinner. I believe Doctor Kynes was discussing water."
"May we discuss it another time?" Kynes asked.
"By all means," Paul said.
And Jessica noted with pride her son's dignity, the mature sense of assurance.
The banker picked up his water flagon, gestured with it at Bewt. "None of us here can surpass Master Lingar Bewt in flowery phrases. One might almost assume he aspired to Great House status. Come, Master Bewt, lead us in a toast. Perhaps you've a dollop of wisdom for the boy who must be treated like a man."
Jessica clenched her right hand into a fist beneath the table. She saw a handsignal pass from Halleck to Idaho , saw the house troopers along the walls move into positions of maximum guard.
Bewt cast a venomous glare at the banker.
Paul glanced at Halleck, took in the defensive positions of his guards, looked at the banker until the man lowered the water flagon. He said: "Once, on Caladan, I saw the body of a drowned fisherman recovered. He—"
"Drowned?" It was the stillsuit manufacturer's daughter.
Paul hesitated, then: "Yes. Immersed in water until dead. Drowned."
"What an interesting way to die," she murmured.
Paul's smile became brittle. He returned his attention to the banker. "The interesting thing about this man was the wounds on his shoulders—made by another fisherman's claw-boots. This fisherman was one of several in a boat—a craft for traveling on water—that foundered . . . sank beneath the water. Another fisherman helping recover the body said he'd seen marks like this man's wounds several times. They meant another drowning fisherman had tried to stand on this poor fellow's shoulders in the attempt to reach up to the surface—to reach air."
"Why is this interesting?" the banker asked.
"Because of an observation made by my father at the time. He said the drowning man who climbs on your shoulders to save himself is understandable—except when you see it happen in the drawing room." Paul hesitated just long enough for the banker to see the point coming, then: "And, I should add, except when you see it at the dinner table."
A sudden stillness enfolded the room.