With accumulated skills of many lifetimes, he looked on his surroundings through a screen of sophistication and naiveté. Mentats cultivated naiveté. Thinking you knew something was a sure way to blind yourself. It was not growing up that slowly applied brakes to learning (Mentats were taught) but an accumulation of "things I know".
(Chapterhouse: Dune, p. 199)
If you can't tell, this is Duncan Idaho. He can recall all of his lifetimes and this ghola is a mentat. Mentat training, along with all the schools of the Dune series fascinate me, probably because I am an educator. I love this concept that thinking you know something can blind you to breakthroughs. Maintaining humility is so important. I strive to do this but it is difficult to demonstrate to others that you are humble when you are also strong and self-confident. Recently, a couple of dear friends and colleagues pointed out humility as one of my endearing characteristics. They should know who they are and that this was a huge compliment to me.
I believe I have previously mentioned the painting that Odrade cherishes and keeps in her bed chamber: Cottages at Cordeville by Vincent Van Gogh. There is no doubt that the painting she has is the one painted by Erasmus when he was trying to understand humans during Serena Butler's time. Serena had mocked Erasmus. Tried to explain to him that he had not produced art, he had just produced a copy. Erasmus didn't understand since it was a perfect copy.
So during this chapter, Duncan is trying to piece together things that are on the edge of his consciousness that he recognizes are important in some way. The pieces of the puzzle are truly clues to the future of this story but, again, are difficult to comprehend without already knowing where this is going. One of the pieces is a conversation he had with Odrade about the painting. Odrade says to him "That painting says you cannot suppress the wild thing, the uniqueness that will occur among humans no matter how much we try to avoid it." (Chapterhouse: Dune, p. 203). This is what Serena was trying to express to Erasmus! That uniqueness, that wildness, that is what won the war against the machines in the past and will do so again in the future.