How we cite our quotes: (Chapter.Paragraph)
Quote #7
A tank-brain, the Baron thought. Muscle-minded tank-brain. [The Arrakis people] will be bloody pulp here when [Rabban's] through with them. Then, when I send in Feyd-Rautha to take the load off them, they'll cheer their rescuer. (26.208)
The Baron Harkonnen uses tradition as a political tool. First, he creates the tradition that Rabban is an awful leader. Then he breaks his own tradition by installing Feyd-Rautha. Clever, Baron, very clever indeed.
Quote #8
"They obey the preservation of the tribe," [Stilgar] said. "It is the way we choose among us for a leader. The leader is the one who is strongest, the one who brings water and security." (32.24)
Evolution meets tradition and custom in this quote. The Fremen traditionally choose leaders who will preserve the tribe in the same way that animal groups have leaders to ensure their own survival. The best part? No stupid bumper stickers.
Quote #9
[…] Jessica nodded, recognizing the ancient source of the [funeral] rite, and she thought: The meeting between ignorance and knowledge, between brutality and culture—it begins in the dignity with which we treat our dead. (34.69)
Jessica notes another aspect of funeral rites in relation to traditions and customs. According to this quote, it's what separates the cultural us from the more primal us still tucked within our brain.