The hidden agendas, the politics of hiding intentions behind perceived desires. The idea of feints within feints within feints.
Herbert constructed a complete reality as dense and interesting as Tolkien's Middle Earth; a universe of subtle and not so subtle individuals all driven by their own personal motivations.
It's been many years since I last read Dune, and I remember all these things and more - including the science of ecology and biology of Arrakis. People could (and probably have) written books on the philosophies Herbert describes.
"Fear is the mindkiller . . ."
I had forgotten one thing about this book though.
Some of the writing is beautiful in its description of a sparse and demanding landscape. This is just a random sample that affected me enough to post this reflection:
Paul continued to stare across the basin. He inhaled, sensed the softly cutting contralto smell of sage climbing the night. The predatory bird—he thought of it as the way of this desert. It had brought a stillness to the basin so unuttered that the blue-milk moonlight could almost be heard flowing across sentinel saguaro and spiked paintbush. There was a low humming of light here more basic in its harmony than any other music in his universe.
That bit in the middle:
. . . so unuttered that the blue-milk moonlight could almost be heard flowing across sentinel saguaro and spiked paintbush.
I have only one thing to say about that - "This son of a bitch can write."