Thinking you know something is a sure way to blind yourself.

There's an unwritten compact between you and the reader. If someone enters a bookstore and sets down hard earned money (energy) for your book, you owe that person some entertainment and as much more as you can give.

The mistakes (of leaders) are amplified by the numbers who follow them without question. Charismatic leaders tend to build up followings, power structures and these power structures tend to be taken over by people who are corruptible. I don't think that the old saw about 'power corrupts and absolute power corrupts absolutely' is accurate: I think power attracts the corruptible.

When I need to identify rebels, I look for men with principles

Law of the Minimum: "The worst potential competition for any organism can come from its own kind. The species consumes necessities. Growth is limited by that necessity which is present in the least amount. The least favourable condition controls the rate of growth."

Once human beings realize something can be done, they're not satisfied until they've done it.

The scarce water of Dune is an exact analog of oil scarcity. CHOAM is OPEC.