I returned from meditation to watch a TV program about Islamic art with images of Paradise as an oasis. Sf readers are reminded of the desert planet, Dune, with its water religion, Jihad and Empire. I classify Dune alongside Foundation and Lensman as a work that aspires to be what Poul Anderson's History of Technic Civilization is, a substantial account of civilization on an interstellar scale.
Anderson's Terran Empire, Merseians and Aeneas are more plausible than the Galactic Empire, the Eddorians and Dune, respectively. Also, Anderson's Danellians, Neldorians and Time Patrol beat EE Smith's Arisians, Eddorians and Galactic Patrol. I suggest that it is important to direct any inquirers about sf towards Anderson rather than towards certain better known names. Dune has had a feature film and a TV series. Foundation is on sale everywhere. The Technic History and the Time Patrol series need to be kept in print.