I must not fear.
Fear is the mind-killer.
Fear is the little-death that brings total obliteration.
I will face my fear.
I will permit it to pass over me and through me.
And when it has gone past I will turn the inner eye to see its path.
Where the fear has gone there will be nothing.
Only I will remain.
Dune is more mythos than novel and has spawned innumerable spin-off books, films and mini-series. As such, it is something of a challenge to review the original works, Dune World (1963-4) and The Prophet of Dune (1965), most commonly referred to as the amalgamated novel Dune, first published in this format in 1965 and winner of the Hugo and Nebula awards for best novel in the same year.
At over 550 pages in this edition (the first hardback entry in the main SF Masterworks series, presumably for rights reasons), Dune is often lazily referred to as 'science fiction's Lord of the Rings'. There is little real merit to this analogy: yes, it is a study of good versus evil; yes, there are a number of rich and overlapping cultures portrayed in the book (the empire with its Houses and Guilds, the warped Buddhism of the Bene Gesserit 'witches', the near-eastern influences suffusing the culture of the Fremen desert tribes, the sandworms of Arrakis and the consciousness-altering spice melange drug that they make) but other than the fact that both works are engaging tales, expertly told, there is little more to say.
Dune is on one level a personal, political, emotional and spiritual bildungsroman, tracing the passage of Paul Atreides, son of Duke Leto Atreides and the Lady Jessica, Bene Gesserit and concubine to the Duke, from usurped ducal heir to the Lisan al-Gaib, a prophet who will lead the native Fremen people of Dune on a program of land reclamation, turning the desert to verdure.
However, to describe the novel only in these terms does a disservice to its dense and complex structure, and each reader will find a different path through it. I was particularly struck by the contemporary (i.e. mid-'60s) significance of Herbert's insistence that women (the Bene Gesserit) are covertly running the political world through their machinations, interventions, and breeding programs. To me, this seemed less to signify a progressive social emancipatory urge on the author's part than to disclose (perhaps unconsciously) a certain Cold War paranoia, with women taking the place of the Russian agents and the KGB.
Note: Dune was the first entry in the 2001 hardback SF Masterworks series, and the seventy first entry in the numbered SF Masterworks series (cased). The same cover image was used for both editions.