A Mentat is a profession or discipline in Frank Herbert's Dune universe. For thousands of years, society thought of Mentats as the embodiment of logic and reason. The term 'mentat' was coined by Erasmus, created from the words 'mentor', 'mentee' and 'mentation'.
- "Thou shalt not make a machine in the likeness of a human mind."
Thinking machines were outlawed throughout the universe, and the mentat discipline was developed as a replacement, just as the Bene Gesserit and the Spacing Guild took on functions previously covered by thinking machines. Mentats are humans trained to be able to mimic computers: human minds developed to staggering heights of cognitive and analytical ability.
Unlike computers, however, Mentats are not simply human calculators writ large. Instead, the exceptional cognitive abilities of memory and perception are the foundations for supra-logical hypothesizing. Mentats are able to sift large volumes of data and devise concise analyses in a process that goes far beyond logical deduction: Mentats cultivate "the naïve mind", the mind without preconception or prejudice, that can extract the essential patterns or logic of data and deliver, with varying degrees of certainty, useful conclusions. They are not limited to formulating syllogisms; they are the supreme counselors of the Dune universe, filling roles as menial as archivists and clerks, or as grand as advisor to the Emperor.
The ability to be a Mentat is a talent limited to a small number of people; thus, those with the discipline are prized in whatever role they choose. There are also varying degrees of ability. In Dune, Thufir Hawat is considered to be one of the best mentats known at the time. A Mentat's capabilities can be greatly increased by taking sapho juice, but using it leads to addiction. Sapho is extracted from the root of the Ecaz tree and its use doubles or even triples the Mentat's immense processing power. However, repeated use turns the user's lips a shade of red.
Being a Mentat can be a profession in itself, or the discipline can be added to other roles. In Dune, Paul Atreides is a Mentat duke (later emperor); in Heretics of Dune and Chapterhouse Dune, Miles Teg is a Mentat bashar, or general, who is the most formidable military commander in the known universe. It's also possible to vary the discipline: In Dune, the Tleilaxu create 'twisted mentats' for the Baron Vladimir Harkonnen (Piter de Vries being the most notable example), the purpose of which is a sociopathic Mentat free from the usual constraints of human morality or instinctual considerations (de Vries is, among other things, a sadist and acts as torturer for the Baron). In Dune Messiah, Duncan Idaho is recreated as a ghola, and trained as both a Mentat and as a Zensunni philosopher; he then serves Paul Atreides as the house weapons master. In Children of Dune, he marries the regent, Alia, but is then instrumental in protecting the royal heirs from her, demonstrating that Mentats are rarely simply disinterested observers and counselors.
In God Emperor of Dune, Leto outlaws the order and crushes any renegade training schools he finds. Unlike his execution of historians for the purpose of controlling his legacy and symbolism, Leto never explicitly mentions why he suppresses Mentats, leaving the reader to conclude that it simply plays a role in his larger purpose of oppressing humanity in order to create his Golden Path. The art is not eliminated, however, surviving through underground schools; notably, the Bene Gesserit preserve the art, assuming that Leto knows of this (through his prescience) and approves.
Mentats in the Kevin J. Anderson & Brian Herbert prequels
The backstory for mentats is given in the new prequels written by Kevin J. Anderson and Brian Herbert. The first Mentat was selected by a thinking machine during the time of the Butlerian Jihad. Gilbertus Albans was selected from the Corrin slave pens about 180 B.G. by the independent robot Erasmus. He displayed the first cognitive thinking and computer-like calculation capacity necessary for a Mentat. The term 'mentat' was coined by Erasmus, created from the words 'mentor', 'mentee' and 'mentation' (thinking).
The Mentat Mantra
"It is by will alone I set my mind in motion. It is by the juice of Sapho that thoughts acquire speed, the lips acquire stains, the stains become a warning. It is by will alone I set my mind in motion."
This mantra is a creation of Lynch and does not appear in the books, though in the first book there is mention that Thufir Hawat has cranberry stained lips due to sapho juice.
The same Mantra is also recited by the Harkonnen Mentat Hayt in the beginning of the House's campaign in Dune 2000 before briefing the player on the first mission.