Twisted Mentat: the human computer built without a conscience

Twisted Mentats were Mentats who originated on the planet Tleilax, produced by the Bene Tleilax rather than admitted to the legitimate schools that had grown out of the Butlerian Jihad. They differed from ordinary Mentats in every characteristic that was not essential to pure computational ability, and those differences were bought and paid for. Body structure, emotional nature and psychological make-up were all altered according to a customer's order, which meant a Great House could commission a human computer shaped to its own appetites. The most notorious example was Piter de Vries, the sadist who calculated the destruction of House Atreides on behalf of Baron Vladimir Harkonnen.

The ethical framework and its removal#

The Mentat discipline arose as a replacement for the thinking machines outlawed after the Butlerian Jihad, and its practitioners were far more than human calculators. A Mentat gathered enormous quantities of data and produced concise analysis through a process that went well past logical deduction, cultivating what was called the naive mind, a mind without preconception or prejudice, capable of drawing the essential pattern out of the material and delivering useful conclusions with varying degrees of certainty. Highly skilled practitioners could push that faculty into hypothesising, strategising and tacticising probable outcomes with a clarity that approached prescience, though never matching it.

Mentats were required to operate within an ethical framework. For certain purposes that framework was not wanted, and the Bene Tleilax existed to supply what was not wanted. They conditioned Mentats to be twisted, which meant those individuals could hypothesise, strategise and tacticise entirely free of ethical restraint or limitation. The raw computational ability was unchanged. What had been removed was the part that would refuse.

Made to order on Tleilax#

The distinction between a school Mentat and a Tleilaxu Mentat began at the point of selection. Mentat training capitalised on an individual's natural characteristics and benefited from them, so the standard practice of the legitimate schools was to select admirable people as students and build the discipline on top of what was already there. Those schools did breed for certain characteristics of their own, but the traits they sought were comparatively benign and were not the product of genetic engineering.

Tleilaxu Mentats were a separate breed altogether, displaying artificially produced characteristics that had been specified in advance. That the resulting traits were so often odious said as much against the Great Houses who patronised the Bene Tleilax as it did against the Tleilaxu Masters who filled the orders. A House that commissioned a twisted Mentat was describing, in the specification, exactly what it wanted a mind to be willing to do.

Piter de Vries and the ruin of House Atreides#

The Bene Tleilax do not appear to have lacked customers, and it is likely that a considerable number of twisted Mentats were at work across the Imperium. The one whose work reshaped an era was Piter de Vries, an ambitious and impatient sadist whose bloodlust disturbed even the Baron he served.

Piter was the Baron's strategist, assassin and torturer, and he was unsympathetic to Harkonnen ideals of supremacy. His own motivation ran to a single obsession, the acquisition of Lady Jessica as a personal possession. His work for House Harkonnen was accordingly cold. He arranged a half-genuine attempt on the young Atreides heir's life, planted evidence that implicated Jessica as the traitor in the Duke's household, and then produced the piece nobody had thought possible by breaking the Imperial Conditioning of a Suk doctor in ducal service. That plot delivered Leto Atreides I into the Baron's hands.

His talents did not extend to infallibility. Piter predicted that Jessica would bear the Duke a daughter rather than a son, reasoning from ordinary Bene Gesserit breeding practice and from the Emperor's own lack of male heirs, and he was wrong. He also failed to detect the poison tooth that the doctor he had broken had planted in the captive Duke's mouth. When Leto crushed it in the dining hall of the Arrakeen residency, the airborne toxin filled the room. The Baron escaped. Piter did not.

Other twisted Mentats in service#

Piter was the most visible of his kind but not the only one. Grix Dardik was a fanciful twisted Mentat in the service of Count Hasimir Fenring on Arrakis, and unlike most Mentats his mind was capable of superior novelties, producing the kind of unorthodox connection that a conventionally trained practitioner would never have reached. The variation is instructive. Twisting was not a single procedure with a single outcome. Each product carried whatever alterations its buyer had specified, so the category covered minds that had been bent in quite different directions.

Against these stood the exclusive advisers of the honest tradition, among them Thufir Hawat of House Atreides, whose innate ability was formidable enough that the Padishah Emperor feared him. The contrast between Hawat and Piter, the two Mentats who directed opposing sides of the same feud, was the contrast between the two ways of making one.

Repugnance and demand#

Because Tleilaxu products were so often warped and bizarre in nature, twisted Mentats came universally to be regarded as objects of repugnance. That reaction functioned as a social taboo rather than as any real barrier, since their skills remained in demand throughout the days of the Imperium and the Bene Tleilax kept filling orders.

The pattern of their employment argues that the twisting was narrower than the taboo suggested. Twisted Mentats were routinely trusted with the innermost secrets of Great Houses, which indicates that whatever psychological damage had been engineered into them did not extend to unreliability. A man as perceptive as Baron Vladimir Harkonnen would not have confided the ruin of his greatest enemy to a mind he expected to betray him. Piter, for his part, understood the arithmetic of his own position. When the Baron threatened to have him killed on Giedi Prime, Piter was unconcerned, knowing his value made the threat empty, and he told his master plainly that he was more efficient than the thinking machines of the old empire had been.

The claim that the twisting was a hoax#

A later and more unsettling assessment came from the ghola Mentat Duncan Idaho, who had been made in the Tleilaxu tanks himself and knew the sellers from the inside. He suggested that the twisting was a hoax maintained by the Bene Tleilax. By his account the conditioning was very fragile, and twisted Mentats retained their own selfdom and dignity beneath it, refusing to be absolutely controlled by the Great Houses that had bought them.

If that reading was correct, the Bene Tleilax had been selling something other than what their customers believed they were buying. The purchasers thought they were acquiring an instrument with the conscience removed. What they actually received was a Mentat who could be relied upon to reason without restraint but who was never wholly theirs, and who kept, somewhere underneath the alterations, an interest of his own. Piter de Vries pursuing Jessica while his master pursued Arrakis fits that description exactly.