I've only read the first 100 pages or so of the Butlerian Jihad, but so far, I'm getting the feeling that the robot Erasmus is a weird mechanoid amalgamation of the characters of Count Hasimir Fenring, and Mentat Piter DeVries, from the other Dune books. To show you why I think this is so:

1.) Fenring is the main advisor to the emperor of the known universe, Shaddam IV; Erasmus advises Omnius, who is technically the emperor of the known universe,
2.) Both Fenring and DeVries are willing to kill people even "just to stay in practice", or as sport; Erasmus, kills his cook "to suprise him", then vivisects three of his household staff, because it's "artistic",
3.) Once again, both Fenring and DeVries, believe that their bosses are lacking in some areas, Fenring believes that Shaddam lacks tact, DeVries that Baron Harkonnen lacks "finesse"; Erasmus, believes that Omnius lacks understanding,
4.) All of them, Fenring, DeVries and Erasmus, are convinced that their masters can be narrow minded.

Any other views on this subject?
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