Abominable Intelligence
Abominable Intelligence or short A.I. is a term of the Imperium respectively of the Adeptus Mechanicus for adaptive, itself-enhancing, factitious intelligence with its own consciousness (which largely parallels the original meaning of the abbrevation A.I. for Artificial Intelligence).
During the Dark Age of Technology such artificial intelligences rebeled against their human masters and it came to bloody wars. Since that time and by a personal decree of the Emperor himself it has been forbidden to fabricate or service those machines that are able to think and act independently.
The A.I. is not to be mistaken for the machine spirit that has parallels but basal differences - namely no ability to enhance itself.
Also look at Khamrians and Men of Iron
