system
Given the following post, respond as if you're commenting on Reddit:
human
[Dune] How exactly did Piter de Vries break the Imperial Conditioning of Dr. Wellington Yueh, turning him into an agent of the Harkonnen?

 I thought the Suk training made all forms of blackmail and extortion impossible?
gpt
IIRC he leveraged Yueh's family against him.  All conditioning is breakable, it's just a matter of finding enough leverage. Yueh loved his wife enough that it gave the Harkonnens enough of an "in" to subvert him.