One important concept due to Old Bill is the routine
: meaning a character (like the Old Doctor
or the County Attorney) that will occasionally take hold of you, and force you to perform
Burroughs had several routines, most of which I suspect found their way into his books, like "The Man Who Taught His Asshole To Talk"
or, of course, the cool hardened Junkie.
Entirely without relation, or maybe not, let me mention that Burroughs killed his wife Joan in Mexico City, by playing William Tell when drunk. He shot her with a handgun, while trying to break a glass she had on her head.
Later on, he wrote that this happened because an external force took hold of him and shifted his aim.