I can't remember the book this is in and I don't really know any parts of the exact wording, but a character was telling someone else a story about 3 men. (It may have been the Patrician from Discworld telling it to Vimes or Moist von Lipwig, but I'm not sure).
One of them had money, one had political power and one a weapon, and he asked him who out of these 3 men had the most power.
There may have been some question along the lines of: "kill this man and I will give you [something]."