The laws revolving around the king all are matters of honor. When a person controls his lower based desires he leads an honorable life. One who lets his liver do the driving reverses the order. The antithesis of honor. Furthermore, the Gemorah says the liver is entirely made of blood.
Blood only knows itself.
When things don t go its way it gets angry. Bloods borders are very defined. It attacks all intruders. Let s say it s got a one-track mind. This is very unlike emotions and knowledge which are both open, undefined, interactive and influenced by the things around them.