In the Strategies of the Warring States, the retainer Feng Xuan tells Lord Mengchang: “A cunning hare has three burrows, and even so it only just escapes death. Now my lord has one burrow and cannot yet sleep on a high pillow. Let me dig two more for my lord.”
The Handian dictionary explains 狡兔三窟: the cunning hare builds three connected burrows. It is a metaphor for planning thoroughly to escape future disaster.