Once, the Han Dynasty dispatched an emissary to the State of Dian (now Yunnan Province) and the State of Yelang (now Guizhou Province).
The King of Dian asked the emissary from the Han Dynasty: "The Han Dynasty and the State of Dian, which is bigger?"
The King of Yelang also asked the emissary in the same way: "The Han Dynasty and the State of Yelang, which is bigger?"
As a matter of fact, the territories of the State of Dian and the State of Yelang were only as big as a prefecture of the Han Dynasty, but they closed their states to the external contact, shut their eyes and stopped their ears, and didn't understand the conditions of the outside world.
Naturally, they didn't know how vast the Han Dynasty was.