In Tang Dynasty, there lived a person called Chun Yufen, who thought himself a wise man but was not recognized by people then. So he often felt sad and drank down to pass his time.

One day, he was drinking under an old pagoda tree, to the south of his house. he soon fell asleep and had a dream.

In his dream, Chun Yufen met with an atomy who introduced himself to Chun Yufen that he came to invite him to the great Kingdom of Pagoda. Chun Yufen gladly went there with him. He found himself into a fairy world with many red gates, magnificent palaces, luxuriant pavilions and beautiful gardens; in a word, it couldn't be found in the real world.

The king appreciated him very much so that he was named the head of Nanke. Soon after, he married the king's pretty daughter. Chun Yufen was so happy with the life there that he totally forgot his hometown and his family.

But it was not long before the kingdom was invaded by another country and Chun Yufen had to lead the troops to hold out the enemies. Unfortunately his troops were defeated and his wife died. Chun Yufen was badly hit and he felt very disappointed to himself, so he decided to leave the Kingdom of Pagoda. In the end, he was sent home by the atomy. As soon as he arrived home, he woke up to realize what had happened was just a dream, which only took him a short time to have. There lay the half glass of alcohol on the ground in front of him. And there was an ant creeping on one of his feet. Looking down from the little creature he found an ant nest in the old pagoda tree. "Oh, it must have been the ant nest that I entered and took for that kingdom in my dream." he murmured.

The story is often used to say that someone is very happy about something not based on reality. For an example, someone thought he won a lottery and was very happy about it, but actually he did not win anything.