In Chinese tradition, dreams are conceived of as an experience of the soul that leaves the body during sleep. Immortals have no dreams because they do not have aspirations or desires.
Dreams may foretell good or bad luck. Books interpreting dreams are still in use. The most popular is the book Interpretation of Dreams by Duke Zhou 周公结梦 from c.1050 BCE.
Literally: Southerners do not dream about camels [and] northerners do not dream about elephants.
Dreams do not deviate far from the dreamers' reality and environment.
He who dreams of getting married – his desire for happiness will not be obtained
The dream of the yellow millet
Said of awakening from illusion.
This is based on the following legend from The World inside a Pillow 枕中记 , written during the Tang dynasty (618-907 CE):
At the same time, the innkeeper started cooking millet. Young Lu put his head on the pillow and fell asleep. In his dream, he married a rich and beautiful young woman. Later on he passed the government examinations, achieving the highest marks and gaining a high public position. He had countless farmlands, begot five children who all became high government officials and bore him a dozen grandchildren. All his children and grandchildren married noble spouses and he himself enjoyed a long life exceeding 80 years. When he woke up, he rubbed his eyes, looked around, and saw the innkeeper still cooking the millet.
Thoughts during the day [will become] dreams at night
Sees the grass and the trees as if they were the enemy
Said of one who fails as a result of imagining difficulties.
A parallel expression in Hebrew originating in the Bible:
רואה את צל ההרים כאנשים
Literally: Sees the shadow of the mountains as if they were people.
(שופטים ט, 36: "את צל ההרים אתה רואה כאנשים").
(Judges, 9, 36: "You are seeing the shadow of the mountains as if they were men")
The idiom is based on the following story:
In 383 CE Fu Jian 苻坚 , the King of the State of
秦 , led an army of 800,000 soldiers to attack the State of Qin 东基. After being defeated in the first battle, Fu Jian looked down from the city wall and panicked when he saw the battalions of the army of Eastern Jin. In fact, what he was seeing was nothing but the fruits of his imagination. He saw the trees and the grass as if they were the soldiers of the enemy. As a result, he led his army to a disgraceful defeat. Eastern Jin
梦里坐飞机 - 想头不低; 想得高
Dreams of flying in an airplane – high thoughts
As the (Jewish) sages of blessed memory said:
"אדם ישן כאן ורואה חלום באספמיא"
נידה ל, ב
Literally: Dreams in
("A man is sleeping and sees a dream in
" Nida, 30, 2) Spain
Castles in Spain
Literally: Towers in the air.
Said of a plan or theory with no basis in reality.
This is based on the following story:
Once there was a rich man who asked an architect to build him a three-storey building. When the architect had finished building the first floor, the rich man said to him, "I want only the third floor and I am not interested in the first and the second floors". In response, the architect asked, "Without the first and second floors, how can I build the third floor?" Shaking his head, the architect packed his belongings and left.
A parallel Jewish expression:
מגדל הפורח באוויר (סנהדרין קו).
A tower flying in the air (Sanhedrin, 106).
The peach blossom springs
Said of an idyllic vision of unspoiled wilderness. A kind of paradise. Utopia.
This originates in the following story written by the poet Tao Yaoming 陶遥明(365-427 CE) :
During the Eastern Jin 东晋 dynasty (317-420 CE) there was an old fisherman in the Wu Ling 武陵  region. One day he went out to fish and as his boat made its way upstream, he lost his way. Then he saw in front of him a forest of peach trees in full blossom. Curious, he continued sailing till he came to the end of the forest, where he saw a mountain and, at its foot, a small cave. Upon entering the cave a whole world was revealed before his eyes: people living peacefully and happily in harmony, with no fights or arguments. The old were resting and the young playing. When these people saw him they asked him not to tell anybody what he had seen. After returning home, he nonetheless told the peasants about his experience. Not believing his story, they followed him to see the place, but could not find it.