The dead are gone, driving the crane west is like a dream, and the world is cold. what's the meaning

"The dead are gone, driving a crane to the west is like a dream, and the world is like a tower" is a proverb of China, which means that the dead are gone, like a crane to the west, life is as wonderful as a dream and as unreal as a tower. This proverb expresses deep thinking and understanding of life impermanence.