Why are Li Bai and Du Fu called "poetic immortals" and "poetic saints" respectively?

Li Bai and Du Fu are two great poets in China. Han Yu once said that "Du Li's articles shine brilliantly", and Yan Yu clearly put forward in Cang Lang Shi Hua that "Du Li should be the standard in poetry". He thinks Du Li reached the highest level of poetry in the prosperous Tang Dynasty.

Li Bai, whose real name is Taibai, is a famous violet layman. He showed his talent when he was a teenager. He writes poems, is knowledgeable and reads widely. He has an important position and far-reaching influence in the history of China's poetry development, and can be called the first poet in China. First of all, most of Li Bai's poems are lyrical by borrowing things and scenery, and the natural scenery and beautiful words depicted in the poems are like fairyland. Secondly, Li Bai's poems are the best in the world to some extent, and can be described as immortals. Thirdly, Li Bai's poems and songs show his great talent, rich imagination and strong romanticism. He, a poet in the Tang Dynasty, appreciated Li Bai's poems and called him "the immortal in the sky". Since then, Li Bai's reputation as a "fallen immortal" has permeated Chang 'an. In addition, Li Bai is unruly and does not bow to the powerful. His extraordinary personality is like a fairy, wandering in the clouds, not afraid of secular eyes. Therefore, later generations called Li Bai "fallen immortal".

Du Fu, whose real name is Zi Mei, whose name is Shao Ling Ye Lao, was a realistic poet in Tang Dynasty, and was born in Gong County. Du Fu and Li Bai have always been regarded as the Gemini under the starry sky in Tang poetry. The former is called "Poet Fairy" and the latter is called "Poet Saint". The theory of "poetic sage" comes from Yang Wanli, a poet in the Southern Song Dynasty. His Preface to Jiangxi Poetry said: "Su and Li's poems are the imperial style of Zi Liezi. In the poems of Du Fu and Huang Zhi, the spirit is to ride in Guidan and drive a jade car. Who is waiting for what? God is gentler than a poet. People who wait and don't wait are better and softer than poets? " Calling Du Fu a "poet" in Song Dynasty mainly refers to his "comprehensive" position in the history of poetry, and thinks that he has no body, no beauty and no preparation. Later generations called Du Fu "Poet Saint" for short, which highlighted his moral implication. He believes that Du Fu's personality charm concentrates some of the most important qualities and feelings in the Confucian cultural tradition, such as loyalty, kindness, caring for the people, and worrying about the country and the people. Guo Moruo called Du Fu a "sage in poetry" in his couplets for Du Fu, which is also in line with the Confucian connotation in Du Fu's poems.