About 2500 years ago, when Sakyamuni was sermonizing his disciples, he suddenly quieted down and picked up a flower, smiling to them. The saints looked in wonder at each other, with the exception of Kassapa Thera, who responded by nodding and smiling back at Sakyamuni. This is the famous story of Sakyamuni "Twist Flower Smile". In the Buddhism practice, the preaching of Zen has no form yet with pure intention, and the receiver received the message without even knowing. Li Shan's Rouge series has used images of Chairman Mao, with the artistic conception of "Twist Flower Smile" - nothing is said, but all is expressed.

This artwork is a good representation of Li Shan's popular Rouge series (title has been used from 1989 to 1993). The portrait of Mao in the most handsome period in Yan'an with the mouth holding a rose. Normally the use of Chairman Mao's image has a political association. The painting of the leader in a jesting and humorous way has also reminded us the Mao painted by Andy Warhol. The real intention of Li Shan is the same as in the story of "Twist Flower Smile" - The Artist means nothing political. Instead, he believes that the society has placed too heavy a responsibility on the shoulder of art; in his opinion, art is art itself. His painting of Comrade Mao's is only a comical reflection of history, to relieve the heavy burden of art and to say farewell to the history by using the once sacred object or image.

At the China Modern Art Exhibition held in 1989 at Beijing-National Art Museum, Li Shan became famous for his performance art "Washing Feet". Prior to that, Li once participated in the planning and exhibition of "the First Shanghai Concave – Convex Exhibition" in 1986 and "the Second Shanghai Concave – Convex Exhibition – The Last Supper" in 1988. His Rouge series was recognized as an important symbol of Political Pop Art in the 1990s. The New Art from China: Post-1989, Venice Biennale in 1993, and Sao Paulo Art Biennial in Brazil in 1994 were the key exhibitions where Li Shan's Rouge series gain increasing influence. Different from Li Shan's own expression about his art, the art critic Lu Peng believes that "Li Shan attempts to express his opposed political differences by taking a stance of keeping away from the direct ideology and political confrontation; he obscures his political view through using metaphorical rhetoric. However, in the 1990s of China, within the historical context of political pop art, Li Shan's explanation was largely considered credible. The irony, metonymy, metaphor, jeer, indication, and analogy, which originally belong in the category of artistic rhetoric, were actually a political discourse and an ideological stance. It is in this sense that Li Shan's art is an important part of the political pop art. At a stage of historical transition, Li Shan has sent out the last reminder, with his art, to those who are on the brink of forgetting the history".