Lin was a master of color. "He once joked that he was a 'slave' of color. He had experienced too much. The ups and downs of life, and the sadness and happiness had turned into these colors of brightness and darkness in his paintings", Wu once remarked of his teacher's work.

Wu himself was pursuing what he saw as the ultimate beauty of form, and the varied combinations of geometric structures, lines and dots define work in which he melded Western abstraction with Chinese minimalism and symbolism.

One famous example on show is the Shizilin, or Lion Grove Garden, a colored ink painting done in 1983, that is nearly 3 meters in length.

Currently part of the collection of Shanghai's China Art Museum, the painting depicts jiashan, or a faux mountain, an important part of classical Chinese gardens that are piled with hollow rocks of varying sizes, shapes and textures. The "mountain" occupies over four-fifths of the whole composition. In a departure from the traditional way of depicting gardens, Wu used ink lines and colored dots to represent the rocks and the rock mountain, and it is this bold, new style that distinguishes the painting as a brilliant example of the depiction of the classical private gardens of Suzhou, Jiangsu province.

Wu followed in Lin's footsteps becoming an educator. He taught first at the Central Academy of Fine Arts, and then at the Central Academy of Arts and Design, today's Academy of Arts and Design, at Tsinghua University, before retiring in 1985.

"What he taught was not knowledge, but how to imagine, create and express beauty in boundless forms," says Liu Jude, head of the Wu Guanzhong Art Research Center at Tsinghua University.

Xu says Lin and Wu's work is a glimpse of the expansive nature of modern Chinese art. "As it absorbed elements of Western art, it didn't forget its own cultural traditions … which inspired artists to explore and create, and became a foundation on which new forms of art thrived," she says.

Wu once said: "Tradition is …like a big river.

"It flows upstream against currents, experiencing collisions along the way, constantly transforming itself in the process."

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