According to Su Wei, one of the curators of the exhibition, the similarity in their techniques is one possible explanation why their paintings are sometimes misunderstood as belonging to the genres of Impressionism or Fauvism.

Yet according to Wang Pengjie, a doctoral candidate of art theory at the Academy of Arts and Design at Tsinghua University, both painters lacked any systematic training in Impressionistic techniques, or had any understanding of the Western concept of modernism. Instead, it seems that the two painters had developed an awareness of Impressionism that actively influenced their work.

At the same time, their creations were also filled with the freehand brushwork of traditional Chinese painting, especially their works of the 1980s, after the duo met Liu Haisu. They appreciated Liu's combination of Western Expressionist techniques and the artistic concept of Chinese literati painting and were greatly influenced by his work.

All through their careers, Zhao and Yang retained their independence when it came to choosing subjects for their paintings, even during the "cultural revolution" (1966-76), when landscape painting was regarded as bourgeois.

During that period they used small wooden boxes to carry paint sets hidden in their clothes as they wandered around Beijing's Yuyuantan Park, Beihai Park and any other parks with relatively loose supervision. They started to paint as soon as there was no one else around.

While Zhao and Yang painted together and supported each other for more than half a century, they managed to retain their distinctive personal characteristics. And although their works are mixed together at the exhibition, it is easy to spot who painted them.

Some of their paintings of landscapes and dreams from the 1980s, which are directly related to their personal emotions, appear to convey a sense of contemporary art.

"I think there are strong tendencies of purity, aestheticism and lyricism in their paintings, which tend to blur the tension between art and time," says curator Su.

Although in poor health, Zhao and Yang are still creating and modifying previous paintings. As Yang once told the media, "Sometimes it takes a lifetime to figure out who you are and what art is. Art is the expression of freedom and everyone is equal before art."

The exhibition will run through July 1.

[email protected]