"Xu viewed himself as a committed heir to Ren's spirit to modernize Chinese art," Zhang says.

Xu once said, "Ren Bonian was the star (artist) of his generation. He was not a scholar (who stuck to the rigid rules of art). He was a poet."

Xu also said what Ren painted was "not the physical appearance but the mentality of the times and the people".

The exhibition that runs through Feb 28 also compares paintings by Ren and Xu that depict similar subjects.

For instance, both portrayed Zhong Kui, a deity who vanquishes evil beings in Chinese mythology.

Xu produced paintings with the same themes to conduct a spiritual dialogue with Ren.