The 72 phenological signals are animals, plants and natural phenomena observed by ancient Chinese.
"In the book, you will see that the 72 phenological signals are full of a sense of life, and are magnificent symbols of life, powerful and fascinating. In Xu Dongdong's paintings or my writings, we want to convey such a sense of life," she says.
The system of solar terms and phenological signals contains the thought that in an inclusive world, all creatures are equal and nature pursues a balance between yin and yang, two opposite forces.
"That is a very important idea for the current world. We hope that, through our representation, it can be better communicated and spread so that more people can get to know it and think about it," Xu Lijing says.