Cheng Hao taught that the humane person regards heaven, earth and all things as one body. Wang Yangming developed the idea: the great person feels the suffering of all things as their own, not from deliberation but because the heart is by nature one with them.
One body with all things
The Neo-Confucian teaching that the humane person forms one body with heaven, earth and the myriad things.
Also: wanwu yiti