Guiguzi was, it seems, a real Chinese philosopher and teacher of the Warring States Period (475-221 BC) who went through an interesting metamorphosis in Chinese folklore. He claimed to have been a diplomat and the teacher of many great diplomats and statesmen. One of his books survives, although I couldn't make heads or tails of the bit I read, it is said to be a practical guide to statecraft emphasizing the need to react quickly to changing circumstances. By the time this porcelain vase was made in the 14th century AD, Guiguzi was mainly remembered as a wizard who rode around in this cart drawn by a tiger and a leopard and could infallibly predict the future using Taoist methods.
I can only hope that since I have failed to become a wizard in my lifetime, I will undergo a similar transformation after my death and be remembered in the 29th century as a sorcerer who traveled the world in the shape of a sparrowhawk, dispensing wisdom to those in confusion, confounding the minds of the wicked, blasting villains with lightning, and comforting the lonely with visions of divine gardens.