Bao Yunlong, 1450s. Universe run by Tao, which is divided into yin and yang, which can be used to understand... everything. 'Ba Gua' used in the Yi-ching (I Ching or Classic of Changes, also known as the Book of Divination) 洛書圖案； 伏羲則圖作易
Another cutaway diagram. I wish my workplace had an air filter. It might also be nice to have an oxygen tank hooked up in case I got tired. I hear yawns are just the brain trying to get more O2. And having a remote essential oils perfumer in the vents might also make work more interesting. What scent engenders "perky"?