On a lark I did some animation silliness today. The typical explanation for the taijitu, or the yin-yang symbol ( ☯ ), mentions how dark and light are intertwined, one leads to the other in a symbiotic wax-and-wane cycle, and one contains the seed of the other inside. Well, said I, I wonder what this wax-and-wane cycle would look like if the taijitu was rotating and you took the average grayscale value of the portion of the symbol passing at the zenith part. Who wouldn’t wonder that?
To make that more obvious, I’ve prepared this anigif, which contains three parts: a rotating taijitu, a cropping of the topmost sliver of the symbol from the centerpoint up (indicated by the red box in the first part), and the average grayscale value of that sliver:
So, basically, as the Wheel of Earth and Heaven rolls ponderously around, there are alternating times of lightness, darkness and shades in-between. I will leave you with a stand-alone gif of this interplay for your own amusement (caution: may not be synced with the above animation):