It’s not ordinary ink but cinnabar ink, right? Taoists believe that cinnabar is composed of the pure Yang energy of heaven and earth, so it can ward off Yin evil spirits. And because cinnabar is red in color, it can enter the heart meridian and soothe the soul. Originally, according to the Bagua classification, the red color should be the Li hexagram, but the big red color should be the Qian hexagram, because the big red color is the color of pure Yang. Cinnabar is a pure Yang thing.