This term means to observe images of phenomena or those of hexagrams. "Images" refer to the appearance of phenomena that can be seen, but have no fixed form. Images of nature, such as the sky or weather, represent the inherent features of humans and events and the laws governing their changes. People in ancient China created various systems of images such as hexagram images to describe images of natural phenomena. "Observing images" calls for closely examining images to understand the laws governing the movement of nature and society.

When Fuxi was the ruler under heaven, he looked up into the sky to observe celestial phenomena and looked down on the land to observe geographical features and examine the images of birds, beasts, and all other things that existed on earth. He selected symbols from the human body close by and from various objects far away, and then invented the eight trigrams to explain the miraculous nature and distinguish the states of all things. (The Book of Changes)

The sages created the system of eight trigrams and 64 hexagrams to observe images. Texts are attached to all hexagrams and hexagram lines to predict disasters or auspicious events, and changes thus occur through the interaction between what is hard and what is soft. (The Book of Changes)