The origin of wordless gobbledygook

Wordless gobbledygook: a metaphor for obscure books or knowledge.

There are two different legends about wordless gobbledygook:

Legend: The Book Without Words is said to be a wonderful scroll of people who studied divination in Zhouyi in past dynasties. After getting a glimpse, they want to pass it on to future generations, but they are worried that the open-air opportunities will be condemned by God or used by evil people, which will bring disaster to the world. They don't use words, but use pictures to make future generations understand.

Legend has it that when Guiguzi's master ascended to heaven and became immortal, he left a roll of bamboo slips with the word "heavenly book" written on it. When I opened it, there was not a word from beginning to end, and Guiguzi was puzzled for a moment. I have lived alone with Master for nine years, and my feelings are getting deeper and deeper. Today, Master suddenly left, feeling that he had nothing to lose, and his heart was empty, so he got into his cave and fell asleep. But how can I sleep, tossing and turning, always thinking about the bamboo slip without words, until dark, the bamboo slip is still rolled, rolled, rolled, and inexplicable. He simply climbed up, lit the torch of Song Ming, and jumped up by the light. Bamboo slips are shining with golden light, and tadpoles' lines are shining. Guiguzi sighed: "Is this the' golden book' passed down from generation to generation?"