The time at which the Changes came to the fore was that in which the house of Yin came to an end and the way of the house of Chou was rising, that is, the time when King Wên and the tyrant Chou Hsin were pitted against each other.
This is why the judgments of the book so frequently warn against danger. He who is conscious of danger creates peace for himself; he who takes things lightly creates his own downfall. The tao of this book is great. It omits none of the hundred things. It is concerned about beginning and end, and it is encompassed in the words "without blame." This is the tao of the Changes.
King Wên, the founder of the Chou dynasty, was held captive by the last ruler of the Yin dynasty, the tyrant Chou Hsin. He is said to have composed the judgments of the different hexagrams during his captivity. Because of the danger of his situation, all these judgments emanate from a caution that is intent on remaining without blame and thus attains success.