63 The Yî is a book of wide comprehension and great scope, embracing everything. There are in it the way of heaven, the way of man, and the way of earth. It then takes (the lines representing) those three Powers, and doubles them till they amount to six. What these six lines show is simply this,—the way of the three Powers.

64 This way is marked by changes and movements, and hence we have the imitative lines. Those lines are of different grades (in the trigrams), and hence we designate them from their component elements. These are mixed together, and elegant forms arise. When such forms are not in their appropriate places, the ideas of good fortune and bad are thus produced.