Changing line

In the I Ching, a changing line is a line of the hexagram considered unstable, on the verge of turning into its opposite. In a reading, each line receives a value from 6 to 9: 6 (old yin) and 9 (old yang) are changing, while 7 and 8 are stable. Changing lines have their own text, read in addition to that of the hexagram; they are then reversed to obtain a second hexagram describing how the situation is evolving. It is this movement that gives the Book of Changes its name.