The sixth line of Revolution (King Wen 49) is drawn as yin, the numeral six in the old divination manuals. James Legge's translation renders the line as the superior man changes as the leopard changes its spots, while lesser men merely change their faces to show outward obedience; going forward now would be evil, but abiding firm and correct brings good fortune. The image sits inside a hexagram whose judgment as a whole concerns believed in only once it is accomplished, great progress and success, advantage in being firm and correct, so that any occasion for repentance disappears, and this line supplies one stage of that larger reading rather than a complete statement on its own.
Structurally the line stands at the topmost place of the upper trigram Dui, lake in Legge's readings of the eight trigrams, while the lower trigram of the hexagram is Li, fire in the same traditional set of images. The Great Symbolism of the hexagram reads fire in the midst of the waters of a marsh; the superior man regulates his calendar and makes clear the seasons and times, and the sixth line takes its place inside that combined picture of Li below and Dui above.
Read on its own the line neither opens nor closes the hexagram's argument. It marks the point where Dui is either forming (in the lower trigram) or completing itself (in the upper), and later interpreters treat its image, The Superior Man Changes as the Leopard Changes, as the concrete case through which the hexagram's abstract judgment becomes visible in a single situation rather than a general principle.