The fifth line of Decrease (King Wen 41) is drawn as yin, the numeral six in the old divination manuals. James Legge's translation renders the line as one to whose increase all parties contribute, ten pairs of tortoise shells whose oracle cannot be opposed, great good fortune. The image sits inside a hexagram whose judgment as a whole concerns sincerity in one who practices decrease brings great good fortune, freedom from error, firmness and correctness maintained, advantage in every movement, and even in the use of two small dishes for sacrifice, and this line supplies one stage of that larger reading rather than a complete statement on its own.
Structurally the line stands at the middle place of the upper trigram Gen, mountain in Legge's readings of the eight trigrams, while the lower trigram of the hexagram is Dui, lake in the same traditional set of images. The Great Symbolism of the hexagram reads a marsh beneath a mountain; the superior man restrains his wrath and represses his desires, and the fifth line takes its place inside that combined picture of Dui below and Gen above.
Read on its own the line neither opens nor closes the hexagram's argument. It marks the point where Gen is either forming (in the lower trigram) or completing itself (in the upper), and later interpreters treat its image, The One to Whose Increase All Parties Contribute, as the concrete case through which the hexagram's abstract judgment becomes visible in a single situation rather than a general principle.