The values 6 and 9 are regarded as changing lines, i.e. they change into their respective opposite: 6 (Yin) becomes 7 (Yang), 9 (Yang) becomes 8 (Yin). This transforms the original hexagram into another one of the 64 hexagrams.
I regularly receive requests if or why not I do consider the changing lines of the I Ching’s hexagrams in no2DO. My perspective on this issue is as follows: My opinion, working with the I Ching means first of all to thoroughly understand the (original) hexagram. This takes time and effort. However, I consider this step essential and an effort worth taking. For this reason I have expanded the individual hexagrams’ interpretation pages step by step and thus given the users a variety of material at hand.
Without tools or if someone shies away from this effort, it is actually tempting to quickly turn to the changing lines. This is, for example, often the case when solely working with the original texts. Let’s be honest: “Perseverance furthers!” does not say much. It is natural to turn to the changing lines in search of more “meat”. Unfortunately, the texts offered in the changing-lines-section are equally cryptic and bring enlightenment only in few cases. An explanation for this could be that the original texts possibly contain political messages from the times of the texts’ origins. Dominique Hertzer investigated this phenomenon in her book “Das Mawangdui- Yijing”.
However, if you still want to consider the changing lines, I’d offer following advice: The changing lines result in a further, a second hexagram. Once you have worked extensively with the first hexagram, you could then do the same with the second hexagram.