The chick here has difficulty to break the shell, leading to a prolonged incubation period. This phenomenon is quite common in avian incubation. In Transformed L4, a new Kan trigram appears in lines three,four and five. Kan can be understood either as the egg itself or as danger and crisis. Since the number of eggs is fixed and cannot increase, so this newly appearing Kan trigram can only be read as difficulty and obstruction.

As for the Hidden L4, when the fourth line changes, Qian disappears in lines three,four and five, and a doubled Kan image appears from line 2 to 6. Qian represents vitality, healthy growth and development, and successful incubation, while Kan represents crisis and danger. This shows that the embryonic development encounters a crisis; it is indeed an unfavorable image.

The upper trigram of the original hexagram changes from Gen into Li. Li is an energy opposed to Kan, the embryo. This suggests that the Gen side shifts from a covering and protective energy into an energy that restrains embryonic development. Li also represents a bonding relationship. At this point, it is already the time for the chick to break out of the shell; however, the change from Gen to Li shows that the eggshell, which should have begun to crack, instead becomes reinforced and strengthened. It is like a parent-child relationship: when it is time to let go and allow the child to grow, one instead emphasizes attachment and connection. Thus, the Li-Kan image of Transformed L4 shows that an inappropriate bonding relationship brings danger and difficulty. This is why the text says “Incubation is hindered,” meaning that embryonic development is obstructed.

As for case of incubation, this may mean that the chick embryo’s feathers or beak become stuck to the shell membrane, causing membrane adhesion; or it may mean that the eggshell is too thick, making it difficult for the chick to peck its way out.

Why does the text say “trouble”? “Trouble” means that obstacles increase during action. It does not mean that the matter cannot be completed; rather, it can eventually be completed, but only after obstruction, damage, and cost. Here, the hexagram change contains both a negative and a positive scenario. The I Ching integrates these two scenarios by the logic that the negative scenario comes first, and the positive scenario follows afterward, using the word “trouble.”

The negative scenario corresponds to the “difficult incubation scenario” discussed above. The upper trigram of the original hexagram changes from Gen into Li. Li represents a friendly or bonding relationship that the Kan-side embryo does not need.

Now let us consider the positive scenario. When the fourth line moves, the original hexagram changes into Weiji, while the Hidden Hexagram changes into Jiji. Weiji is the hexagram of a matter that has not yet achieved success, while Jiji signifies a state of successful accomplishment. In Jiji, the lower Li trigram represents overcoming the crisis symbolized by upper trigram Kan. Jiji is a hexagram where the Li energy takes the upper hand, in other words, the obstacle is ultimately resolved, and the chick can still break through the shell.

However, the third, fourth, and fifth lines of the Hidden Hexagram were originally Qian, with Qian representing health and success; after the change, they become Li, and Li represents weakness. This shows that although the obstacle is resolved, the chick’s health may be impaired and become weakened. The focal player therefore has to pay a cost. Combing all these factors, why the text says “trouble.”

Although the focal player encounters obstruction and setbacks in the process of incubation, the obstacle is eventually resolved. This lays the groundwork for the successful breaking of the shell in the next line.