Hexagram 3 is where readers who have started at the beginning first meet the Zhou Yi's actual texture, and it is not what the first two hexagrams prepare them for.
Its lines include a horseman advancing and then retreating, a marriage party that is not a raid, waiting ten years before betrothal, a deer pursued into the forest without a guide, and finally weeping blood. These are not philosophical propositions. They are fragments of Bronze Age life, hunting, marriage negotiation, raiding, mourning, recorded as omen material because a diviner once matched them to an outcome.
This is the Zhou Yi, the core stratum, and modern scholarship places its assembly in something close to its present form somewhere in a wide range from the tenth to the fourth century BC. Edward Shaughnessy has argued for the last quarter of the ninth century, during the reign of King Xuan of Zhou. Other datings within that range are held seriously, and the question is genuinely open.
The philosophical apparatus that most readers meet first, the superior person, the cultivation of virtue, the correspondence of the trigrams to natural forces, belongs to the Ten Wings, a set of commentaries composed centuries later and traditionally ascribed to Confucius. That ascription was already being questioned inside the Chinese tradition by the eleventh century, and no serious scholar now defends it. The Wings are not the Zhou Yi. They are the first great commentary on it, and they are very good, but they are a second voice.