Hexagram 50 is named after the ding, a ritual bronze cauldron standing on three or four legs, used for cooking sacrificial offerings and, more importantly, for signifying that the person who owned it had the right to make them.
Ding are among the most substantial physical objects surviving from Shang and Zhou China. They were cast in sets, inscribed, buried with rulers, and treated as regalia; possession of the ding of a dynasty was possession of its legitimacy. That is why this hexagram follows Revolution in the sequence. One figure describes the overthrow; the next describes the vessel of the new order.
The line texts are correspondingly concrete and unusually domestic for a sacred object. The cauldron is overturned so that stale contents can be emptied out, which the text calls fortunate. Its handle is altered and its movement impeded, so that the fat of the pheasant is not eaten. The legs are broken and the prince's meal is spilled, which is called misfortune. There are golden carrying rings, and finally rings of jade.
That mixture, ritual object, cooking pot, broken legs, spilled dinner, is characteristic of the oldest stratum, and it is one of the passages where the distance between the Zhou Yi and the philosophical tradition built on it is easiest to feel. This is a text about an actual pot.
The philosophical reading built on it, the vessel of transformation, nourishment offered to the worthy, the culture that cooks raw material into something civilised, is developed at length in the Ten Wings and is genuinely fine. It is also unmistakably a later reading, and the broken legs and the spilled dinner are what it was built out of.