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Comparison

Persistent elite dominance

Among the non-human great apes, power hierarchies (some hereditary) have been observed.
kazoku and samurai in Japan - TW1.
Communist china - TW.
“Son also rises” by Gregory Clark - YT-TED, C2020 documents the inheritability of social status.
- In fact, prior to 1800-s in England, rich had higher fertility than the poor; reverse in Qubec.
Oxbridge attendence in England - TW1.

Occupational impurity and separation

Burukumin in Japan, Cagots in France, “dishonorable people” (unehrliche Leute) in early modern Germany, similar groups in Arabia, Yemen and Korea, practicing muslims and christians in India [A]

Ritual purity

“najasat” in Islamic socieites (spiritual pollution, separate from “kesafat”, physical uncleanliness).
A 3rd-century CE account of the Egyptian Priesthood and the lives of its priests by Porphyry in his Abstinence, Book 4 illustrating:
- much admired, exclusive, mostly-isolated state [TW1, TW2]
- self-restriction in diet, attire, countenance, travel [TW]
- regular engagement in rituals
- engagement in geometry etc.. in leisure TW3