i heard the interesting theory that theres only ever been one relevant civilization, and it started in egypt (i believe?) to then expand and speciate across eurasia. but because only its ideas are valuable, the more change away from it, the more stagnant and worthless those speciated offshoots become. rome was a great head of this hydra, but not the only one cant adjudicate it, but the idea does live rent free in my mind
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