It's difficult to fight this cognitive bias that, I think, we all carry—but we must.
It's difficult to fight this cognitive bias that, I think, we all carry—but we must.
Today one can lie with much more impunity, at best tying things up in court for years until the person you lied to gives up, at worst being ordered by the court to make good on the promise and pay some legal costs (maybe).
As your synopsis shows, it's not prestige that forced integrity, it's the fact that others heard, and presumably would enforce such vows, even against a king, that forced integrity, even from a king.
The direct consequence of the king breaking his vow is "only" that the king loses his prestige. But the indirect consequences are severe; "king" is a position from which it is not safe to be removed.
Also learned behavior.
"Before society"? How many times have you seen someone argue that a particular action was morally wrong for no other reason than that it was illegal?