This is true of anything you (or anyone) writes or says. Even silence will be self-defined by those who “hear” it. All that should matter is your understanding of the words at the time they are uttered.
Unless, of course, one’s talking about a contract or agreement, in which case all parties involved need to share an understanding. But the Shire Society Declaration is not a contract.
BTW, my prior comments in this thread had nothing to do with the Shire Society Declaration itself, but only with the portions of Sam’s comments that I quoted each time.