the golden rule works because of the consequences that come from "eye for an eye."
if you treat people like shit, they will eventually retaliate by treating you like shit, employing "eye for an eye" to validate "the golden rule."
ultimately, utilizing the golden rule will help you avoid eye for an eye.
don't throw acid in another person's face if you don't want it thrown in yours.
in the absence of society and community, eye for an eye is the only form of justice, even if it's not 100% literal.
don't get me wrong, this is very simplified, but nothing is all encompassing and i'm getting my point across in anycase.