If you follow any "authority" to its logical end, it largely boils down to a consent of the governed, or various degrees of coercion.
Its the idea behind "fake it until you make it". People accept the "fake" long enough that either "fake" no longer accurately describes you, because you've bootstrapped in to legitimacy, or the accepting people aren't savvy/interested/powerful enough to discern your inauthenticity.
Its the idea behind "fake it until you make it". People accept the "fake" long enough that either "fake" no longer accurately describes you, because you've bootstrapped in to legitimacy, or the accepting people aren't savvy/interested/powerful enough to discern your inauthenticity.