Personalize navigation, not truth guards against one of the gravest dangers an AI-mediated information system creates: the invisible personalization of civic reality. Commercial systems already show different people different informational worlds, and applied to civic information that becomes catastrophic — one population shown reassurance, another warnings, another kept from hearing of a controversy at all, none of them aware their picture has been shaped.
Common core, personalized path
The rule keeps two things apart. Personalization of navigation — helping a participant reach, filter, and comprehend what is relevant to them — is genuinely useful. Personalization of truth — silently altering the underlying facts presented to different groups — is corruption of the shared reality a society needs to govern itself. So materially important civic signal should have a common public core that everyone can reach, whatever their personalized route into it. It is the civic-scale companion of keeping public evidence inspectable beneath summaries, so that AI becomes an information navigator rather than an epistemic sovereign.