From the fact that records were written we know that members of those societies could both read and write, we also know that they deemed it important to leave a record for future generations. From the contents of those records, we know of events that occurred in that society however we must take care with any records that are based largely on opinion since they are likely to be biased.
The enlightment ideas are used in both the US bill of rights and in the independendence of Decloration. And it's not they might be missing they just need to be better enforced
