I would surmise the traditional belief of western philosophy thusly:
1) I do not have perfect knowledge.
2) Good, or at least better, ideas will implicitly produce better results over long periods.
3) It is immoral to control the lives of others.
4) Therefore, people can argue for ideas they find compelling, and people are free to choose what they think is best.
5) Furthermore, people must bear the consequences of their decisions.
A further part of this system was that it was necessary for society to be structured such that individual choices do not have an outsized impact on others. This required that the apparatus of the state have specific constraints. It was quite a remarkable belief system, and much has been written about it over centuries.
Okay, but we still have systems in place that routinely make decisions based on determinations about factual statements. There are obvious ones, like determining whether someone murdered someone else, or determining how much money someone made for the purposes of taxation. We don’t just throw up our hands and say “sure, maybe there is objective reality out there, but even if there is, who could possibly decide what is real?”
> A further part of this system was that it was necessary for society to be structured such that individual choices do not have an outsized impact on others
