I discuss a matter of which someone would call me an expert on paper with another 'expert', and we throw at each other dozens of sheets of paper and links to sustain our points. Each link has been reviewed and found worthy by another 10 experts, because of a general consensus based on a sheet of paper by yet another expert.
I ponder modern history on the basis of some story i read in my older history books, filled with notions of happenings i never saw with my eyes having to trust someone that himself has read it from yet another source (and so on).
Then we visit an old structure and it's just like it is written in our history book; therefore, not that we needed it, it's all confirmed and real.
And yet this is all a story that was put in my head by other people writings, mostly. A cathedral could have had another rationale, with perhaps a public decoy-like reason that was popularized and made it to history; some stuff may never be happened, etc.
How much can we really say that 'we know' in the utmost sense of 'knowing'? I guess it has to be estimated on a range to not get mad.
We can say 'for sure' there is a conflict in ukraine now, but we can see in real time the reasons may well be totally different by what is portrayed, etc.
Going back, what can we 'know' to be sure of? history, science, how to assess what's real independently?
It's a bit of a rambling, i know, but i wanted to highlight the neuroticity of the 'mental world' everyone ends up living in.