Interesting in this context is completely divorced from morally good/bad. Could be any group from any area at any time in history. I’ll start with a few, followers of the cult of pythagoras, contemporary black Hebrew Israelites, antiracist skinheads and the Amish (neo-luddites in general). Don’t be racist or a prick to other people discussing.


Luckily I know at least some philosophical basics, so I do think I understand your talking points. (And essentially Descartes’ cogito ergo sum, lead me on this extreme path of epistemological masochism.)
Infinity is actually a very good example I think, that shows us we are perceiving something weirdly. There exist no measurable, conrete infinity in the physical universe, as far as we know; even the space itself has its limits. Yet we understand the concept of infinity, so it exists in some form, in the reality we are perceiving. But then, we can have infinities that are bigger and smaller than each other… the way we are perceiving this is quite paradoxal! Or, at least it appears to us as such.
And be love now, really is a wonderful line of thinking. I fully agree, that it really does not matter, what is the Real Truth or if it exists at all, since all we have is ourselves, right now. If we all focused more on loving and less on all the bad shit, our human realities would definitely improve in multiple ways… but we are flawed beings, so sometimes we can only try… the path towards Good is a difficult one, that I also often struggle with.
That’s to say most people start with a very grounded sense of reality until they encounter something that model can’t deal with such as those epistemological arguments. Science like everything else is built from assumptions, things that seem true but we can’t prove. Stuff like didn’t the past actually happen. It’s typically when one notices reality is stranger than science can manage that one allows themselves to entertain other concepts.
Just a quick quip, it may literally be the case the universe is indeed physically infinite. We don’t know if it is or isn’t. That said, yeah we can indeed create mental constructs that don’t have to obey reality. Linguistically I can create contradictions. I can say on a flat plane there is a square with five sides which is even mathematically impossible yet I can put the words together, create the idea of it. Also yeah Cantor and the scale of infinities is fun. It may be the case we discovered the mathematics for something we’ve yet to discover in reality which happens from time to time.
As they say if it’s worth while it’s probably not easy, if its easy it’s probably not worthwhile. Hate and resentment are easy, forgiveness and peace is difficult. Until one’s enemy is their friend the war is never over. The best war is won without ever taking a single shot. Many things turn into this multivariate balancing act where there really isn’t an ultimate good option, something will have to give here or there, but as you said the intention and the attempt alone are commendable.