Beyond easily verifiable things, like how much toothpaste I have left or how fast objects fall, why should I even bother believing anything? The outside view is that there are people smarter than me that believe every ideology under the Sun, many mutually exclusive, and can effectively and in good faith support their beliefs. I can't possibly agree with them all, and even if I were somehow able to evaluate every argument completely impartially, I doubt I would be able to determine which are true.
I have a worldview, and my beliefs feel real and true from the inside. But this was equally true when I believed in Catholicism and when I believed in the necessity of communism. Since age 17, at any point in my life, I would consider the two-year-prior version of myself cringe and {wrong}pilled. If I look at the path my beliefs have followed, it looks more like a random walk through some high-dimensional political compass than me converging on the truth. How am I supposed to take myself seriously?
The content of most "worldview" type beliefs seems largely irrelevant to my Gnon-given purpose of replication. They're there both to keep my conscious mind invested in an ultimately meaningless existence, and to help me credibly signal allegiance to the proper groups. It feels like I choose what I believe, but it's exactly as illusory as free will, and for the same reason. I know that my subconscious is pulling my strings, rewarding paths of thought that it deems useful and punishing those that risk my social standing. I can feel the flow of dopamine when I fit new evidence to my worldview. I can feel it cut off when I spend too long evaluating the outgroup's beliefs for truth content.
What am I to do? My monkey brain is probably better at winning social games than my analytical mind, so I think I should just stop resisting its guidance with this autistic desire to believe what's actually true. I guess this is giving up on the idea of epistemic rationality, but, like, at least I'm doing it on purpose.