Earlier quoted context omitted.
Most of what you you say is credible. But it comes down to a personal choice about the balance of probabilities for where objective knowledge really resides. I do not trust myself, as one flawed, idiosyncratic and individual brain. I am more likely to trust the established objective view of other consciousnesses. The scientific method is (should be) a collective network of communicating, iterating, self-correcting co…
Still, even in your case if you slowly strip down the layers of your analysis, you will notice that it necessarily boils down to few things that you know directly and you can't build a proof for them because any other proof will be build on them being correct. Look, there are things that you know are correct and you can't make a proof for them (even the "I think therefore I am" is a circular reasoning, the real info…
I don't trust myself here and now, I could be drunk or deluded, or vain, or biased, or self-obsessed (most people seem to be that way).
I don't trust my doctors, they could be under-educated, or self-interested to overtreat me, or publish more papers on anti-doctor paranoia, and self-obsessed (most people are that way).
I only trust some averaged, collective, rational, longer-term, reflective, investigative, independent, reviewed, challenged, criticized and doubted process to get closer to truth.