I'm not a ''believer'' - I question everything and accept what can be experienced. I don't care for speculation - it leads you nowhere
It's just that, for me, it's like somebody telling me I can't fly, because they haven't seen any planes, while I already know it's possible, because I have flown quite a lot.
It's simply a matter of experience.
I have spent countless hours in meditation (questioning everything), countless more hours listening to Jiddu Krishnamurti, and many more hours reading over the words of R. Maharshi and Sri Nisargadatta Maharaj, so I'm more than familiar with the "mode" of knowledge/ understanding that you speak of, and I do respect this approach....
....and I might be wrong here, maybe I'm just not as "advanced" as you are in the "self-knowledge" approach to know enough to speak at your level of confidence...
...but, I've come to the conclusion that it's all just an ego game in the end, both the knowledge by external observation method and self-knowledge approach, and, because the latter is so "close" to the senses (the "center", or "self"), I feel that it can lead to an over-confident perspective on matters, regarding this question of what is true and what is not.
In meditation I can get very "close" to the "root of my intuition" and become very sensitive to what I can only refer to as the experience of discovering seemingly self-evident facts about the nature of my consciousness, many of which come to me as surprises - I guess most people would call them "insights". All this is good and well, but I still see no proof there. My mind could still be tricking me.
I may go very "deep" and have many insights, but there's no way for me to know how far I've gone compared to how much is there. I'd like to think that I've "reached into my unconscious mind and exposed the full reality of my consciousness", but, for all I know, I might have never even left the relatively small bubble of conscious awareness and still have infinitely further to go to reach the unconscious limits, if they even exist.
There's no sign posts there, no ways to gauge if what's unveiled is a look into my true nature or an elaborate story that's made on the spot (presumably from the creative depths of my own unconscious) which only satisfy my senses in that moment as being true. How to tell?
As I see it, either approach (Western Science or Eastern "Self-Enquiry") requires some level of faith. Science works on the basis that matter is "real", and Self-Enquiry can only operate on the basis that intuition is accurate at discerning the real from the imagined.
Where does an honest "truth-seeker" begin? I suppose it requires faith.
"An honest truth- seeker" begins with questions and doubts - like you, me, and the rest of the bunch :))) I think we all go through a process of trial and error until we find something that works for us and it's also objective.
And again, your description shows you haven't gone too far with your introspection. Had I been you, I would have stuck to tangible proofs as well. (Besides, what works for me doesn't have to work for you - who knows in which way you'll find the answers you seek. Good luck with that!)
Our experiences don't contradict each other, they happen on different levels and are necessary steps in our evolution.
I am truly enjoying our mind encounter, I hope this will happen again sometime :)