But at some point we rely on postulates, things that are so in consonant with our experience, generalizations from our experience, or things we learned from reliable sources that we don’t require proving. Even in a proof, there is where we begin our proof.
The deeper faith is one in which the principles of Judaism are postulates, not theorems that require proving. If we can, after the fact, gain greater appreciation for them through proof, or understand their implications, connotations are less fundamental details by giving them philosophical treatment, great.
This is what I meant when I wrote that while there is an obligation to engage in machashavah amuqah, emunah itself is a middah — an attitude, not the product of that deliberation.
Just as we rely on information from our senses and generalizations from them to produce postulates about which we reason, we can also rely on mental experience. Einstein’s heavy use of thought-experiments is one example. So is our acceptance of Euclid’s posulate about parallel lines — despite the impossibility of parallel lines of infinite length ever really existing.
Yes, people convince themselves that they had experiences they did not. They can confuse the line between the experience itself and their judgement of it (liking or disliking it, etc…) This is true of mental experiences as well as sensory impressions. We color our memories, often quite profoundly, but we don’t go through life questioning conclusions based on what we recall. Simply, we trust ourselves, particularly after repeated experience. We develop a fear of falling well before we learn anything formal or rigorous about gravity. Why shouldn’t religion be accepted on the same terms?
Proofs have a role in deepening understanding — after the basic principles have been accepted. This is why the Kuzari has much to say philosophically, as long as one’s belief is not on philosophical foundations.
The rejection of deriving Judaism philosophically is not only Rav Yehudah haLevi’s approach. It’s also a central feature of R’ Chasdai Crescas’s objection to the Rambam in Or Hashem.
A final note about other faith communities and their experiences: It’s not really my problem. I shouldn’t need to be able to validate my experiences in the eyes of others before accepting them myself. After reaching that point, I can use philosophy to try to understand questions like this one. Just as the Kuzari does. After invoking the superiority of tradition over philosophical proof, the rabbi does offer rationals. But only after.