Sorry, I meant that by definition — that’s just a simplified definition of “belief”, what’s true (what’s real) and what’s not. That’s just the standard definition of “belief”, it can be supernatural or natural or mundane or axiomatic or whatever, belief is just a belief.

Knowledge is not self justifying, belief is required. You can’t have knowledge of something that you don’t believe in, what Aristotle defined as “justified true belief”.

Psychologically, the source of what you think of as knowledge is effectively your god, that is, the first principle (or the God archetype if you’re into Jung). For naturalists this is reason and empiricism — but there’s a reason (pun intended) that naturalists only exist in Christian cultures.

For some simple examples, there is no natural explanations for truth, goodness, beauty, or even numbers nor mathematics — we refer to these as transcendent categories. They’re real, and we can have knowledge about them, but only with Christian presuppositions about knowledge, outside of a Christian epistemology it’s all just word games (as postmodernists are want to point out). Our cultural bias is so thoroughly shaped by these Christian presuppositions we don’t even see it, like water to a fish, we just act like these things are obvious (but there’s a reason this only emerges through Christendom)