I don't think we disagree. A hypothesis is upgraded to "belief" and therefore to the "spectrum of truth" only because it's the best you know of, not because it's the only one. It's a matter of degree, not kind. And a belief's position as the best one is always precarious; it can be unseated at any time by a better hypothesis.
Axioms are different, but over time I've found that even those weaken and become "merely" strong beliefs (or, more usually, only True within the context you're working in, e.g. mathematics). Even "I think therefore I am" is not axiomatic, I have come to believe. In fact I doubt it's important to identify some sort of root cause, which is rationalist heresy. Oh well.