[rendall]

I suppose that I think of holding values and knowing facts to be non-overlapping magisteria (qv Gould). In a reasonable person, facts will inform values, but values don't need to be (and cannot always be) justified by facts. You and I may have the exactly the same set of facts and nevertheless draw different conclusions.

Belief in something as a fact, however, does need to be justified by evidence; especially where used to support values.

>> isn't even the scientific method at its core also based on certain beliefs about the world for which there is no empirical basis?

That's a good point. What do we accept as true, a priori, if we only believe that for which there is evidence? After all, while there is a philosophical basis for you to know that you exist, there is no philosophical basis for you to know as a fact that anything else besides you exists. It is a conundrum.

Still, I think we can still acknowledge uncertainty in our beliefs. "I will act in the belief that X is true even though I have incomplete certainty, but will update my behavior and beliefs given new evidence."