epistemology: the theory of knowledge, esp. with regard to its methods, validity, and scope. Epistemology is the investigation of what distinguishes justified belief from opinion.
As with all of the words that end up in this blog category, “epistemology” is a perfectly appropriate word to use…in extremely rare situations. And one of those situations is not when trying to prove to readers that you are hip to the postmodernist jive-talk just like they are, so, hey, will you cool kids let me hang out with you? Puhleeze? I promise I can be aloof, obtuse, and irrelevant!
Seriously. If you’re talking about someone’s view of the world, just use “world view.” It gets to the point and doesn’t have any of the I’m-smarter-than-you-and-I-don’t-think-truth-exists connotations that come along with “epistemology.”