The boundary between philosophy and fiction is not as clear cut as you may think and the two definitely interact..
I don't think there's any great mystery to writing female characters, so long as you talk to them. If you lived in a monastery and never met any women, maybe it would be difficult.
I have quite a few different Bibles. Having rejected my parents' religion, I still think the King James Bible is the most important work of literature in English. None of us can help being influenced by it.
When I'm writing a woman character, I don't think, 'What would a woman do?' I just think, 'What would this character do in this situation?