I suppose this will come back around again to our old dispute of whether morality and ethics comes from within or without - if it comes from...elsewhere, then listening to that innate sense is entirely appropriate. If not, then that innate sense is nothing more that reason and experience again, I think
It may or may not be nothing more than reason and experience, but even if it is limited to that, the innate sense can still be valid even if the person sensing it isn't able to give all the reasons for why it's so. Yeah, that involves a risk that it could be coming from some evil demon instead, but that's where that ol' leap of faith comes in.