Link: Appeals to evidence may decrease donations among donors primarily seeking warm fuzzies: http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2421943 hat tip http://marginalrevolution.com/marginalrevolution/2014/04/does-greater-charitable-effectiveness-spur-more-donations.html
My understanding, you might believe in some continued life after death, something about human souls, any sort of supernatural things, but not believe in a personified interacting deity who gave humans orders like worship me, do this/that etc., nor be a deist who thinks there is such a being but doesn't give orders for some reason.
Wait, what? This might be a little off topic, but if you assert that they lack evidence and are drawing conclusions based on motivated reasoning, that seems highly relevant and not ad hominem. I guess it could be unnecessary, as you might try to focus exactly on their evidence, but it would seem reasonable to look at the evidence they present, and say "this is consistent with motivated reasoning, for example you describe many things that would happen by chance but nothing similar contradictory, so there seems to be some confirmation bias" etc.
Fighting has a huge signalling component: when viewed in isolation, a fight might be trivially, obviously, a net negative for both participants. However, either or both! participants might in the future win more concessions for their willingness to fight alone than the loss of the fight. As humans are adaption executers, a certain willingness to fight, to seek revenge, etc. is pretty common. At least, this seems to be the dominant theory and sensible to me.
Take the leadership feat, and hope your GM is lazy enough to let you level them. More practically, is it a skills problem or as I would guess an agency problem? Can impress on them the importance of acting vs not? Lend them the Power of Accountability? 7 habits of highly effective people? Can you compliment them every time they show initiative? etc. I think the solution is too specific to individuals for general advice, nor do I know a general advice book beyond those in the same theme as those mentioned.
Like: Houston though