Carrying on with responses to your "Twenty good arguments for Christianity". First 10 responses can be found here: http://tl.gd/kqk887
11. This is a variation on the fine-tuning argument. We only have one universe to study so, for all we know, EVERY possible universe must turn out like this.
Have you considered that the reason why we find this universe rational is because our minds arose in this universe?
12. Hard to explain? Maybe. Impossible to explain from a materialistic point of view? Certainly not. Humans are social creatures, we have emotions that help tie us together in social groupings, combine this with self awareness and the ability to project ourselves into the future and you have all those things you mentioned. These things are a byproduct of higher brain function and provided our ancestors with an advantage.
13. Nope. At worst, Christianity explains a mystery with another mystery, god, at best it is a series of 'just so' stories cobbled together to provide an 'explanation'.
How is: Two men, Coolum and Ninderry, were fighting over a woman named Maroochy. In a climactic battle Ninderry knocked Coolum’s head from his shoulders into the sea to lie where it is today as Mudjimba Island.
Any different to: Women experience pain during child birth because the first woman, Eve, tricked by a talking snake into eating the forbidden fruit, was cursed by god
14. This is another Argument ad populum. Lots of people believing there's a 'spiritual reality beyond the material world' doesn't make it so. Was the world actually flat back when people thought that was the case? No, the majority of people were mistaken.
15. Universal morals, even though I'd argue there's a very small set of morals that are truly universal (even then, psychopaths don't adhere to most of those so it's not truly universal) can be explained without the need for god. Again I ask, why invoke god when a perfectly mundane explanation will suffice (you alluded to it in your post)? Namely, humans are social creatures and societies that don't adhere to certain moral values don't stick around for long. Combine this with the fact that there is a learned aspect to your morals as you grow up in a society and you see how it can be done.
16. No doubt, fervent belief can be a powerful motivator. Doesn't make the thing you're believing in true.
17. Except that this god waited until the 1800s to end slavery instead of doing it before christianity existed (See Leviticus 25:44-46). Why couldn't he make it the 11 commandments and slip a no-slavery clause in there? Why did he hand down rules on who you could enslave, how long you could enslave, how to mark your slaves as yours and how close to death you could beat a slave without being punished then wait over 2000 years to 'enlighten' some wealthy westerners to the truth about slavery?? A very poor argument indeed.
18. They also destroyed cultures, spread disease, wiped out languages etc etc Some good people did some good things, no proof of god here.
19. Speculation. I guess you could get all of that out of David and Revelation, if you squint really hard. The Antichrist is described as a Beast rising out of the sea having seven heads and ten horns. I think we'd recognise the Antichrist if we saw him.
20. Doesn't sound very phenomenal to me, surely we could say the same thing about the Greeks, Romans, Britons and Gauls, Persians, Mesopotamians and Egyptians or the Chinese? They're all still with us today and have all had an impact and influence on the world.
Well, glad that's over, starting to fade...