Explain, ac. Enlighten me. In reference to the first 4 paragraphs.
You haven't heard of string theory? Basically, there are 4 main forces in the universe, electromagnetic, gravity, and the strong and weak nuclear forces. There's always been a gap that exists between unifying all the mathematical theories between all these forces. The problem being the smaller down the scale you get, from the large, kepler's laws, einstein's spacetime to the miniscule of quantum level mechanics, nothing it seems can adequately predict the behaviour of the smallest particles, and reconcile it with everything else. To cut a long story short, thanks to the maths of string theory, it seems that there are about 11 dimensions other than the ones we can observe now. So, just because the normal layman can't grasp dimensions larger than 3, doesn't mean that others haven't taken the step to look beyond.
The flatland refer's to cheez's analogy. Taken another way, the coin could be someone with deep religious belief but does not want to see anything other than their own world when faced with a pencil. Also he points out that the possibility of a god is a big IF, one that those who strongly disbelieve would be wise to pay attention to. That's an example of blaise pascal's wager -- it's better to believe that there is a God because you will gain more if you're correct than nothing if there isn't one, and being sent to hell if you're wrong. Personally i don't think anyone should believe out of fear, and those that do for the wrong reasons are worse than those that don't but do good.
homo sittus in cavus butnotto enuf beerus - man who sits in cave but there's not enough beer.
Really though, if i say your granddad is ah meng's brother, how would you feel? It's rather sad, but just like how the church condemned galileo and copernicus with their idea that the earth is not the center of the universe, those against evolution tend to disagree with the notion that chimps (i.e. animals, not humans ) might have a common ancestor with us. It's similar to saying that everyone is an animal, that adam and eve were nothing more than chimps, it undeniably creates doubt in the truthiness of the western religions and usually the word ape is used to show how condescendingly silly evolution is. But in reality, we're not descended from apes at all.
And once again, the ability to feel compassion is built into all of us. It's a still a raging debate on nurture vs nature. But if you take for example meerkats, they look after each other, tend to each other's babies, and why is that? Evolution would suggest that doing so ensures the species survival. And maybe it's the same for us.