You know what? I hear a lot about human intelligence, or rather, human stupidity. My current nutshelled theory on it is "Even when one is smart, one can be dumb." What this implies is that human intelligence is limited, but stupidity is not. Meaning that no matter how smart you are, you are still vulnerable to failing or screwing up epically. But the overall factor of intelligence seems to lay within whom screws up the least, and makes the smallest intellectual failures.

But another thing I wonder, is human intelligence genetic/inherited? Because if that's true, I think I can point out one thing that might have a factor.. Umongst a lot of my friends, often whom I consider relatively smart, seem to loathe the idea of having offspring. And yet we got a whole bunch of these promiscuous individuals, whom seem to have little intelligence potential, going around shagging and ditching each other to become solo mothers, whom are also of bad stereotypes, raising kids on minimum wage, some singlehandedly having roughly almost 10 kids. But the same can be applied to those who have settled down. There was this one amish family who had like 12 kids, their excuse being that god told them it was a good idea. That's a pretty skewed ratio in regards to the future generation.

Just some thought I picked up off the top of my head. Kudos to you brilliant minds with big families for bringing good into the gene pool. :P