|I contend that we are both atheists. I just believe in one fewer god than you do. When you understand why you dismiss all the other possible gods, you will understand why I dismiss yours. -- Stephen Roberts|
I am often asked to explain as a biologist why religion has such a hold. The theory is this: When a child is young, for good Darwinian reasons, it would be valuable if the child believed everything it's told. A child needs to learn a language, it needs to learn the social customs of its people, it needs to learn all sorts of rules -- like don't put your finger in the fire, and don't pick up snakes, and don't eat red berries. There are lots of things that for good survival reasons a child needs to learn.
So it's understandable that Darwinian natural selection would have built into the child's brain the rule of thumb, "Be fantastically gullible; believe everything you're told by your elders and betters."
That's a good rule, and it works. But any rule that says "Believe everything you're told" is automatically going to be vulnerable to parasitization. Computers, for example, are vulnerable to parasitization because they believe all they're told. If you tell them in the right programming language, they'll do it. Computer viruses work by somebody writing a program that says, "Duplicate me and, while you're at it, erase this entire disk."
My point is that the survival mechanism that makes children's brains believe what they're told -- for good reason -- is automatically vulnerable to parasitic codes such as "You must believe in the great juju in the sky," or "You must kneel down and face east and pray five times a day." These codes are then passed down through generations. And there's no obvious reason why it should stop.
There's an additional factor in the virus theory, which is that those viruses that are good at surviving will be the ones that are more likely to survive. So, if the virus says, "If you don't believe in this you will go to hell when you die," that's a pretty potent threat, especially to a child. Or, if it says, "When you become a little bit older you will meet people who will tell you the opposite of this, and they will have remarkably plausible arguments and they'll have lots of what they'll call evidence on their side and you'll be really tempted to believe it, but the more tempted you are, the more that's just Satan getting at you." This is exactly what many creationists in this country have been primed with.