Special Pleading and Evolutionary Reasons To Hold A Lousy Argument
The argument against faith goes something like this:
If you support an assertion on the grounds that it is your "faith", then you are admitting that you have no evidence to support it. After all, with evidence to back it up, "faith" would be unnecessary.
However, this means that your claim can be treated as we would treat any claim that was put forwards without evidence. It can be dismissed until evidence is forthcoming.
However, I'd argue that "faith" is simply an after-the-fact justification, a wall to protect an assertion from rigorous public scrutiny after we've somehow picked up that assertion. The interesting point is the special pleading aspect behind this. It's not just an assertion you are attacking - it's their assertion. The arguments for a religion by its apologists are one big example of special pleading, since in other respects the practitioners would follow evidence-based reasoning to the letter. This was also the point behind Dawkins' comment: "Show me a cultural relativist at 30,000 feet, and I'll show you a hypocrite".
My question is why is this special pleading so powerful? Why do we take our views so personally, invest so much emotion in them, and not treat them as facts to be falsified? In other words, why do we fail at persuading others, and why are emotions so powerful? What evolutionary purpose does it serve to break away from strict logical thinking under certain conditions?
And I'm not asking for a glib answer or a witty critique of religious views. I just want to know why we have psychologies that make persuasion such a hit-and-miss affair in general. What psychological facts, evolutionary principles, neurological bases, or social game theory models are there to account for the gullibility or stubbornness of individuals?
The only culprit I can identify so far is a kind of social selection that is an extension of sexual selection, but it doesn't seem to be enough.