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I think a person has to have an iota of intelligence in order to be afraid and to conquer fear (which IMO is what bravery is). You know those people (some real, some fictional) who earn a Darwin Award by recklessly causing their own deaths? If they'd been even a tiny bit smart, they would've had a sense of danger and at least hesistated before, e.g., bungee jumping at seventy feet using a bunch of taped-together cords. Returning to our story, had the coke dealer possessed the intelligence of a doorstop he would've realized that Batman is the last person in town you should try to deal to. That he didn't realize it doesn't mean he's brave; it just means he's stupid. :-)