The Citadel is an archive of information for George R.R. Martin's A Song of Ice and Fire.
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Another interesting thing from the con, at one point in a panel GRRM was commenting that he didn't like how in a lot of fantasy stories various races are all defined by a single personality (i.e. all orcs are evil, all elves are wise, etc), whereas it would be more realistic for various individuals within a race to have different personalities, viewpoints, etc. Some quick-witted audience member asked him how that idea applied to the Others in his own books, to which he replied, "I'm not gonna answer that." Food for thought.
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