http://www.theguardian.com/books/2014/sep/24/terry-pratchett-angry-not-jolly-neil-gaiman
I want to tell you about my friend Terry Pratchett, and it’s not easy. I’m going to tell you something you may not know. Some people have encountered an affable man with a beard and a hat. They believe they have met Sir Terry Pratchett. They have not.
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Beneath any jollity there is a foundation of fury. Terry Pratchett is not one to go gentle into any night, good or otherwise