The fact was that, as droves of demon kings had noticed, there was a limit to what you could do to a soul… — Terry Pratchett
The fact was that, as droves of demon kings had noticed, there was a limit to what you could do to a soul with, e. g., red-hot tweezers, because even fairly evil and corrupt souls were bright enough to realize that since they didn't have the concomitant body and nerve endings attached to them there was no real reason, other than force of habit, why they should suffer excruciating agony. So they didn't. Demons went on doing it anyway, because numb and mindless stupidity is part of what being a demon is all about, but since no one was suffering they didn't enjoy it much either and the whole thing was pointless. Centuries and centuries of pointlessness. (p. 163)
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More from this book
"This is really horrible," said Eric, as they walked away. "It gives evil a bad name." (p. 171)
The kings of Hell might have heard of words like "subtlety" and "discretion," but they had also heard that if you had it you should flaunt it and reasoned that, if you didn't have it, you should flaunt it even more, and what they didn't have was good taste. (pp. 186-187)
The speaker was Duke Vassenego, one of the oldest demons. How old, no one knew. But if he didn't actually invent original sin, at least he made one of the first copies. In terms of sheer enterprise and deviousness of mind he might even have passed for human and, in fact, generally took the form of an old, rather sad lawyer with an eagle somewhere in his ancestry. (pp. 173-174)

