If you see double brackets ((  )), it my comment.

* " There's a saying that all roads lead to Ankh-Morpork, greatest of Discworld cities... And
     It's wrong. All roads lead AWAY from Ankh-Morpork, but sometimes people just walk
     along them the wrong way. "

* " `We should send him up,` said the Archchancellor firmly.
     `Down, Master,` said the Bursar. `Sending him up would mean making spiteful and
      satirical comments about him.`
     `Yes. Good thinkin'. Let's do that,` said the Archchancellor.
     `No, Master,` said the Bursar patiently. `HE is sending US up, so WE send HIM down.`
     `Right. Balance things up,` said the Archchancellor.
     The Bursar rolled his eyes. `Or down,` the Archchancellor. "

* " When he'd been small, people had said things like, `And what do YOU want to be, little
     man?` and he'd said, `I don't know. What have you got?` "

* " ... For quite a long while he'd tried wanting to be a blacksmith, because that looked
     interresting and romantic. But it also involved hard work and intracable bits of metal. Then
     he'd tried wanting to be an assassin, which looked dashing and romantic. But it also
     involved hard work and, when you got right down to it, occasionally having to kill
     someone. Then he'd tried wanting to be an actor, which looked dramatic and romantic,
     but it had involved dusty tights, cramped lodgings and, to his amazement, hard work. "

* " It was widely believed that, if Detritus ((a troll)) could be taught to read and write
     sufficiently to sit down and do an intelligence test, he'd prove to be slightly less intelligent
     than the chair. "

* " Most people think in curves and zig-zags. For example, they start from a thought like: I
     wonder how I can become very rich, and then proceed along an uncertain course which
     includes thoughts like: I wonder what's for supper, and: I wonder who I know can lend
     me five dollers?
     Whereas Throat ((someone's nick-name)) was one of those people who could identify the
     thought at the other end of the process, in this case I am now very rich, draw a line between
     the two, and then think his way along it, slowly and patiently, until he got to the other
     end. "

* " ... Then she handed him a curved sword.
     `Why's it bent?` he asked.
     `I think it's meant to be, dear,` she said doubtfully.
     `I thought swords had to be straight,` said Victor ...
     ... `Perhaps they start oyut straight and go bendy with use,` said the old lady, patting him
     on the hand. `A lot of things do`. "