Karen

“In fact he was incurably insane and hallucinated more or less continuously, but by a remarkable stroke of lateral thinking his fellow wizards had reasoned that, in that case, the whole business could be sorted out if only they could find a formula that caused him to hallucinate that he was completely sane.*

*This is a very common hallucination, shared by most people.”
― Terry Pratchett, The Truth: Stage Adaptation

“It wasn't by eliminating the impossible that you got at the truth, however improbable; it was by the much harder process of eliminating the possibilities. You worked away, patiently asking questions and looking hard at things. You walked and talked, and in your heart you just hoped like hell that some bugger's nerve'd crack and he'd give himself up.”
― Terry Pratchett, Feet of Clay

“...but William felt in his bones that you couldn't run a city on the basis of what the Watch liked. The Watch would probably like it if everyone spent their time indoors, with their hands on the table where people could see them.”
― Terry Pratchett, The Truth: Stage Adaptation

“Have - have you got an appointment?' he said.
'I don't know,' said Carrot. 'Have we got an appointment?'
'I've got an iron ball with spikes on,' Nobby volunteered.
'That's a morningstar, Nobby.'
'Is it?'
'Yes,' said Carrot. 'An appointment is an engagement to see someone, while a morningstar is a large lump of metal used for viciously crushing skulls. It is important not to confuse the two, isn't it, Mr-?' He raised his eyebrows.
'Boffo, sir. But-'
'So if you could perhaps run along and tell Dr Whiteface we're here with an iron ball with spi- What am I saying? I mean, without an appointment to see him? Please? Thank you.”
― Terry Pratchett, Men at Arms