“It is well known that any drive to reduce paperwork only results in extra paperwork”

“So much paperwork to read! So much paperwork to push away! So much paperwork to pretend he hadn't received and that might have been eaten by gargoyles.”

“...it is well known that a vital ingredient of success is not knowing that what you're attempting can't be done.”

“Ninety percent of most magic merely consists of knowing one extra fact.”

“As the message drained away Vimes stared at the opposite wall, in which the door now opened, after a cursory knock, to reveal the steward bearing that which is guaranteed to frighten away all nightmares, to wit, a cup of hot tea.** The sound of the gentle rattle of china cup on china saucer drives away all demons, a little-known fact.”

“It's amazing how good governments are, given their track records in almost every other field, at hushing up things like alien encounters. One reason may be that the aliens themselves are too embarrassed to talk about it. It's not known why most of the space-going races of the universe want to undertake rummaging in Earthling underwear as a prelude to formal contact. But representatives of several hundred races have taken to hanging out, unsuspected by one another, in rural corners of the planet and, as a result of this, keep on abducting other would-be abductees. Some have been in fact abducted while waiting to carry out an abduction on a couple of aliens trying to abduct the aliens who were, as a result of misunderstood instructions, trying to form cattle into circles and mutilate crops. The planet Earth is now banned to all alien races until they can compare notes and find out how many, if any, real humans they have actually got. It is gloomily suspected that there is only one - who is big, hairy, and has very large feet. The truth may be out there, but the lies are inside your head.”

“She'd become a governess. It was one of the few jobs a known lady could do.And she'd taken to it well. She'd sworn that if she did indeed ever findherself dancing on rooftops with chimney sweeps she'd beat herself to death with her own umbrella.”