He'd noticed that sex bore some resemblance to cookery: it fascinated people, they sometimes bought books full of complicated recipes and interesting pictures, and sometimes when they were really hungry they created vast banquets in their imagination - but at the end of the day they'd settle quite happily for egg and chips. If it was well done and maybe had a slice of tomato.

You're allowed to grant people into the darkness, but you must allow them to come out again.

That's a nice song,' said young Sam, and Vimes remembered that he was hearing it for the first time. It's an old soldiers' song,' he said. Really, sarge? But it's about angels.' Yes, thought Vimes, and it's amazing what bits those angels cause to rise up as the song progresses. It's a real soldiers' song: sentimental, with dirty bits. As I recall, they used to sing it after battles,’ he said. 'I've seen old men cry when they sing it,’ he added. Why? It sounds cheerful.' They were remembering who they were not singing it with, thought Vimes. You'll learn. I know you will.

The truth is that even big collections of ordinary books distort space, as can readily be proved by anyone who has been around a really old-fashioned secondhand bookshop, one that looks as though they were designed by M. Escher on a bad day and has more stairways than storeys and those rows of shelves which end in little doors that are surely too small for a full-sized human to enter. The relevant equation is: Knowledge = power = energy = matter = mass; a good bookshop is just a genteel Black Hole that knows how to read.

Heaven has no taste." "Now-" "And not one single sushi restaurant." A look of pain crossed the angel's suddenly very serious face.

There are some things that are more appropriate to a children's than an adult book but there's a huge overlapping area and most kids read an age group up anyway.

Who'd want a pony when you could have the whole universe? It was far more interesting and you didn't have to muck it out once a week.