Terry Pratchett Quotes
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.
Pratchett, Terry. Guards! Guards!. Victor Gollancz, 1989.
Sir Terence David John Pratchett OBE was an English humorist, satirist, and author of fantasy novels, especially comical works. He is best known for his Discworld series of 41 novels.