In a 1999 interview, Pratchett commented upon the phrase: "I "like" the lies-to-children motif, because it underlies the way we run our society and resonates nicely with Discworld." He was critical of problems inherent in early education: "You arrive with your sparkling A-levels all agleam, and the first job of the tutors is to reveal that what you thought was true is only true for a given value of 'truth'." Pratchett cautioned: "Most of us need just 'enough' knowledge of the sciences, and it's delivered to us in metaphors and analogies that bite us in the bum if we think they're the same as the truth."