The theory has its antecedents; in Robert Tressell's 1914 novel The Ragged-Trousered Philanthropists, protagonist Frank Owen directly refers to clothes and boots as necessities where the total cost over time is greater for the working classes, as "[they] can seldom or never afford to buy good things" and therefore must "buy cheap rubbish, which is dear at any price".[2] Likewise, in a 1954 column for The Observer, humourist Paul Jennings made similar comments about boots,[3] and the adage "buy cheap, buy twice" has reportedly sustained itself as a Northern English adage.[4] It has thus been theorized that Pratchett drew inspiration from these antecedents.[5]