Source, in full
Attributed to Chesterfield by George Agar-Ellis, 1st Baron Dover, in his 1833 edition of Horace Walpole's letters to Sir Horace Mann, similar statements have been attributed to many others, such as Lord Chief Justice Campbell, William Henry Maule (in the form "You silly old fool, you don't even know the alphabet of your own silly old business"), Sir William Harcourt, Lord Pembroke, Lord Westbury, and to an anonymous judge, and said to have been spoken in court to Garter King at Arms, Rouge Dragon Pursuivant, or some other high-ranking herald, who had confused a "bend" with a "bar" or had demanded fees to which he was not entitled. George Bernard Shaw uses it in Pygmalion (1912) in the form, "The silly people dont [sic] know their own silly business." Similar remarks occur in Charles Jenner's The Placid Man: Or, The Memoirs of Sir Charles Beville (1770): "Sir Harry Clayton ... was perhaps far better qualified to have written a Peerage of England than Garter King at Arms, or Rouge Dragon