Confirmation that Enigma is the name of the theme is provided by Elgar's 1911 programme note ("... Enigma, for so the theme is called") and in a letter to Jaeger dated 30 June 1899 he associates this name specifically with what he calls the "principal motive" – the G minor theme heard in the work's opening bars, which (perhaps significantly) is terminated by a double bar. Whatever the nature of the attendant puzzle, it is likely to be closely connected with this "Enigma theme".