Gödel, Escher, Bach: an Eternal Golden Braid
by Douglas Hofstadter
⇥ The first thing to say about our formal system - the MIU-system - is that it utilizes only three letters of the alphabet: M, I, U. That means that the only strings of the MIU-system are strings which are composed of those three letters. Below are some strings of the MIU-system:⏎ MU⏎ UIM⏎ MUUMUU⏎ UIIUMIUUIMUIIUMIUUIMUIIU🏁