@tangs btw - are you a mathematician? I am trying to get my head around 'Gödel's Incompleteness Theorems' atm - but realise I need years of training - and yes 'theorems = plural' - would have thought one is enough I tried to read a book by one Hofstädter years ago, which explained them, but gave up after page 50. (it was called 'Gödel Escher Bach'). re thread; interesting times ahead! Taurisk