One of the most important weapons in the armoury of the lateral thinker is another invention of Edward de Bono’s – PO.
Challenge is of the essence of lateral thought, and the meaningless word PO is a meaningful way of challenging a statement or idea. Edward’s seminal book on lateral thinking contains the following very useful guide to the grammatical use of PO.
1) PO as interjection. Here the PO would be used by itself as a reply or even as an interruption much as NO is used. It would imply that a particular way of looking at things was being challenged. e.g. ‘The purpose of sport is to encourage that competitive spirit and the will to win’. ‘PO!’