Edward de Bono (born 19 May 1933) is a Maltesephysician, author, inventor and consultant. He is best known because he invented the term lateral thinking (structured creativity). He is also very much in favour to explicitly teach thinking in schools.
Most of de Bono's writings are about using lateral thinking to solve problems. In his book Po: Beyond Yes and No (1973), de Bono describes what he calls an "open block". This is when people ignore certain things that may solve a problem, because they already have an idea of how the problem should be solved. They may therefore not recognise other solutions to the problem. For example, if a person's car breaks down, the open block of being used to being in a car may cause them to wait for a taxi, ignoring buses passing by, without even reading the destinations.
In this book de Bono suggested a number of techniques for overcoming the open block. This includes going back and challenging assumptions, or generating new ideas for addressing problems. De Bono calls this a "po". A po is an idea that moves thinking forward to a new place from where new ideas or solutions may be found. Po can be taken to mean any of the following: provoking operation, provocative operation or provocation operation.