Thinking occurs in two stages

Preception
Processing

Traditionally we have only concerned with PROCESSING, PERCEPTION is believed to be obvios.
PERCEPTION was never regarded as thinking because
  1. The obvious way is the best
  2. Yes/no needs something before it can work
Example of CLOCK
SHEEP

PO system + lateral thinking

In yes/no system you must be right of each step but in to being right is not important
In Yes/no system you only copnsider, what is related to the situation. In PO system you can bring in Random material from outside.
PO is need to protect an idea from Yes/no judgements. So it can act as a stepping store to Yes/no ideas.
Po can challenge Yes/no judgements and classifications.
PO can be used as bypass to ask for different ways of looking at things without having reject the current idea first.