Edward de Bono Quote

The rejection process is incorporated in the concept of the negative. The negative is a judgement device. It is the means whereby one rejects certain arrangements of information. The negative is used to carry out judgement and to indicate rejection. The concept of the negative is crystallized into a definite language tool. This language tool consists of the words no and not. Once one learns the function and use of these words one has learned how to use logical thinking. The whole concept of logical thinking is concentrated in the use of this language tool. Logic could be said to be the management of NO.

p. 159. - Lateral Thinking : Creativity Step by Step (1970)