The de Bono Hats system (also known as "Six Hats" or "Six Thinking Hats") is a thinking tool for group discussion and individual thinking. Combined with the idea of parallel thinking which is associated with it, it provides a means for groups to think together more effectively, and a means to plan thinking processes in a detailed and cohesive way. The method is attributed to Dr. Edward de Bono and is the subject of his book, Six Thinking Hats.

The premise of the method is that the human brain thinks in a number of distinct ways which can be identified, deliberately accessed and hence planned for use in a structured way allowing one to develop strategies for thinking about particular issues. Dr de Bono identifies five distinct states in which the brain can be "sensitised". In each of these states the brain will identify and bring into conscious thought certain aspects of issues being considered (e.g. gut instinct, pessimistic judgement, neutral facts).

Perhaps the most compelling example presented is the idea of sensitivity to "mismatch" stimuli as a particularly strong tendency. This is presented as being a valuable survival instinct - because in the natural world the thing that is out of the ordinary may well be dangerous. This is identified as the root of negative judgement and critical thinking.

Six distinct states are identified

• Neutrality (White) - considering purely what information is available, what are the facts?
• Feeling (Red) - instinctive gut reaction or statements of emotional feeling (but not any justification)
• Negative judgement (Black) - logic applied to identifying flaws or barriers, seeking mismatch
• Positive Judgement (Yellow) - logic applied to identifying benefits, seeking harmony
• Creative thinking (Green) - statements of provocation and investigation, seeing where a thought goes
• Process control (Blue) - thinking about thinking

In order to make it easier to clearly identify and work with these states the use of coloured hats as metaphors for them is used; each state is symbolised by the act of putting on a colored hat, either actually or imaginatively. The use of these metaphors also allows more complete and elaborate definition of the states thus getting past the preconceptions inherent in using people's current language. All of these thinking hats help for thinking deeper for a better learning. Furthermore Dr de Bono asserts that these states are associated with distinct chemical states of the brain - although no details or evidence of this are presented.

In ordinary, unstructured thinking this process is unfocussed; the thinker leaps from critical thinking to neutrality to optimism and so on without structure or strategy. The Six Thinking Hats process attempts to introduce parallel thinking.

Many individuals are used to this and develop their own habits unconsciously. Sometimes these are effective, other times not. What is certain is that when thinking in a group these individual strategies will not tend to converge. As a result, discussion will tend not to converge. Due to the power of the ego and the identified predilection to black hat thinking in the majority of western culture, this can lead to very destructive meetings. Even with good courtesy and clear shared objectives in any collaborative thinking activity there is a natural tendency for "spaghetti thinking" where one person is thinking about the benefits while another considers the facts and so on. The hats allow this to be avoided so that everyone together considers the problems, or the benefits, or the facts, reducing distractions and supporting cross pollination of thought. This is achieved because everyone will put on e.g. the white hat together, then they will all put on the next hat together. In this way all present think in the same way at the same time. The only exception being the facilitator who will tend to keep the blue hat on all the time to make sure things progress effectively. The blue hat tends to be the outward-looking, leader/trail blazing hat that attracts the leaders of all groups.

Having identified the six states that can be accessed, distinct programs can be created, these are sequences of hats which encompass and structure the thinking process toward a distinct goal. A number of these are included in the materials provided to support the franchised training of the six hats method, however it is often necessary to adapt them to suit an individual purpose. Also, programs are often "emergent" which is to say that the group might plan the first few hats then the facilitator will see what seems to be the right way to go.

Sequences always begin and end with a blue hat; the group agrees together how they will think, then they do the thinking, then they evaluate the outcomes of that thinking and what they should do next. Sequences (and indeed hats) may be used by individuals working alone or in groups.

TYPE OF HAT

• White Hat:
  With this thinking hat, you focus on the data available. Look at the information you have, and see what you can learn from it. Look for gaps in your knowledge, and either try to fill them or take account of them.
  
  This is where you analyze past trends, and try to extrapolate from historical data.

• Red Hat:
  Wearing the red hat, you look at the decision using intuition, gut reaction, and emotion. Also try to think how other people will react emotionally, and try to understand the intuitive responses of people who do not fully know your reasoning.

• Black Hat:
  When using black hat thinking, look at things pessimistically, cautiously and defensively. Try to see why ideas and approaches might not work. This is important because it highlights the weak points in a plan or course of action. It allows you to eliminate them, alter your approach, or prepare contingency plans to counter problems that arise.

  Black Hat thinking helps to make your plans tougher and more resilient. It can also help you to spot fatal flaws and risks before you embark on a course of action. Black Hat thinking is one of the real benefits of this technique, as many successful people get so used to thinking positively that often they cannot see problems in advance, leaving them under-prepared for difficulties.

• Yellow Hat:
  The yellow hat helps you to think positively. It is the optimistic viewpoint that helps you to see all the benefits of the decision and the value in it, and spot the opportunities that arise from it. Yellow Hat thinking helps you to keep going when everything looks gloomy and difficult.

• Green Hat:
  The Green Hat stands for creativity. This is where you can develop creative solutions to a problem. It is a freewheeling way of thinking, in which there is little criticism of ideas. A whole range of creativity tools can help you here.

• Blue Hat:
  The Blue Hat stands for process control. This is the hat worn by people chairing meetings. When running into difficulties because ideas are running dry, they may direct activity into Green Hat thinking. When contingency plans are needed, they will ask for Black Hat thinking, and so on.

Problem Solving: When something creates a problem, the performance or the status quo of the situation drops. Problem solving deals with finding out what caused the problem and then figuring out ways to fix the problem. The objective is to get the situation to where it should be.

For example, a production line has an established run rate of 1000 books per hour. Suddenly, the run rate drops to 839 books per hour. Ideas as to why this happened and solutions to repair the production line must be thought of.

Creative Problem Solving: Using creativity, one must solve a problem in an indirect and unconventional manner.

For example, if a production line produced 1000 books per hour, creative problem solving could find ways to produce more books per hour, use the production line, or reduce the cost to run the production line.

Creative Problem Identification: Many of the greatest non-technological innovations are identified while realizing an improved process or design in everyday objects and tasks either by accidental chance or by studying and documenting real world experience.