PDF Summary:Six Thinking Hats, by Edward de Bono
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1-Page PDF Summary of Six Thinking Hats
In Six Thinking Hats, doctor and psychologist Edward de Bono takes the phrase “put your thinking cap on” to a new level. As De Bono explains, our normal thinking process is a hopeless tangle of six different types of thinking. We can improve the quality and efficiency of our decisions by untangling these six thinking types (symbolized by six hats of different colors) and deploying them more consciously.
Six Thinking Hats will teach you how to incorporate factual, emotional, critical, constructive, creative, and metacognitive information into your thinking process, along with strategies you can use to generate ideas in each of these modes. If you’re looking for ways to dramatically cut your decision-making time, calm your inner critic, or increase your team’s creativity, the Six Hats method can help.
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- Facilitators: Guide the granularity of the data you’re targeting through questions. For example, you could say, “Let’s white-hat the economic environment for our product. What do we know?” Then you could narrow this to “Now find me X competitor’s annual report for last year.”
The Red Hat
The red hat is the emotional hat. Red hat thinking is pure emotion. Red is the color of blood, symbolizing strong emotions like passion and anger. Under the red hat, you reflect on exactly how you feel about a person or situation.
The red hat is the opposite of the white hat. The white hat wants pure facts, stripped of emotion and agenda. The red hat wants your emotions, intuitions, and gut feelings about the issue, with no need for supporting evidence or explanations.
Examples of red hat contributions are:
- “This seems like a terrific investment to me. I’m feeling really keen.”
- “I don’t know what it is exactly, but something about this deal smells fishy.”
Red hat data includes emotions, intuitions, and gut feelings. Emotions are necessary for proper thinking, and they play an important role in any decision. In fact, any final decision needs to feel good as well as being intellectually justifiable. Suppressing emotions just makes them pop up again cloaked in rationality. The red hat allows people to express their emotions fully and honestly, without needing any justification or rationalization. Intuitions are quick assessments of a situation that you can make based on significant previous experience. Gut feelings are premonitions you have about the outcome of a situation (for example, “You know, I just can’t see this ending well for anybody.”)
How to Use the Red Hat
- Emotions change fast. It’s possible to refine and modulate even very deep-seated emotions through discussion and over time. Because of this, it’s good practice to return to the red hat several times during a discussion. For example, you might want to do some red hatting at the start to check people’s initial reactions, and some more in relation to potential solutions.
- If there are very strong emotions on a particular issue, consider invoking the red hat early in the discussion to clear the air.
- Under this hat, seek to get to the core of the emotion quickly. Actively discourage explanations and justifications. You can do this by allocating only a very short amount of time, say 30 seconds, per person.
The Black Hat
The black hat is the critiquing hat. Black hat thinking looks for problems and logical flaws. The black hat is focused on survival—it’s the hat that looks out for danger and keeps us alive. Black hat thinking kept our ancestors from being eaten by predators or falling off cliffs. Being sensitized to danger is a crucial part of our neurochemistry and serves a valuable purpose. The black hat considers the questions: “What’s wrong with this picture?”, “What’s the worst possible outcome?”, and “What are the risks?” Specifically, the black hat asks: “Has this type of thing failed before? If so, why?”
Current education systems, especially at post-secondary level, teach and reward critical thinking, so it’s no surprise that many people are experts with the black hat. They excel at finding problems everywhere and pointing out logical flaws. This is useful and important, because black hat thinking keeps us from making irreparable mistakes. But too much of the black hat can stunt our thinking under other hats, especially yellow and green.
The black hat gets misused in two main ways.
- People who are black hat thinkers by default often have great difficulty switching off the criticism when it’s time to work with the other hats. This can mean that new ideas get squashed before they have time to grow, or that a proposal is thrown out entirely rather than examined for its potential strengths.
- Black hat thinking can easily become tied to ego. Using the black hat to feel smarter than others is a common abuse of the black hat. Before making a black hat contribution, stop and ask yourself: “Is this genuinely helpful, or am I just saying it to make myself look good?”
How to Use the Black Hat
- Be as critical as you like. When it’s designated black hat time, rip as many holes in the idea as you can. By criticizing the project now, you’re providing a valuable service: You’re making sure that something flawed doesn’t go out into the world and do damage or lose the company a lot of money. But:
- Practice switching off the criticism immediately when you take off the black hat.
- Remember that black hat contributions are made alongside other contributions—they don’t override them.
- Be vigilant about not letting black hat thinking creep into sections designated for other hats. You may need to call people out directly on this: “Stan, that’s an important thought, but it’s more of a black hat contribution. We’ll get to the black hat in a minute. For now, what neutral information can you give me on this matter?”
- Don’t police people for being “too negative.” Give expert black hat thinkers free rein to do their thing and rip the arguments and proposals on the table to shreds…but only when it’s time for the black hat.
The Yellow Hat
The yellow hat is the constructive hat. Yellow hat thinking is positive and concrete. You can remember this easily: Builders often wear yellow hardhats when working on new buildings, and yellow is the color of sunny optimism. Under the yellow hat, you find ways to be optimistic. You search for value. You ask: “What’s the silver lining?” and “How can I make this work?”
Like black hat data, yellow hat data is based on logic. Under both the black and the yellow hats, you’re considering ideas in light of your and other people’s past experiences. But this time, instead of thinking about everything that’s gone wrong in the past, you’re thinking about what’s worked.
Yellow hat contributions are about improvement. Proposals are classic yellow hat contributions. The yellow hat is concerned with generating proposals, finding sound reasons why proposals are likely to work, and developing strong proposals further.
Simple, obvious suggestions are just as valuable as revolutionary ones. In fact, you may choose to save this type of serious out-of-the-box thinking for the green hat.
How to Use the Yellow Hat
- Because most people have never been trained in yellow hat thinking, it might take a little while to get the hang of it. It may help to think of it as the opposite of black hat thinking: Wherever you see strong points, highlight them. Wherever you see weaknesses, try to build them up instead of tearing them down.
- Consider using the yellow hat directly after the black hat to deliberately strengthen the weaknesses that have been identified by the black hat.
- Yellow hat contributions can be tricky to monitor, as the borders with the red hat (positive emotions) and the green hat (new ideas) can be fuzzy. Don’t be too rigid about policing this line—if a contribution seems to belong elsewhere, just raise the issue of whether it might be better to address later on under another hat.
- It can also be difficult to put your finger on the difference between yellow hat, black hat, and white hat contributions, because written down they can all look very similar. The difference between these three hats is context. Let’s say you’re looking to construct a building in a particular neighborhood. Under the white hat, someone has provided the following information: “Planning regulations in this neighborhood stipulate that all new buildings be below eight stories.” If your goal is to build a skyscraper, this piece of information fits under the black hat: It’s a flaw in the design of your project, and means the project will have to be either reworked or relocated. But if your goal is to build an eight-story building with a gorgeous view from the top, the planning regulation fits under the yellow hat: It’s a sound reason why the project is more likely to succeed.
The Green Hat
The green hat is the creative hat. Green is the color of new growth, and green hat thinking looks for new and original ideas. Though the attitudes that drive green hat and yellow hat thinking are quite similar (a sense of possibility; a desire to build rather than break down), the thinking styles involved are qualitatively different. For example, you might know someone who is very optimistic but quite conventional in their ideas. You might also know someone who is highly creative but not very optimistic. This is why we consider the green hat and the yellow hat separately in practice.
The green hat asks, “How can I look at this problem differently?” and “Where does this new idea take me? When you put on the green hat, you’re coming up with combinations of ideas that, as far as you know, nobody has ever considered before.
Po and the Stone That Jolts the Wheel out of the Rut
Green hat thinking is about jolting yourself out of your normal thinking patterns. Think of a horse-drawn carriage being driven along a dirt track. Though the whole path is available to the carriage, it quickly settles into the ruts left by previous carriages. The wheels will stay in the ruts until they’re jolted out, either through an input of deliberate energy from the driver and horses or by an obstacle such as a stone.
Similarly, thinking will tend to follow normal, well-traveled pathways unless something gets put in the road. A provocation is a mental stone in the rut of normal thinking. A provocation might be something like “People should be paid to have pets” or “A manager’s subordinates should decide whether or not she gets promoted.”
Po, standing for “provocative operation,” is a word you can use to signpost a provocation. The deal is that you’re not allowed to meet a po with a black hat—you have to run with the suggestion. Here are some examples of po:
- Po roads should have a special motorbike lane.
- Po we should get rid of the whole HR department.
How to Use the Green Hat
- While it’s usually not too hard to generate pieces of information and positive and negative analyses, completely new and creative ideas are different beasts. Sometimes, as hard as you try, you simply won’t be able to generate any interesting new ideas. Under the green hat, what matters isn’t the output volume but the time and effort that you’ve put in.
- Dedicate adequate time to the green hat. In contrast to the red hat, in which extra time just tends to muddy the waters, under the green hat time can be the difference between no ideas and excellent ideas.
- Keep the black hat far away. The black hat is poison for undeveloped idea seedlings.
- Don’t gatekeep wacky ideas, even if they seem completely useless. Note them down, and see where they take you.
- Make sure to allocate time to the green hat, even if there’s no pressing problem to solve or pressure to develop a new idea. You never know what might arise.
- Train yourself and others to recognize good ideas when you see them. In many groups that have trouble being creative, the problem isn’t actually a failure to generate good ideas—it’s a failure to recognize and develop good ideas when someone suggests them.
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PDF Summary Introduction
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Today’s schools are good at teaching content. But most fail at something more basic: teaching children how to think. Most children learn thinking skills indirectly, via examples that prioritize debate and argumentation.
Our Western intellectual tradition is essentially dialogic in nature. It dates back to the ancient Greeks (Socrates, Plato, and Aristotle) who codified a thinking style based on debate, questioning, and intellectual combat. Under this tradition, each person presents their ideas as completely as possible, and then another person clarifies and refines them through criticism and argument. We usually experience this dynamic in a confrontational way: If you have an idea, you present it as completely as possible. Then you defend it while other people attack it from different angles. You can think of this as the “marble statue” approach: Start with a complete block of marble and chip away at it until you have what you need.
Because our culture has been steeped in this tradition for thousands of years, it’s invisible. To us it just feels like normal thinking. But what happens when we use a different metaphor to think about thinking? What if the statue is made...
PDF Summary Chapter 1: The Blue Hat
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“Focus” doesn’t mean that the meeting has to have only one goal. There can be multiple focuses, as long as everyone present is clear on what these are. An effective method is to frame the discussion with one broad objective and several more specific sub-objectives. For example, a meeting could have the broad objective of finding ways to increase customer satisfaction. Sub-objectives could be improving the company website and enhancing customer service in-store. The blue hat role manages the interplay among these three objectives, providing both the freedom to generate creative ideas on a general level and the discipline to stay with the sub-objectives long enough to workshop some specific, useful, practical ideas in these areas.
Probing and Targeting Questions
Asking questions is a powerful way to focus attention. Questions often result in more open-ended, independent thinking than directives do. Consider the following instructions:
- Directive: “Put on your green hat and give me some new ideas on this.”
- Open-ended: “Let’s put on our green hats. What happens if… ?”
The second instruction carries a sense of freedom and potential that the first doesn’t. There’s...
PDF Summary Chapter 2: The White Hat
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Accuracy
There are facts you’re completely sure of, facts you’re pretty sure of, and facts that you think might be correct. All of these are admissible under the white hat, as long as you label them correctly.
For simplicity’s sake, let’s classify white hat facts into two categories: Level 1 (certain, independently verified) and Level 2 (needs verification). Feel free to propose as many Level 2 facts as you like. But if you’re going to make a decision based on a Level 2 fact, make sure to verify it and take it to Level 1 first.
Probability
Truth is a philosophical question. It has to do with logic and mathematical proof. For example, if you go through your whole life only seeing orange carrots, you might believe the following statement to be true: “All carrots are orange.” But the moment you see a white or purple carrot, you have to acknowledge that this statement has been false all along.
If you’re thinking only in terms of black-and-white logic, you have to throw out the “All carrots are orange” statement completely. But Six Hats deals with practical thinking, not mathematical logic. If we waited to be absolutely sure in logical terms, we’d be...
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Learn more about our summaries →PDF Summary Chapter 3: The Red Hat
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Intuitions
The word “intuition” can be misleading, as we use it to refer to two different things:
- A flash of inspiration. This might completely change your perception of a problem you’re working on, or offer a solution that was right in front of your eyes the whole time.
- A quick assessment of a situation based on significant previous experience.
Red hat intuition is the second type: What do you feel about this situation, if you look at it through the lens of your accumulated previous experiences? The first type of intuition belongs under the green hat, where you’re looking at established mental patterns and figuring out how to break them.
Gut Feelings
Gut feelings are premonitions you have about the outcome of a situation (for example, “You know, I just can’t see this ending well for anybody.”) Some gut feelings have obvious explanations, while others are more mysterious.
Most people aren’t very good at working with gut feelings. They either let the feeling determine the decision, using one-sided white hat information and either yellow or black hat analysis to support the feeling, or they repress the gut feeling and attempt to proceed using logic...
PDF Summary Chapter 4: The Black Hat
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Black Hat Questions
While you’re wearing the black hat, consider these questions:
- What’s wrong with this picture?
- What are the flaws?
- What might go wrong?
- What happens if… (negative event)?
- What happened in the past when people tried to do this?
- What do we risk by taking this course of action?
- What’s the worst possible outcome?
Black Hat Data
Black hat data includes drawbacks, obstacles, design problems, deficiencies, and weak points. It’s important to note that black hat thinking draws significantly on the past: It considers past experiences and uses this to make logical projections into the future. When wearing the black hat, you’re asking, “Has this type of thing failed before? If so, why?”
Most black hat thinking revolves around the word “but”:
- “That marketing plan sounds okay, but I’m not sure it fits the current retail environment.”
- “Earlier bedtimes for the kids are a great idea. But it’ll be tough to get them on board.”
Key Black Hat Concepts
Logical Flaws vs. Practical Obstacles
Black hat thinking is useful for identifying two types of problems:
- Logical flaws in an argument
- Potential...
PDF Summary Chapter 5: The Yellow Hat
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Key Yellow Hat Concepts
Yellow Hat Thinking vs. Blind Optimism
Yellow hat thinking is positive and optimistic, but ideally it’s also grounded in evidence and logic. “Don’t worry, even though things look bleak, everything’s going to be all right” isn’t genuine yellow hat thinking—it’s blind optimism.
In practice, the dividing line between blind optimism and a tiny but exciting possibility can be difficult to see. There are examples everywhere of people who started new ventures based on improbable dreams and succeeded. So how can you tell what’s viable yellow hat thinking and what isn’t? The answer is to think about the next step. If your plan requires a great deal of luck to work (for example, happening to get the attention and interest of a large investor), it’s a pipe dream. Set it aside. However, if you can see a clear path forward that’s mostly composed of your own efforts, the proposal is worth developing further.
To manage yellow hat probabilities intelligently, consider using a probability spectrum:
- Definite
- Very likely
- 50-50
- Possible
- Very unlikely
- Impossible
Next to each yellow hat contribution, note down where it...
PDF Summary Chapter 6: The Green Hat
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Though the yellow and green hats are complementary, and can be used in tandem to generate and develop ideas, they’re not the same type of thinking.
Po and the Stone That Jolts the Wheel out of the Rut
Green hat thinking is about jolting yourself out of your normal thinking patterns. Think of a horse-drawn carriage being driven along a dirt track. Though the whole path is available to the carriage, it quickly settles into the ruts left by previous carriages. The wheels will stay in the ruts until they’re jolted out, either through an input of deliberate energy from the driver and horses or by an obstacle such as a stone.
Similarly, thinking will tend to follow normal, well-traveled pathways unless something gets put in the road. A provocation is a mental stone in the rut of normal thinking. A provocation might be something like “People should be paid to have pets” or “A manager’s subordinates should decide whether or not she gets promoted.”
Po, standing for “provocative operation,” is a word you can use to signpost a provocation. The deal is that you’re not allowed to meet a po with a black hat—you have to run with the suggestion. Here are some...
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