── ── Mental model
Six Thinking Hats
Six Thinking Hats (Edward de Bono, 1985) prevents the most common meeting failure: different thinking modes colliding simultaneously. The fix is parallel thinking — everyone uses the same mode at the same time. Six hats: White (data/facts), Red (gut/emotions), Black (caution/risk), Yellow (optimism/value), Green (creativity/alternatives), Blue (process/meta).
Run Six Thinking Hats on a real problem
Bring something you're actually deciding — free, in the browser.
How it works
Six phases → Six Hats Analysis. Stop rule: if Blue Hat close reveals no dominant direction, identify the most contested hat phase and schedule a focused session on it alone rather than forcing a decision.
1. Blue Hat opens (5 min): Define the question, hat sequence, time limits, and rules (no switching modes during a hat phase). 2. White Hat — facts and data (10 min): State known facts only. Distinguish confirmed data from soft data. List information gaps explicitly. 3. Yellow Hat — optimism and value (8 min): Generate specific benefits with logical basis. Run before Black to prevent habitual pessimism dominating. 4. Black Hat — caution and risk (10 min): Identify specific, evidence-based risks. "I don't like it" is Red Hat. "The API will fail under rate limits because X" is Black Hat. Do not abbreviate. 5. Green Hat — creativity and alternatives (8 min): Generate alternatives — no evaluation. Facilitator must actively block Black Hat intrusions. 6. Red Hat — gut feeling (2 min, 30 sec per person): One sentence per person, no justification required or permitted. 7. Blue Hat closes (5 min): Synthesize decision, action items, most critical Black Hat risk, most promising Green Hat direction.
When to use it
- group decision degenerates into debate
- proposal needs multi-angle evaluation
- creative ideas get killed by habitual criticism
- someone says "let's look at this from all angles," "we keep going in circles," "we need structure"
- individual high-stakes decision needs forced multi-angle review
- a platform-shift bet needs balanced evaluation (e.g. "should we go all-in on AI agents / AI-native," "is our AI capex justified," "how do we weigh AI adoption risk vs
When not to use it
the question has a clear empirical answer (use critical-thinking instead), or time is under 10 minutes and no setup is possible.
Worked example
ABB Global Management Meetings (1990s)
A primary-source-documented case. Percy Barnevik, CEO of ABB (the Swedish-Swiss engineering conglomerate) from 1988 to 1996, documented the adoption of the Six Hats method in ABB's management structure in interviews and in de Bono's subsequent documentation of the case.
Install this skill (free, MIT)
npx skills add deciqAI/knowledge-skillsUseful? Star the repo — stars help other builders find it.
FAQ
What do the six hats stand for?
White: data and facts. Red: gut feel and emotion. Black: caution and risk. Yellow: optimism and value. Green: creative alternatives. Blue: process control — managing which hat the group wears. Each hat is a thinking mode the whole group enters together.
What problem do the Six Thinking Hats solve?
Mode collision: in normal meetings one person is generating ideas while another attacks risks and a third recites data, so every idea is judged the moment it's born. Parallel thinking — everyone in the same mode simultaneously — separates generation from evaluation and defuses ego battles.
How do you run a Six Hats session?
The facilitator (Blue) sets a sequence suited to the decision — for example White (facts), Green (options), Yellow (upside), Black (risks), Red (gut check), Blue (decide) — and the whole group wears each hat for a few minutes. The discipline is refusing cross-mode interruptions: risk talk waits for the Black hat.
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