The Art of Thinking Clearly by Rolf Dobelli is a collection of 99 short chapters, each examining a common cognitive bias, fallacy, or thinking error. Dobelli’s core message is that clearer thinking comes less from adding clever strategies and more from systematically avoiding these predictable traps. Below is a chapter-by-chapter summary in the requested format.

1. Why You Should Visit Cemeteries: Survivorship Bias

Key insight: We overestimate success odds because we only see the winners; the far larger number of failures remains invisible.

• Actively seek out and study failures (the “cemeteries”).
• Ask what the unsuccessful majority looked like before drawing conclusions from success stories.
• Treat media success narratives with skepticism.

2. Does Harvard Make You Smarter?: Swimmer’s Body Illusion

Key insight: We confuse selection factors with results (swimmers have the body that makes them good at swimming; elite schools select the already talented).

• Separate innate advantages or prior selection from the effects of training or education.
• Question whether a prestigious institution or method actually causes the observed outcome.
• Avoid copying surface traits of successful people without understanding selection.

3. Why You See Shapes in the Clouds: Clustering Illusion

Key insight: The brain is oversensitive to patterns and invents them even in pure randomness.

• Default to “chance” when you spot a pattern until statistical evidence proves otherwise.
• Demand proper statistical testing before acting on apparent correlations.
• Remain skeptical of “hot streaks” or meaningful clusters in data.

4. If Fifty Million People Say Something Foolish, It Is Still Foolish: Social Proof

Key insight: We treat popularity as evidence of correctness (herd instinct).

• Evaluate ideas on their own merits, not on how many people hold them.
• Pause when you feel pressure to conform simply because others are doing something.
• Be especially wary in uncertain or high-stakes situations.

5. Why You Should Forget the Past: Sunk Cost Fallacy

Key insight: Past investments (time, money, effort) should not dictate future decisions.

• Evaluate only future costs and benefits.
• Be willing to abandon projects once they no longer make sense, regardless of prior outlay.
• Recognize the emotional pull of consistency and “not wasting” what is already gone.

6. Don’t Accept Free Drinks: Reciprocity

Key insight: We feel obligated to return favors even when they were unsolicited.

• Recognize free gifts or favors as potential influence tactics.
• Decide based on the actual value of what is being offered, not the sense of debt.
• Politely decline unsolicited gifts when they create pressure.

7. Beware the “Special Case”: Confirmation Bias (Part 1)

Key insight: We interpret new information so that it fits existing beliefs and dismiss contradictory evidence.

• Actively hunt for disconfirming evidence.
• Treat “special cases” that rescue a theory with suspicion.
• Write down core beliefs and deliberately challenge them.

8. Murder Your Darlings: Confirmation Bias (Part 2)

Key insight: We cling to cherished ideas even after they have been disproven.

• Be willing to kill favorite theories or strategies when evidence turns against them.
• Seek out people and sources that disagree with you.
• Practice changing your mind publicly when warranted.

9. Don’t Bow to Authority: Authority Bias

Key insight: We give excessive weight to the opinions of authority figures.

• Evaluate the content of the advice, not the status of the speaker.
• Ask what evidence or track record supports the authority’s claim.
• Create environments where subordinates can safely challenge superiors.

10. Leave Your Supermodel Friends at Home: Contrast Effect

Key insight: Judgments are distorted by what we compare things against.

• Judge options in isolation or against relevant benchmarks, not extreme contrasts.
• Be aware that a mediocre option looks better next to a poor one (and vice versa).
• Avoid sequential presentations designed to manipulate relative attractiveness.

11. Why We Prefer a Wrong Map to None at All: Availability Bias

Key insight: We construct our picture of the world from whatever comes most easily to mind.

• Seek base rates and less vivid but more representative data.
• Spend time with people whose experiences differ from yours.
• Question whether vivid examples are actually typical.

12. Why “No Pain, No Gain” Should Set Alarm Bells Ringing: The It’ll-Get-Worse-Before-It-Gets-Better Fallacy

Key insight: We accept temporary deterioration as proof that a strategy is working, even when it is not.

• Demand clear metrics that distinguish necessary short-term pain from failure.
• Set decision rules in advance for when to abandon a worsening course.
• Be wary of advisors who use this narrative to buy time.

13. Even True Stories Are Fairy Tales: Story Bias

Key insight: We prefer coherent stories to messy reality and therefore overlook omitted facts.

• Look for what has been left out of any neat narrative.
• Prefer statistical distributions over single anecdotes.
• Resist the urge to force events into a clean cause-and-effect story.

14. Why You Should Keep a Diary: Hindsight Bias

Key insight: After an event occurs, we believe we “knew it all along.”

• Keep contemporaneous records of predictions and reasoning.
• Review past forecasts honestly rather than rewriting them.
• Use the diary to calibrate your actual forecasting skill.

15. Why You Systematically Overestimate Your Knowledge and Abilities: Overconfidence Effect

Key insight: We systematically overestimate our knowledge, skills, and predictive accuracy.

• Seek external feedback and objective measures.
• Express confidence intervals rather than point estimates.
• Assume you know less than you think, especially in complex domains.

16. Don’t Take News Anchors Seriously: Chauffeur Knowledge

Key insight: We confuse fluent presentation with genuine expertise.

• Distinguish “knowing how to talk about something” from deep understanding.
• Probe for real knowledge rather than polished talking points.
• Prefer specialists who can admit limits over smooth generalists.

17. You Control Less Than You Think: Illusion of Control

Key insight: We overestimate our influence over outcomes that are largely random or external.

• Distinguish what is truly under your control from what is not.
• Focus effort on the controllable factors.
• Accept that many results are driven by chance or larger systems.

18. Never Pay Your Lawyer by the Hour: Incentive Super-Response Tendency

Key insight: People respond strongly (and often perversely) to the incentives they face.

• Align incentives with desired outcomes.
• Anticipate how others will game the system.
• Prefer fixed-fee or outcome-based arrangements where possible.

19. The Dubious Efficacy of Doctors, Consultants and Psychotherapists: Regression to the Mean

Key insight: Extreme results tend to be followed by more average ones; we misattribute the improvement.

• Expect regression after unusually good or bad performance.
• Do not credit interventions for natural reversion to the mean.
• Use control groups or longer baselines when evaluating effectiveness.

20. Never Judge a Decision by Its Outcome: Outcome Bias

Key insight: We judge the quality of a decision by its result rather than by the information available at the time.

• Evaluate decisions on process and information quality, not hindsight results.
• Separate luck from skill when reviewing outcomes.
• Avoid punishing good decisions that happened to turn out poorly.

21. Less Is More: The Paradox of Choice

Key insight: More options often lead to more anxiety, paralysis, and lower satisfaction.

• Limit the number of alternatives you consider.
• Decide on decision criteria first, then choose.
• Accept “good enough” rather than endlessly searching for the optimal.

22. You Like Me, You Really Really Like Me: Liking Bias

Key insight: We favor people we like and are more easily influenced by them.

• Separate personal liking from the quality of the proposal or product.
• Be aware when sales or persuasion tactics rely on rapport.
• Make important decisions based on merits, not affinity.

23. Don’t Cling to Things: Endowment Effect

Key insight: We value things more highly simply because we own them.

• Imagine you do not own the item when deciding whether to keep or sell it.
• Use market prices rather than personal attachment as the guide.
• Be willing to part with possessions that no longer serve you.

24. The Inevitability of Unlikely Events: Coincidence

Key insight: Unlikely events happen regularly simply because so many opportunities exist.

• Do not over-interpret coincidences as meaningful.
• Remember the law of large numbers in everyday life.
• Avoid assigning causal stories to random concurrent events.

25. The Calamity of Conformity: Groupthink

Key insight: Groups suppress dissent and converge on suboptimal decisions to maintain harmony.

• Actively encourage devil’s advocates and dissenting views.
• Structure decision processes to surface disagreement.
• Value independent judgment over group consensus for its own sake.

26. Why You’ll Soon Be Playing Megatrillions: Neglect of Probability

Key insight: We ignore or poorly weight actual probabilities, especially for rare events.

• Explicitly estimate base rates and probabilities.
• Do not let the emotional vividness of an outcome override its likelihood.
• Use expected-value thinking for significant decisions.

27. Why the Last Cookie in the Jar Makes Your Mouth Water: Scarcity Error

Key insight: We value things more when they appear scarce or limited.

• Ask whether scarcity is real or manufactured.
• Decide based on absolute value, not relative rarity.
• Resist urgency tactics that play on fear of missing out.

28. When You Hear Hoofbeats, Don’t Expect a Zebra: Base-Rate Neglect

Key insight: We ignore general statistical frequencies in favor of specific case details.

• Always start with the base rate of the category.
• Update with case-specific information only after establishing the prior.
• Beware of vivid stories that make rare events seem common.

29. Why the “Balancing Force of the Universe” Is Baloney: Gambler’s Fallacy

Key insight: We believe that past random outcomes influence future independent ones.

• Treat independent events as independent.
• Do not expect “due” outcomes after streaks.
• Reset expectations after every independent trial.

30. Why the Wheel of Fortune Makes Our Heads Spin: The Anchor

Key insight: Arbitrary numbers or first pieces of information heavily influence subsequent judgments.

• Generate your own independent estimate before seeing anchors.
• Be aware of opening offers and suggested prices.
• Adjust deliberately away from the first number presented.

31. How to Relieve People of Their Millions: Induction

Key insight: We extrapolate too confidently from limited past observations.

• Recognize that past patterns can break.
• Prefer theories with explanatory power over pure induction.
• Remain open to black-swan events that invalidate prior trends.

32. Why Evil Strikes Harder Than Good: Loss Aversion

Key insight: Losses hurt roughly twice as much as equivalent gains please us.

• Frame decisions in terms of overall wealth or long-term outcomes.
• Be willing to accept small, certain losses to avoid larger risks.
• Notice when loss aversion is keeping you stuck.

33. Why Teams Are Lazy: Social Loafing

Key insight: Individuals reduce effort when working in groups because responsibility is diffused.

• Make individual contributions measurable and visible.
• Keep teams small when possible.
• Assign clear personal accountability.

34. Stumped by a Sheet of Paper: Exponential Growth

Key insight: We chronically underestimate the power of exponential processes.

• Learn to calculate and visualize exponential curves.
• Apply the concept to debt, population, technology, and compounding.
• Do not rely on linear intuition for growth phenomena.

35. Curb Your Enthusiasm: Winner’s Curse

Key insight: The winner of an auction or competitive bid often overpays.

• Bid conservatively and account for the winner’s curse.
• Set a maximum value in advance and stick to it.
• Prefer sealed or carefully structured bidding processes.

36. Never Ask a Writer If the Novel Is Autobiographical: Fundamental Attribution Error

Key insight: We over-attribute behavior to personality and under-attribute it to situations.

• Consider situational pressures before judging character.
• Apply the same charitable interpretation to others that you apply to yourself.
• Look for external constraints when explaining actions.

37. Why You Shouldn’t Believe in the Stork: False Causality

Key insight: We confuse correlation with causation.

• Ask what third factors or reverse causality might explain the link.
• Prefer controlled experiments or strong causal designs.
• Be skeptical of causal claims based solely on observed association.

38. Everyone Is Beautiful at the Top: Halo Effect

Key insight: One positive trait colors our overall judgment of a person or product.

• Evaluate attributes independently.
• Separate appearance, charisma, or status from competence.
• Use structured criteria rather than global impressions.

39. Congratulations! You’ve Won Russian Roulette: Alternative Paths

Key insight: We ignore the many paths that could have led to different outcomes and focus only on the one that occurred.

• Consider the full distribution of possible results, not just the realized one.
• Ask “what else could have happened?”
• Avoid survivorship-style storytelling about single successful paths.

40. False Prophets: Forecast Illusion

Key insight: Experts and non-experts alike are poor at forecasting complex events, yet we over-rely on predictions.

• Treat most forecasts with heavy skepticism.
• Prefer ranges and scenarios over precise point predictions.
• Evaluate forecasters by track record, not confidence or credentials alone.

41. The Deception of Specific Cases: Conjunction Fallacy

Key insight: We judge a more specific combination of events as more probable than a single broader event.

• Remember that adding details can only decrease or keep probability the same.
• Prefer the more general statement when assessing likelihood.
• Watch for stories that feel more “representative” but are less probable.

42. It’s Not What You Say, but How You Say It: Framing

Key insight: The same information presented differently leads to different decisions.

• Reframe problems in multiple ways (gains vs. losses, percentages vs. absolute numbers).
• Look for the underlying facts independent of presentation.
• Be alert to framing used in marketing, politics, and negotiations.

43. Why Watching and Waiting Is Torture: Action Bias

Key insight: In uncertain situations we feel compelled to act even when inaction is better.

• Default to “do nothing” unless action has a clear positive expected value.
• Distinguish activity from progress.
• Create deliberate waiting periods for important decisions.

44. Why You Are Either the Solution – or the Problem: Omission Bias

Key insight: We judge harmful actions more harshly than equally harmful inactions.

• Evaluate the consequences of both acting and not acting.
• Do not let the moral weight of commission versus omission distort expected-value calculations.
• Accept responsibility for outcomes of deliberate inaction.

45. Don’t Blame Me: Self-Serving Bias

Key insight: We attribute successes to ourselves and failures to external factors.

• Seek objective feedback and third-party perspectives.
• Conduct pre-mortems and post-mortems that examine your own contribution.
• Practice attributing both good and bad outcomes more even-handedly.

46. Be Careful What You Wish For: Hedonic Treadmill

Key insight: We quickly adapt to improved circumstances and return to a baseline level of happiness.

• Pursue experiences and relationships that resist adaptation more than material gains.
• Lower expectations rather than constantly raising the bar.
• Focus on process and present enjoyment rather than permanent elevation of mood.

47. Do Not Marvel at Your Existence: Self-Selection Bias

Key insight: We observe only the situations we are in and therefore misjudge probabilities.

• Recognize that your presence itself selects the sample you see.
• Adjust for the fact that you only experience the paths that led to your current position.
• Use broader data rather than personal existence as evidence.

48. Why Experience Can Damage Our Judgement: Association Bias

Key insight: We form associations that are not causal and then act on them.

• Test whether the association is causal or merely correlational.
• Avoid letting incidental pairings (place, person, timing) dictate future decisions.
• Update beliefs when associations prove unreliable.

49. Be Wary When Things Get Off to a Great Start: Beginner’s Luck

Key insight: Early success is often due to chance and can create overconfidence.

• Treat initial wins as provisional.
• Continue rigorous evaluation even after early positive results.
• Avoid scaling strategies solely on the basis of beginner’s luck.

50. Sweet Little Lies: Cognitive Dissonance

Key insight: We rationalize conflicting beliefs or actions to reduce psychological discomfort.

• Notice when you are generating justifications after the fact.
• Prefer changing behavior or beliefs over elaborate rationalization.
• Invite external challenge to your post-hoc stories.

51. Live Each Day as If It Were Your Last – But Only on Sundays: Hyperbolic Discounting

Key insight: We heavily discount future rewards relative to immediate ones, inconsistently.

• Use commitment devices and pre-commitments.
• Make future consequences more vivid and immediate.
• Prefer rules and systems over relying on momentary willpower.

52. Any Lame Excuse: “Because” Justification

Key insight: Providing any reason (even a weak one) increases compliance.

• Distinguish real reasons from placeholder justifications.
• Demand substantive explanations.
• Be aware of the power of the word “because” in persuasion.

53. Decide Better – Decide Less: Decision Fatigue

Key insight: The quality of decisions declines after a series of choices.

• Make important decisions early in the day or after rest.
• Automate or reduce low-stakes decisions.
• Preserve mental energy for high-impact choices.

54. Would You Wear Hitler’s Sweater?: Contagion Bias

Key insight: We treat objects as carrying the essence of people or events associated with them.

• Separate symbolic contamination from actual properties.
• Evaluate items on functional merits rather than history alone.
• Recognize the emotional power of contamination narratives.

55. Why There Is No Such Thing as an Average War: The Problem with Averages

Key insight: Averages can hide important variation and non-linear effects.

• Look at distributions, not just means.
• Be cautious when the average is not representative of typical cases.
• Consider extremes and tails when they matter.

56. How Bonuses Destroy Motivation: Motivation Crowding

Key insight: Extrinsic rewards can crowd out intrinsic motivation.

• Use monetary incentives carefully, especially for creative or pro-social work.
• Preserve autonomy and purpose where possible.
• Monitor whether incentives are undermining the very behavior they aim to encourage.

57. If You Have Nothing to Say, Say Nothing: Twaddle Tendency

Key insight: We produce and accept empty, complex language that sounds intelligent but says little.

• Prefer clear, simple expression.
• Challenge jargon and vague statements.
• Value substance over sophisticated-sounding fluff.

58. How to Increase the Average IQ of Two States: Will Rogers Phenomenon

Key insight: Moving items between groups can improve averages in both groups without any real improvement.

• Watch for reclassification effects when evaluating group statistics.
• Examine composition changes before celebrating average gains.
• Prefer absolute measures over relative group averages when possible.

59. If You Have an Enemy, Give Him Information: Information Bias

Key insight: We seek information even when it will not affect the decision.

• Ask whether additional data will change the action.
• Stop gathering information once the decision threshold is reached.
• Distinguish decision-relevant information from interesting but useless data.

60. Hurts So Good: Effort Justification

Key insight: We value outcomes more highly when we have suffered to achieve them.

• Evaluate results independently of the effort expended.
• Avoid escalating commitment simply because the path was hard.
• Recognize that pain does not automatically confer value.

61. Why Small Things Loom Large: The Law of Small Numbers

Key insight: We over-interpret results from small samples.

• Demand larger samples before drawing strong conclusions.
• Expect more volatility in small groups or short time periods.
• Treat anecdotal or tiny-n findings as provisional.

62. Handle with Care: Expectations

Key insight: Expectations shape both perception and actual outcomes (placebo, self-fulfilling prophecy).

• Manage expectations consciously.
• Be aware of how your expectations influence others’ performance.
• Test whether results are driven by the intervention or by expectation effects.

63. Speed Traps Ahead!: Simple Logic

Key insight: We prefer simple explanations and solutions even when the problem is complex.

• Resist oversimplification of multifaceted issues.
• Accept that some problems require nuanced, multi-factor approaches.
• Prefer accurate complexity over elegant but wrong simplicity when stakes are high.

64. How to Expose a Charlatan: Forer Effect

Key insight: We accept vague, general personality descriptions as uniquely accurate.

• Demand specific, falsifiable claims.
• Test whether the description would fit almost anyone.
• Be skeptical of horoscopes, generic profiles, and flattering assessments.

65. Volunteer Work Is for the Birds: Volunteer’s Folly

Key insight: Unpaid work is not automatically more valuable or virtuous than paid alternatives.

• Compare opportunity costs of volunteering versus earning and donating.
• Value effectiveness over the feeling of contribution.
• Choose high-impact uses of time and money.

66. Why You Are a Slave to Your Emotions: Affect Heuristic

Key insight: Emotional reactions substitute for careful analysis of risks and benefits.

• Separate emotional response from analytical evaluation.
• Use structured tools when feelings are strong.
• Notice when liking or disliking is driving the judgment.

67. Be Your Own Heretic: Introspection Illusion

Key insight: We overestimate the accuracy of our own self-insight and undervalue external evidence.

• Treat your own introspections as hypotheses, not facts.
• Seek behavioral evidence and outside perspectives.
• Be more skeptical of your own motives than of others’.

68. Why You Should Set Fire to Your Ships: Inability to Close Doors

Key insight: We keep options open even when doing so is costly.

• Deliberately close low-value options to free attention and resources.
• Commit fully when the expected value is clear.
• Recognize the hidden cost of optionality.

69. Disregard the Brand New: Neomania

Key insight: We overvalue novelty simply because it is new.

• Evaluate innovations on actual benefits, not newness.
• Prefer proven solutions unless the new option clearly outperforms.
• Resist fashion-driven adoption.

70. Why Propaganda Works: Sleeper Effect

Key insight: The influence of a message can grow over time as we forget the untrustworthy source.

• Record the source of information along with the content.
• Re-evaluate claims when the source is later revealed as biased.
• Be aware that discounted messages can still shape attitudes later.

71. Why It’s Never Just a Two-Horse Race: Alternative Blindness

Key insight: We focus on the options presented and ignore better alternatives that were not listed.

• Explicitly generate additional options.
• Ask “what else could we do?”
• Expand the choice set before deciding.

72. Why We Take Aim at Young Guns: Social Comparison Bias

Key insight: We feel threatened by talented newcomers and may undermine them.

• Separate personal status concerns from organizational or team benefit.
• Actively support high performers even when they outshine you.
• Measure success by collective results rather than relative standing.

73. Why First Impressions Deceive: Primacy and Recency Effects

Key insight: Items presented first or last receive disproportionate weight.

• Be aware of order effects in lists, interviews, and presentations.
• Review information multiple times in different sequences.
• Weight middle items more carefully.

74. Why You Can’t Beat Home-Made: Not-Invented-Here Syndrome

Key insight: We undervalue ideas that originate outside our own group.

• Evaluate external ideas on merit, not origin.
• Actively seek and reward outside solutions.
• Create processes that overcome internal bias against external innovation.

75. How to Profit from the Implausible: The Black Swan

Key insight: Rare, high-impact events are both more consequential and less predictable than we assume.

• Build robustness and optionality against extreme events.
• Do not rely solely on historical frequencies for tail risks.
• Position yourself to benefit from positive black swans while limiting downside.

76. Knowledge Is Non-Transferable: Domain Dependence

Key insight: Expertise in one domain often fails to transfer to another.

• Do not assume skill in one area automatically confers skill elsewhere.
• Re-learn and re-test when moving domains.
• Value domain-specific experience.

77. The Myth of Like-Mindedness: False-Consensus Effect

Key insight: We overestimate how much others share our beliefs and preferences.

• Actively sample outside your usual circles.
• Test assumptions about what “everyone” thinks.
• Design for diversity of opinion rather than assumed consensus.

78. You Were Right All Along: Falsification of History

Key insight: We rewrite our past beliefs and predictions to appear more consistent with what actually happened.

• Keep contemporaneous records.
• Compare current recollections with original statements.
• Accept that your past self was often wrong.

79. Why You Identify with Your Football Team: In-Group Out-Group Bias

Key insight: We favor our own group and denigrate outsiders, often on arbitrary grounds.

• Recognize the arbitrary nature of many group boundaries.
• Apply the same standards to in-group and out-group members.
• Seek contact and cooperation across groups.

80. The Difference Between Risk and Uncertainty: Ambiguity Aversion

Key insight: We prefer known risks over unknown uncertainties even when the unknown may be better.

• Distinguish measurable risk from true uncertainty.
• Do not automatically prefer the known quantity.
• Develop methods for acting under genuine uncertainty.

81. Why You Go with the Status Quo: Default Effect

Key insight: We stick with pre-selected options far more than is rational.

• Treat defaults as choices that still require evaluation.
• Design defaults carefully when you set them for others.
• Periodically review whether the status quo remains optimal.

82. Why “Last Chances” Make Us Panic: Fear of Regret

Key insight: Anticipated regret drives many decisions, often suboptimally.

• Focus on expected value rather than possible future regret.
• Accept that some regret is inevitable.
• Make decisions you can defend to your future self on process grounds.

83. How Eye-Catching Details Render Us Blind: Salience Effect

Key insight: Vivid, attention-grabbing features dominate judgment while more important but less noticeable factors are ignored.

• Deliberately look for less salient but higher-impact variables.
• Use checklists to force attention to quiet factors.
• Discount dramatic details that are statistically minor.

84. Why Money Is Not Naked: House-Money Effect

Key insight: We treat money differently depending on how we obtained it (more carelessly with “found” or won money).

• Treat all money as fungible.
• Make decisions based on total wealth, not mental accounts.
• Avoid riskier behavior with windfall gains.

85. Why New Year’s Resolutions Don’t Work: Procrastination

Key insight: We delay aversive tasks even when the delay is costly.

• Break tasks into smaller, immediate next actions.
• Use deadlines, accountability, and environmental design.
• Reduce the friction of starting.

86. Build Your Own Castle: Envy

Key insight: Comparing ourselves to others generates unhappiness and poor decisions.

• Focus on your own absolute progress rather than relative standing.
• Limit exposure to envy-inducing comparisons.
• Celebrate others’ success without measuring yourself against it.

87. Why You Prefer Novels to Statistics: Personification

Key insight: We respond more strongly to individual stories than to statistical aggregates.

• Balance personal stories with base-rate data.
• Use both narrative and numbers.
• Be aware when a single vivid case is being used to override broader evidence.

88. You Have No Idea What You Are Overlooking: Illusion of Attention

Key insight: We believe we notice far more of our environment than we actually do.

• Accept the severe limits of attention.
• Design systems and environments that do not rely on continuous vigilance.
• Use external checks for important details.

89. Hot Air: Strategic Misrepresentation

Key insight: People deliberately overstate benefits and understate costs to get projects approved.

• Apply independent scrutiny to forecasts and budgets.
• Build in buffers and contingency for optimistic projections.
• Hold proposers accountable for earlier estimates.

90. Where’s the Off Switch?: Overthinking

Key insight: Excessive analysis can paralyze action or degrade decision quality.

• Set decision deadlines.
• Distinguish reversible from irreversible choices and act faster on the former.
• Stop gathering information once further data will not change the choice.

91. Why You Take On Too Much: Planning Fallacy

Key insight: We systematically underestimate the time, costs, and risks of future tasks.

• Use reference-class forecasting (how long similar projects actually took).
• Add explicit buffers.
• Break plans into smaller parts and track early progress.

92. Those Wielding Hammers See Only Nails: Déformation Professionnelle

Key insight: Professional training causes us to see every problem through the lens of our specialty.

• Consult people from other disciplines.
• Question whether your preferred tool is actually the right one.
• Expand your toolkit deliberately.

93. Mission Accomplished: Zeigarnik Effect

Key insight: Unfinished tasks occupy more mental space than completed ones.

• Capture open loops in a trusted system.
• Complete or deliberately abandon tasks to free attention.
• Use the effect positively by starting tasks to create psychological pull.

94. The Boat Matters More Than the Rowing: Illusion of Skill

Key insight: In domains dominated by chance, we over-attribute results to skill.

• Identify the relative contributions of skill versus luck.
• Do not overpay for perceived skill in high-randomness fields.
• Focus skill development where it actually matters.

95. Why Checklists Deceive You: Feature-Positive Effect

Key insight: We notice presence more readily than absence.

• Explicitly check for missing features or non-events.
• Use structured lists that force attention to what is not there.
• Be wary of conclusions drawn only from positive instances.

96. Drawing the Bull’s-Eye Around the Arrow: Cherry-Picking

Key insight: We select evidence that supports a preferred conclusion and ignore the rest.

• Examine the full set of relevant data.
• Pre-specify what would count as confirming or disconfirming evidence.
• Be suspicious of post-hoc selection of favorable cases.

97. The Stone-Age Hunt for Scapegoats: Fallacy of the Single Cause

Key insight: We look for one simple cause when outcomes usually have multiple interacting causes.

• Map multiple contributing factors.
• Avoid single-cause explanations for complex events.
• Design interventions that address several drivers.

98. Speed Demons Make Safe Drivers: Intention-to-Treat Error

Key insight: We evaluate interventions based on those who completed them rather than those originally assigned.

• Analyze by original intention or assignment.
• Account for dropouts and non-compliance.
• Prefer intention-to-treat analyses for real-world effectiveness.

99. Why You Shouldn’t Read the News: News Illusion

Key insight: News focuses on the dramatic, immediate, and exceptional, distorting our picture of reality.

• Limit news consumption.
• Prefer slower, deeper sources and base-rate information.
• Recognize that most news is irrelevant to long-term decisions and well-being.