The original sequences were a series of essays written by Eliezer Yudkowsky between 2006 and 2009 on the blogs Overcoming Bias and Less Wrong. About half of these essays were organized into a number of thematically linked "sequences" of blog posts--hence the name.

In 2015, these sequences were edited into an ebook, Rationality: From AI to Zombies. The ebook leaves out some of the original posts, as well as adding some essays that were written by Yudkowsky during the same time but never previously collected into a named sequence. This page will serve to collect the older, deprecated sequences.

Of these, "Map and Territory," "Mysterious Answers to Mysterious Questions," "How to Actually Change Your Mind," and "Reductionism" were classified as "core sequences." There was also a distinction between "major" and "minor" sequences, though this was based on the size of the sequence rather than its importance.

Bolded essays are more important than other posts in the sequence, while italicized essays are relatively unimportant. Some essays are indented to indicate that they are tangents or self-contained elaborations upon a previous essay.

Other formats

The Sequences have been converted to eReader-compatible formats by several projects.

Two abridged indexes of Yudkowsky's sequences are XiXiDu's guide, or Academian's guide targeted at people who already have a science background.

Map and Territory

  1. The Simple Truth
  2. What Do We Mean By "Rationality"?
  3. An Intuitive Explanation of Bayes's Theorem
  4. Why truth? And...
  5. What is Evidence?
  6. How Much Evidence Does It Take?
  7. How to Convince Me That 2 + 2 = 3
  8. Occam's Razor
  9. The Lens That Sees Its Flaws

Mysterious Answers to Mysterious Questions

  1. Making Beliefs Pay Rent (in Anticipated Experiences)
  2. Belief in Belief
  3. Bayesian Judo
  4. Professing and Cheering
  5. Belief as Attire
  6. Focus Your Uncertainty
  7. The Virtue of Narrowness
  8. Your Strength As A Rationalist
  9. Absence of Evidence is Evidence of Absence
  10. Conservation of Expected Evidence
  11. Hindsight Bias
  12. Hindsight Devalues Science
  13. Fake Explanations
  14. Guessing the Teacher's Password
  15. Science as Attire
  16. Fake Causality
  17. Semantic Stopsigns
  18. Mysterious Answers to Mysterious Questions
  19. The Futility of Emergence
  20. Say Not "Complexity"
  21. Positive Bias: Look Into the Dark
  22. My Wild and Reckless Youth
  23. Failing to Learn from History
  24. Making History Available
  25. Explain/Worship/Ignore?
  26. "Science" as Curiosity-Stopper
  27. Applause Lights
  28. Truly Part of You
  29. Chaotic Inversion

How to Actually Change Your Mind

See also: Locating the hypothesis, Privileging the hypothesis, Litany of Gendlin, Litany of Tarski

Politics is the Mind-Killer

  1. A Fable of Science and Politics
  2. Politics is the Mind-Killer
  3. Policy Debates Should Not Appear One-Sided
  4. The Scales of Justice, the Notebook of Rationality
  5. Correspondence Bias
  6. Are Your Enemies Innately Evil?
  7. The Robbers Cave Experiment
  8. Reversed Stupidity is Not Intelligence
  9. Argument Screens Off Authority
  10. Hug the Query
  11. Rationality and the English Language
  12. The Litany Against Gurus
  13. Politics and Awful Art
  14. False Laughter
  15. Human Evil and Muddled Thinking

Death Spirals and the Cult Attractor

  1. The Affect Heuristic
  2. Evaluability and Cheap Holiday Shopping
  3. Unbounded Scales, Huge Jury Awards, & Futurism
  4. The Halo Effect
  5. Superhero Bias
  6. Mere Messiahs
  7. '''Affective Death Spirals
  8. Resist the Happy Death Spiral
  9. '''Uncritical Supercriticality
  10. Evaporative Cooling of Group Beliefs
  11. When None Dare Urge Restraint
  12. The Robbers Cave Experiment
  13. Every Cause Wants to be a Cult
  14. Guardians of the Truth
  15. Guardians of the Gene Pool
  16. Guardians of Ayn Rand
  17. The Litany Against Gurus
  18. Two Cult Koans
  19. Asch's Conformity Experiment
  20. Lonely Dissent
  21. Cultish Countercultishness

Seeing with Fresh Eyes

  1. Anchoring and Adjustment
  2. Priming and Contamination
  3. Do We Believe Everything We're Told?
  4. Cached Thoughts
  5. The 'Outside the Box' Box
  6. Original Seeing
  7. The Logical Fallacy of Generalization from Fictional Evidence
  8. How to Seem (and Be) Deep
  9. We Change Our Minds Less Often Than We Think
  10. Hold Off On Proposing Solutions
  11. Asch's Conformity Experiment
  12. On Expressing Your Concerns
  13. Lonely Dissent
  14. The Genetic Fallacy

Noticing Confusion

  1. Your Strength as a Rationalist
  2. Absence of Evidence Is Evidence of Absence
  3. Hindsight Bias
  4. Hindsight Devalues Science
  5. Positive Bias: Look Into the Dark

Against Rationalization

  1. Knowing About Biases Can Hurt People
  2. Update Yourself Incrementally
  3. One Argument Against An Army
  4. The Bottom Line
  5. What Evidence Filtered Evidence?
  6. Rationalization
  7. A Rational Argument
  8. Avoiding Your Belief's Real Weak Points
  9. Motivated Stopping and Motivated Continuation
  10. A Case Study of Motivated Continuation
  11. Fake Justification
  12. Fake Optimization Criteria
  13. Is That Your True Rejection?
  14. Entangled Truths, Contagious Lies
  15. Of Lies and Black Swan Blowups
  16. Anti-Epistemology
  17. The Sacred Mundane

Against Doublethink

  1. Singlethink
  2. Doublethink: Choosing to be Biased
  3. No, Really, I've Deceived Myself
  4. Belief in Self-Deception
  5. Moore's Paradox
  6. Don't Believe You'll Self-Deceive

Overly Convenient Excuses

  1. The Proper Use of Humility
  2. The Third Alternative
  3. Locating the hypothesis
  4. Privileging the Hypothesis
  5. But There's Still A Chance, Right?
  6. The Fallacy of Gray
  7. Absolute Authority
  8. How to Convince Me That 2 + 2 = 3
  9. Infinite Certainty
  10. 0 And 1 Are Not Probabilities

Letting Go

  1. Feeling Rational
  2. The Importance of Saying "Oops"
  3. The Crackpot Offer
  4. Just Lose Hope Already
  5. The Proper Use of Doubt
  6. You Can Face Reality
  7. The Meditation on Curiosity
  8. Something to Protect
  9. No One Can Exempt You From Rationality's Laws
  10. Leave a Line of Retreat
  11. Crisis of Faith
  12. The Ritual

The Simple Math of Evolution

  1. An Alien God
  2. The Wonder of Evolution
  3. Evolutions Are Stupid (But Work Anyway)
  4. Speed limit and complexity bound for evolution
  5. Adaptation-Executers, not Fitness-Maximizers
  6. No Evolutions for Corporations or Nanodevices
  7. Evolving to Extinction
  8. The Tragedy of Group Selectionism
  9. Fake Optimization Criteria

A Human's Guide to Words

  1. The Parable of the Dagger
  2. The Parable of Hemlock
  3. Words as Hidden Inferences
  4. Extensions and Intensions
  5. Similarity Clusters
  6. Typicality and Asymmetrical Similarity
  7. The Cluster Structure of Thingspace
  8. Disguised Queries
  9. Neural Categories
  10. How An Algorithm Feels From Inside
  11. Disputing Definitions
  12. Feel the Meaning
  13. The Argument From Common Usage
  14. Empty Labels
  15. Taboo Your Words
  16. Replace the Symbol with the Substance
  17. Fallacies of Compression
  18. Categorizing Has Consequences
  19. Sneaking in Connotations
  20. Arguing "By Definition"
  21. Where to Draw the Boundary?
  22. Entropy, and Short Codes
  23. Mutual Information, and Density in Thingspace
  24. Superexponential Conceptspace, and Simple Words
  25. Conditional Independence, and Naive Bayes
  26. Words as Mental Paintbrush Handles
  27. Variable Question Fallacies
  28. 37 Ways That Suboptimal Use Of Categories Can Have Negative Side Effects On our Cognition


Reductionism (i)

  1. Universal Fire
  2. Universal Law
  3. Dissolving the Question
  4. Wrong Questions
  5. Righting a Wrong Question
  6. Mind Projection Fallacy
  7. Probability is in the Mind
  8. The Quotation is not the Referent
  9. Qualitatively Confused
  10. Reductionism
  11. Explaining vs. Explaining Away
  12. Fake Reductionism
  13. Savanna Poets

Joy in the Merely Real

  1. Joy in the Merely Real
  2. Joy in Discovery
  3. Bind Yourself to Reality
  4. If You Demand Magic, Magic Won't Help
  5. Mundane Magic
  6. The Beauty of Settled Science
  7. Amazing Breakthrough Day: April 1st
  8. Is Humanism a Religion-Substitute?
  9. Scarcity
  10. To Spread Science, Keep It Secret
  11. Initiation Ceremony
  12. Awww, a Zebra

Reductionism (ii)

  1. Hand vs. Fingers
  2. Angry Atoms
  3. Heat vs. Motion
  4. Brain Breakthrough! It's Made of Neurons!
  5. Reductive Reference


  1. Zombies! Zombies?
  2. Zombie Responses
  3. The Generalized Anti-Zombie Principle
  4. GAZP vs. GLUT
  5. Belief in the Implied Invisible
  6. Zombies: The Movie
  7. Causal reference

Reductionism (iii)

  1. Excluding the Supernatural
  2. Psychic Powers

Quantum Physics

Basic Quantum Mechanics

  1. Quantum Explanations
  2. Configurations and Amplitude
  3. Joint Configurations
  4. Distinct Configurations
  5. Where Philosophy Meets Science
  6. Can You Prove Two Particles Are Identical?
  7. Classical Configuration Spaces
  8. The Quantum Arena
  9. Feynman Paths
  10. No Individual Particles
  11. Identity Isn't In Specific Atoms
  12. Decoherence
  13. The So-Called Heisenberg Uncertainty Principle
  14. Which Basis Is More Fundamental?
  15. Where Physics Meets Experience
  16. Where Experience Confuses Physicists
  17. On Being Decoherent
  18. The Conscious Sorites Paradox
  19. Decoherece is Pointless
  20. Decoherent Essences
  21. The Born Probabilities
  22. Decoherence as Projection
  23. Entangled Photons

Many Worlds

  1. Bell's Theorem: No EPR "Reality"
  2. Spooky Action at a Distance: The No-Communication Theorem
  3. Decoherence is Simple
  4. Decoherence is Falsifiable and Testable
  5. Quantum Non-Realism
  6. Collapse Postulates
  7. If Many-Worlds Had Come First
  8. Many Worlds, One Best Guess
  9. Living in Many Worlds

Timeless Physics

  1. Mach's Principle: Anti-Epiphenomenal Physics
  2. Relative Configuration Space
  3. Timeless Physics
  4. Timeless Beauty
  5. Timeless Causality
  6. Timeless Identity
  7. Thou Art Physics
  8. Timeless Control

Rationality and Science

  1. The Failures of Eld Science
  2. The Dilemma: Science or Bayes?
  3. Science Doesn't Trust Your Rationality
  4. When Science Can't Help
  5. Science Isn't Strict Enough
  6. Do Scientists Already Know This Stuff?
  7. No Safe Defense, Not Even Science
  8. Changing the Definition of Science
  9. Faster Than Science
  10. Einstein's Speed
  11. That Alien Message
  12. My Childhood Role Model
  13. Einstein's Superpowers
  14. Class Project
  15. Why Quantum?


  1. Heading Toward Morality
  2. No Universally Compelling Arguments
  3. 2-Place and 1-Place Words
  4. What Would You Do Without Morality?
  5. The Moral Void
  6. Created Already In Motion
  7. The Bedrock of Fairness
  8. Moral Complexities
  9. Is Morality Preference?
  10. Is Morality Given?
  11. Where Recursive Justification Hits Bottom
  12. My Kind of Reflection
  13. The Genetic Fallacy
  14. Fundamental Doubts
  15. Rebelling Within Nature
  16. Probability is Subjectively Objective
  17. Whither Moral Progress?
  18. The Gift We Give To Tomorrow
  19. Could Anything Be Right?
  20. Existential Angst Factory
  21. Can Counterfactuals Be True?
  22. Math is Subjunctively Objective
  23. Does Your Morality Care What You Think?
  24. Changing Your Metaethics
  25. Setting Up Metaethics
  26. The Meaning of Right
  27. Interpersonal Morality
  28. Morality as Fixed Computation
  29. Inseparably Right; or, Joy in the Merely Good
  30. Sorting Pebbles Into Correct Heaps
  31. Moral Error and Moral Disagreement
  32. Abstracted Idealized Dynamics
  33. "Arbitrary"
  34. Is Fairness Arbitrary?
  35. The Bedrock of Morality: Arbitrary?
  36. You Provably Can't Trust Yourself
  37. No License To Be Human
  38. Invisible Frameworks

Fun Theory

  1. Prolegomena to a Theory of Fun
  2. High Challenge
  3. Complex Novelty
  4. Continuous Improvement
  5. Sensual Experience
  6. Living By Your Own Strength
  7. Free to Optimize
  8. Harmful Options
  9. Devil's Offers
  10. Nonperson Predicates
  11. Amputation of Destiny
  12. Dunbar's Function
  13. In Praise of Boredom
  14. Sympathetic Minds
  15. Interpersonal Entanglement
  16. Failed Utopia #4-2
  17. Growing Up is Hard
  18. Changing Emotions
  19. Emotional Involvement
  20. Serious Stories
  21. Eutopia is Scary
  22. Building Weirdtopia
  23. Justified Expectation of Pleasant Surprises
  24. Seduced by Imagination
  25. The Uses of Fun (Theory)
  26. Higher Purpose

Ethical Injunctions

  1. Why Does Power Corrupt?
  2. Ends Don't Justify Means (Among Humans)
  3. Entangled Truths, Contagious Lies
  4. Protected From Myself
  5. Ethical Inhibitions
  6. Ethical Injunctions
  7. Prices or Bindings?
  8. Ethics Notes

Yudkowsky's Coming of Age

  1. My Childhood Death Spiral
  2. My Best and Worst Mistake
  3. Raised in Technophilia
  4. A Prodigy of Refutation
  5. The Sheer Folly of Callow Youth
  6. That Tiny Note of Discord
  7. Fighting a Rearguard Action Against the Truth
  8. My Naturalistic Awakening
  9. The Level Above Mine
  10. Competent Elites
  11. Above-Average AI Scientists
  12. The Magnitude of His Own Folly
  13. Beyond the Reach of God
  14. My Bayesian Enlightenment

Challenging the Difficult

  1. The Proper Use of Humility
  2. Tsuyoku Naritai (I Want To Become Stronger)
  3. Tsuyoku vs. the Egalitarian Instinct
  4. Guardians of the Truth
  5. Guardians of Ayn Rand
  6. Lotteries: A Waste of Hope
  7. New Improved Lottery
  8. The Failures of Eld Science
  9. Something to Protect
  10. Einstein's Superpowers
  11. Trying to Try
  12. Use the Try Harder, Luke
  13. On Doing the Impossible
  14. Make an Extraordinary Effort
  15. Shut Up and Do the Impossible

The Craft and the Community

  1. Raising the Sanity Waterline
  2. A Sense That More Is Possible
  3. Epistemic Viciousness
  4. Schools Proliferating Without Evidence
  5. 3 Levels of Rationality Verification
  6. Why Our Kind Can't Cooperate
  7. Tolerate Tolerance
  8. You're Calling Who A Cult Leader?
  9. On Things That Are Awesome
  10. Your Price For Joining
  11. Can Humanism Match Religion's Output?
  12. Church vs. Taskforce
  13. Rationality: Common Interest of Many Causes
  14. Helpless Individuals
  15. Money: The Unit of Caring
  16. Purchase Fuzzies and Utilons Separately
  17. Selecting Rationalist Groups
  18. Incremental Progress and the Valley
  19. Whining-Based Communities
  20. Mandatory Secret Identities
  21. Beware of Other-Optimizing
  22. Akrasia and Shangri-La
  23. Collective Apathy and the Internet
  24. Bayesians vs. Barbarians
  25. Of Gender and Rationality
  26. My Way
  27. The Sin of Underconfidence
  28. Well-Kept Gardens Die By Pacifism
  29. Practical Advice Backed By Deep Theories
  30. Less Meta
  31. Go Forth and Create the Art!