Ancient Knowledge ClubAn Essay Concerning Human UnderstandingJohn Locke

Guided edition

An Essay Concerning Human Understanding

by John Locke

Locke’s inquiry into where ideas come from and how people come to know anything at all.

Written 1690 143 guided readings Named English edition Read at your own pace

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The book stays at the centre.

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Original text first

Read the author's own words in a calm, focused layout.

Guidance in plain English

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Key takeaways for every chapter

Finish each chapter with the ideas worth carrying forward.

Inside this edition

Read it in the order it was written.

Each reading keeps the source, context, explanation and takeaways together.

BOOK I

CHAP. I.: IntroductionOriginal source, plain English guide and key takeaways

CHAP. II.: No Innate Principles In The Mind. Universal consent rejectedOriginal source, plain English guide and key takeaways

CHAP. II.: No Innate Principles In The Mind. Assent follows acquired ideasOriginal source, plain English guide and key takeaways

CHAP. II.: No Innate Principles In The Mind. Immediate assent follows learned ideas rather than innate inscriptionOriginal source, plain English guide and key takeaways

CHAP. II.: No Innate Principles In The Mind. Children expose the claimOriginal source, plain English guide and key takeaways

CHAP. III.: No Innate Practical Principles. Practical rules need proofOriginal source, plain English guide and key takeaways

CHAP. III.: No Innate Practical Principles. Moral disagreement challenges innate assent rather than natural lawOriginal source, plain English guide and key takeaways

CHAP. III.: No Innate Practical Principles. An innate rule must be clear, complete, and independently identifiableOriginal source, plain English guide and key takeaways

CHAP. III.: No Innate Practical Principles. Early authority can masquerade as nature unless principles remain examinableOriginal source, plain English guide and key takeaways

CHAP. IV.: Other Considerations Concerning Innate Principles, Both Speculative And Practical. Ideas required for innatenessOriginal source, plain English guide and key takeaways

CHAP. IV.: Other Considerations Concerning Innate Principles, Both Speculative And Practical. Universal consent proves nothingOriginal source, plain English guide and key takeaways

CHAP. IV.: Other Considerations Concerning Innate Principles, Both Speculative And Practical. Easy assent is not innatenessOriginal source, plain English guide and key takeaways

CHAP. IV.: Other Considerations Concerning Innate Principles, Both Speculative And Practical. Authority and self-knowledgeOriginal source, plain English guide and key takeaways

BOOK II

CHAP. I.: Of Ideas In General, And Their Original. Experience as the origin of ideasOriginal source, plain English guide and key takeaways

CHAP. I.: Of Ideas In General, And Their Original. Against always thinkingOriginal source, plain English guide and key takeaways

CHAP. I.: Of Ideas In General, And Their Original. From consciousness to sensationOriginal source, plain English guide and key takeaways

CHAP. II.: Of Simple IdeasOriginal source, plain English guide and key takeaways

CHAP. III.: Of Ideas Of One SenseOriginal source, plain English guide and key takeaways

CHAP. IV.: Of SolidityOriginal source, plain English guide and key takeaways

CHAP. VI.: Of Simple Ideas Of ReflectionOriginal source, plain English guide and key takeaways

CHAP. VII.: Of Simple Ideas Of Both Sensation And ReflectionOriginal source, plain English guide and key takeaways

CHAP. VIII.: Some Farther Considerations Concerning Our Simple Ideas. Ideas in the mind must be distinguished from powers in bodiesOriginal source, plain English guide and key takeaways

CHAP. VIII.: Some Farther Considerations Concerning Our Simple Ideas. Primary and secondary qualitiesOriginal source, plain English guide and key takeaways

CHAP. IX.: Of PerceptionOriginal source, plain English guide and key takeaways

CHAP. X.: Of RetentionOriginal source, plain English guide and key takeaways

CHAP. XI.: Of Discerning, And Other Operations Of The MindOriginal source, plain English guide and key takeaways

CHAP. XII.: Of Complex IdeasOriginal source, plain English guide and key takeaways

CHAP. XIII.: Of Simple Modes, And First Of The Simple Modes Of Space. Space becomes measurable through repetition, figure, and chosen relationsOriginal source, plain English guide and key takeaways

CHAP. XIII.: Of Simple Modes, And First Of The Simple Modes Of Space. Space is distinct from body, and unclear labels do not explain substanceOriginal source, plain English guide and key takeaways

CHAP. XIII.: Of Simple Modes, And First Of The Simple Modes Of Space. A disputed vacuum still shows that space and body are distinct ideasOriginal source, plain English guide and key takeaways

CHAP. XIV.: Of Duration, And Its Simple Modes. Time from thoughtOriginal source, plain English guide and key takeaways

CHAP. XIV.: Of Duration, And Its Simple Modes. Duration and its measureOriginal source, plain English guide and key takeaways

CHAP. XIV.: Of Duration, And Its Simple Modes. Measuring time beyond motionOriginal source, plain English guide and key takeaways

CHAP. XV.: Of Duration And Expansion, Considered TogetherOriginal source, plain English guide and key takeaways

CHAP. XVI.: Of NumberOriginal source, plain English guide and key takeaways

CHAP. XVII.: Of Infinity. Infinity as endless additionOriginal source, plain English guide and key takeaways

CHAP. XVII.: Of Infinity. Infinity as endless progressionOriginal source, plain English guide and key takeaways

CHAP. XVII.: Of Infinity. Infinity marks endless progression rather than a completed mental pictureOriginal source, plain English guide and key takeaways

CHAP. XVIII.: Of Other Simple ModesOriginal source, plain English guide and key takeaways

CHAP. XIX.: Of The Modes Of ThinkingOriginal source, plain English guide and key takeaways

CHAP. XX.: Of Modes Of Pleasure And PainOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of Power. From observed change to willOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of Power. Liberty belongs to agents who can act or forbear, not to the willOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of Power. Mind, will, and uneasinessOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of Power. Desire and volition distinguishedOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of Power. Immediate uneasiness moves action more reliably than distant acknowledged goodOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of Power. Freedom grows through suspending desire for fair examinationOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of Power. Suspension protects liberty while differing goods shape different livesOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of Power. Present pleasure distorts judgement when future consequences are measured unequallyOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of Power. Liberty checks haste, while practice reshapes what the mind finds rewardingOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of Power. Liberty preserves operative alternatives, while action differs from passive receptionOriginal source, plain English guide and key takeaways

CHAP. XXII.: Of Mixed ModesOriginal source, plain English guide and key takeaways

CHAP. XXIII.: Of Our Complex Ideas Of Substances. Substance as unknown supportOriginal source, plain English guide and key takeaways

CHAP. XXIII.: Of Our Complex Ideas Of Substances. Powers, human sight, and the obscurity of substanceOriginal source, plain English guide and key takeaways

CHAP. XXIII.: Of Our Complex Ideas Of Substances. Limits of body and spiritOriginal source, plain English guide and key takeaways

CHAP. XXIII.: Of Our Complex Ideas Of Substances. Even the highest idea of spirit remains composed from experienceOriginal source, plain English guide and key takeaways

CHAP. XXIV.: Of Collective Ideas Of SubstancesOriginal source, plain English guide and key takeaways

CHAP. XXV.: Of RelationOriginal source, plain English guide and key takeaways

CHAP. XXVI.: Of Cause And Effect, And Other RelationsOriginal source, plain English guide and key takeaways

CHAP. XXVII.: Of Identity And Diversity. Identity by beginningOriginal source, plain English guide and key takeaways

CHAP. XXVII.: Of Identity And Diversity. Personhood beyond substanceOriginal source, plain English guide and key takeaways

CHAP. XXVII.: Of Identity And Diversity. Consciousness unites the person across changes of substance and bodyOriginal source, plain English guide and key takeaways

CHAP. XXVII.: Of Identity And Diversity. Personal identity becomes a question of responsibilityOriginal source, plain English guide and key takeaways

CHAP. XXVIII.: Of Other Relations. Moral relation and its rulesOriginal source, plain English guide and key takeaways

CHAP. XXVIII.: Of Other Relations. Moral relations, social judgement, and clear comparisonOriginal source, plain English guide and key takeaways

CHAP. XXIX.: Of Clear And Obscure, Distinct And Confused Ideas. Confused ideas fail to preserve the distinctions their names promiseOriginal source, plain English guide and key takeaways

CHAP. XXIX.: Of Clear And Obscure, Distinct And Confused Ideas. Partial clarity can disguise the limits of a complex ideaOriginal source, plain English guide and key takeaways

CHAP. XXX.: Of Real And Fantastical IdeasOriginal source, plain English guide and key takeaways

CHAP. XXXI.: Of Adequate And Inadequate Ideas. Adequacy and its limitsOriginal source, plain English guide and key takeaways

CHAP. XXXI.: Of Adequate And Inadequate Ideas. Ideas of substances remain incomplete copies of their objectsOriginal source, plain English guide and key takeaways

CHAP. XXXII.: Of True And False Ideas. Falsehood rests in judgementOriginal source, plain English guide and key takeaways

CHAP. XXXII.: Of True And False Ideas. Rightness, wrongness, and referenceOriginal source, plain English guide and key takeaways

CHAP. XXXIII.: Of The Association Of IdeasOriginal source, plain English guide and key takeaways

BOOK III

CHAP. I.: Of Words Or Language In GeneralOriginal source, plain English guide and key takeaways

CHAP. II.: Of The Signification Of WordsOriginal source, plain English guide and key takeaways

CHAP. III.: Of General Terms. General terms from abstractionOriginal source, plain English guide and key takeaways

CHAP. III.: Of General Terms. General words and nominal essenceOriginal source, plain English guide and key takeaways

CHAP. III.: Of General Terms. Immutable essences as ideasOriginal source, plain English guide and key takeaways

CHAP. IV.: Of The Names Of Simple Ideas. Why simple names resist definitionOriginal source, plain English guide and key takeaways

CHAP. IV.: Of The Names Of Simple Ideas. When words can defineOriginal source, plain English guide and key takeaways

CHAP. V.: Of The Names Of Mixed Modes And Relations. Mind-made speciesOriginal source, plain English guide and key takeaways

CHAP. V.: Of The Names Of Mixed Modes And Relations. Names fix the boundaryOriginal source, plain English guide and key takeaways

CHAP. VI.: Of The Names Of Substances. Nominal essence sets the speciesOriginal source, plain English guide and key takeaways

CHAP. VI.: Of The Names Of Substances. Species names follow selected appearances rather than hidden constitutionsOriginal source, plain English guide and key takeaways

CHAP. VI.: Of The Names Of Substances. Definitions organise experience but can also excludeOriginal source, plain English guide and key takeaways

CHAP. VI.: Of The Names Of Substances. Human categories are constrained by nature without simply copying itOriginal source, plain English guide and key takeaways

CHAP. VI.: Of The Names Of Substances. Species are made by namingOriginal source, plain English guide and key takeaways

CHAP. VI.: Of The Names Of Substances. Mixed modes and substancesOriginal source, plain English guide and key takeaways

CHAP. VII.: Of ParticlesOriginal source, plain English guide and key takeaways

CHAP. VIII.: Of Abstract And Concrete TermsOriginal source, plain English guide and key takeaways

CHAP. IX.: Of The Imperfection Of Words. Shared words can conceal different moral ideasOriginal source, plain English guide and key takeaways

CHAP. IX.: Of The Imperfection Of Words. Substance names become unstable when inquiry demands precisionOriginal source, plain English guide and key takeaways

CHAP. IX.: Of The Imperfection Of Words. Language can obscure the knowledge it is meant to carryOriginal source, plain English guide and key takeaways

CHAP. X.: Of The Abuse Of Words. Empty and shifting terms turn argument into performanceOriginal source, plain English guide and key takeaways

CHAP. X.: Of The Abuse Of Words. A name does not prove that its supposed object existsOriginal source, plain English guide and key takeaways

CHAP. X.: Of The Abuse Of Words. Familiarity with a word does not create a shared meaningOriginal source, plain English guide and key takeaways

CHAP. X.: Of The Abuse Of Words. Ideas, names, and reality can fail to align in different waysOriginal source, plain English guide and key takeaways

CHAP. XI.: Of The Remedies Of The Foregoing Imperfections And Abuses. Clear inquiry begins by fixing the ideas under disputeOriginal source, plain English guide and key takeaways

CHAP. XI.: Of The Remedies Of The Foregoing Imperfections And Abuses. Different kinds of idea require different forms of explanationOriginal source, plain English guide and key takeaways

CHAP. XI.: Of The Remedies Of The Foregoing Imperfections And Abuses. Substance terms improve through observation, description, and consistent useOriginal source, plain English guide and key takeaways

BOOK IV

CHAP. I.: Of Knowledge In GeneralOriginal source, plain English guide and key takeaways

CHAP. II.: Of The Degrees Of Our Knowledge. Demonstration links immediate perceptions into a proofOriginal source, plain English guide and key takeaways

CHAP. II.: Of The Degrees Of Our Knowledge. Sensation gives practical certainty without demonstrationOriginal source, plain English guide and key takeaways

CHAP. III.: Of The Extent Of Human Knowledge. The limits of knowledge are narrower than the limits of thoughtOriginal source, plain English guide and key takeaways

CHAP. III.: Of The Extent Of Human Knowledge. The powers of substances are known mainly through experienceOriginal source, plain English guide and key takeaways

CHAP. III.: Of The Extent Of Human Knowledge. Stable representations extend reasoning beyond unaided memoryOriginal source, plain English guide and key takeaways

CHAP. III.: Of The Extent Of Human Knowledge. Limits of natural knowledge, inquiry, and universal claimsOriginal source, plain English guide and key takeaways

CHAP. IV.: Of The Reality Of Knowledge. Knowledge becomes real when its ideas answer to their intended standardOriginal source, plain English guide and key takeaways

CHAP. IV.: Of The Reality Of Knowledge. Empirical categories must not turn limited descriptions into diminished human statusOriginal source, plain English guide and key takeaways

CHAP. V.: Of Truth In GeneralOriginal source, plain English guide and key takeaways

CHAP. VI.: Of Universal Propositions, Their Truth And Certainty. A universal proposition needs determinate terms and necessary connectionsOriginal source, plain English guide and key takeaways

CHAP. VI.: Of Universal Propositions, Their Truth And Certainty. Substance properties depend on structures and relations we cannot fully inspectOriginal source, plain English guide and key takeaways

CHAP. VI.: Of Universal Propositions, Their Truth And Certainty. A nominal definition cannot predict every property of its membersOriginal source, plain English guide and key takeaways

CHAP. VII.: Of Maxims. Self evidence belongs to immediate comparison, not a privileged list of axiomsOriginal source, plain English guide and key takeaways

CHAP. VII.: Of Maxims. Maxims can organise teaching and end disputes without generating discoveriesOriginal source, plain English guide and key takeaways

CHAP. VII.: Of Maxims. A sound maxim cannot rescue an argument built from shifting termsOriginal source, plain English guide and key takeaways

CHAP. VII.: Of Maxims. A consistent definition can still encode prejudice and exclude real peopleOriginal source, plain English guide and key takeaways

CHAP. VIII.: Of Trifling Propositions. A true proposition teaches only when it reveals a connection not already contained in its termsOriginal source, plain English guide and key takeaways

CHAP. VIII.: Of Trifling Propositions. Coherent reasoning about definitions can remain empty of knowledge about realityOriginal source, plain English guide and key takeaways

CHAP. IX.: Of Our Knowledge Of ExistenceOriginal source, plain English guide and key takeaways

CHAP. X.: Of Our Knowledge Of The Existence Of A God. Locke argues from present existence to an eternal and intelligent sourceOriginal source, plain English guide and key takeaways

CHAP. X.: Of Our Knowledge Of The Existence Of A God. Locke denies that thought can emerge from organised nonthinking matterOriginal source, plain English guide and key takeaways

CHAP. XI.: Of Our Knowledge Of The Existence Of Other Things. Active sensation gives practical knowledge of an external causeOriginal source, plain English guide and key takeaways

CHAP. XI.: Of Our Knowledge Of The Existence Of Other Things. Evidence for existence changes with time, memory, and the reach of sensationOriginal source, plain English guide and key takeaways

CHAP. XII.: Of The Improvement Of Our Knowledge. Methods of inquiry must fit the ideas and evidence of each subjectOriginal source, plain English guide and key takeaways

CHAP. XII.: Of The Improvement Of Our Knowledge. Experiment advances natural inquiry when hypotheses remain answerable to particularsOriginal source, plain English guide and key takeaways

CHAP. XIII.: Some Farther Considerations Concerning Our KnowledgeOriginal source, plain English guide and key takeaways

CHAP. XIV.: Of JudgmentOriginal source, plain English guide and key takeaways

CHAP. XV.: Of ProbabilityOriginal source, plain English guide and key takeaways

CHAP. XVI.: Of The Degrees Of Assent. Remembered judgements need proportionate confidence and a fair route to reconsiderationOriginal source, plain English guide and key takeaways

CHAP. XVI.: Of The Degrees Of Assent. Testimony weakens through unverified transmission while analogy guides cautious conjectureOriginal source, plain English guide and key takeaways

CHAP. XVII.: Of Reason. Reason discovers and orders connections before formal argument can display themOriginal source, plain English guide and key takeaways

CHAP. XVII.: Of Reason. A plain argument map can expose weak links more clearly than formal repetitionOriginal source, plain English guide and key takeaways

CHAP. XVII.: Of Reason. Reason needs discovery tools and fails when its materials are missing or defectiveOriginal source, plain English guide and key takeaways

CHAP. XVII.: Of Reason. Reason should follow evidence rather than authority, ignorance, or an opponent's inconsistencyOriginal source, plain English guide and key takeaways

CHAP. XVIII.: Of Faith And Reason, And Their Distinct Provinces. A claim of revelation cannot override clearer evidence or escape rational authenticationOriginal source, plain English guide and key takeaways

CHAP. XVIII.: Of Faith And Reason, And Their Distinct Provinces. What exceeds reason must still be distinguished from what contradicts itOriginal source, plain English guide and key takeaways

CHAP. XIX.: Of Enthusiasm. Strength of conviction is not evidence that an impulse has divine authorityOriginal source, plain English guide and key takeaways

CHAP. XIX.: Of Enthusiasm. Private certainty requires an independent test of both truth and sourceOriginal source, plain English guide and key takeaways

CHAP. XX.: Of Wrong Assent, Or Errour. Error can arise from unequal access, limited skill, avoidance, or distorted standardsOriginal source, plain English guide and key takeaways

CHAP. XX.: Of Wrong Assent, Or Errour. Inherited principles and protected identities can make contrary evidence appear impossibleOriginal source, plain English guide and key takeaways

CHAP. XX.: Of Wrong Assent, Or Errour. People govern inquiry more readily than they govern the conclusion evidence presentsOriginal source, plain English guide and key takeaways

CHAP. XXI.: Of The Division Of The SciencesOriginal source, plain English guide and key takeaways

Source and edition are always named.

John Locke, 1690. The Ancient Knowledge Club guide is original and kept separate from the source text.