Enlightenment
John Locke
1632–1704
“So that if any one will examine himself concerning his notion of pure substance in general, he will find he has no other idea of it at all, but only a supposition of he knows not what support of such qualities which are capable of producing simple ideas in us.”
John Locke was an English physician and political writer who lived through civil war and restoration. denies innate ideas and traces knowledge to experience. The mind begins as a blank tablet filled by sensation and reflection. The holds that persons already have rights to life, liberty, and property in the state of nature. Government is a trust for their security. When the trust is broken, the people may dissolve the government. Empiricism and liberal constitutionalism still move within these lines.
In the Conversation
56 of the Great Ideas
Ethics
Happiness
Happiness is the greatest pleasure we are capable of, and the pursuit of it is the spring of all action.
Punishment
In nature every person may punish a transgressor of natural law; in civil society that right passes to the magistrate, who punishes to deter, reform, and repair.
Duty
Three sources of duty: God's command, the state's power, and the law of opinion; Locke mediates between Hobbes and the ancients.
Pleasure and Pain
Pleasure and pain are the hinges on which the passions turn; happiness is the utmost pleasure, and misery the utmost pain.
Politics
Liberty
Liberty is freedom under law: the natural right to order one's person and possessions as one sees fit.
Government
Government exists to protect natural rights. When it violates them, the people may revolt.
Law
Legitimate law must conform to natural law and express the consent of the governed.
War and Peace
The state of nature is not war itself, but inevitably lapses into it without civil society.
Democracy
Legitimate government rests on consent, and the majority's power is limited by natural rights.
State
The state is formed by consent to protect natural rights; when it violates those rights, the people may dissolve it.
Wealth
Labor creates property; the invention of money makes unlimited accumulation rational, and government exists to protect what labor has earned.
Revolution
When government acts against the trust placed in it, the people have the right to resist and reconstitute political authority.
Tyranny
Tyranny is the exercise of power beyond right; wherever law ends, tyranny begins.
Family
Conjugal society is a voluntary compact, and parental authority is temporary — held in trust for the child's eventual freedom.
Citizen
The citizen is no subject: political membership rests on consent, and government that violates natural rights forfeits its claim to obedience.
Labor
Labor is the source of all value and the foundation of all rightful property: what a man works on becomes his own.
Slavery
No man can sell himself into slavery; the institution is legitimate only as a continued state of war.
Constitution
Government rests on the consent of the governed; the legislative power is supreme but bounded by natural law and the trust of the people.
Monarchy
Absolute monarchy is inconsistent with civil society and can be no form of civil government at all.
Theology & Metaphysics
Being
Substance is only a supposed 'something we know not what' underlying qualities; the real essence of things lies beyond our knowledge.
Religion
Religious belief cannot be compelled by force; the state has no jurisdiction over the soul, and toleration is the mark of a true church.
Immortality
Personal identity depends on continuity of consciousness, not on the persistence of any substance; the real question is whether the same person survives, not the same soul.
Metaphysics
Metaphysical substance is a 'something I know not what' behind qualities; the discipline overreaches when it claims knowledge beyond experience.
Metaphysics
Form
Real essences are hidden; what we call kinds are nominal essences, abstract ideas we ourselves compose to sort particulars.
Matter
Bodies have primary qualities that really belong to them, and secondary qualities that are powers to produce ideas in us.
Space
Space is a simple idea from sight and touch; we can conceive empty space beyond all bodies.
Relation
Relations form a distinct class of ideas, produced when the mind brings two things together and compares them, yet they depend on real foundations in the things compared.
Same and Other
Personal identity is continuity of consciousness, not sameness of substance; wherever memory reaches, there the self extends.
Quality
Primary qualities (solidity, extension, motion, number) resemble their causes in objects; secondary qualities (color, sound, taste) are powers to produce ideas in us.
Quantity
Our ideas of quantity arise from sensation and reflection; number is the simplest and most universal idea, applicable to everything that exists or can be imagined.
Eternity & Infinity
Epistemology
Knowledge
The mind is a blank slate. All knowledge is built from experience: sensation and reflection.
Mind
The mind begins as a blank tablet; experience, sensation and reflection, writes all its contents.
Experience
No innate ideas; the mind is a blank slate, and all knowledge comes from experience through sensation and reflection.
Will
Freedom belongs to the agent, not to the will; asking 'Is the will free?' is asking the wrong question.
Language
Words stand for ideas in the speaker's mind, not for things directly; the imperfections of language are the source of most philosophical disputes.
Memory and Imagination
The mind stores simple ideas through retention; contemplation keeps ideas in view, memory revives them.
Rhetoric
Rhetoric is an instrument of error; figurative speech belongs to wit, not judgment, and impedes the pursuit of truth.
Opinion
Knowledge is the perception of the agreement of ideas; everything beyond it is probability and opinion, but opinion suffices for the conduct of life and grounds the right of toleration.
Idea
The mind has no innate ideas; all ideas come from experience, through sensation and reflection.
Judgment
Knowledge is the perception of agreement between ideas; judgment operates where demonstration falls short, guided by probability.
Sense
Sensation is one of two channels of experience; it furnishes the mind with simple ideas that reason cannot produce on its own.
Sign and Symbol
Words are signs of ideas in the mind; their meaning is the idea the speaker associates with them, not some essence in things.
Mathematics
Mathematical knowledge is certain because it concerns the agreement and disagreement of our own ideas of number and figure.
Logic & Method
Principle
There are no innate principles; all knowledge, including so-called self-evident truths, derives from experience.
Reasoning
Reasoning discovers the connection between ideas; it enlarges knowledge beyond intuition but depends on careful management of evidence.
Logic
The capacity for reasoning comes from God and nature; formal logic adds little to what the natural use of the understanding already achieves.
Definition
Our definitions are of nominal essences only; real essences — the inner constitutions that produce the observable qualities of things — remain largely unknown to us.
Universal and Particular
General terms correspond to abstract general ideas, which are particular ideas with their individual features removed; these ideas are the work of the understanding, not objects existing outside the mind.
Philosophy & Practical
Life & Nature
Animal
Animals perceive and retain ideas but cannot abstract; the power of abstraction marks the true boundary between beast and human.
Element
We know the nominal essence of substances but not their real inner constitution; the true elements remain hidden from us.
Medicine
Medical knowledge is limited by the body's complexity; the physician must settle for probable knowledge grounded in careful observation.