John Locke was an influential English philosopher and social contract theorist. He developed an alternative to the Hobbesian state of nature and discussed a government could only be good if it received the consent of the governed and protected the natural rights of life, liberty, and estate. If such a consent was not achieved, Locke argued in favour of a right of rebellion.

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• If any man err from the right way, it is his own misfortune, no injury to thee; nor therefore art thou to punish him in the things of this life because thou supposest he will be miserable in that which is to come.
  • A Letter Concerning Toleration (1689)

• To love truth for truth's sake is the principal part of human perfection in this world, and the seed-plot of all other virtues.
  • Letter to Anthony Collins (30 October 1703)

• Stop Traveller! Near this place lieth John Locke. If you ask what kind of a man he was, he answers that he lived content with his own small fortune. Bred a scholar, he made his learning subservient only to the cause of truth. This thou will learn from his writings, which will show thee everything else concerning him, with greater truth, than the suspect praises of an epitaph. His virtues, indeed, if he had any, were too little for him to propose as matter of praise to himself, or as an example to thee. Let his vices be buried together. As to an example of manners, if you seek that, you have it in the Gospels; of vices, to wish you have one nowhere; if mortality, certainly, (and may it profit thee), thou hast one here and everywhere.
  • Epitaph, as translated from the Latin.

• This is that which I think great readers are apt to be mistaken in; those who have read of everything, are thought to understand everything too; but it is not always so. Reading furnishes the mind only with materials of knowledge; it is thinking that makes what we read ours. We are of the ruminating kind, and it is not enough to cram ourselves with a great load of collections ; unless we chew them over again, they will not give us strength and nourishment.
  • As quoted in "Hand Book : Caution and Counsels" in The Common School Journal Vol. 5, No. 24 (15 December 1843) by Horace Mann, p. 371

Essay Concerning Human Understanding (1689)

• New opinions are always suspected, and usually opposed, without any other reason but because they are not already common.
  • Dedicatory epistle

• There cannot any one moral Rule be propos'd, whereof a Man may not justly demand a Reason.
  • Book I, Ch. 3, sec. 4

• No man's knowledge here can go beyond his experience.
  • Book II, Ch. 1, sec. 19

• Since sounds have no natural connection with our ideas ... the doubtfulness and uncertainty of their signification ... has its cause more in the ideas they stand for than in any incapacity there is in one sound more than another to signify any idea.
  • Book III, Ch. 9, sec. 4

• He that uses his words loosely and unsteadily will either not be minded or not understood.
  • Book III, Ch. 10, sec. 31

• I doubt not, but from self-evident Propositions, by necessary Consequences, as incontestable as those in Mathematics, the measures of right and wrong might be made out.
  • Book IV, Ch. 3, sec. 18

• False and doubtful positions, relied upon as unquestionable maxims, keep those who build on them in the dark from truth. Such are usually the prejudices imbibed from education, party, reverence, fashion interest, et cetera.
  • Book IV, Ch. 7

• It is one thing to show a man that he is in error, and another to put him in possession of the truth.
  • Book IV, Ch. 7, sec. 11

• For where is the man that has incontestable evidence of the truth of all that he holds, or of the falsehood of all he condemns; or can say that he has examined to the bottom all his own, or other men's opinions? The necessity of believing without knowledge, nay often upon very slight grounds, in this fleeting state of action and blindness we are in, should make us more busy and careful to inform ourselves than constrain others. At least, those who have not thoroughly examined to the bottom all their own tenets, must confess they are unfit to prescribe to others; and are unreasonable in imposing that as truth on other men's belief, which they themselves have not searched into, nor weighed the arguments of probability, on which they should receive or reject it. Those who have fairly and truly examined, and are thereby got past doubt in all the doctrines they profess and govern themselves by, would have a juster pretence to require others to follow them: but these are so few in number, and find so little reason to be magisterial in their opinions, that nothing insolent and imperious is to be expected from them: and there is reason to think, that, if men were better instructed themselves, they would be less imposing on others.
  • Book IV, Ch. 16, sec. 4

• Religion, which should most distinguish us from the beasts, and ought most particularly elevate us, as rational creatures, above brutes, is that wherein men often appear most irrational, and more senseless than beasts.
  • Book IV, Ch. 18

• He that would seriously set upon the search of truth, ought in the first place to prepare his mind with a love of it. For he that loves it not, will not take much pains to get it; nor be much concerned when he misses it. There is nobody in the commonwealth of learning who does not profess himself a lover of truth: and there is not a rational creature that would not take it amiss to be thought otherwise of. And yet, for all this, one may truly say, that there are very few lovers of truth, for truth's sake, even amongst those who persuade themselves that they are so. How a man may know whether he be so in earnest, is worth inquiry: and I think there is one unerring mark of it, viz. The not entertaining any proposition with greater assurance than the proofs it is built upon will warrant. Whoever goes beyond this measure of assent, it is plain receives not the truth in the love of it; loves not truth for truth's sake, but for some other bye-end.
  • Book IV, Ch. 19 : Of Enthusiasm (Chapter added in the fourth edition).
  • Variant paraphrase, sometimes cited as a direct quote: One unerring mark of the love of truth is not entertaining any proposition with greater assurance than the proofs it is built upon will warrant.
    • As paraphrased in Peter's Quotations : Ideas for our Time (1979) by Laurence J. Peter, p. 500; also in The Demon-Haunted World : Science as a Candle in the Dark (1994) by Carl Sagan, p. 64

• All men are liable to error; and most men are, in many points, by passion or interest, under temptation to it.
  • Book IV, Ch. 20, sec. 17

Two Treatises of Government (1689)

• The imagination is always restless and suggests a variety of thoughts, and the will, reason being laid aside, is ready for every extravagant project; and in this State, he that goes farthest out of the way, is thought fittest to lead, and is sure of most followers: And when Fashion hath once Established, what Folly or craft began, Custom makes it Sacred, and 'twill be thought impudence or madness, to contradict or question it. He that will impartially survey the Nations of the World, will find so much of the Governments, Religion, and Manners brought in and continued amongst them by these means, that they will have but little Reverence for the Practices which are in use and credit amongst Men.
  • First Treatise of Government

• If man in the state of nature be so free, as has been said; if he be absolute lord of his own person and possessions, equal to the greatest, and subject to no body, why will he part with his freedom?
  • Second Treatise of Government, Ch. IX, sec. 123

• The end of Law is not to abolish or restrain, but to preserve and enlarge Freedom.
  • Second Treatise of Government, page 234, Of Civil Governmenthttp://www.archive.org/stream/twotreatisesofg00lockuoft/twotreatisesofg00lockuoft_djvu.txt

• Wherever Law ends, Tyranny begins.
  • Second Treatise of Government, Sec. 202

• To understand political power aright, and derive from it its original, we must consider what estate all men are naturally in, and that is, a state of perfect freedom to order their actions, and dispose of their possessions and persons as they think fit, within the bounds of the law of Nature, without asking leave or depending upon the will of any other man.
  • Second Treatise of Government, Ch. II, sec. 4

• The state of nature has a law of nature to govern it, which obliges every one: and reason, which is that law, teaches all mankind, who will but consult it, that being all equal and independent, no one ought to harm another in his life, health, liberty, or possessions.
  • Second Treatise of Government, Ch. II, sec. 6

• Freedom of Men under Government is, to have a standing Rule to live by, common to every one of that Society, and made by the Legislative Power erected in it; a Liberty to follow my own Will in all things, where the Rule prescribes not; and not to be subject to the inconstant, uncertain, unknown, Arbitrary Will of another Man: as Freedom of Nature is, to be under no other restraint but the Law of Nature.
  • Second Treatise of Civil Government, Ch. IV, sec. 22

• A criminal who, having renounced reason ... hath, by the unjust violence and slaughter he hath committed upon one, declared war against all mankind, and therefore may be destroyed as a lion or tyger, one of those wild savage beasts with whom men can have no society nor security. And upon this is grounded the great law of Nature, "Whoso sheddeth man's blood, by man shall his blood be shed."
  • Second Treatise of Civil Government

• And because it may be too great a temptation to human frailty, apt to grasp at power, for the same persons, who have the power of making laws, to have also in their hands the power to execute them, whereby they may exempt themselves from obedience to the laws they make, and suit the law, both in its making, and execution, to their own private advantage
  • Second Treatise of Civil Government, Ch. XII, sec. 143

• Whensoever therefore the legislative shall transgress this fundamental rule of society; and either by ambition, fear, folly or corruption, endeavour to grasp themselves, or put into the hands of any other, an absolute power over the lives, liberties, and estates of the people; by this breach of trust they forfeit the power the people had put into their hands for quite contrary ends, and it devolves to the people, who have a right to resume their original liberty, and, by the establishment of a new legislative, (such as they shall think fit) provide for their own safety and security, which is the end for which they are in society.
  • Second Treatise of Civil Government, Ch. XIV, sec. 222

• As usurpation is the exercise of power which another has a right to, so tyranny is the exercise of power beyond right, which nobody can have a right to.
  • Second Treatise of Government, Ch. XVIII, sec. 199

Some Thoughts Concerning Education (1693)

• A sound mind in a sound body, is a short but full description of a happy state in this world.
  • Sec. 1

• Thus parents, by humouring and cockering them when little, corrupt the principles of nature in their children, and wonder afterwards to taste the bitter waters, when they themselves have poison’d the fountain.
  • Sec. 35

• Good and evil, reward and punishment, are the only motives to a rational creature: these are the spur and reins whereby all mankind are set on work, and guided.
  • Sec. 54

• Virtue is harder to be got than knowledge of the world; and, if lost in a young man, is seldom recovered.
  • Sec. 64

• He that will have his son have a respect for him and his orders, must himself have a great reverence for his son.
  • Sec. 65

• The only fence against the world is a thorough knowledge of it.
  • Sec. 88

The Reasonableness of Christianity (1695)

The Reasonableness of Christianity, as Delivered in the Scriptures (1695)

• The greatest part of mankind want leisure or capacity for demonstration, nor can carry a train of proofs, which in that way they must always depend upon for conviction, and cannot be required to assent to till they see the demonstration. Wherever they stick, the teachers are always put upon proof, and must clear the doubt by a thread of coherent deductions from the first principle, how long or how intricate soever that be. And you may as soon hope to leave all the day labourers and tradesmen, the spinsters and dairy-maids, perfect mathematicians, as to have them perfect in ethics this way: having plain commands is the sure and only course to bring them to obedience and practice: the greatest part cannot know, and therefore they must believe. And I ask, whether one coming from heaven in the power of God, in full and clear evidence and demonstration of miracles, giving plain and direct rules of morality and obedience, be not likelier to enlighten the bulk of mankind, and set them right in their duties, and bring them to do them, than by reasoning with them from general notions and principles of human reason?
  • § 243

Misattributed

• That which is static and repetitive is boring. That which is dynamic and random is confusing. In between lies art.
  • This statement has been attributed to John A. Locke, but John Locke did not have a middle name. The words "dynamic," "boring" and "repetitive," found in this quote, were not yet in use in Locke's time. See The Online Etymology Dictionary http://www.etymonline.com/abbr.php John A. Locke is listed on one site as having lived from 1899 to 1961; no more information about him was available.

• The people cannot delegate to government the power to do anything which would be unlawful for them to do themselves.
  • This might be a paraphrase of some of Locke's expressions or ideas, but the earliest publication of the statement in this form seems to be one made in Oversight Hearing on the Columbia River Gorge National Scenic Area Act (1997).

Quotes about Locke

• "Reason" said Locke, "must be our last our last judge and guide in everything". In The Reasonableness of Christianity he wrote that "the day labourers and tradesmen, the spinsters and dairy maids" must be told what to think. "The greatest part cannot know, and therefore they must believe." But at least Locke did not intend that priests should do the telling; that was for God himself.
  • Christopher Hill, in The Century of Revolution, 1603-1714 (2001), telling people what to think and believe of Locke.