Of the Conduct of the Understanding

A chapter that outgrew the book it was written for: Locke's unfinished manual on reasoning well.

English, the original language, and your language

First published: 1706(published posthumously)
Original language: English

Overview

The fourth edition of Locke's Essay, printed in 1700, carried two new chapters, one on the association of ideas and one on enthusiasm, the claim to be directly inspired by God. A third had been planned and is missing. In April 1697 Locke told his Dublin friend William Molyneux that he was writing an addition on the conduct of the understanding. It kept growing, it was never finished, and it stayed among his papers until Peter King, a relative and one of his executors, printed it in 1706, two years after his death. The Essay had described how the mind gets its ideas; Of the Conduct of the Understanding is about how people misuse the mind they have. Locke starts from a complaint against the logic taught in the universities, which drilled students in the forms of argument and, in his view, left them no better at judging a real question. Reasoning, he argues, is a habit built by practice, the way a dancer's or a craftsman's skill is built. Most bad thinking has one of three sources: taking opinions on trust from parents, neighbours or party; letting interest and passion stand where reasons should; and judging from a partial view, as people do who read one kind of book and keep one kind of company. His remedies are plain. Study mathematics to learn what a proof is like, hold each opinion with no more confidence than its evidence gives, and go looking for the strongest case against it. The text is a draft, repetitive in places and without an ending. It was first issued as a book on its own in 1762.

Key concepts

What does “conduct of the understanding” mean?

It means the management of one’s own mind: how a person directs attention, forms opinions and checks them. Locke treats the understanding as something we are responsible for running, the way we are responsible for our actions. The work is a list of the habits that run it badly and the habits that could run it well, written for adults who must retrain themselves.

What is “bottoming”?

Bottoming is tracing an opinion down to the foundation it rests on. Locke observes that most disagreements are argued at the surface, over consequences, while the real difference lies in some principle further down that neither side has examined. To bottom a question is to find that principle and ask whether it is true.

What does Locke mean by “principles”?

Principles are the starting points a person reasons from without questioning them. Locke’s worry is that most people’s principles were never chosen: they were absorbed in childhood from family, church or country and now feel self-evident. Someone who reasons flawlessly from a false principle only goes wrong more confidently. He asks that each be examined once, as carefully as any other claim.

What are “natural parts”?

Natural parts are the abilities a person is born with: quickness, memory, a head for figures. Locke grants that people differ in them, and then argues that the difference matters far less than is assumed. Set side by side people of equal parts, one who has ranged widely and one who has not, and the gap between them looks like a gap in talent. It is a gap in exercise.

How does Locke understand prejudice?

Prejudice is an opinion held before, or without, weighing the evidence for it. Locke notes that everyone complains of it in others and nobody admits it in himself. His test is practical: a person who cannot calmly hear his opinion questioned, or who will not look at the arguments against it, is prejudiced, whatever the opinion happens to be and even if it is true.

Themes of the book

What this book returns to, gathered into themes and ordered by how much of the text each one occupies.

Reason Is Built by Practice

Is good reasoning a gift some people are born with, or a skill like any other? If it is a skill, the logic of the schools has been teaching the rules of a game nobody learned to play.

We are born with faculties capable of almost anything, Locke writes, but only their exercise gives us ability. A ploughman’s limbs are as good as a dancing-master’s; years of use make the difference, and so it is with minds. The logic taught in the universities supplies the forms of argument and no practice in judging a real question. He recommends mathematics, to learn what a chain of proof is like and to carry that standard into other subjects. Reading alone will not do it either: books give materials, and only thinking them over makes them one’s own. Much of what passes for natural dullness is want of use.

reasoning
practice
habit
education
mathematics
learning
intellectual development
method
understanding
reading

Enter a dialogue

How a Mind Misleads Itself

Why do intelligent people reason badly about the things they care most about? Locke answers that the fault lies less in the reasoning than in what they never let into view.

Three kinds of people go wrong, by his count: those who take their opinions from parents, neighbours or party; those who put passion and interest where reasons should be; and those who reason honestly from a partial view. The third is the common case. People read one sort of book and keep one sort of company, like the islanders who believed themselves the only people in the world. The remedy he calls indifferency: to care more that an opinion be true than that it be one’s own, to give it no more assent than its evidence warrants, and to hear the other side at its strongest.

bias
prejudice
self-deception
impartiality
evidence
belief
critical thinking
truth
intellectual humility
testimony
judgment
intellectual freedom

Enter a dialogue

Within this work

passages held: 122
distinct concepts: 160
by passages held, corpus-wide: #466

What this book thinks together

The wheel takes this book’s leading concepts and shows how often they come up together. The wider the band between two, the more of its passages speak of both. Among them, most often together: “education” and “reasoning”.

Concept co-occurrence, strongest first 8 concepts, joined by 26 pairings. 85 pairings reach beyond these concepts and are not drawn.
Concept	Paired concept	Shared passages
education	reasoning	16
knowledge	reasoning	10
education	knowledge	7
belief	evidence	4
bias	truth	4
belief	truth	3
bias	evidence	3
bias	reasoning	3
critical thinking	education	3
critical thinking	knowledge	3
evidence	knowledge	3
evidence	reasoning	3
evidence	truth	3
bias	knowledge	2
critical thinking	truth	2
belief	bias	1
belief	critical thinking	1
belief	education	1
belief	reasoning	1
bias	critical thinking	1
bias	education	1
critical thinking	evidence	1
critical thinking	reasoning	1
education	truth	1
knowledge	truth	1
reasoning	truth	1

Works held

The author's work in order, this book marked in place. Your-language title first, the original beneath it where the two differ; side chips show which full texts are held.

1689 A Letter Concerning Toleration (Epistola de Tolerantia)
The one statement of his case for religious freedom that Locke made briefly and to a friend. Everything else he printed on the subject defends this text against one of its critics, Jonas Proast.
EN
1689 An Essay Concerning Human Understanding
The book Locke's reputation rests on, and the one major work of 1689 that he signed. His quarrel with Bishop Stillingfleet, the unfinished Conduct of the Understanding and the letters to William Molyneux all grow out of it.
EN
1689 Two Treatises of Government
Two parts of a longer manuscript whose middle was lost before printing, as Locke's preface says. The book is his political theory, and it shares a year and a purpose with A Letter Concerning Toleration: each sets a limit on what a ruler may do.
EN
1690 Further Letters Concerning Toleration
A sequel in three parts to A Letter Concerning Toleration: Locke's second and third letters and the fragment of a fourth, each a reply to the Oxford chaplain Jonas Proast. The third is where he tests his case hardest.
EN
1693 Some Thoughts Concerning Education
Written for the household of his friend Edward Clarke and enlarged by Locke through several editions. It is his book of practical advice on raising a child, and it applies the Essay's view that the mind is formed by what it meets.
EN
1695 The Reasonableness of Christianity
His main work on religion, and the opening of the study of Scripture that occupied his last years. He defended it twice against John Edwards, a Cambridge Calvinist, and kept his name off all three books while he lived.
EN
1696 Several Papers Relating to Money, Interest and Trade
Advice written for ministers and for Parliament during the currency crisis of the 1690s, and gathered under Locke's name in 1696. The account of money behind it is sketched in the chapter on property in the Two Treatises.
EN
1697 Letters to the Bishop of Worcester
Locke's own commentary on the Essay, written under attack: three replies to Edward Stillingfleet, issued as separate pamphlets between 1697 and 1699, with a short answer to a second critic, Thomas Burnet, Master of the Charterhouse.
EN
1706 Of the Conduct of the Understanding you are here EN
1706 Posthumous Works
From the volume of unpublished papers that Locke's executors issued in 1706: a critique of Malebranche from the 1690s and a short discourse on miracles from 1702. Both extend arguments begun in the Essay.
EN
1708 Some Familiar Letters between Mr. Locke and Several of His Friends
Letters to the Molyneux brothers of Dublin — Locke's side of the correspondence — taken from a volume his publishers issued in 1708. It is the closest view of him at work on the later editions of the Essay.
EN
1720 A Collection of Several Pieces
The Carolina constitution of 1669 predates the Two Treatises by ten years or more, and the two are often set against each other. Pierre Des Maizeaux published it in 1720 together with shorter pieces left out of the collected works.
EN

— or open another of their works