Get started

WorkGeorge Berkeley

A Treatise Concerning the Principles of Human Knowledge

Berkeley's frontal case that matter does not exist: to be is to be perceived, and behind our ideas lie only other minds and God.

by George Berkeley203 passages held

  • English, the original language, and your language
Sign in or subscribe to discuss this work See it in context
First published
(aged 25)
Original language
English

Report a rights issue

Overview

Everyone agreed the world was made of matter — inert stuff existing outside any mind and throwing off the ideas we perceive. Berkeley denied there was any such thing, and thought that denying it would rescue both common sense and religion from the skeptics. His principle is three words unpacked at length: to be is to be perceived. A thing's existence consists in its being perceived; an idea can resemble nothing but another idea, so the material object supposed to stand behind our sensations is not merely unknown but incoherent — and unnecessary besides, since no one could ever explain how dead matter gives rise to a living perception. What keeps the world steady when no human looks is God, in whose perception all things continuously stand. Berkeley aimed this at Locke and Descartes and believed he was defending the plain man against the philosophers. The plain man was not grateful: readers met the book with incomprehension and filed its author among the purveyors of skeptical paradox, the very charge he had written it to answer. He had promised a Part Two, on spirits and God; the manuscript, he said later, was lost during his travels in Italy, and he never rewrote it. Only Part One exists. Hume and Kant read what there was.

Key concepts

What does 'to be is to be perceived' mean?

It is Berkeley's central principle, esse est percipi: for the ordinary objects of experience, existence just is being perceived. A tree or table is a bundle of sensible ideas — colors, shapes, textures — and apart from some mind perceiving them there is nothing left over for them to be. The slogan denies that things have a further existence as mind-independent matter behind the ideas we actually have.

Why does Berkeley deny that matter exists?

He offers two main reasons. First, an idea can resemble nothing but another idea, so the material object supposed to lie behind our sensations could never be like them, making it incoherent. Second, it is unnecessary: no one can explain how inert, dead matter would produce a living perception, so matter does no explanatory work. Being both unintelligible and idle, it should be dropped.

What is Berkeley's attack on abstract ideas?

In the Introduction Berkeley argues that the mind cannot form genuinely abstract general ideas — a triangle that is no particular triangle, or extension in general. We reason with particular ideas that represent others of their kind. General words mislead philosophers into positing abstract objects, and Berkeley traces belief in inert matter partly to this error, treating an empty abstract term as though it named a real idea.

What role does God play in the system?

God is what keeps the world in being when no human perceives it. Since things exist only as they are perceived, an ever-present divine mind sustains the order and continuity of nature, perceiving all things continuously. God is also the cause of our sensory ideas, which we do not produce ourselves. This lets Berkeley deny matter while preserving a stable, shared, law-governed world.

Why does only Part One of the book survive?

Berkeley promised a second part, on spirits and God, but never published it. He said later that the manuscript was lost during his travels in Italy, and he never rewrote it. So the Principles we have is only Part One — the statement of immaterialism itself. Hume and Kant read what there was, and the book stands as the head-on version of the case Berkeley recast as dialogue three years later.

Themes of the book

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

The attack on abstract ideas

Can the mind form an idea of a triangle that is no particular triangle, of color that is no particular color? Berkeley says no, and blames much of philosophy's confusion on believing it can.

The Principles opens by attacking the doctrine of abstract general ideas — the supposed power to conceive a triangle that is neither scalene nor equilateral, or man in general apart from any particular man. Berkeley argues no such idea can actually be formed; we think with particular ideas that stand in for others, and general words mislead us into imagining general objects behind them. Aimed squarely at Locke, this is the ground-clearing for everything that follows: many of the errors he wants to expose, above all belief in inert matter, arise from mistaking an abstract word for a genuine idea.

  • abstraction
  • language
  • logic
  • geometry
  • arithmetic
  • causation
  • immaterialism

Enter a dialogue

To be is to be perceived

What is it for a thing to exist? Berkeley's answer denies the one thing everyone assumed: there is no mind-independent matter, only ideas and the minds that perceive them.

Berkeley's principle is three words unpacked at length: to be is to be perceived. A thing's existence consists in its being perceived, so the ordinary objects of experience are collections of ideas, not surfaces thrown off by hidden matter. His argument is that an idea can resemble nothing but another idea, which makes the supposed material object behind our sensations not merely unknown but incoherent — and unnecessary besides, since no one could explain how dead matter gives rise to a living perception. He aimed this at Locke and Descartes, convinced he was removing a needless and unintelligible posit.

  • idealism
  • perception
  • existence
  • matter
  • substance
  • materialism
  • ontology
  • metaphysics
  • reality

Enter a dialogue

God, and the defence of common sense

If things exist only in being perceived, what holds the world steady when no one is looking? Berkeley answers with God — and insists he is rescuing common sense, not attacking it.

What keeps the world in being when no human perceives it is God, in whose perception all things continuously stand. This is not a decorative addition but load-bearing: it lets Berkeley deny matter without denying that the world is stable and shared. He believed he was defending the plain man and religion against the skeptics, keeping every ordinary thing exactly as it seems while removing only the philosophers' inert matter. The plain man was not grateful — readers met the book with incomprehension — but Berkeley's aim throughout is to answer skepticism, not to spread it.

  • theology
  • spirit
  • skepticism
  • teleology
  • reality
  • idealism
  • ideas

Enter a dialogue

Within this work

passages held
203
distinct concepts
213
by passages held, corpus-wide
#131

What this book thinks together

Every arc around the wheel is one concept in this book. A ribbon joins two the text reaches for together, and its width is how many of its passages hold both. Strongest: epistemology with perception.
Concept co-occurrence, strongest first 8 concepts, joined by 17 pairings. 79 shared passages in all. 83 weaker pairings reach beyond these concepts and are not drawn.
ConceptPaired conceptShared passages
epistemologyperception8
abstractionperception6
epistemologylanguage6
metaphysicssubstance6
abstractionepistemology5
abstractionlanguage5
abstractionmetaphysics5
causalitymetaphysics5
causalityperception5
perceptionspirit5
causalityspirit4
metaphysicsperception4
spiritsubstance4
epistemologyspirit3
languagemetaphysics3
metaphysicsspirit3
epistemologymetaphysics2

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.

  1. 1709 An Essay Towards a New Theory of Vision

    Written at twenty-four out of the optics Berkeley studied at Trinity College, Dublin, and the least contested of his works — the theory of vision was taken up where his metaphysics was refused.

     EN
  2. 1710 A Treatise Concerning the Principles of Human Knowledge you are here EN
  3. 1713 Three Dialogues Between Hylas and Philonous in Opposition to Sceptics and Atheists

    Berkeley's second attempt at the case of the Principles, put into dialogue to win over the general reader whom the first book had only estranged.

     EN
Sign in or subscribe to discuss this work

— or open another of their works