Berkeley’s idealism
Idealism is a direct theory of perception where the immediate objects of perception are minddependent objects. It is therefore an antirealist theory: what is real depends upon the mind.
In other words: all that exists are minds and their ideas. Physical objects are no more than a
collection of sensations appearing in our minds. Therefore all objects of perception are minddependent.
Bishop Berkeley (1685-1753)
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Bishop of Cloyne, in Ireland.
2nd of the 3 great British Empiricists (after Locke and before Hume). Empiricism – position
which holds that our beliefs and knowledge, must be based on experience.
Wanted to save Locke’s empiricism from the threat of materialism (the view that everything,
including mental/spiritual entities can be given a material explanation) and atheism.
Berkeley rejects the existence of physical objects in an external world independent of us. He claimed
that the ordinary objects of perception – tables, chairs, trees etc. – are all mind-dependent. He
claimed that all objects must be perceived in order to exist. Hence his famous slogan: esse est percipi
(aut percipere) – to be is to be perceived (or to perceive). The only things that exist are minds (that
perceive) and what minds perceive.
However Berkeley did not intend to deny the existence of what we normally think of as physical
objects, but rather he denies that physical objects have an existence independent of our perception.
For example: we can perceive a red rose or a plate filled high of food but Berkeley argues that the
plate of food or rose do not have an existence independent of our perception.
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Berkeley is not saying that we imagine the world around us i.e. perception is a kind
of imagining.
Using Locke’s argument –we cannot choose what we are going to perceive next –
Berkeley is able to remove idealism from the criticism that our perception is simply
our imagination.
Rather, Berkeley argues against IDR’s belief that there is something behind the veil
of perception, some ‘matter’ that exists independently of our perception and results
in stating that an object is a cluster of ideas or sense impressions.
In short:
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Berkeley believed in Idealism because he believed:
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That primary and secondary qualities exist only in our minds, and:
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That the ordinary objects of perception (chairs, tables etc) are just ‘bundles’ of their
primary and secondary qualities.
In order to understand the last section, we need to look at Berkeley’s attack on the
primary/secondary quality distinction.
Berkeley’s attack on the primary/secondary quality distinction
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Berkeley argues that the ordinary objects of perception are nothing more than a ‘bundle’ of
their primary and secondary qualities.
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Against Locke, and the rationalists: he denies that there is an underlying ‘substance’ which
has these qualities, and which exists independently of them. (Rationalism = knowledge is
innate or gained by reason rather from sense experience.)
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In support of this position he points out that the only things we experience, when we
observe things, are their primary and secondary qualities. For example of an apple: I cannot
perceive an apple without its secondary qualities i.e. taste, touch, smell etc.
In simpler terms:
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Berkeley argues that if an object can only be conceived with both primary & secondary
qualities then our ideas of secondary qualities are inseparable from the primary.  if we
accept that our perceptions of secondary qualities exist only in the mind, we must accept
too that our perceptions of primary qualities must be in the mind.
THEREFORE:
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We don’t experience an underlying substance which exists independently of these qualities
– so, if empiricism is right, then we can’t even form an idea of such a substance.
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Thus there cannot be any ‘matter’ hiding behind the veil of perception and so there cannot
be an external real world.
Berkeley’s argument that physical objects are just bundles of primary and secondary qualities:
R1.
When we experience an object, the only thing we experience is its primary and secondary
qualities.
R2.
We do not experience an underlying substance in addition to these qualities.
R3.
If we do not experience an underlying substance, then we cannot form an idea of such a
substance.
C.
So we cannot conceive of physical objects that consist of an underlying substance as well as
their primary and secondary qualities.
This attack can be found within Berkeley’s Three Dialogues between Hylas and Philonous.
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Berkeley, in the character of Philonous, begins by arguing that ‘sensible things’ (whatever is
perceived by the senses) must be whatever is perceived immediately by the senses.
If the causes of these perceptions are not immediately perceived, then we must infer them.
As this is an inference, we cannot say that the ‘cause’ (i.e. what the IDR calls matter) of our
perceptions are themselves being perceived when we perceive the object.
Philonous then argues that what we are immediately aware of and perceive are the qualities
of things. He then goes onto ask whether any of these qualities exist independently of being
perceived.
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Hylas (a realist) begins from the viewpoint of a DR: whatever we perceive exists
independently of our minds i.e. The cold we feel as we touch ice exists in the object.
However, Philonous points out that intense cold or indeed heat, sound, light etc can be
experienced as pain, but pain does not exist in the object!
Philonous is making the point that if we say these secondary qualities are in the object, then,
ultimately one has to say that the object (i.e. ice) also has the quality of pain.
Hylas responds that the cold (or heat) isn’t itself pain, but it instead causes pain.
Philonous objects stating that we simply feel one unified sensation of painful heat.
However, can we not object to Philonous? Surely we can distinguish between the sensation of cold
and then the subsequent feeling of pain?
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Berkeley moves on to use Locke’s example of placing a hot and a cold hand in a bowl of
tepid water. He draws on the argument from perceptual variation to help explain: for the
hot hand the water feels hot and for the cold hand the water feels cold. However, the water
cannot be both hot and cold!
This leads Hylas to be persuaded that secondary qualities are mind-dependent moving him
into the realm of IDR.
However, Philonous attempts to show (again using the argument from perceptual variation)
that primary qualities are mind-dependent too:
Berkeley’s argument that primary qualities exist only in the mind
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R1.
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R2.
If a property varies with the perspective of the perceiver, it must exist only in the
mind of that perceiver.
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C. So primary qualities exist only in the mind of the perceiver.
Primary qualities vary with the perspective of the perceiver.
(See also your annotated notes from class, annotated handout from Berkeley’s dialogue and pp3739 in Hayward, Jones & Cardinal)
Berkeley’s Master Argument
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Try to conceive of a tree which exists outside of any mind – a tree which no one has any
awareness of.
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In attempting to establish this tree, you may think of the idea of a tree hidden in a forest
somewhere no one has ever been.
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But by doing this, you are constructing the idea in your mind! (To imagine the tree falling
unobserved is implicitly to imagine its being observed!)
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Since any supposed thought of an object outside any mind can only take place in someone’s
mind, the idea of a mind-independent object is contradictory.
Berkeley uses this argument to reinforce his point that to be is simply to be perceived.
Berkeley uses the Mind of God to explain how we are able to perceive what we do without mindindependent physical objects:
R1: The immediate objects of perception are ideas.
R2: We have experience of ideas being produced by minds.
R3: We have no experience of ideas being produced by physical objects.
IC1: So we should say that the ideas we experience are produced by a mind.
R4: Our mind is not powerful enough to produce all of the ideas that we experience.
IC2: So the ideas we experience are produced by a mind which is much more powerful than our own.
R5: The only mind that could realistically produce these ideas is the mind of God.
C: So the ideas we experience are produced by the mind of God.
However, Hylas argues ‘to be perceived is one thing and to exist is another.’ If we accept R1 it makes
logical sense that the Mind of God produces these ideas. Yet, Berkeley’s above argument seems
counter-intuitive: if things cannot exist when we are not perceiving them (according to idealism),
then when they are not being perceived, they cease exist.
The limerick by Ronald Knox - God in the Quad – sums up this objection and Berkeley’s reply:
There was a young man who said, "God
Must think it exceedingly odd
If he finds that this tree
Continues to be
When there's no one about in the Quad."
REPLY
Dear Sir:
Your astonishment's odd:
I am always about in the Quad.
And that's why the tree
Will continue to be,
Since observed by
Yours faithfully,
GOD.
Berkeley draws on the concept of God’s Mind being eternal to explain away the dilemma. The
inaccuracy also lies in the suggestion that God observes the tree. However, given the eternal nature
of the Mind of God, Berkeley argues that God does not perceive the tree but that the tree (which is a
bundle of ideas) ‘is comprehended by and exists in the mind of God.’ God doesn’t observe the tree as
it is not external to God’s Mind.
3.1 It leads to solipsism (philosophical idea that only one's own mind is sure to exist).
Solipsism is the view that only oneself, one’s mind, exists. Berkeley’s Idealism begins with the claim
that everything I perceive is mind-dependent as all I perceive are ideas. However, this leads to the
conclusion that all that exists is my own experience. This individual experience gives me no reason to
suggest that anything apart from my experience exists. In other words: if all I experience are ideas,
what reason do I have to think that other minds exist? Furthermore, what reason can I give that
minds exist? After all I do not perceive minds, but ideas.
Berkeley doesn’t explicitly address this issue in the dialogue but he addresses it in various places:
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The mind is that which (actively) perceives, thinks and wills, while ideas are passive.
I am aware of myself as capable of this activity.
Therefore, I am not my ideas, but a mind.
Being a mind myself, I have a ‘notion’ of what a mind is.
Therefore, it is possible that other minds exist.
My perceptions don’t originate in my mind.
Therefore, they are caused by some other mind.
The complexity, regularity of my experience indicates that this mind is God.
(taken from Lacewing p.70)
1.2 It does not give an adequate account of illusions and hallucinations.
An initial difficulty with idealism is that it seems unable to explain the distinction between
perceptual error (i.e. something that is not what it should be) and veridical perception. If the whole
of reality is in the mind, as the idealist seems to be arguing, then there would appear to be no
difference between seeing something as it really is, and being mistaken (perceptual error); or in
other words: between hallucinating and actually seeing something.
Key phrase:
Veridical perception – perception that accurately represents the world.
How then does the idealist make sense of perceptual error? It boils down to the idealist asking
themselves the question: how well does this experience fit with my past experiences? Therefore for
the idealist to accept anything to be real or veridical in must fit well with regularities displayed in our
past experience; anything that does not ‘fit well’ may be regarded as a hallucination or illusion.
(See Lacewing p.66 for more on illusions and language)
1.3 It cannot secure objective space and time.
According to Berkeley, physical objects are ideas. Therefore there cannot be a gap in time nor space
between appearance and reality. Thus the physical objects I experience must exist in exactly the
same time and space that I experience. However, in the dialogues Hylas objects that if you and
another person look at the same tree, the idea that exists in my mind is numerically different from
the idea that exists in the other person’s mind. Berkeley responds:
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The concept of ‘exactly resembling’ is used. Berkeley argues that the tree you see is
qualitatively identical (i.e. same type of thing e.g. breed of dogs) to the tree the other person
sees. However, this response seems to echo that of realism – you and I can look at one and
the same tree – and so a second response is needed.
Idealism can argue that both people perceive the copy of the tree in God’s Mind. Therefore
we perceive exactly the same thing.
Now in relation to objective space and time, Berkeley argues that we can secure this as they are
eternal in the Mind of God. For Berkeley’s account of science, objective space and time are
regularities in relations between what we experience and these relations and regularities are
part of the Mind of God.
(See p. 46 in Cardinal for further critique of Berkeley’s response).
1.4 Whether God can be used to play the role He does.
Criticism/critique of Berkeley’s use of God:
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No independent reason to suppose that there is a God or if there is that God plays the role
Berkeley gives him.
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Goes against Berkeley’s principle that we cannot conceive of anything beyond the mind.
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If all we perceive is sense data it is impossible to have a coherent idea of God – we’ve never
perceived God before!
Responses to the criticism of Berkeley using God to uphold his Idealism
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The cause of our perceptions is a mind, because we can only conceive of minds being active.
For example: I can know other minds exist as people respond to and refer to the language I
use. Therefore communication is possible.
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What I perceive is a copy of the idea in God’s mind.
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The only way to explain the orderly appearance of sense data/perception is by presupposing
the existence of some intelligence producing them. i.e. only an intelligent being or designer
could have created the universe so that the law of gravity works to ensure we do not fall off
the planet!