BERKELEY’S CONCEPTION OF
PHYSICAL OBJECTS – A PROBLEM?
What precisely is the overhead
projector?
Materialist – a material object with
mass, extension, etc. which occupies
space; totally perceiver independent
Berkeley – sensory ideas; dependent
on some perceiver. But whose ideas
and which sensory ideas?
a. The particular ideas I am now
experiencing when I see the
projector?
b. The particular ideas you are
experiencing when you see the
projector?
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c. God’s sensory ideas of the
projector?
d. Something else entirely?
Problem regarding a. – c. – Do we in
fact perceive the same overhead
projector?
It would seem not. Why? Because my
sensory ideas, though perhaps similar
to yours (and to God’s) are not the
same as mine.
Or are they?
Two senses of “same” or “identical”
1.
2.
Numerical sameness (identity)
Qualitative sameness (identity)
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E.g. Tom and Sally each owns a Honda
Civic
1. Tom and Sally do not own the
same car – numerical sameness
2. Tom and Sally do own the same
car – qualitative sameness
3. You and I do not experience the
same sensory ideas of the overhead
projector – numerical sameness.
But
4. You and I do experience the
same sensory ideas of the overhead
projector – qualitative sameness
(Complication… Leibniz and “point
of view” – in fact sensory ideas not
qualitative the same, just “similar”.
Let’s ignore.)
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So in one sense – qualitative
sameness – we can perhaps be said
to have the same sensory ideas (of
the overhead projector).
But puzzles still remain.
Again: What exactly is the overhead
projector?
Ideas in a mind. But whose mind?
God’s? But those ideas never exist in
my mind – though qualitatively
identical (or similar) ones do – and
so I cannot perceive them. So I can
never perceive the overhead
projector.
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If I am indeed able to perceive the
overhead projector, and it consists of
ideas in a mind, then it would seem
that it must consist of ideas in my
mind
Problems with this view?
1. Each of us can never perceive the
same overhead projector
2. The overhead projector is not
perceiver independent in the way
Berkeley needs. The overhead
projector I perceive is dependent
on me for its existence – same for
you and “your” overhead
projector.
3. Berkeley unable to account for
features 1 – 6.
4. Berkeley’s critique of the
materialist thesis fails
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5. Berkeley’s Irrelevance thesis
remains unsubstantiated.
An Alternative?
If overhead projector does not consist
in any particular ideas existing in any
particular mind, then what could it be?
Two options(?)
a. the “intensional object” which
“appears” in each subset of
sensory ideas experienced by
anyone who is currently
perceiving the overhead
projector.
In this case, the overhead projector,
X, exists within each of the
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perceptions of everyone who
currently has a perception of X
It is the “object” or “content” of all
those subsets of ideas each of which
consists in a perception of the
overhead projector.
Problem?
Does the overhead projector become
an “abstract object” – an object which
is abstracted from all the qualitatively
identical or “similar” sensory ideas of
those who are perceiving the
projector?
If so, then we have a serious problem
since Berkeley rejects the possibility of
abstraction.
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b. The projector is the entire
collection of particular sensory
ideas experienced by anyone who
is currently perceiving it
(including you, me and God)
Problem?
I never experience more than a tiny
fraction of the ideas which constitute
the overhead projector.
So do I actually perceive the overhead
projector?
Perhaps so. Perhaps to perceive X just
is to perceive some subset of the
complete set of particular ideas which
constitute X.
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AND X continues to exist so long as at
least one mind is experiencing one of
these subsets
Moral of the Story?
1. Berkeley’s theory of physical
objects raises serious
metaphysical difficulties which
stand in need of resolution.
2. Berkeley’s alternative to the
materialist’s “black box”
explanation of the manner and
production of our sensory ideas is
underdeveloped.
3. Berkeley’s critique of the
materialist’s theory – premised as
it is on the idea that Berkeley’s
explanation is far better because
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it raises far fewer questions – is
problematic.
4. Berkeley has failed to
substantiate The Irrelevance
Thesis.
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