PHIL 151 History of Modern Philosophy

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PHIL 151 History of Modern Philosophy

• Dr. Martin Godwyn
• Fall 2008
• WEEK 6 Berkeleys Idealism

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George Berkeleys Idealism

• George Berkeley (1685-1753) came after Locke and
  slightly before Hume. He developed a radical
  empiricist solution to the veil of perception
  problems and the mind-body problem
• Rather than postulate an external world of
  matter that (somehow!) causes our perceptions,
  Berkeley argued that to say that something exists
  at all is always to say nothing more than that
  there is an idea in a mind.

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Idealism

• This view is called idealism more specifically,
  subjective idealism.
• As Berkeley famously put it
• Esse est percipi to be is to be perceived.
• The word idealism gets used in other ways today
  but here it simply refers to a theory based on
  the claim that ideas (plus the minds that have
  them) are the fundamental stuff out of which
  the universe is made.

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Idealism is not skepticism

• The intent of idealism is to turn the tables on
  the veil of perception problem facing
  empiricists. We cannot know an external world
  outside our minds because the very idea of an
  external world beyond our minds is absurd.
• Idealism is not skepticism the central point of
  Berkeleyan idealism is to argue that it is silly
  to suppose that there is anything more to be
  known than ones ideas. Hence Berkeley is
  anti-skeptical. We can know the world perfectly
  well inasmuch as we can know our ideas.

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Idealism is not anti-realist

• A common misconception is that idealism denies
  the reality of chairs, planets, etc. Not so
  what it denies is the existence of a
  mind-independent reality.
• Berkeley argues that chairs, planets, etc. really
  do exist. They are as real as real can be. His
  central point is that all that it is for such
  things to exist is for them to be an idea in a
  mind, and there really are such ideas in minds.

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Idealism is not solipsism

• Solipsism is the view that I am the universe
  that all that exists is me and my ideas.
  Everything else is just an idea in my mind.
• Berkeley is not a solipsist. He thinks that there
  are many minds (including the mind of God that
  sees all) and that we can all have ideas of the
  same object.

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Idealism vs. Materialism

• Idealism is standardly contrasted with
  materialism.
• As with idealism, the word gets used rather
  differently today. Materialism in philosophical
  contexts does not mean the desire for material
  wealth etc., it means a theory based on the
  claim that matter is the fundamental stuff out
  of which the universe is made.

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Dualisms

• Berkeley represents a radical break from the view
  of Descartes. Descartes was a Dualist he
  argued that the universe had two basic and
  completely different kinds of stuff
• Matter extended in space and non-thinking
• Mind (ideas) unextended in space and thinking
• Since nothing could be both extended and
  unextended, mind and matter had to be
  fundamentally different stuff, argued Descartes.

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Mind-Body interaction

• One of the lasting problems arising from
  Descartes dualist position was how something
  extended (matter) could possibly have any causal
  interaction whatsoever with stuff that had no
  extension (mind).
• Since (most would agree) their clearly is
  interaction between the two, Descartes suggested
  that it took place in the pineal gland (in the
  brain), but ultimately admitted he didnt have
  much of a clue how.
• Locke, avoided being drawn on such metaphysical
  speculations, and took the view that how the
  mental and the material interacted was something
  we cant know.

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Problems solved?

• Berkeleys theory, in one swoop, dissolves two
  major philosophical problems
• 1. The Veil of Perception.
• There is no veil at all since ideas in minds are
  what is real and are all that is real. Ideas in
  our minds are not representations of a
  mind-independent world.
• 2. The Mind-Body problem.
• There is no interaction between the mental and
  the physical, since all that exists are the
  contents of minds.

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Some Berkeleyan Arguments

• So why does Berkeley think that all that exists
  are ideas?
• His critical arguments against the materialist
  hypothesis boil down to two claims that the
  hypothesis of a material world is
• 1) superfluous and
• 2) incoherent

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Superfluity of the material

• Berkeley suggests that the hypothesis of an
  external material world adds absolutely nothing
  to our understanding of the universe.
• Try to think of what difference there would be
  between a world where there was matter causing
  our ideas, and a world where there was only the
  ideas.
• Can you think of a empirical difference? If so,
  what?

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Superfluity of the material

• In a sense, Berkeley tries to turn the table on
  the skeptical Evil Demon argument (or
  Matrix-style situation).
• Such skeptical arguments hinge on the supposition
  that it is logically possible for our experience
  to be precisely the same regardless of whether
  there was an external world or not.
• Since all we have to go on is experience, a
  hypothesis that makes no difference whatsoever to
  our experience cannot explain anything.

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Superfluity of the material

• But, the critic might still respond Even if we
  grant that it is logically possible for there not
  to be an external material world, surely the
  existence of such a world, running according to
  natural laws, helps to explain our experiences
  (Locke their law-like regularity, our inability
  to will away certain experiences such as pain) in
  a way that idealism cannot.

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Imagination and perception

• Berkeley grants that some experiences we can
  control. The former we call imagination, and the
  latter, perception. This difference needs
  explanation.
• But Berkeley argues that the materialist
  explanation loses out to the idealist explanation
  on two counts.
• Firstly (as well see) he thinks the materialist
  hypothesis is incoherent.

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Mental causation

• Secondly, Berkeley argues that we have not the
  slightest sliver of direct evidence that our
  perceptual ideas are, or even can be, caused by
  material bodies beyond our minds. But, by
  contrast, we do have direct evidence that ideas
  can be caused by minds we know that we can
  cause images in our imagination just by willing
  it.
• The simplest and most reasonably explanation,
  therefore, is that our perceptual ideas are also
  caused by a mind willing them, but since we
  cannot control those ideas, the mind cannot be
  our own.

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The incoherence argument

• Berkeley lays most argumentative weight for his
  idealism on what he sometimes calls his Master
  argument the incoherence argument.
• The first element of this argument is we can
  never have an idea (an experience) of the cause
  of our ideas.
• We hear a sound (never its cause) we see a
  colour (never its cause), etc. Causes themselves
  that is things beyond our sensations that are
  not themselves ideas cannot, by definition, be
  sensed or experienced.

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The incoherence argument

• The second element of his argument is his
  likeness principle. Namely nothing can
  resemble an idea except another idea.
• If the likeness principle is correct, then it
  becomes incoherent to speak of an idea of a
  mind-independent material world.

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The incoherence argument

• Just try to imagine something that is
  mind-independent. What is it like?
• Berkeley argues that when we take ourselves to be
  thinking about something existing without being
  perceived, we tacitly forget that we are (in our
  imagination, in this case) perceiving it.

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The incoherence argument

• Thus, Berkeley argues, whenever you try to say or
  think something coherent about anything at all (a
  chair say) that statement or thought will
  ultimately be about nothing more than a set of
  ideas in your mind.
• When you talk about the chair or Venus, you
  are actually talking about your ideas that is
  the only significance you can attach to you
  words.
• What would Descartes say?

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Locke and Berkeley

• Locke argues that the mind represents the
  external world, a world we know only indirectly
  through our ideas.
• Locke admits that there is no good reason to
  suppose that the secondary qualities resemble
  anything in the object itself. There is a quality
  of yellowness in the banana, but that is just a
  power in the banana to cause yellow ideas in us
  that quality does not resemble the idea of
  yellowness in our minds.

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Locke and Berkeley

• Locke, however, takes a different view of primary
  qualities (bulk, extension, figure, number, and
  motion). These ideas, Locke suggests, resemble a
  quality in the object itself.
• Berkeley thinks what goes for so called secondary
  qualities goes for primary qualities as well.

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Berkeley on primary qualities

• Berkeley argues that all the so-called primary
  qualities vary relative to the experiencer and
  hence are equally mind-dependent.
• Size (extension) is relative what is large to a
  mite is small to us.
• Shape (figure) smooth shapes to the naked eye
  look irregular through a microscope.

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Berkeley on primary qualities

• Motion Also, motion is clearly relative to the
  perceiver. (In his Three Dialogues, he also
  suggests that some minds may experience time at
  different rates. Since motion is spatial movement
  divided by time, motion would be faster to the
  slower mind.)
• Solidity Some things will appear hard to one
  animal but soft to another (much stronger animal).

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Berkeley on primary qualities

• Number That number is not something in the
  object is clear from the fact that it varies
  according to how one considers the object.
• A pack of cards, for example, is one in number
  only so long as we consider it in our minds as a
  pack of cards. It is also 4 in number considered
  as suits, 52 in number if we consider it as
  cards, etc.

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Mind-dependence and relativity

• Berkeleys arguments for the mind-dependence of
  primary qualities draws on the perceiver-relativit
  y of perception. Primary qualities are just as
  much relational properties dependent on the
  perceiver as secondary qualities are.
• Hence, primary qualities are likewise not
  intrinsic to objects and no idea of primary
  qualities can be said to resemble anything in the
  object itself, as Locke mistakenly supposes.

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Abstract ideas

• Berkeley is also famous for arguing that we can
  never form abstract ideas. For Berkeley, unlike
  Locke, every idea is particular.
• For example, just try to frame an idea of a
  triangle that does not have any particular
  internal angles. Can you do it? Berkeley thinks
  this is impossible.
• Similarly, try to frame an idea of a triangle
  that lacks any particular colour. Can you do
  that? Berkeley thinks you cant.

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General ideas

• Berkeley is not denying that we can have general
  ideas, such as a general idea of a triangle.
• But what this amounts to, he argues, is taking a
  particular idea and simply ignoring any
  particular features that are not relevant to it
  being a triangle. What is called an abstract
  idea is just an arbitrary particular idea with
  some particular properties ignored.

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Some criticisms

• One of the most prominent criticisms of Berkeley
  concerns the existence of things when they are
  not perceived. Such as when no one is in the
  room, before anyone perceived some object, or
  after everyone ceases to perceive some object.
• Surely, it is suggested, it is plainly absurd to
  suggest that the tables and chairs stop existing
  when we leave the room or even whilst we blink!
  Surely the Earth existed before life emerged to
  perceive it!

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Berkeley and God

• Berkeley agrees that its absurd. But he has two
  rejoinders.
• 1. Something ceases to exist only if it is not
  perceived by any mind. The reality of a chair,
  say, is entirely objective in the sense that it
  does not depend on any particular individual
  perceiving it.
• 2. An all-knowing God perceives everything, and
  hence even without our presence, objects continue
  to exist. (Berkeleys central reason for thinking
  there is a God is as explanation for our lack of
  control over our perception.)

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Two accounts

• Berkeley actually offers a couple of explanations
  for the existence of tables when not observed by
  us
• The table I write on, I say, exists, that is, I
  see and feel it and if I were out of my study I
  should say it existed, meaning thereby that if I
  was in my study I might perceive it, or that some
  other spirit actually does perceive it. (269
  emphasis added)

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The counterfactual account

• Thus, in addition to the God hypothesis, he also
  offers what might be called the counterfactual
  account of the existence of objects not currently
  observed to say that something exists means
  that if one were in the right circumstances (in
  the room), then one would have perceptions of the
  object.

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Illusion vs. reality

• A similar point addresses another common
  criticism if Berkeley were right, there would
  be no difference between illusions or
  hallucinations on the one hand, and reality on
  the other, since they are all ideas in minds.
• Berkeley argues that Illusion is essentially a
  word we apply to perceptions that are experienced
  entirely privately and which are not shared by
  other minds. Reality is objective in the sense
  that it is, in principle, publicly accessible to
  others.
• Is this response adequate? Can there be
  collective hallucinations?

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Ideas of the same object?

• Berkeley supposes that we can all have ideas of
  the same object. But no two persons ideas are
  the same in their particulars.
• For instance, the same table looks different
  from different positions. What unites such ideas
  into ideas of the same publicly perceivable
  object if not that they are ideas of a single
  mind-independent object?