Monday, January 16, 2006 PHL 105Y

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Monday, January 16, 2006PHL 105Y

• For Wednesday, read ch. 9-10 of Russells The
  Problems of Philosophy (pages 70-76 in the Pojman
  book)
• For tutorial this Friday, answer one of the
  following questions
• In chapter 9, Russell argues that universals like
  whiteness are not just mental entities. How
  does he argue for this point?
• How does Russell reach the conclusion, in chapter
  10, that all our knowledge of truths depends
  upon our intuitive knowledge?

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Bertrand Russells

• The Problems of Philosophy (1912)

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Sense data signs of something beyond themselves?

• Russell argues that in experience we are
  immediately acquainted only with our own sense
  data the question is how we move from this
  immediate knowledge of something private to a
  belief in the existence of distinct public,
  external objects
• What is it about sense data that makes them
  suggest something beyond themselves?

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The real cat makes senseFree-floating sense
data are confusing

• If I think that Im seeing nothing but sense
  data, its not the same cat when I get home as
  when I left (and theres no explanation of why
  its hungry) our experience becomes utterly
  inexplicable when regarded as mere movements and
  changes of patches of colour... (49)
• Does this really give us a reason to accept that
  the external cat exists? Why or why not?

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Why we believe in reality

• Of course we dont have to go through Russells
  reasoning to believe in the outer world we
  believe in it instinctively, before doing
  philosophy.
• However, Russell thinks we can justify the
  belief it gives a coherent system to our account
  of our experience, so there is no good reason to
  reject it.

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Why we believe in reality

• There can never be any reason for rejecting one
  instinctive belief except that it clashes with
  others thus, if they are found to harmonize, the
  whole system becomes worthy of acceptance. (50)

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Why we believe in reality

• There can never be any reason for rejecting one
  instinctive belief except that it clashes with
  others thus, if they are found to harmonize, the
  whole system becomes worthy of acceptance. (50)
• How might someone criticize this view?
• How does Russell seem to view reasons for
  believing things?

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Chapter 3The Nature of Matter
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Does matter have a colour?

• The light we see is not a form of wave-motion,
  but something quite different
• The qualities of our sense data do not carry over
  directly into the world sense data are not
  public objects (we mean by light just that which
  a blind man can never understand, and which we
  can never describe to him)

10
Space and time

• Matter is in space, but it is not in the space
  we see or feel (why not?)

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Space and time

• The coin is objectively round even if it appears
  oval from the perspective of various observers
  the real, public shape (the shape of science) is
  different from the apparent, private shapes
• Objective space is connected with private space,
  but not identical to it

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Space and time

• How is objective/public space connected with
  subjective/experienced/private space?
• The public and private spaces are correlated as
  far as the order of objects is concerned we are
  not in touch with the essential nature of
  physical space (in fact, we can know nothing of
  what it is in itself)
• A similar story is told about time

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Space and time

• Russells way of connecting subjective space and
  time with connected with objective space and time
  by saying that that they put objects in the same
  order is (physicists and philosophers now think)
  too simple, but it does seem useful to notice
  both that subjective and objective space and time
  can be distinguished, and also that they can be
  correlated in some way there is some meaningful
  relationship between the two (even if its more
  complex than Russell thought)

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Chapter 4 Idealism
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What is matter really like?

• So far weve figured out
• Physical objects are different from sense data
• Physical objects are correlated with sense data
  their order corresponds in a systematic way to
  the order of our experiences

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What is matter really like?

• So far weve figured out
• Physical objects are different from sense data
• Physical objects are correlated with sense data
  their order corresponds in a systematic way to
  the order of our experiences
• However, common sense leaves us completely in
  the dark as to the true intrinsic nature of
  physical objects (53)

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Could physical objects be ideas, or something
immaterial?

• Berkeley argues that all our experience is of
  ideas
• So, based on our experience, we cant conclude
  that anything is real beyond our ideas
• (and perhaps the soul experiencing those ideas,
  or similar souls)

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Russell against Berkeley

• Russell Berkeley is confusing the minds objects
  with its acts
• You are aware of something (say, the colour of
  the table) ? the colour is the object of your
  thought
• Your being aware of the colour is not an object
  it is an act of your mind

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Russell against Berkeley

• Russell Berkeley is confusing the minds objects
  with its acts
• Moments of mental awareness (acts) have to be
  mental
• But that doesnt mean the objects of which the
  mind is aware have to be mental

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Russell against Berkeley

• When he says, ideas are in the mind, so
  everything the mind knows is mental, Berkeley
  equivocates (slides illegitimately) between two
  meanings of idea
• Ideas (conceived of as mental acts) really are in
  the mind ideas (conceived of as things the mind
  is aware of) really can be outside the mind

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What is a mind?

• The faculty of being acquainted with things
  other than itself is the main characteristic of a
  mind. (55)

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Knowing about things beyond our experience

• Russell thinks we need to distinguish two
  meanings of know
• 1) Knowledge by description (the kind of
  knowledge we have when we judge that a certain
  proposition is true)
• 2) Knowledge by acquaintance (the kind of
  knowledge you have when you see the colour orange
  in front of you)

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Knowing about things beyond our experience

• Russell thinks we need to distinguish two
  meanings of know
• 1) Knowledge by description (the kind of
  knowledge we have when we judge that a certain
  proposition is true) -- discursive
• 2) Knowledge by acquaintance (the kind of
  knowledge you have when you see the colour orange
  in front of you) -- immediate

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Chapter 5 Knowledge by Acquaintance and
Knowledge by Description
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Two kinds of knowledge

• Knowledge by acquaintance direct awareness of a
  thing
• No inference or calculation required immediate,
  does not require knowledge of truths

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Two kinds of knowledge

• Knowledge by acquaintance direct awareness of a
  thing
• No inference or calculation required immediate,
  does not require knowledge of truths
• Knowledge by description indirect awareness
• Requires the application of a concept, and
  knowledge of truths connecting it to things we
  are acquainted with

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Knowledge by acquaintance

• Example ones acquaintance with ones sense data
• The particular shade of colour that I am seeing
  may have many things said about it I may say
  that it is brown, that it is rather dark, and so
  on. But such statements, though they make me
  know truths about the colour, do not make me know
  the colour itself any better than I did before
  so far as concerns knowledge of the colour
  itself, as opposed to knowledge of truths about
  it, I know the colour perfectly and completely
  when I see it, and no further knowledge of it
  itself is even theoretically possible. (56)

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Knowledge by acquaintance

• Things known by acquaintance are immediately
  known to me just as they are

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Knowledge by description

• There is no state of mind in which we are
  directly aware of the table all our knowledge of
  the table is really knowledge of truths, and the
  actual thing which is the table is not, strictly
  speaking, known to us at all. (57)
• Why is the table itself not strictly speaking
  known to us?

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Knowledge by description

• Why is the table itself not strictly speaking
  known to us?
• The table is the object which is causing these
  sense data
• We infer that it is there, from our sense data
  (and we can be wrong)

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The foundation

• All our knowledge, both our knowledge of things
  and knowledge of truths, rests upon acquaintance
  as its foundation. (57)
• Note we are acquainted with sense data, but we
  are also acquainted with abstract ideas or
  universals (e.g. blueness, is north of,
  equal to) More in ch. 9 on that.

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What are we acquainted with

• Immediate sense data
• Universals (abstract ideas)

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What are we acquainted with

• Immediate sense data
• Universals (abstract ideas)
• Our memories

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What are we acquainted with

• Immediate sense data
• Universals (abstract ideas)
• Our memories
• Our reflection on our own mental lives
  (introspection)

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What are we acquainted with

• Immediate sense data
• Universals (abstract ideas)
• Our memories
• Our reflection on our own mental lives
  (introspection)
• And (perhaps!) the self

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Russell on self-awareness

• Russell thinks that self-consciousness set us
  apart from the animals they might be acquainted
  with sense data, but we are not only acquainted
  with sense data but also aware of being
  acquainted with sense data
• I can see the sun I am also acquainted with my
  seeing the sun I can reflect on my experience

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Russell on self-knowledge

• 1. When I look within, I readily see particular
  perceptions (hunger, boredom, the brown of the
  desk, pain), but not the very I who is hungry,
  bored and looking at something brown (also Humes
  view)

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Russell on self-knowledge

• 1. When I look within, I readily see particular
  perceptions (hunger, boredom, the brown of the
  desk, pain), but not the very I who is hungry,
  bored and looking at something brown (also Humes
  view)
• 2. However, I may be acquainted with the self
  though the acquaintance is hard to disentangle
  from other things (57)

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Russell on self-knowledge

• Introspection shows us things like my seeing the
  sun and here it looks like Im acquainted to
  two things related to each other a set of sense
  data, on one side, and me, on the other
• Also I know the truth that I am acquainted with
  this sense-datum and how could I know that to
  be true if I did not have acquaintance with the
  self?
• Russell suggests it is probable that we are
  acquainted with ourselves, but he also suggests
  that the issues here are complex, and his
  argument is not decisive

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Knowledge by description

• Descriptions have one of the two following forms
• a so-and-so (ambiguous description)
• the so-and-so (definite description)

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Knowledge by description

• Descriptions have one of the two following forms
• a so-and-so (ambiguous description)
• E.g. a man a large hotel
• the so-and-so (definite description)
• E.g. the person who won the 2005 Boston
  Marathon, the tallest woman on earth

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Knowledge by description

• Russell thinks that most common words and proper
  names are really descriptions
• What sort of descriptions are they? Try
  classifying the following
• Table, chair, dog
• Saddam Hussein, Paul Martin, Cher

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Knowledge by description

• Merely descriptive knowledge what you have when
  you are not acquainted with the object to which
  the description applies.
• Example
• The oldest living man is alive.
• The tallest woman on earth is more than six feet
  tall.

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Knowledge by description

• Definite descriptions should apply to a single
  object known to exist (and are otherwise
  improper) sometimes you may not know whether a
  description is improper.
• Its only proper to use a definite description
  (The person who stole my cellphone The
  person you just assaulted..) if I know that
  there is someone fitting the description. But I
  can use a description like that even if I dont
  know who it is that fits the description.

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Thoughts about particular individuals

• Saddam Hussein himself might (possibly) be
  acquainted with Saddam the rest of us know him
  through description
• Still, if we are to obtain a description which
  we know to be applicable, we shall be compelled,
  at some point, to bring in a reference to a
  particular with which we are acquainted. (59)