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On Denoting

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Title: On Denoting


1
On Denoting
  • Bertrand Russell

2
Weve got some serious problems
3
A Puzzle About Identity
  • Indiscernibility of Identicals If a b then
    whatever is true of one is true of the other.
  • If a is identical with b, whatever is true of
    the one is true of the other, and either may be
    substituted for the other in any proposition
    without altering the truth or falsehood of that
    proposition. Now George IV wished to know whether
    Scott was the author of Waverly, and in fact
    Scott was the author of Waverly. Hence we may
    substitute Scott for the author of Waverly and
    thereby prove that George IV wished to know
    whether Scott was Scott.
  • Problem contexts in which substitutivity salve
    veritate fails, e.g.
  • George IV wondered whether ___ wrote Waverly.
  • Necessarily ___ is odd.

4
A Puzzle About Excluded Middle
  • The Law of Excluded Middle For any proposition,
    P, either P or not-P
  • By the Law of Excluded Middle, either A is B
    or A is not B must be true. Hence either the
    present King of France is bald or the present
    King of France is not bald must be true. Yet if
    we enumerated the things that are bald and then
    the things that are not bald, we should not find
    the present King of France in either list.
  • Problem When the subject term of a sentence
    fails to refer, excluded middle fails, e.g.
  • The present King of France is bald.
  • George W. Bushs son is a plumber

5
A Puzzle About Negative Existentials
  • A proposition cannot be about a non-entity to be
    either true or false the subject term of a
    singular statement must refer to something.
  • Consider the proposition A differs from B. If
    this is true, there is a difference between A and
    B, which fact may be expressed in the formthe
    difference between A and B subsists. But if it
    is false that A differs from B, then there is no
    difference between A and B, which fact may be may
    be expressed in the form, the difference between
    A and B does not subsist. But how can a
    non-entity be the subject of a proposition?...If
    A and B do not differ, to suppose either that
    there is, or that there is not, such an object as
    the difference between A and B seems equally
    impossible.
  • Problem Negative existentials, sentences of the
    form x doesnt exist seem to commit us to the
    existence of x and then say of it that it doesnt
    existwhich is a contradiction.
  • Santa Claus doesnt exist
  • Unicorns dont exist

6
The Source of Our Problems
  • We are mislead by language!
  • Surface grammar obscures the true logical form
    of propositions
  • Our failure to recognize the true logical form
    beneath the surface is responsible for the
    puzzles
  • Subject-predicate form of some sentences is
    misleading
  • Russell proposes an account of the true logical
    form of propositions that provides solutions to
    the puzzles
  • He criticizes alternative approaches of Meinong
    and Frege
  • And shows how his account deals with the puzzles

7
An Ideal Language
  • Disagreement about what philosophy is supposed to
    be doing
  • Analyzing ordinary language or
  • Translating into an ideal language that reveals
    true logical form
  • Russell proposes translating ordinary language
    into an ideal language that will avoid puzzles
    and paradoxes.
  • The language that reveals logical form and so
    allows us to explain validity and to provide
    solutions without getting into crazy metaphysics
    is . . .
  • PREDICATE LOGIC WITH IDENTITY!

8
Predicate Logic Vocabulary
  • Connectives ? , ? , , ? , and ?
  • Individual Constants lower case letters of the
    alphabet (a, b, c,, u, v, w)
  • Predicates upper case letters (A, B, C,, X, Y,
    Z)
  • Variables x, y and z
  • Quantifiers
  • Existential (? variable), e.g. (?x), (?y)
  • Universal (variable), e.g. (x), (y)
  • Identity (a special predicate)

9
Basic Predicate Logic Translation
  • Singular propositions
  • Russell was a philosopher.Pr
  • Russell was Moores friend.Frm
  • Russell authored Principia Mathematica with
    Whitehead.Arwp
  • General propositions
  • Everything is material(x)Mx
  • There is a God.(?x)Gx

10
Identity
  • Identity is an equivalence relation
  • Reflexive everything is identical to itselfx
    x
  • Symmetric if one thing is identical to another
    the other is identical to the firstIf x y
    then y x
  • Transitive if one things identical to a second
    and the seconds identical to a third then the
    first is identical to the thirdIf x y and y
    z, then x z
  • Identity is an indiscernibility relation
  • Indiscernibility of Identicals if x y then
    whatever is true of x is true of y and vice
    versa.

11
Ordinary language is deceptive!
  • According to Russell, what appear to be simple
    singular statements are often really more
    complicated existentially quantified statements.
  • I met a man
  • Mm (wrong! a man is not the name of an
    individual!)
  • (?x)Mx (correct translation)
  • Even ordinary language statements that include
    ordinary proper names are deceptive ordinary
    proper names are really disguised descriptions
  • Apollo lives on Mount Olympus
  • (?x)(x is sun god and x is Letos son and
    Artemis twin brother andand x lives on Mount
    Olympus
  • Puzzles arise because we think statements that
    involve denoting expressions are singular
    statements when they are really existential and
    generaland involve quantifiers and complicated
    logical machinery!

12
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13
Denoting
  • The subject of denoting is of very great
    importance, not only in logic and mathematics,
    but also in the theory of knowledge.
  • No general characterization of denoting is given,
    only a list of denoting phrases.
  • A man
  • Some man
  • Any man
  • Every man
  • All men
  • The present King of England
  • A phrase is denoting solely in virtue of its
    form.

14
Denoting Phrases and Denotation
  • Russell considers three cases
  • Denoting phrases that do not denote anything,
    e.g. the present King of France in 1905
  • Denoting phrases that denote one definite object,
    e.g. the present King of England in 1905
  • Denoting phrases that denote ambiguously, e.g. a
    man
  • We want an account that will accommodate all
    three kinds of cases without paradox
  • And explain how we can think and talk about many
    things with which we are not acquainted but
    only know by description.

15
Paraphrasing Away Denoting Phrases
  • I use C(x) to mean a proposition in which x is
    a constituent, where x, the variable, is
    essentially and wholly undetermined.
  • We paraphrase away everything, nothing, and
    something as follows
  • C(everything) means C(x) is always true (x)Cx
  • Everything is material for all x, x is material
  • C(nothing) means C(x) is is false is always
    true (x) ? Cx
  • Nothing is free for all x, it is not the case
    that x is free
  • C(something) means It is false that C(x) is
    false is always true ? (x) ? C(x) i.e. (?x)Cx
  • Something smells there exists an x such that x
    smells.

16
More Translations
  • I met a man
  • I met x and x is human is not always false
    (?x)(Mx ? Hx)
  • All men are mortal
  • If x is human then x is mortal is always true
    (x)(Hx ? Mx)
  • No men are perfect
  • If x is human then x is perfect is false is
    always true (x)(Hx ? ? Px)
  • Some men are philosophers
  • x is human and x is a philosopher is not always
    false (?x)(Hx ? Px)

17
Definite Descriptions
  • The denoting phrase in the sentence The father
    of Charles II was executed involves
  • Existence x was father of Charles II, for some
    value of x.
  • Uniqueness if y was father of Charles II, then y
    is identical with x, for any value of x who was
    father of Charles II and any value of y.
  • To convey the uniqueness condition we need to
    introduce an additional special predicate, viz
    IDENTITY to produce the following translation
  • There exists an x such that x is the father of
    Charles II
  • For all y, if y is the father of Charles II then
    x y
  • x was executed

18
Denoting Phrases All Gone!
  • We have now paraphrased away all denoting phrases
  • A man
  • Some man
  • Any man
  • Every man
  • All men
  • The present King of England
  • Weve gotten rid of them in favor of logical
    machinery--and this will enable us to solve all
    three puzzles

19
The Identity Puzzle
  • Indiscernibility of Identiticals
    (substitutivity) If a is identical with beither
    may be substituted for the otherwithout altering
    the truth or falsity of the proposition
  • Apparent Counterexample George IV wished to know
    whether Scott was the author of Waverly
  • Scott the author of Waverly
  • By substitutivity principle, George IV wished to
    know whether Scott was Scott
  • But George IV did not wish to know whether Scott
    was Scott (he knew that!)
  • So, contrary to the principle we have a case
    where substituting a different name for the same
    objects makes a true proposition falsewhich is
    unacceptable!

20
Substitutivity Failures
  • There are some contexts in which it looks like we
    cannot freely substitute identicals for
    identicals
  • These include intentional contexts which occur in
    sentences that ascribe certain mental states,
    e.g.
  • The Minoans didnt believe that the Morning Star
    was identical to the Evening Star.
  • George IV wondered whether Scott was the author
    of Waverly.
  • The Problem everyone knows that everything is
    identical with itself BUT
  • The Minoans believed that the Morning Star was
    identical to the Morning Star, but not that the
    Morning Star was identical to the Evening Star.
  • George IV didnt wonder whether Scott was
    identical to Scott but did wonder whether Scott
    was identical to the author of Waverly.

21
Freges Puzzle
  • How can true identity statements be informative?
  • The Morning Star The Evening Star
  • What makes this true is the fact that The
    Morning Star and The Evening Star refer to the
    same object, viz. the planet Venus so it looks
    like the identity statement just says that Venus,
    like everything else, is identical to itself!
  • But everyone knows that everything is identical
    to itself so what do we know that the Minoans
    didnt know? And what did George IV wonder about?
    Surely not whether Scott was identical to
    himself!
  • Russell discusses Freges way of dealing with
    this and related issues (pp 4 5) by
    distinguishing the meaning and denotation of
    denoting expressions well deal with this when
    we get to Fregenot now.

22
Scope Ambiguity
  • Guest I thought your yacht was larger than it
    is.
  • Touchy Yacht Owner No, my yacht is not larger
    than it is.
  • 1 The size I thought your yacht was is greater
    than the size your yacht is.
  • Theres a certain size, x, and I thought that x
    was the size of your yacht but x is greater than
    the size of your yacht.
  • 2 I thought the size of your yacht was greater
    than the size of your yacht.
  • I thought that theres a certain size, x which is
    the size of your yacht but x is greater than the
    size of your yacht.
  • In 1 the Guest does not believe that the size of
    the Owners yacht is greater than it is.
    Likewise, in the correct reading George IV
    wondered, George IV does not wonder whether
    Scott is Scott.

23
Russells Solution
  • George IV wished to know whether Scott was the
    author of Waverly
  • 1 George IV wished to know whether one and only
    one man wrote Waverly and Scott was that man
  • Secondary occurrence of the author of
    WaverlyGeorge IV wished to know whether
    (?x)Axw ? (y)(Ayw ? yx) ? xs
  • 2 One and only one man wrote Waverly and George
    IV wished to know whether Scott was that man
  • Primary occurrence of the author of
    Waverly(?x)Axw ? (y)(Ayw ? yx) ? George IV
    wished to know whether xs
  • 1, not 2, is the correct interpretation of the
    original sentence. What George IV didnt know but
    wanted to know, was whether the proposition
    (?x)Axw ? (y)(Ayw ? yx) ? xs was true, and
    that is not the same proposition as ss which is
    the result of substituting s for x in 2.

24
The Excluded Middle Puzzle
  • Excluded Middle P or not P
  • Consider the sentence P The present king of
    France is bald.
  • P cant be true since there is no present king of
    France.
  • Since its not true it must be false
  • Therefore we conclude that the present King of
    France is not bald, i.e. not P
  • But thats also false since there is no present
    king of France
  • But this seems to violate Excluded Middle since
    we deny both P and not P

25
Russells Solution
  • Its false that the present King of France is
    bald is ambiguous.
  • 1 There is an entity which is now king of France
    and is not bald.(?x)(Kx Bx)
  • 2 It is false that there is an entity which is
    now king of France and is bald. (?x)(Kx Bx)
  • Theres a scope ambiguity concerning negation!
  • 1is false there is no x who is King of France
    and is either bald or non-bald.
  • 2 is true.

26
The Negative Existentials Puzzle
  • Negative Existential A claim to the effect that
    something doesnt exist, e.g.
  • Santa Claus doesnt exist
  • There are no unicorns.
  • Problem the following argument
  • 1 If an individual denies the existence of
    something, then he refers to what he says does
    not exist.
  • 2 Things which do not exist cannot be referred to
    or mentioned no statement can be about them.
  • 3 Therefore, if an individual denies the
    existence of something, then what he says does
    not exist exists.

27
The Paradox of Non-Being
Parmenides posed the Paradox of Non-Being
28
Whats the problem???
  • (F) If Ferdinand is not drowned, then Ferdinand
    is my only son (p. 3)
  • Intuitively names dont have sense
    (dictionary-meaning) one cannot give a
    definition of, e.g. Ferdinand.
  • So we may say that the meaning of a name is the
    object to it denotes, e.g. Ferdinand means that
    guy
  • Therefore, if there is no object a name
    denotes,the name is meaningless
  • And so is any sentence in which it occurs.
  • If Ferdinand is drowned, i.e. there is no
    objectFerdinand denotes
  • The sentence (F) is meaningless!

29
Whats the solution???
  • (F) If Ferdinand is not drowned, then Ferdinand
    is my only son (p. 3)
  • But (F) is not meaningless, so we have a choice
  • Meinongs Solution in addition to objects that
    exist, there are also possible objects that
    subsist and even impossible objects that dont
    either subsist or exist.
  • Russells Solution Ferdinand is not really a
    name.
  • Ferdinand is my only son is not really a
    singular, subject-predicate proposition
  • Neither is The king of France is bald
    orUnicorns have one horn.
  • So lets compare these two solutions

30
Meinongs Bloated Ontology
Real things (things that actually exist)
Possibilia (dont actually exist but could they
subsist)
Impossibilia (dont exist, cant exist and dont
even subsist)
Round Squares
Married Bachelors
31
Meinongs Solution
  • It avoids the flat-out contradiction of having to
    say that some things that exist dont exist
  • Zeus subsists so in saying that Zeus doesnt
    exist, were not saying that something that
    exists doesnt exist.
  • But talk about impossible objects, e.g. round
    squares, lands us in contradictions.
  • And we cant/shouldnt arbitrarily analyze talk
    about impossible objects differently from talk
    about things that exist or subsist.
  • Furthermore, introducing impossible and merely
    possiblethings multiplies objects unnecessarily.

32
Russells Solution
  • We must abandon the view that denotation is
    what is concerned in propositions which contain
    denoting phrases.
  • We have to deal with three kinds of cases,
    examplified by
  • Unicorns dont exist.
  • The Fountain of Youth doesnt exist.
  • Apollo doesnt exist
  • Note in 1 the surface-grammatical subject is a
    general term, in 2 its a definite description,
    and in 3 its a name

33
Solution to Case 1
  • Unicorns dont exist.
  • It is not the case that there exists an x such
    that x is a Unicorn? (?x)(Ux)
  • __is a unicorn is is a predicate
  • We say theres nothing of which that predicate
    is true,
  • i.e. it is not the case that something has the
    property of being a unicorn

34
Solution to Case 2
  • The Fountain of Youth doesnt exist.
  • It is not the case that there is one and only
    one x thatsthe Fountain of Youth? (?x)Fx ?
    (y)(Fy ? y x)
  • We note that the Fountain of Youth is a
    definite description and treat it accordingly.
  • We say in effect Its false that theres a
    unique thing thats a fountain of youth.

35
Solution to Case 3
  • Apollo doesnt exist
  • It is not the case that there is one and only
    one x which is C? (?x)Cx ? (y)(Cy ? yx)
  • C is what the classical dictionary tells us is
    meant by Apollo--a description.
  • Ordinary names are disguised descriptions!
  • So Asw isnt strictly speaking (according to
    Russells metaphysical account) the correct
    translation of Scott was the author of Waverly
    since neither Scott nor Waverly are strictly
    speaking names.
  • But well pretend it is to avoid getting into
    some heavy metaphysics.

36
Genuine proper names
  • Russell distinguishes knowledge by acquaintance
    and knowledge by description.
  • Genuine proper names are names of things with
    which we are directly acquainted--our current
    sense data.
  • Genuine proper names are simply tags.
  • Ordinary names and definite descriptions attach
    to objects insofar as the objects have the
    characteristics that satisfy the descriptions.
    Theyre disguised descriptions

37
Russells Theory of Descriptions
  • On Denoting was (and by many is) viewed as the
    paradigm of analytic philosophy and one of the
    greatest pieces of philosophical writing of the
    20th century!
  • It provides the standard analysis of definite
    descriptions.
  • It stood unchallenged for over half a century.
  • And then there was Strawson
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