Logically Proper Definite Descriptions

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    Logically proper definite descriptions*

    An Essay in Honor of RUTHMARCUS

    By

    KAREL

    LAMBERT**

    Abstract

    This essay notes a striking parallel between the original Hilbert-Bernays treatment of d ef-

    inite descriptions and Russells theory of logically proper nam es. The forma l language for the

    original theory is laid out and the imp lications of a theory of vis a vis the statements that qual-

    ify as predications in a logically proper definite descriptionssense of the word predication

    different from the espoused by F rege, Russell and M einong.

    I Introduction

    In

    The Philosophy

    of

    Logical Atomism,

    Russell declared that a [logically

    proper] name can just name a particular, or, if it does not, it is not a [logically

    proper] name at all, it is a noise. This is the case because the particulars so

    named are the meanings of those [logically proper] names. In

    Principia Math-

    ematica

    Russell said, in effect, that the expression n exists, where n is a

    [logically proper] name would be insignificant, but would not be wheren n

    is replaced by its counterpart definite description.* Elsewhere Russell ex-

    Two acknowledgements are in order. First, much of what is contained in the formal

    part of

    this

    article is

    the

    result of joint work done with Paul Schweizer during an increasing-

    ly rare period in which he w as not in the rarified air of som e peak in the Himalayas, or the like.

    Whether he would subscribe to the philosophical use to w hich it has been put here, I have not

    been able to scertain. Second, I

    am

    pleased to be invited to contribute a piece in honor of Ruth

    Marcus, colleague and friend As the inven tor

    of

    the theory of d irect reference, definite descrip-

    tions have always been of considerable interest to her. So I hope she will find the animal

    that follows deserving enough to be included in w hat Russell called ou r philosophical zoo.

    **University f California, Irvine and University of Salzburg

    B. Russell, Logic and Know ledge ed. R. Marsh), Allen and Unwin, London, 1966,

    A. Whitehead B. Russell, Principiu Mathematics: Vol 1,

    2nd

    Edition, Cambridge,

    p. 187.

    University Press, 1910, pp. 174-175.

    Dialectica

    Vol. 53, No 14 1999)

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    272 Karel Lam bert

    plained, if a is a name, it

    must

    nam e ~ o m e t h i n g .~ence, in contrast to a

    sentence of the form The so and so exists, it would be impossible for a state-

    ment of the fonn a exists to be false.

    So

    here the word insignificant appar-

    ently does not mean without sense but rather som ething like is trivial.

    Many grammatically proper names -Vulcan, the name of the putative

    planet, for instance could not be logically proper names in the Russellian

    sense.

    Failing to have a referent at all, they could not name particulars, and so,

    when spoken, would only

    be

    noises. Of course, Russell himself would not have

    regarded the gram matically proper nam e Vulcan, when spoken, as m erely a

    noise. He would have believed it to be a meaningful expression falling in

    the

    category of truncated definite descriptions, and the statem ent Vulcan exists

    nontrivially false.

    An insufficiently stressed feature in the discussion whether g ramm atically

    proper names such as Vulcanor DeGaulle

    are

    truncated definite descriptions

    is that their assimilation to the category of definite descriptions depends on

    ones of definite descriptions. One reason the proviso is important is that, con-

    tra expectation perhaps, the theory of definite descriptions need not be Russel-

    lian. It might be what nowadays is called applied) negative

    free

    definite

    description theory. This kind of theory agrees with Russell vis

    u

    vis the truth

    values assigned to statements containing definite descriptions along with

    the

    necessity of scope distinctions), but rejects the peculiarly Russellian view that

    definite descriptions are not singular terms.5 In fact, this way treating definite

    descriptions is attractive to some who distinguish between names a s rigid des-

    ignators and definite descriptions as nonrigid des ignators, and treat Vulcan

    for example) as a disguised definite description.Soone could assimilate many,

    B. Russell, Introduction to Mathem atical Philosophy, George Allen and Unw in, LTD,

    London, 1919, pp. 178-179.

    B. Russell,

    Logic and Knowledge

    ed. R. Marsh), Allen and Unw in, London, 1966,

    p. 243.

    A

    singular term is an expression purporting to refer to exactly one thing. As every

    graduate student knows, Russell urged, in his famous

    1905

    essay, On Den oting, that expres-

    sions of the formthe

    so

    and

    so

    are not really refemng kinds of expressions, but rather func-

    tion in discourse more like the logical particles all and some. Negative free definite descrip-

    tion theory NFDT)was invented by R. Schock. See his Logics

    Without Existence

    Assumptions, Almqv ist and Wiksell, Stockholm, 19 68, for reference to his pioneering work of

    1963). L ater other versions of NFD T were developed by R onald Scales Attribution and exis-

    tence, University of M ichigan Microfilms, 1 969) and Tyler Burge Singular Terms and Truth,

    No[FB]s, VIII, 1974, pp. 309-325.). In these theories, expressions such asvulcan and the

    planet causing perturbations in the orbit of Mercury are singular terms, and statements such as

    The planet causing perturbations in the o rbit

    of

    Mercury exists and The planet causing per-

    turbations in the orbit of M ercury rotates are predications, but false ones. The conception of

    Fortsetzung siehe S. 73

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    Logically proper defi nite descriptions 273

    if not all, grammatically proper names to definite descriptions without thereby

    subscribing to the Russenian view that the statements, Vulcan exists, Vulcan

    rotates, DeGaulle exists and DeGaulle pontificates are not predications.

    Another reason the proviso is important is that certain theories of definite

    descriptions are not acceptable candidates for such assimilation at all. For in-

    stance, the

    original

    Hilbert-Bernays theory of definite descriptions is inade-

    quate because word strings like Vulcan exists would paradoxically, upon

    natural paraphrase, be without sense. If paraphrased as The planet causing

    perturbations in the orbit of mercury exists, the locution in question

    turns

    out

    not false, trivial or otherwise, but without sense because the basis of the con-

    stituent definite description is not provably unique; as a matter of fact, it is log-

    ically ungrammatical. And presumably the same would be true of statements

    containing DeGaulle or its counterpart definite description The man who

    wanted to die in his own arms.

    It is clear, then, that those who subscribe to the view that (at least) irref-

    erential grammatically proper names are truncated definite descriptions must

    be prepared to defend the philosophical superiority of the Russellian (or

    asymptotic Russellian) logics of definite descriptions over their adversaries,

    the Hilbert-Bernays treatment, for instance. Yet one need not look

    far

    for philo-

    sophical defenders of the superiority of a Hilbert-Bernays like logic of defi-

    nite descriptions for the purposes of mathematics or even for the purposes of

    capturing natural language reasoning. An example

    of

    the first sort is Abraham

    Robinson, and an example of the second

    sort

    is Soren Stenlund.6 Be that as it

    Fortsetzung von S.272

    predication in negative free logics is different from the conception shared by F rege, Meinong

    and Russell. The latter threesome held a statement to be a predication just in case it joins a

    general term (or n-adic predicate) to n singular terms such that its truth value true (or false)

    depends on its general term being true (or false) of the n-tuple of n-objects specified by the n

    singular terms. This cannot be

    the

    conception of predication in negative free logics because,

    for instance, in the simplest case, a predication can be false even when there is no object spec-

    ified by the singular term for

    the

    general term to

    be

    true or false) of. Nevertheless, exponents

    of the different conceptions often agree on cases. For example, Meinong, Frege in his scien-

    tific mood) and negative free logicians would ag ree that The planet causing perturbations in

    the orbit of Mercury rotates is a predication; only Ru ssell would h old otherwise.

    A. Robinson, Constrained Denotation in

    Selected Papers:

    Vol 2 eds. J. Keisler, et.

    Al.), Yale University Press, New Haven, 1979; and

    S.

    Stenlund, The Logic

    of

    Existence and

    Description, Filosofiska Studier, Uppsala, 197

    3.

    Consider, also, the following quotation by

    G.

    Kneebone Mathematical Logic and the Foundations of Mathematics, Van Nostrand,

    London, 1963, p. 93) speaking of

    the

    motivation for the Hibert-Bernays approach. He writes:

    In comm on speech we are not troubled by sentences containing descriptions which refer

    either to no object at all

    or

    to a multiplicity of objects, never use a phrase

    of

    the form

    the individual with the property P except when speaking loosely or idiomatically

    unless we believe that it refers to a unique individual; and this sugg ests that in the for-

    mal system we m ight make the introduction of a description symbol... onditional on the

    prior derivation of [an] associated [formula]

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    274

    Karel Lambert

    may, here the purpose is to examine some consequences of the original

    Hilbert-Bernays theory, namely, that when properly formalized and ap-plied

    it yields a view about definite descriptions that, in analogy with Russells dec-

    larations above about [logically proper] nam es, simply craves to be called

    the

    theory

    of

    logically proper definite descriptions.

    2.

    A

    Formalization

    of

    the Hilbert-Bemays Theory

    of

    Definite Descriptions

    The theory to be formalized here is the original theory of H ilbert-Bernays

    HB), the informal theory in the first edition of their famous

    Grundlagen der

    Mathematik.

    It is neither the Frege like theory of the second edition nor the

    presentation in most neo-H ilbert-Bernays treatments in w hich expressions *of

    the form the

    so

    and so are treated as logically grammatical even when soand

    so is not provably ~ n i q u e . ~

    The distinctive feature of the original theory is a syntactical strategy de-

    signed to ensure that definite descriptions have well-defined referents. For a

    definite description to coun t as logically grammatical, the basis of the definite

    description

    so

    and so in the so and

    so

    must be

    provably

    unique. This re-

    quirement preserves the classical notion that all singular terms, including defi-

    nite descriptions , have referents.

    Two features of the current formalization of

    HB

    need to be emphasized.

    First, the apparent circularity inherent in H B that the set of logically gram-

    matical expressions of the language depends on what is provable, but w hat is

    provable depends on the set of logically grammatical expressions can be cir-

    cumvented. The language of H B can be defined in stages, beginning with a

    definite description free base. Definite descriptions of a given language level

    can then be introduced on the basis of what is provable in the language of the

    previous level. All finite depths of em bedding of definite descrip tions are ob-

    tained by defining HB as the union of the results of the procedure just outlined

    over the finite ordinals. Second, the distinctive feature of the original HB,

    namely, that the formation rules allow the introduction of a definite descrip-

    tion just in case the basis of the defin ite descrip tion is provably unique, has the

    consequence that though the ensuing form ation rules provide an inductive

    definition of the language of HB, the set of expressions is not decidable; since

    the underlying first order logic is undecidable, the syntax of H B will a lso be

    undecidable.

    D. Hilbert

    nd

    P. Bernays, Grundlagen der Mathematik, Vol.

    1

    Springer Verlag,

    Berlin,

    1968,

    esp.

    pp.

    392-401.

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    Logically proper definite descriptions

    275

    yntax of L,,

    1.Logical constants:

    - , 3 v,

    3, i

    2.

    Variables: x,yz,.

    .

    with o r without subscripts

    3.

    Individuals constants: a,b,c, with or withou t subscripts

    4. Predicates:

    P,Q,R,

    with o r without subscripts

    Symbols from

    1 -4.

    Are used autonom ously.

    The definite description free base language IA is a standard first order lan-

    guage. That is,

    1.The singular)

    terms

    of Lo

    are

    all and only individuals constants,

    and

    2.

    the

    statements

    of

    Lo

    are defined as follows:

    a) If P is an n-ary predicate constan t, and a l,.

    ..,

    a,, are individuals

    b) a

    =

    b is a statement;

    c) If A, B are statements,

    so

    is - A, A B), A V B), and A 3 B);

    d) If A a/x)

    is

    a statement, so are

    v

    x A and 3 x A.

    constants, P a, , .

    ,

    an ) s a statement;

    The language

    L,,+],

    containing definite descriptions formed on the basis of the

    language

    L,,,

    is defined as follows:

    3.

    Th e singular) terms of L,,+l

    are

    defined as follows:

    a) If t

    is

    a singular) term of L,,, then t is a singular) term of

    L,,+,;

    b) If A is a statement of L,,, and a is a constant occurring in A, then

    if

    it

    is

    provable that

    3

    x

    V y

    A y/a)

    =

    y

    =

    x)), ixA x /a) is a sin-

    gular) term of

    L

    4.

    The statements of L,+] are defined as in

    2.

    with

    Ln+ ,

    eplacing Lo,

    t

    replacing by herein.

    t,, replacing a l,. .,a,, and

    s

    replacing a in a = b and t

    The language L=

    UL,,,

    for

    ri E a

    A statement A is provable in L,, if A is a cons equenc e of the axioms of L,, by

    Detachment M odus Ponens), and an xiom of

    L,,

    is any tauto-

    logy or instance in L n of the following schem ata:

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    276

    Karel

    Lambert

    5

    V

    x

    (A B) V x A V x B)

    6 A 3 V x A

    1 V

    x A x A ( a / x )

    8 .a = a

    9 . a = b b ( A ~ A ( a / / b ) )

    10. V x A (x/a) provided A is an axiom and a is a (singular) term in A

    11. A (ixA(x/a) provided A is a statement of L,+, and ixA(x/a) is a (sin-

    gular) term of L n

    The Hilbert-Bernays infortnal treatment in the first edition of the Grundlagen

    is not hierarchical (as in the formulation above), and indeed, if not rec-

    onstructed, is potentially circular. In place of

    11

    they have an inference rule,

    the i-rule, such that any instance of 11. is derivable given the provability of the

    appropriate uniqueness condition. But how can this rule be used to define the

    syntax of their object language? To what language do the premises of the in-

    ference rule belong if the formation rules of the language being defined ap-

    peal to that inference rule? Evidently the premises of the i-rule are tacitly re-

    stricted to a sub-language like

    L,+l,

    a restriction made explicit above, and,

    hence, an appropriate version of the i-rule is derivable in the preceding treat-

    ment.

    Semantics

    of

    L B

    A

    model

    for

    L,,

    is a pair .Ds a non-empty set, and I

    =

    UI,, where Ii(i

    n) is an interpretation function such that

    (la) I,(a)

    E

    D for any (singular) term a of Lo

    (2a) I,(P") is a set of n-tuples of elements of D for any n-adic predicate

    (3a) I, maps the (singular) terms of Loonto D.

    of Lo;

    I, induces a valuationfunction VM(o) efined on the set of statements of

    Lo

    as

    follows:

    (la(o)) VM(,)

    a

    = b) = T(rue) if and only if Io(a) is the same as Io(b) for

    any (singular) terms a, b of

    Lo:

    otherwise Vm(o)(a

    =

    b)

    =

    F(a1se);

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    Logically proper definite descriptions

    217

    (lb(o)) VM(o, Pn(al ..., an)

    =

    T if and only if E

    Io(Pn),where al,

    ..,

    an are (singular) terms of

    Lo:

    otherwise

    VM(o, Pn(a ... an)=

    F;

    (2a(o)) VMc0,(-A)

    =

    T if and only if VM(o,(A)

    = F,

    and otherwise it

    F =;

    (2b(o)) V,,,,(A B) =T if and only if VM(o,(A)

    =

    T and VM(o,(B)

    =

    T,

    (2c(o)) V,,,,(A V B) = T if and only if VM(o,(A)= t or VM(o,(B)

    =

    T, and

    and otherwise it = F;

    otherwise it

    =

    F;

    (2d(o)) V,(,,(A B) = T if and only if V,(,,(A) =

    F

    or VM(o,(B)

    =

    T, and

    otherwise it

    =F:

    (2e(o)) VMo (A (B) = T if and only if VM(o,(A)= VM(o,(B),and other-

    wise it

    = F:

    3)

    V,(,,('d x A) = T if and only if V,(,,(A(a/x)) for every (singular)

    term of Lo, and otherwise it =

    F.

    To accommodate definite descriptions in L,,, first the interpretation function

    In+l

    s defined as follows:

    (la(n+l)) In+l(t)

    =

    I,(t) provided t is a (singular) term of Li (i I );

    (lb(n+ll)) In+l(ixA(x/a))= d E D such that for some (singular) term b

    of Lo, Io(b)

    =

    d, and V,(,,,(A(b/a))=T, where ixA(x/a) is a (singular) term

    OfLn+1;8

    In

    nduces a valution function VM(,,)defined on the statements of Li (i n)

    as follows:

    (la(n)) V,(,,(s

    =

    t)

    =

    T if and only if In(s) is the

    same

    as In(t), and other-

    wise it = F;

    (lb(n))V,~,,)(Pn(al,..,a,)=T if and only if Io(Pn),and

    otherwise it

    =

    F;

    This clause ensures that each term

    of

    the

    form

    ixA x/a) is assigned the unique element

    d

    of

    D that satisfies the basis A x/a).

    Its

    adequacy is guaranteed by con dition 3a) in the defi-

    nition of a model.

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    278

    Karel Lambert

    The cases (2a(n))-(2e(n)) for the connectives are similar to the cases of

    (1

    a 0))

    (

    e(o)) above;

    (3n) VMMcn)(d

    A )

    =

    T if and only if V,(, A(a/x))

    =

    T

    for every (singular)

    term a of Lo, and otherwise it

    = F.

    3. Logically Proper De3nite Descriptions

    Let a be ones favorite logically proper name perhaps the demonstra-

    tive this, to take a word Russell himself once favored. Consider now the

    predicate same as this. It is provable in L HB that there is exactly one thing

    the same as this.

    So

    the definite description ix(x

    =

    this) is a singular term of

    LHB, nd, indeed, picks out the same element of

    D

    of which the basis of that

    definite description is provably unique he object of

    D

    assigned to this. If

    arithmetic is added to

    LHB,

    a taken to be 4nd b taken to be S he same

    holds for the expression ix(x is a positive whole number between nd

    6 ,

    except that the referent in this case would be 5 Moreover,

    if

    one wishes to

    Quine-ize singular terms by adding special predicates such as thisizes to the

    language, with appropriate axioms governing these special predicates, the

    expression ix(x thisizes) would also qualify as a singular term in the extended

    language in question.

    Consider now statements of the forms, respectively, t exists and a does

    not exist, where t is any of the definite descriptions mentioned in the previ-

    ous paragraph. Let exists be understood as an abbreviation for x(x

    =... ).

    Statements of the first form would be true, and trivially true at that. Similarly

    statements of the second form would be trivially false. Moreover, one can say

    precisely what it would mean to say that the definite descriptions making up

    the subjects of these statements would be mere noises, were they not to def-

    initely describe an individual in D; they would be logical gibberish. It seems

    appropriate, therefore, to call such expressions

    logically proper definite

    descriptions

    at least as measured by the characteristics associated with log-

    ically proper names enunciated in the opening paragraph of this essay.

    This gives rise to the Russell-like questions: Which coroquial definite

    descriptions are logically proper definite descriptions? How are statements

    containing logically improper definite descriptions to be analyzed? The

    answer to the first question is straightforward enough; no colloquial expres-

    sion of the form the

    so

    and so, where so and so is not provably unique can

    be a logically proper definite description. In particular, neither the planet

    causing the perturbations in the orbit of Mercury, nor any of its relatives, can

    be logically proper definite descriptions. Presumably also the man who

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    Logically proper definite descriptions

    279

    wanted to die in his own

    arms

    is not a logically proper definite description.

    But suffixing exists to this pair of expressions does not yield a pair

    of

    non-

    sensical statements. What one gets is, respectively, a nontrivial falsehood,

    French refuter notwithstanding, and a no ntrivial truth. H ow to analy ze them?

    Exactly as Q uine does in Word and Object. To illustrate, the statement The

    planet causing perturbations in the orbit of M ercury would b e paraphrased as

    There is exactly on e thing that

    is

    a planet c ausing perturbations in the orbit

    of Mercury, a false statement that does not contain a phrase of the form

    the

    so

    and

    so.

    I conjecture that any truth o r falsehood containing a phrase of the

    form the

    so

    and

    so,

    where so and

    so

    is not provably unique, can be treated a

    la Quine, given the requisite sensitivity to scope considerations in the case of

    non-atomic statements. Of course, the Russell program about the elimination

    of grammatically proper names via logically improper definite descriptions

    proceeds as usual. Vulcan may be taken

    as

    a truncated version of the planet

    causing perturbations in the orbit of M ercury, DeG aulle as a truncated ver-

    sion of the man w ho wanted to die in his own arms, and the resulting state-

    ments containing these descriptive phrases paraphrased into the purely quan-

    tificational fragment of

    L,,

    a la Quine.

    Turning to the pair of colloquial statements The num ber between

    4

    nd 6

    exists and The king of France in 1999exists, it might be thought that exists

    means different things in these two cases because their paraphrases into

    L,,

    are quite different. Th e former, containing a logically proper definite descrip-

    tion, gets paraphrased as 3x x

    =

    the number between 4 nd 6), but the latter

    gets paraphrased as3 z V y) y is a king of France in 1999= y

    =

    z .

    However,

    this conclusion

    is

    incorrect. exists is a silent partner in the latter paraphrase

    because that paraphrase is logically equivalent to 3z Vy) y is a king of

    France in 1999=

    y =

    z)

    3

    x x

    =

    z)). W hat is true and important) is that

    only the first of conoquial statements is a predication because only the first

    definite description is logically proper, and hen ce qualifies a s a singular term.

    So

    only the first of this pair of statements gets evaluated by appealing in part)

    to the object which the constituent definite description refers

    to.

    In virtue of their similarity of properties, the question a rises whether, con-

    tra Russell, logically proper nam es m ight not be eliminated in favor of logi-

    cally proper definite de sc r i p ti ~ n s. ~his would have the advantage of giving

    The attempt here to produce a theory of logica lly proper definite descriptions deliber-

    ately avoids the ep istemological overtones in Russels account of logically proper names, an

    account that appeals

    to

    entities directly apprehended sense data for the Russell

    of

    The

    Philosophy

    ofLogicuZAtornisrn).t is more in the spirit

    of

    Priors attempts to get at the logical

    essence of Russells notion, what Prior called Ru ssellian names. Se e Objects of Thought

    Fortsetzung siehe S.280

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    280

    Karel Lambert

    formal substance to Russells view that logically proper names that failed to

    name would be insignificant because one could then pin the insignificance on

    a concrete violation of the rules of logical grammar.

    There is, however, a serious problem confronting the current proposal to

    eliminate logically proper names. The problem is that since what is provable

    depends on what the axioms and/or rules of inference are in a given theory,

    which definite descriptions will turn out to be logically perfect becomes a rel-

    ative matter. For instance, in some set theories the expressionix(Vy)(ye x =

    y = y) will be logically perfect and in others not because in some set theories

    the basis of this definite description is not provably unique. And the same

    would be true of definite descriptions in opposed empirical theories. But the

    relativity outlined seems quite alien to Russells conception of a logically

    proper name. Moreover, if a, b, c... Of L are taken to be the formal coun-

    terparts of logically proper names, the very characterization of ixA(x/a)as a

    singular term requires, on pain of circularity, that there be some (unanalyzed)

    singular terms, hence some irreducible logically proper names.

    The provability requirement for a definite description to qualify as a sin-

    gular term, and thence as logically proper, is very strong. Following Carnap,l0

    one might think of replacing it in clause 3(b) above by the weaker requirement

    that the uniqueness of the basis of the putative description simply be true. This

    might now allow the president of the

    U.S.

    in

    1999

    to count as a (singular)

    term, but this proposal to weaken the condition determining when an expres-

    sion of the form ixA(x/a) is to count as a (singular) term faces a possible for-

    mal obstacle. Provability is a syntactical property, but truth is a semantical

    property. Since the true statements of the formal language require an inde-

    pendent characterization of statement, it is not clear that a non-circular for-

    malization of

    L

    is possible. Perhaps a levels of language approach of the

    sort above can be achieved, but that is a beyond the narrow purposes of this

    essay.

    The undecidability of

    Lm vis a vis

    what constitutes a statement is seen by

    many as a serious disadvantage, given provability (or truth) of the unique-

    ness of the basis of a definite description as a requirement for (singular) term-

    hood. Here is the way Carnap puts the matter in

    eaning A n d Necessity.

    Fortsetzung von

    S. 79

    eds.

    P.

    Geach and

    A

    Kenny), Clarendon Press, Oxford, 1971, esp. Chapter

    10.

    For a brief

    examination of Priors

    efforts,

    see K. Lambert, Russellian Nam es: Notes on a

    theory

    of Arthur

    Prior

    in

    Logic

    nd

    Reality,

    ed.

    i.

    Copeland) Clarendon Press, Oxford, 1996, pp.

    41

    1-419)

    OR.

    Carnap,

    Meaning

    And

    Necessity

    Univ. of Chicago Press, Chicago,

    1947,

    pp. 33-34.

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    Logically proper definite descriptions

    28

    1

    ... this method has a serious disadvantage, although of chiefly a theo-

    retical nature: the rules of, Formation become indefinite, i.e. there is no

    general procedure for determining whether any given expression of the

    form

    [

    e.g., PixQx] is a [statement] of the system (no matter whether

    true or false or provable or not).

    In addition, he says:

    For systems containing factual [statements], the disadvantage would be

    still greater, because here the question of whether a given expression is

    a statement or not would, in general, depend on the contingency of

    facts.

    In the first quotation, it is important to note Carnaps emphasis on the

    chiefly theoretical nature of the disadvantage to the original

    HB

    theory.

    Now it may be annoying not to know whether the statement The explanation

    of the results in Lamberts Experiment on latent inference learning by the

    Expectancy Theory shows the transitive character of e~pectation~eally is a

    predication, and hence whether certain inferential procedures are applicable to

    it (for instance, substitutivity of identity). But philosophers need not be com-

    pletely disabled by that consideration

    vis

    a vis computation of its truth or fal-

    sity. The example expression clearly is a sensible statement and its truth or

    falsity may be ascertained by paraphrasing it into

    L,

    a la Quine. If it were to

    turn out to be a predication after all, this would not change its truth-value, only

    the method (or methods) of computing that truth-value.

    Turning to the second quotation, whether a statement is to be regarded as a

    predication often depends on how the facts

    tur

    out. For instance, suppose it

    were to

    tur

    out that the name, Baxter, picked out by U.S. citizens Smith and

    his wife for their planned, but not yet conceived first boy, should fail to refer

    (because, for example, Smiths wife subsequently miscarried). Then the truth

    value of Baxter (that is, the planned first born son of Smith and his wife) is

    an American could not be ascertained by seeing whether the predicate is an

    American is true (or false) of the individual picked out by the singular term the

    first born son of Smith andhis wife, there being no such individual.

    So,

    though

    a false statement, it would not be a predication. The tie between singular term,

    reference and predication characteristic of Russells theory of logically proper

    names is reflected in the current theory of logically proper definite descriptions.

    Ibid., p. 34.

    l

    Ibid., p. 34.

    l 3

    K. Lambert,

    A

    study

    of

    latent in ference, Canadian Journal

    of

    Psychology, 14, 1960,

    pp. 45-50.

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    282

    Karel

    Lambert

    If a definite description is a singular term it must refer, and (at least) any atomic

    statement in which it occurs must be a predication. On the other hand, deter-

    mination of whether a definite description is a singular term, a logically signif-

    icant unit, hence whether statements in which it is contained are predications,

    may be indefinite for lack of proof of the uniqueness of the basis of that definite

    description (or, less strictly, because the facts are not

    all

    in).

    This talk of predication shows a particular value of HB qua theory of logi-

    cally proper definite descriptions. On the classical view of predication, state-

    ments containing definite descriptions in subject position were uniformly

    taken by Russell to be non-predications because definite descriptions could

    never be singular terms, but Frege (in his scientific mood) and Meinong re-

    garded all such statements

    s

    predications. These seemed to be the, only ways

    of regarding such statements given the principle of compositionality, the prin-

    ciple that the value of a complex is a function of the values of its logically

    grammatical parts. Russell preserved the principle by denying that expressions

    of the form the so and so are ever logically grammatical parts of their host

    statements, but Frege and Meinong held such expressions to be logically sig-

    nificant parts of their host statements and thus had to have values, invented or

    otherwise. HB qua theory of logically proper definite descriptions represents

    an intermediate view because i-expressionscannot fail to have referents, and

    hence statements containing them will obey the principle of compositionality.

    However, in contrast to Frege and Meinong, some such expressions in collo-

    quial discourse will not

    be

    singular terms, yet compositionality is preserved

    by treating the statements in which they occur as shorthand for existential

    statements essentially in the manner of Russell.

    To

    sum up, if an expression

    of

    the form the

    so

    and so is to be regarded as

    a singular term a la

    HB,

    then it will have the status of something like a logi-

    cally proper name. To

    be

    sure this means that there is a certain indefiniteness

    about which expressions of ordinary discourse of the form the so and

    so

    so

    qualify. However,

    this

    should cause no more discomfiture than the familiar

    indefiniteness surrounding the question which statements of colloquial dis-

    course qualify s (or will turn out to be) predications, in the classical sense of

    predication.

    Dialectica

    Vol. 53,No /4 1999)