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  • 8/10/2019 Cogito, ergo sum: Inference or performance? by Jaakko Hintikka

    1/16

    Sorry or he

    conditionofhis

    document.

    almost

    idn't

    put

    n

    on hesystem,

    ut

    t is

    an

    mportant

    ork;

    and f

    l

    didn't o

    t

    I would

    be doing

    omething

    ess

    mportant

    t

    the moment.

    Steve

    Bayne

    .

    www.hist-analytic.org

  • 8/10/2019 Cogito, ergo sum: Inference or performance? by Jaakko Hintikka

    2/16

    WADSWORTH

    STUDIES

    IN

    PHILOSOPHICAL

    CRITICISM

    Alexander Sesonsheand, Noel Flemi.ng,

    Edi,tors

    HUMAN

    UNDERSTANDING:

    Studies

    n

    the

    philosophy

    of

    David

    Hume

    J

    META.MEDITATIONS:

    Studies

    n

    Descartes

    PLATO'S MENO:

    Texr

    and

    Criticism

    META.MEDITATIOT{S:

    Studies n Descartes

    edircd

    b1

    Alexander

    Sesonsfr'e

    nd

    Noel

    Flerrting

    UNIVERSITY

    OF

    CALIFORNIA'

    SANTA

    BARBARA

    Wadsuorth.

    Publish'ing

    Cornparyt'

    nc'

    BELMONT'

    CALIFORNIA

  • 8/10/2019 Cogito, ergo sum: Inference or performance? by Jaakko Hintikka

    3/16

    COGITO,

    ERGO

    SUM:

    INFERBNCB

    OR

    PERFORMANCE?*

    f aahoHinti,kha

    rv

    2n

    l.

    Cogito,

    crgo sum as a

    problem.

    The

    fame

    (some

    would

    say the no-

    toriety)

    of

    thc ntltgc cogito, ergo fl,rm makes

    one

    expect that scholarly

    industry hns

    147.

    ::

    Scc c.g.

    L. BlancheqLes ant4cddents u

    "Je

    pense,

    onc

    e

    suis"

    (Paris,

    1r)20);

    iricrrnc

    Gilson,

    Etudes ur Ie r6le de a

    pensie

    midi6,uale dns

    a

    Cogito,

    Ergo

    Sum

    5

    Augustine's

    anticipation.

    t cannot be denied,

    of

    course, hat

    the sim

    larities

    are

    striking.

    One may wonder, howevcr,

    whether they are

    a

    there

    is

    to the matter.

    Perhaps

    here are also dissimilarities

    betwee

    Descartes

    nd

    Augustine

    mportant

    enough o

    justify

    or at least o

    ex

    plain

    the

    one's reluctance

    to acknowledge

    lrc cxtent

    of

    the

    other

    anticipation.

    But we cannot

    tell whether

    thcrc is more ro

    Descarte

    cogito,ergosum han there s to St. Augustinc's irrilar argumentbe

    fore

    we

    can ell exactly

    what

    there s to the

    cogittt:lrgrrmcnt.

    If

    there are important

    differences

    betwccn

    l)cscartes and

    hi

    predecessors,he

    questionwill alsoarise

    whcthcr

    sonlc

    of

    thc

    anticipa

    tions

    are

    closer han

    others.

    For instance,

    Descartcs

    orrkl have

    oun

    the

    principle

    n St.

    ThomasAquinasas

    well as

    n

    St. Augustine.

    Which

    of

    the

    two

    saints omes

    loser o

    the cogito, ergo

    sum?

    3.

    What

    is the relation

    of

    cogito ta sum?

    Whnt

    kind

    of topica

    questionsdoes

    cogito, ergo

    sum

    give

    rise

    to?

    Onc

    of rlrc rnost

    m

    portant

    questionss undoubtedly

    hat

    of

    the logical

    orrrr

    of

    l)cscrrrtc

    inference.

    s it a

    formally valid inference?

    f not, wh:rc s krgical

    wrong

    about tl

    But there

    s an even

    more fundamental

    uestion

    lrlul tltcsc.

    )oc

    Descartes's

    ictum really

    express n inference?

    Thrrt it tkrcs s sug

    gestedby the

    particle

    ergo.

    According to Descartes, owcvcr, lry

    sry

    ing cogito,

    ergo sa.m e

    doesnot logically

    (syllogisticrlly)

    tlctlucc

    szr

    from

    cogito but

    rather

    perceives

    ntuitively

    ("by

    ^

    sirnplc lcf of nrcn

    tal vision")

    the self-evidence

    f

    sum3

    Similarly,

    Dcscartcs

    r.crrsionr

    says hat

    one'sown

    existences

    ntuitively obviouswithorrr

    Irringing

    n

    cogito

    asa

    premise.a

    ometimes'he

    ntimates

    hat

    his

    "first

    llrirrciplc"

    really

    the

    existence f his

    mind-and not the

    principlc

    ro$ittt,

    crl4

    sum,by

    means

    f

    which

    this existence

    s

    apparently

    dcdrrce

    l.b

    )nt.chc

    formulates he cogito

    principle

    Ls

    ego cogitansexisto

    withorrt

    rrsirrg

    he

    word.ergo

    at all.6

    But if it is true

    that the

    Cartesian

    ictum does not

    cxprcss n

    inference,

    equally

    perplexing

    questions

    re bound to

    arisc. Nor orrly is

    SCEuttres

    e Descartes,

    ublished

    by

    C,

    Adam and P. Tannery

    (1, tris,

    ttr)7

    1913),

    VII,

    140;

    The Philosofhical Worhs

    of Descartes,

    rans.'by ii. S. llulrlnn

    and

    G. R. T. Ross

    (London,

    1931),

    I, 38. In the sequel,

    lrcse'crlitionr rvill

    lrc

    referred to as AT and HR,

    respectively,with

    Roman-numerals cferrirrg to

    vol-

    umes.Normally I

    shall

    not

    follow Haldine and Ross's

    ranslation,howcvci'; I slrtl

    make use of the existing ranslations

    notably

    of those

    by N, I(ernp Srrritlr

    rrrl by

    =rather

  • 8/10/2019 Cogito, ergo sum: Inference or performance? by Jaakko Hintikka

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    52

    Meta.Meditations:

    Studies

    n Descartes

    the

    particle

    ergo then

    misplaced;

    he word

    cogito is likewise out of

    place

    n a sentencewhich only serves

    o

    call

    attention

    to

    the

    self-evi-

    denceof sum.

    But

    is

    the

    word cogito perhaps

    calculated o express

    he

    fact that

    thought is needed or

    grasping

    ha;t

    sum

    is

    intuitively evident?

    Was it

    perhaps

    an ndication of the

    fact

    that

    intuition was

    not for Descartes

    n

    irrational event but an act of

    the thinking mind, an

    "intellectual

    intui-

    tion," as t hasbeenaptly expressed??ven f

    this is

    part

    of

    the mean-

    ing of the word, the

    question

    will

    remain

    why Descartes

    wanted to

    stress he fact in connection rryith

    this

    particular

    insight.

    The

    same

    point

    would equally well apply

    to most

    of

    the other propositions

    of

    the Cartesiansystem;

    and

    yet

    Descartes

    does

    not

    say,

    for example,

    cogito, ergo Deusert n the way

    he

    says

    ogito,

    ergo sum.

    Clearly the word cogito

    must havesome

    urther

    function in Des-

    cartes's

    entence.

    ven if the sentence

    did not express

    syllogistic

    in-

    ference, t expressed omethingsufficiently

    like

    an

    inference

    to

    make

    Descartes all his

    sentence

    reasoning

    ratiocinium),8

    refer

    to exPress-

    ing it as nferring

    (inferre),s

    and

    call

    sum a conchtsion

    conclusio).1o

    As Martial Gueroult has trenchantly summedup the problem: "lo

    Descartes

    se refuse ) consid6rer e Cogito

    comme

    un

    raisonnement.

    .

    . . 2" Pourquoi s'obstine-t-il

    alors au moins

    trois reprises

    Inquisitio

    aeritatis,

    Discours,Principes)

    pr6senter

    e Cogito

    sous

    a forme

    qu'il

    lui d6nie?"11

    Since he word

    cogi.to

    s

    not dispensable

    nd since

    t is not

    iust

    a

    premise

    rom which the

    conclusionsum

    s deduced,

    he

    relation

    of

    the

    two

    becomee

    problem. One

    of

    the

    main objectives

    of

    this

    essay

    s to

    clear

    up their relation.

    4.

    Cogito, ergo sum as

    a logical nf

    erence,But can

    we be sure

    hat

    Descartes's

    ictum does not express

    a logical

    inference?

    n many

    re-

    spects t seems lausible o think that it does. ts logical form seems

    quite

    easy o define. n

    the sentence

    I

    think"

    an individual

    receives

    an

    attribute; or a modern

    ogician t is

    therefore

    of the form

    "B(a)."

    In

    the sentence I

    am," or "I

    exist," this

    same ndividual

    is

    said to

    exist.

    ?

    L.

    J.

    Beck,

    The Method of Descartes

    (Oxfoid,

    1952), ch.

    iv.

    8

    AT

    X,

    523;

    HR

    I,

    324.

    e

    AT VII,

    352;HR 11,207;

    f

    '

    AT

    III, 248.

    ToPrincipid

    philosophiae

    ,9; AT VIII' 7;

    HF.1,222; cf.

    AT II, 37, and

    AT

    v,147,

    11

    Martial

    Gueroult,

    "Le

    Cogito et

    la

    notion

    'pour

    penser il faut 6tre,"'

    Cogito,

    Ergo Sum

    53

    How

    can one represent

    such

    a sentence ormally?

    If

    Quine

    is right in

    claiming

    hat

    "to

    be is to be

    a valueof a bound

    variable," he

    formula

    "

    (Ex) (x

    =

    4) serves

    he

    purpose. nd evcn f hc s not

    right in

    genera

    in

    this

    particular casehis

    claim is obviously

    itrstified:

    "4

    exists"and

    "there exists

    at least

    one ndividual

    identical wirh a" are

    clearly synon-

    ymous. Descartes's

    ictum

    therefore seems o bc

    concerned

    with

    an

    implication

    of

    the

    form

    (1) B(a) = (Ex) ( r= a) .

    Descartes

    erceiveshat he

    thinks; hence

    he obtnins hc

    prcrniseB(a).

    If

    (l)

    is true,

    he

    can vse modus

    ponens

    o

    corrclrrtlc h;rt he

    exists

    Those who

    want to

    interpret the

    Cogito as a logicnl irrfcrcnce

    may

    now

    claim that

    (1)

    is in fact

    true, and even ogicnlly

    provnblc;

    or

    is

    not

    B(a)>

    (Ex)(x=a&B(x))

    a

    provable

    ormula

    of our lower

    functional calculi?

    Arrrl docs

    nor

    this

    formula

    entail

    (l)

    in

    virtue of

    completelyunproblcrrrnric

    lirrciplcs?

    t

    may seem hat an affirmative nswermust be givcn t

  • 8/10/2019 Cogito, ergo sum: Inference or performance? by Jaakko Hintikka

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    54

    Meta.Meditations:

    Studies

    in Descartes

    But even

    f we

    make

    his

    allowance,

    here remain

    plenty

    of difi-

    culties.

    As we

    saw,

    Descartes

    ometimes

    enies

    hat in

    ti"

    cogito

    ^rgr-

    ent sum

    is

    deduced

    .rom

    cogito.

    But

    on the

    view

    we are

    criticizing

    the argument

    s

    a deduction.

    The view

    is herefore

    unsatisfacrory.

    It

    is also

    unsatisfactory

    because

    t does

    not

    help

    us to

    unierstand

    the

    role of

    the

    cogito

    argument

    n

    the

    cartesian

    system.

    n so far

    as

    I

    can

    see, t docs

    not,

    for

    example,

    help

    us to

    appreciate

    he

    conse-

    quences

    Descartcs

    wantcd

    to draw

    from

    his first

    and

    foremost

    nsight.

    The gravcstobjcction,however, till remainso be made. t may

    be_shown

    hat thc

    provabiliry

    of

    (l)

    in the

    usual

    systems

    f functional

    calculus

    (quantificrtion

    theory)

    has

    nothing

    to do

    with

    the

    question

    whether

    thinking

    crrtails

    cxisrence.

    n attempt

    to interpret

    Deicartes's

    argument

    n tcrrns

    of the

    provabfity

    of

    (l)

    is thereforl

    bound

    ro

    re-

    main

    fruitlcss.

    By this

    I

    mcnn

    the following:

    if

    we have

    a closer

    look

    at the

    qFstems f

    logic

    irr

    which

    (l)

    can

    be

    proved,

    we

    soon discover

    that

    they

    arc based

    on

    imporrant

    existential

    presappositions,

    s have

    else-

    where

    called hem.tn

    fh.y

    make

    more

    or les

    tacit use

    of the assump-

    tion

    that

    all thc

    singular

    erms

    with

    which

    we have o deal really refir

    to

    (designatc)

    s.nrc

    actually

    existing

    ndividual.l'

    In our

    example

    his

    amounts

    o

    nssuriling

    hat

    the

    term

    which replaces

    n

    (1)

    muslnot

    be

    mpty.

    But

    sincc he

    term

    in

    question

    s

    "I,"

    this

    is

    just

    another

    way

    of

    saying

    hnt

    I

    exist.

    t turns

    out,

    therefore,

    ghat

    we in

    fact

    decided hat

    the

    sentence

    I exist"

    is true

    when

    we decided

    that

    the

    sentence

    I

    think"

    is

    of

    the

    form B(a)

    (for

    the

    purposesof the

    usual

    systems

    of

    functional

    loglc).ls

    That

    we

    were

    then

    able

    to infer

    (Er)

    (x

    =

    a)

    from

    B(a) is undoubtedly

    rue, but

    completely

    beside

    he

    point.

    .

    It

    is

    lxrssible

    o

    develop

    a

    system

    of logic

    which

    dispenses

    ith

    thc

    cxistcutial

    presuppositions.lT

    f in

    such a

    iystem

    we

    could infer

    "I

    exist" fronr "I rhink"-i.e. (Er) (x = a) from B(a)-it would be

    r{

    In

    "llxistential

    Presuppositions

    and

    Existential

    Commitments,,,

    foarnal

    of

    Phllotophy,

    LVI

    (l9t9),

    tzs-ijl.

    Itr

    All the

    singular

    terms

    (e.g.

    lirmes

    or

    pronouns)

    which

    in

    an application

    mry bo nubstit-uted

    or

    a free individual

    variable

    are assumed

    o

    do

    soi iod as

    a

    conlc(llrcncc nll

    the free

    individual

    variables

    have

    to behave

    like

    singular

    rerms

    which

    rcnlly

    posscss

    reference

    or

    "bearer."

    vulearlv-,teferend').

    ttt(if.

    Leibniz'

    incisive

    remark:

    ',And

    to

    iw i think,

    theiefore

    I

    ow.

    ls not

    propcrly

    to provc

    exisrence

    by

    thought,

    since

    to'think

    and

    to bi ttrintinc

    is

    rhe

    crnrc

    rhirrgi

    nnd

    to say, Iam

    thinking,

    is

    already

    to

    say, / arrz,,

    Nouaeaui

    Essais,

    u. by A.

    (i.

    l ,nngley

    La

    Salle,

    U.,1949),IV,

    7, ec.7).-

    lTSrrch

    Cogito,

    Ergo

    Sum

    highly relevant to

    the

    question

    whether thinking

    implies existence

    Descartes's ense.

    ut this we cannot

    do.

    The

    truth of

    a

    sentence

    f t

    form

    (1)

    turns entirely

    on existential

    presuppositions.

    f

    they are

    giv

    up, the

    provability

    of

    (1)

    goes

    by

    the

    board.

    My

    point

    may

    perhaps

    be

    illustrated

    by

    meansof

    an exam

    consrructed or us

    by

    Shakespeare.

    amlet did

    think a

    great

    ma

    things;

    does t follow that he existed?

    5, Descartes'semptation In spite of all this, tl'rcrcare passag

    Descarteswhich seem o suppoft the interpretation undcr

    criticism

    do

    not

    want

    to

    deny

    that it

    expresses

    ne of. hc thirrgs

    )escartes

    h

    more

    or

    lessconfusedly n mind when

    he fbrmuhtcd lris famous

    d

    tum. But it is important

    to realize hat this interprctntion

    is dcfcctive

    important respects. t does not

    help

    to elucidatc

    n nrry way

    somc

    Descartes'smost explicit and most careful

    formulations. It is

    at bes

    partial

    interpretation.

    One can seewhy

    some nterpretation like thc onc wc

    ltnvc

    bc

    criticizing attracted fi"r""tt"r. It

    gave

    him what

    must

    hnvc scctnc

    very usefulway of defending is own doctrinesand of silcncingcr

    cism. He could always

    ask:

    How can it possib ly

    be tmc of sornc

    that he thinks unless

    e exists?

    nd if

    you

    challenge hc prcrrrisc

    h

    he s thinking

    (why

    cannot he all-powerful

    malin

    gtnic

    nttl

  • 8/10/2019 Cogito, ergo sum: Inference or performance? by Jaakko Hintikka

    6/16

    56

    Metu-Meditations;

    Studies

    in

    Descartes

    Did

    Descartes

    earize

    hat

    it

    is

    misguided

    o

    represent

    his

    insight

    n

    the

    wav

    we

    hrl:

    b:"-tt

    air""rrr"gi'rt

    is

    very

    diffcurt

    to

    ter.

    cer-

    ainty

    e

    .".,

    ,:11r:g

    ;

    {ry.

    ii"t

    r.".,

    ..o

    h^u"

    "ii"dl

    r,o*.u.r,hat

    on

    this

    interpretation

    the'""riairu'"r

    his

    argument

    depends

    essen-

    ially

    on

    existential

    pt.*pp"rii#.

    i.,

    when

    he

    tried

    to present

    his

    f;111il:T::ff::,r,,

    n;dedu;;;"-

    ,

    ,g.o_.rricar,,

    ronir,

    e

    uied

    ,,uzecan;;;"t{id:{d"..}:',-t*,il11',X;;*:{,;if

    ",iUy:;

    ntis)" AT vII, 16.6; -fl lt,-iii.?r,-i,

    ,r"r._ent

    s

    an

    he

    more

    e-

    arkabre

    since

    t

    prima.

    acie'.rtirr"ai.r-

    whar

    Descarres

    ays

    n

    the

    hird

    Meditation

    ibout,t;;;

    .

    .".-"l"rro*.0

    only

    in

    themsitves,

    and

    ot

    as

    referred

    :"

    ,:T.

    -_other

    hing,,,

    namely

    if,r,

    ,,iilf

    cannoq

    trictry

    speakins,

    e..farse."

    t;rr;;";"dicts

    the

    plain

    facl

    rhar

    we

    an

    think

    of

    (nientaty

    """ria.rj"i.iJ-"s,

    or

    princi

    Hamret,

    u.irhout

    hereby

    commiming

    ourselves

    "

    ."irr"i"i"g

    that

    they

    exist.

    he

    fact

    arso

    emains

    att",

    o.r"".resresorted'to

    the

    interpreta-

    ion

    we

    have

    been

    .crilicjzing

    ffiry

    in

    his

    more

    popurar

    writ-

    ngs'

    As

    Guerourt

    noticed,

    n.

    a?.,

    ""a'r.ro*

    to

    it

    in

    the

    Meditationes.

    is

    most

    explicit

    usg

    o{

    ii

    o."ul,

    io"n))nrr"n" de la a6rit6,in a dia_

    oguewhose idactic

    "t

    rt*i-irr'ffi

    particurarry

    -p-nrrir"a

    uy

    rnesr

    assirer.le

    .r""ri.Jr

    *rrr

    "-li"r

    rr*r"r*ii"r;fTh:

    cogito

    rgumenr,

    otabty

    hose

    n

    tn"

    uiiii)ti""*

    .;;-;ri*;,piiioropuo,

    eem

    o

    presuppose

    difierent

    "r.rpro"rlro

    or

    n"

    ".fi,rri"o .,"',.

    -

    6'

    Existentiar

    inconsistency.

    In

    order

    to

    understand

    this

    second

    nterpretation

    of

    the

    Cogito

    *"

    n"""

    ;;;":

    a

    closer

    rorr.

    ",

    ,i"

    rogi"

    f

    Descart.s's

    amed

    argument.

    Descartes,s

    ormurations

    in

    the

    Aledita_

    iones

    and,

    lsewhere

    TSSgst

    hat

    his

    ,"roti

    _"y

    u"

    "*p*rr.J

    iy'r"yinghat

    it

    was

    mpossibt"

    nit:ni-

    *

    a'."yit,

    ,rrrt.nc".

    one

    w^y

    irtwhich

    ,?"#::,'"".',:lX,i::-diF.t'.'iii.:"r.nr,*,"iilliebeen

    n.r"i*.J-n;r;;1tt-"ot

    exist'"

    As

    a

    preliminary

    o

    o*-r*ay

    or

    tt..t,,,"i..;ffi

    f

    ;T:q::::::;::+;:?ff

    l*i;S:Ll[

    ould

    not

    have

    maintai".a'rrra

    i"rr*

    ;til*

    our

    o

    be

    closely

    erated

    o

    the

    easons

    hy

    he

    asserted

    r,"

    fo._.i

    iir

    "_

    rigt

    t.

    What,

    hen,

    are

    h.r.

    r."rorr;f

    ##;.reral

    characteristic

    f

    the

    entence

    De

    Gau'e

    does

    not

    .*irr"

    -"L.rr

    it

    awkward

    or

    De

    GauIIe

    o

    asse*

    tl2o

    I

    shall

    uy

    to

    formulrt.

    iii,

    g"rr.r"l

    "h"r""terisJc,ny

    Cogito,

    Ergo

    Sum

    57

    sayine

    that

    it

    is

    existentially

    nconsistent

    or

    De

    Gaulle

    to

    assert

    (to

    ;;;i

    ini,

    ,."..n"e.

    The

    notion

    of

    existential

    nconsistency

    may

    be

    a"n"'.a

    as

    follows;

    let

    p

    be

    a sentence

    and

    a

    a

    singular

    term

    (e'g'

    a

    name,

    a

    pronoun,

    or

    a

    definite

    description)'

    We

    shall

    say

    that

    p

    is

    existentiaity

    nconsistent

    or

    the

    persoireferred

    to

    by a

    to

    utter

    rf

    znd

    only

    if the

    longer

    sentence

    (2) "P;

    and

    4

    exists"

    is

    inconsistent

    in

    the ordinary

    sense

    f

    the

    word)'

    In

    order

    to-avoid

    our

    own

    obiections

    we

    must

    of

    "oottt

    require

    thlt

    thc

    notion

    of

    ordi-

    nary

    inconsisrency

    which

    is

    used

    n

    the

    definition

    involves

    no

    existen-

    ;i;i'p;;pp;sitiois.

    Provided

    that

    this

    is

    the

    casc,

    wc

    may

    write

    (2)

    more

    formally

    as

    (2)',

    "p

    &

    (Ex)

    (t

    =

    a)-"

    (As

    the informed

    reader

    has

    no

    doubt

    already.^1ntiT1'^Ye

    should

    really

    use

    quasi

    uotes

    nstead

    f

    double

    quotes

    n

    (2)

    and

    (2)")

    -*

    'A

    ;ti;"i

    tlforr""t".ion

    of

    the

    definition

    shows

    hnt

    thc

    notion

    of

    existentialnconsistencyeally formulates general cilsotlwlty ccrtain

    ,i"r"-.r,*

    are mpossidle

    o

    defend

    although-the

    sentcnces

    y mcnns

    of

    *tti.n

    they

    are

    m"de

    m"y

    be

    consistent

    nd

    ntelligiblc'

    nsentl.:-f

    lty-

    ing

    that

    1i;

    is

    incorrsistJnt,

    e

    could

    have

    said

    hat

    p

    cntrrils

    d

    docs

    ,ro-t

    "*irti

    (without

    the

    use

    of

    any

    existential-presupposirions

    lut

    otherwise

    n

    the

    ordinary

    sense

    of entailment)'

    Uttering

    stlcll

    il. scn-

    tence,

    ,

    will

    be lr"ry

    a*k*"rd

    for

    the

    bearer

    of

    a: it

    mcnns

    rtnlrrlrg

    a

    ,r"a"-"rr,

    which,

    if

    tme,

    entails

    hat

    its

    maker

    does

    not

    exist'

    It

    is mportan

    to

    rcalize

    hat

    the

    ills

    of such

    statuments

    nnnot

    bc

    blamed

    on

    the

    sentences

    y means

    of

    which

    they

    are

    madc'el.

    n

    fnct'

    the

    notion

    of

    existential

    ntonsistency

    cannot

    be applied

    nt

    nll

    ttt

    scn-

    tences.

    As we defined he notion, it is a relation between scntenccond

    21

    t mav

    be wonh

    while

    to recall

    here

    the

    distinction

    betwcctl

    0

    ficlltctlcci

    "o

    o*.r"r"i,?ii'r,-"i"-.r..

    A

    sentence

    s

    of

    course

    a

    grammaticnl

    .cnlity

    tltrtt

    i"uoi"a,

    no

    reference

    to

    any

    particular

    utterer

    or any

    particular

    tlmc

    ()t

    lltttrtlll('c'

    An

    utterance

    , ,r,

    "u"tJ-?l

    "p"L"rt-""t1

    that

    may

    6e'specified

    by.spccifyirrg

    tlre

    ;;J;;ce,

    the

    speaker,

    nd

    the

    occesion

    n'which

    he

    makes

    his utterrrrrcc'

    --':-

    U*;""1

    or

    i""irtiirr"

    *tt."tt""'

    (with

    prima-facie

    fact-strtitrg

    intcnt)

    "r.

    ,*iJ

    "*"-pt",

    "f

    tiiiiiriri.

    (lt

    "

    term

    doeinot

    seem-especially

    ho'py,

    lrttt

    i';hillt;;;f

    i;;;"-il

    ;ppears

    to

    be

    rather

    widespread.)

    A

    statctttcttt

    s rtt

    event

    (an

    act)

    occurring;;[;;;;"out

    "o"**t'

    Usirally

    it is a sPecctr'nt:t

    'f

    n

    on

    that.

    For

    our

    purposes

    a st{tcnrcrrt

    rr'y

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    a

    singular

    erm

    rather

    than

    a

    property

    of

    sentences.

    he

    notion

    of

    existential

    nconsistency,

    however,

    can"often

    be

    applied

    to

    statements

    in a.fairly

    narural

    sense.

    n

    order

    to

    specify

    "

    ,tii"rn"rrt

    we

    have

    to

    specify (inter

    alia)

    the

    sentence

    ttered (t

    y,

    q)

    and

    its

    utterer.

    If

    the

    latter

    refers

    to himself

    by

    means

    of the

    singni"r

    term

    & when

    he

    makes

    his

    statemenr'

    we

    may

    say

    that

    the

    notiori

    appries

    o the

    statement

    f

    and

    only

    if it

    applies

    o

    4

    in relation

    o &.

    A

    simple

    example

    will make the situation crear.The sentences

    "De

    Gaulle

    does

    not

    exist"

    and

    "Descartes

    does

    not

    exist"

    a.re

    not

    in-

    consistent

    or

    otherwise

    objectionable

    any

    more

    than

    the

    moot

    senrence

    "Homer

    does

    not

    exist."

    None

    of

    them

    is

    farse

    for logicar

    rasons

    alone.

    whar

    would

    be

    (existentiaily)

    inconsisrenr

    would

    be

    the

    at-

    tempt

    of a

    certain

    man

    (De

    Gaulle,

    Descartes,

    r

    Homer,

    respectively)

    to

    use

    one

    of these

    sentences

    o

    make

    a

    $atement.

    uttered'by

    some-

    body

    else,

    he

    sentences

    n

    question

    need

    not

    have

    anything

    #o'g

    o,

    even

    strange

    about

    hem.

    It lies

    close

    at

    hand

    to

    express

    his

    important

    feature

    of the

    no-

    tion

    of

    existential

    nconsistencyby

    me"ns

    of'a

    term

    which

    has

    ecently

    "ligygd

    wide currency. The inconsistency (absurdity) of an existen-

    tially

    inconsistent

    statiment

    can

    in

    a

    sense

    e

    said

    ao'b"

    of

    [r4or*n-

    tory

    (pefiormative)

    character.

    t depends

    n

    an

    act

    or

    "performance,,,

    nlmely

    on

    a certain

    person's

    act

    of-uttering

    a

    sentence'(or

    of other-

    wise

    making

    a statement);

    t does

    not

    depen"cl

    olery

    on

    the

    means

    used

    for

    the

    purpose,

    hat

    is,

    on the

    ..rrt"rr""

    which

    is"

    being

    uttered.

    The

    sentence

    s

    perfectly

    correct

    asa

    sentence,

    ut

    the

    ,tt"tript

    of a

    certain

    man

    to

    utter

    it

    assertively

    s curiorr-sly

    ointless.

    f

    one

    of these

    days

    should

    eadin

    the

    morning

    paper,

    "T/hele

    s

    no

    De

    Gaulle

    any

    more,,,

    could

    understand

    what

    is

    belng

    said.

    But

    no

    one

    who

    knows

    charles

    de

    9"*":""11 *tp

    be-ing

    puzzled

    by

    these

    words

    if they were utteredby De Gaulle himself;

    he

    only

    way

    of

    making

    sense

    f ihem

    would

    be

    to

    give them

    a nonliteral

    meaning.

    -

    we

    can

    here

    see

    how

    the

    existential

    nconsistency

    of De

    Gaulre,s

    fictional

    utterance

    (as

    well

    as

    the

    inconsistency

    of

    oiher

    existentially

    inconsistent

    statements)

    mani.fests

    tself.

    Normally

    a

    speaker

    wants

    his

    hearer

    to believe

    what

    he

    says.

    The

    whore

    "l"ngo"g6-game',

    of fact-

    stating

    discourse

    s

    based

    on

    the

    assumption

    hai

    ttrls

    ii normally

    the

    ""::.By:

    nobody

    can

    make

    his

    hearer

    believe

    hat

    he

    does

    nor

    ""lrt

    Uy

    telling

    him

    so;

    such

    an

    anempr

    s rikely

    to

    have

    he

    opposite

    esult.

    The

    Cogito,

    Ergo

    Sutn

    59

    Iomrtically"

    means

    here

    something

    ike

    "{91

    melely

    logical

    reasons"')

    ,l'his

    destirctive

    effect

    is

    of

    couise

    conditional

    on

    the

    fact

    that

    the

    Ircarer

    nows

    who

    the

    maker

    of

    the

    statement

    s,

    that

    is,

    that

    he

    identi-

    lics

    he

    speaker

    s

    he same

    man

    he

    uttered

    sentence

    s

    about'

    In'a

    special

    case

    a self-defeating

    ttemPt.of

    this.kind

    can

    be

    rnade

    withoirt

    saying

    or

    writing

    anything

    or.

    doing

    anything

    to,TpT-

    ,,f,i..

    f"

    iryittg

    ,6 tri"t

    "

    others-beliive

    something

    must

    normally

    do

    something'wliich can be heard or seen

    or

    felt'

    But

    in

    trying

    to-

    make

    myself

    bJlieve

    something

    here

    is

    no

    need

    to

    say

    anything.aloud

    or to

    write'anything

    on p"p"i.

    The

    performance

    hiough

    w6ich

    existential

    inconrirtlt"y"r.ir.,

    can in

    this

    case

    be

    merely.nl.lttcmlt

    to

    think-

    nlor"

    "".oritely,

    an

    attemPt

    to

    make

    oneself

    bclicvc-that

    one

    does

    not exist.22

    This

    transition

    from

    "public"

    speech-acts

    o

    "privfttc"

    thought-

    acts,

    however,

    does

    not

    afiect

    the

    essential

    eatures

    of

    d-rcir

    ogic.

    The

    reason

    why

    Descartes's

    ttempt

    to

    tbink

    that

    he docs

    n

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    In

    a

    frequently

    occurring

    special

    case

    such an

    omission

    s not

    only natural

    but almost

    nevitable.

    t is the

    case n

    which the

    speaker

    refers

    to

    himself

    by

    means

    of the

    first-person

    singular

    prorroo'n

    ,I."

    This

    pron_ounnevitably

    refers

    to

    whoever

    happens

    o

    -be

    speaking.

    The

    specification

    inconsistentor

    . . . to

    utterl'therefore."i,tc"r

    to

    the-tautology

    "inconsistent

    or

    whoever

    happens

    o

    be speaking

    o ut-

    ter," and-may

    herefore

    be

    omitted

    almost

    always.

    n

    a special

    case, he

    notion of existential nconsistencymay therefore be definedfor sen-

    tencessimpliciter

    and

    ot

    only

    for ,"nt"n".,

    thought

    of

    as being

    ut-

    tered

    by

    some

    particular

    speaker.

    These are

    the

    sentences

    hich

    con-

    tain

    a first-person

    singular

    pronoun.

    The

    existential

    nconsistency

    of

    such

    a sentence

    will

    mean

    that

    its

    utterer

    cannot

    add

    "and

    I exist"

    without

    contradicting

    himself

    mplicity

    or

    explicitly.

    -

    There

    are

    purposes,

    owevel,

    for

    whiCh

    t may be

    misleading

    o

    forget

    the

    specification.

    Forgetting

    it

    may be dangerous

    ince t lEads

    one

    to

    overlook

    the

    important

    similarities

    which obtain between

    exis-

    tentially

    inconsistent

    entences

    nd

    existentially

    nconsistent

    tatements.

    In a

    perfectly

    good sense,existentially nconsistentsentences re alr

    right

    as

    sentences.

    hey

    may

    be

    said to

    be consistent

    and

    sometimes

    even

    significant (e.g.

    when

    they

    occur

    as

    parts of more

    complicated

    sentences).

    According

    to

    their

    very definition,

    existentially-

    ncon-

    sistent

    sentences

    re

    not

    so much

    inconsistent

    as

    such

    as

    absurd for

    anyone

    o utter.

    Their

    (existential)

    nconsistency

    s therefore

    of

    per-

    formatory

    character

    exactly

    in the

    samesense

    as hat

    of the existen-

    tially

    inconsistent

    tatements.

    he

    only difference

    berween he

    two lies

    in

    the fact

    that,the

    latter

    are inconsiitent

    for some

    particular man to

    make

    while

    the former

    are

    inconsistent

    or anyone

    1o utter.

    The in-

    consistency

    of existentially

    nconsistent

    sentences

    means

    hat whoever

    tries

    to

    make

    somebody anybody)

    believe

    hem, by

    so doing,

    helps o

    defeat

    his

    own

    purpose.2s

    uch an attempt

    may

    take the form

    of utter-

    ing

    the

    sentence

    ssertively;

    or it may

    take

    the form

    of trying to

    per-

    suade

    neself

    of the

    truth

    of the

    sentence

    n

    question.

    In

    the

    same

    way

    as

    existentially

    inconsistent

    sentences

    defeat

    themselves

    hen

    they

    are

    uttered'or

    thought

    of, their

    negations

    erify

    themselves

    when they

    are

    expressly

    uttered

    o,r

    otherwise

    professed.

    such

    -sentences

    may

    'therefore

    be

    called

    existentially

    self-verifying.

    ,,I

    Cogito , I l rg ,o

    Sun

    6

    8. Descartes'snsight.

    Now

    rvc

    ltrtvc rt 'rtr ' l t t ' .1

    r

    point

    where

    w

    cnn express

    recisely

    he import

    of l)csc:tt ' t t 's's

    rrsiglrr

    or

    nt least o

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    been

    ess

    misleading

    or

    Descartes

    o

    say,

    "I

    am n

    that I

    think,,,

    or

    .,By

    thinking

    I

    perceive

    my

    existence,"

    han

    to say,

    ',I think, therefore

    I

    am."

    It

    may

    be worth

    noting

    that

    one of

    our formulations

    was

    closely

    anticipated

    by

    St. Thomas

    Aquinas

    when he

    wrote:

    ,,Nullus

    pot.Jt

    cogltare

    se non

    esse um

    assensu:

    n hoc

    enim

    quod cogitat

    aliquid,

    percipit

    se esse" De

    aeritate,

    X, lZ,

    ad

    7).

    The

    peculiarity

    of-this

    relation

    explains

    Descartes's

    acillation

    n expressing

    t in that'he

    some-

    times

    speaks

    f the

    Cogito

    as an inference

    and

    sometimes

    s a rcaliza-

    tion of the intuitive

    self-evidence

    f

    its

    latter

    half.

    Similarly

    we

    may now

    appreciate

    he function

    of

    the

    word

    cogito

    in

    Descartes's

    entence s

    well

    as his

    motives n

    employing

    it. It

    serves

    o express

    he

    performatory

    character

    of Descartes's

    nsight; it

    refers

    to

    the

    "performance" (to

    the

    act

    of thinking)

    through

    -tticn

    he

    senrence

    I

    exist"

    may be

    said o

    verify

    itself.

    Foi this reaJon.

    t has

    a most

    important

    function

    in Descartesi,

    .rrt"n"".

    It cannot

    t" ,"-

    placed by

    any

    arbitrary

    verb.

    The

    performance

    (act)

    through

    which

    the

    existential

    self-verifiability

    is

    manifested

    cannot be

    any rbiuary

    human

    activity,

    contrary

    to

    what

    Gassendi laimed.

    t

    cannot be an act

    of walking or an act of seeing. t cannot even be an instanceof arbi-

    trarymental

    activity,

    say

    of willing

    or

    of

    feeling.

    It

    must be

    just

    what

    we said

    t is:

    an attempt

    to think

    in the

    sense

    f making

    myself believe

    (an

    attempt

    to

    think

    cam

    assensu,

    sAquinas

    put

    it)

    that I do not

    exist.

    Ffence

    Descartes's

    hoice

    of the

    word cogito.

    This

    particular

    word is

    ncit

    absolutely

    ndispensable,

    owever,

    or

    the act

    of ihinking

    to

    which

    it

    refers

    could

    also

    be called

    an

    act

    of doubting;

    and Des-aftes

    does

    admit

    thatJris

    insight

    is

    also

    expressible

    y

    dubito, ergo

    sum

    (in

    Re-

    chercbe

    de a

    a6rit6,

    AT X,

    523;

    HR

    I,324;

    cf. alsoPrincipia

    philoso-

    phiae,I,7).

    But

    did

    I not say

    that

    the

    performance

    hrough

    which

    an exis-

    tentially self-verifying senrence erifies tself may aFo be an act utrer-

    ing itl

    Is this not

    incompatible

    with

    Descartes's

    use

    of the word

    cogito?

    There

    is

    no

    incompatibility,

    for Descartes

    says exactly the

    same.

    n his

    second

    meditation

    on first

    philosophy he

    says

    n so

    many

    words

    that

    the sentence

    I

    e{ist" is necessarily

    rue

    ,,whenever

    I uttef

    it

    or conceive

    t in

    my

    mind"-"quoties

    a

    me

    profertur, vel

    mente

    concipitur" (AT

    VII, 25;

    HR I, 150).26

    introspection)

    rather

    vague.

    Nor

    does

    Gueroult

    rearize

    hat

    the loeical

    aspect

    of

    Cogito,

    Ergo

    Sum

    The

    performatory

    character

    of l)cscnrtcs's

    irtsigltt

    PresuPPos

    cl'raracterisiic

    eature of

    his famous

    mcth(,(l

    of

    tkrttlrt which

    has

    fr

    quently

    been commented on

    in othcr

    colltcxls,

    l)csc:lrtcs's

    doubt

    do

    not consist n

    the

    giving

    up of

    all opiniorrs,

    rts t skcptic's

    tloubt

    mig

    Nor

    is it an attempt

    to iemove

    certaitr

    sltct'ilit'

    s()ttlccs

    of

    mista

    from our

    thinking, like Francis

    Bacon's.

    lt rttttottttts

    () lltl

    active

    tempt to think

    the contrary of

    what

    we ttsurtl ly

    rclicvc.

    ior

    this

    rea

    Deslartes

    could claim

    that in an

    importnnt

    lloittt

    tlris

    rrrtltc:r

    loctrina

    doubt

    of his defeats tself. A

    skeptic'spnssivc

    krttlrt

    'ottlt l

    ttcvcr

    do

    The performatory

    character

    of Dcscilrtcs's

    llrigllt

    is

    irr fnct

    p

    and

    parcel-of

    the

    general

    strategy

    of

    fuis

    rcdttrti()

    trl

    tltsrlrdrntt

    (

    perhaps

    ather

    projiectio

    ad absurdum.)

    of

    skcptit ' isrrr,

    l ' lris

    sl

    rltcgv

    6.onght out

    very welt

    by Richard

    Popkin

    in

    lris tttpor'l

    tnt

    .u,ol' l