Month: November 2005

  • Hobgoblin?

    Brian Davies is a professor of mathematics at King's College London.  In the December Notices of the American Mathematical
    Society
    , he claims that arithmetic may, for all we know, be inconsistent:

    "Gödel taught us that it is not possible to prove that Peano arithmetic
    is consistent, but everyone has taken it for granted that in fact it is
    indeed consistent.
        Platonistically-inclined mathematicians would
    deny the possibility that Peano arithmetic could be flawed.  From
    Kronecker onwards many consider that they have a direct insight into
    the natural numbers, which guarantees their existence. If the natural
    numbers exist and Peano’s axioms describe properties that they possess
    then, since the axioms can be instantiated, they must be consistent."

    "It is not possible to prove that Peano arithmetic is consistent"...?!

    Where
    did Gödel say this?  Gödel proved, in fact, according to a
    well-known mathematician at Princeton, that (letting PA stand for Peano
    Arithmetic),

    "If PA is consistent, the formula expressing 'PA is consistent' is unprovable in PA."

    -- Edward Nelson,
       Mathematics and Faith (pdf)

    Remarkably, even after he has stated correctly Gödel's result, Nelson, like Davies, concludes that

    "The consistency of PA cannot be concretely demonstrated."

    I prefer the argument that the existence of a model ensures the consistency of a theory.

    For instance, the Toronto philosopher William Seager writes that

    "Our
    judgement as to the consistency of some system is not dependent upon
    that system’s being able to prove its own consistency (i.e. generate a
    formula that states, e.g. ‘0=1’ is not provable). For if that was the
    sole basis, how could we trust it? If the system was inconsistent, it
    could generate this formula as well (see Smullyan, Gödel’s Incompleteness Theorems,
    (Oxford, 1992, p. 109)). Furthermore, [George] Boolos allows that we do
    know that certain systems, such as Peano Arithmetic, are consistent
    even though they cannot prove their own consistency. Presumably, we
    know this because we can see that a certain model satisfies the axioms
    of the system at issue, hence that they are true in that model and so
    must be consistent."

    -- Yesterday's Algorithm:
        Penrose and the Gödel Argument

    The relationship between consistency and the existence of a model is
    brought home by the following weblog entry that neatly summarizes a
    fallacious argument offered in the AMS Notices by Davies:

    The
    following is an interesting example that I came across in the article
    "Whither Mathematics?" by Brian Davies in the December issue of Notices
    of the American Mathematical Society.

    Consider the following list A1 of axioms.

    (1) There is a natural number 0.
    (2) Every natural number a has a successor, denoted by S(a).
    (3) There is no natural number whose successor is 0.
    (4) Distinct natural numbers have distinct successors: a = b if and only if S(a) = S(b).
    (5) If a property is possessed by 0 and also by the successor of every
    natural number which possesses it, then it is possessed by all the
    natural numbers.

    Now consider the following list A2 of axioms.

    (1) G is a set of elements and these elements obey the group axioms.
    (2) G is finite but not isomorphic to any known list of finite simple groups.
    (3) G is simple, in other words, if N is a subset of G satisfying certain properties then N=G.

    We can roughly compare A2 with A1. The second axiom in A2 can be
    thought of as analogous to the third axiom of A1. Also the third axiom
    of A2 is analogous to the fifth axiom of A1, insofar as it refers to an
    unspecified set with cetain properties and concludes that it is equal
    to G.

    Now, as is generally believed by most group theorists, the system A2 is internally inconsistent and the proof its inconsistency runs for more than 10000 pages.

    So who is to deny that the system A1 is also probably internally inconsistent! Particularly since Godel proved
    that you can not prove it is consistent (staying inside the system).
    May be the shortest proof of its inconsistency is one hundred million
    pages long!

    -- Posted by Krishna,
       11/29/2005 11:46:00 PM,
       at his weblog,
      "Quasi-Coherent Ruminations"

    An important
    difference between A1 (the set of axioms of Peano arithmetic) and A2 (a
    set of axioms that describe a new, unknown, finite simple
    group) is that A1 is known to have a model (the nonnegative integers) and A2
    is not known to have a model.

    Therefore, according to Seager's argument, A1 is consistent and A2 may or may not be consistent.

    The degree to which Seager's argument invokes Platonic realism is debatable.  Less debatable is the quasireligious faith in nominalism
    proclaimed by Davies and Nelson.  Nelson's own account of a
    religious experience in 1976 at Toronto
    is instructive.

    I must relate how
    I lost my faith in Pythagorean numbers. One morning at the 1976 Summer
    Meeting of the American Mathematical Society in Toronto, I woke early.
    As I lay meditating about numbers, I felt the momentary overwhelming
    presence of one who convicted me of arrogance for my belief in the real
    existence of an infinite world of numbers, leaving me like an infant in
    a crib reduced to counting on my fingers. Now I live in a world in
    which there are no numbers save those that human beings on occasion
    construct.

    -- Edward Nelson,
       Mathematics and Faith (pdf)

    Nelson's "Mathematics and Faith" was written for the Jubilee for Men and Women from the World of Learning held at the Vatican, 23-24 May 2000.  It concludes with an invocation of St. Paul:

    During
    my first stay in Rome I used to play chess with Ernesto Buonaiuti. In
    his writings and in his life, Buonaiuti with passionate eloquence
    opposed the reification of human abstractions. I close by quoting one
    sentence from his Pellegrino di Roma
    "For [St. Paul] abstract truth, absolute laws, do not exist, because
    all of our thinking is subordinated to the construction of this holy
    temple of the Spirit, whose manifestations are not abstract ideas, but
    fruits of goodness, of peace, of charity and forgiveness."

    -- Edward Nelson,
       Mathematics and Faith (pdf)

    Belief
    in the consistency of arithmetic may or may not be foolish, and
    therefore an Emersonian hobgoblin of little minds, but bullshit is
    bullshit, whether in London, in Princeton, in Toronto, or in Rome.

  • For St. Andrew's Day

    "The miraculous enters....
    When we investigate these problems, some fantastic things happen...."

    -- John H. Conway and N. J. A. Sloane, Sphere Packings, Lattices and Groups, preface to first edition (1988)

    The remarkable
    Mathieu group M24, a group of permutations on 24 elements, may be
    studied by picturing its action on three interchangeable 8-element
    "octads," as
    in the "Miracle Octad Generator" of R. T. Curtis.

    A picture of the Miracle Octad Generator, with my comments, is available online.

  • The Way of the Pilgrim,

    Part III:

     

    For the Birthday

    of C. S. Lewis

    The image “http://www.log24.com/log/pix05B/051129-Tao.jpg” cannot be displayed, because it contains errors.

    The Tao, Chapter I

    "The Chinese... speak of a great thing (the
    greatest thing) called the Tao. It is the reality beyond all
    predicates, the abyss that was before the Creator Himself. It is
    Nature, it is the Way, the Road. It is the Way in which the universe
    goes on, the Way in which things everlastingly emerge, stilly and
    tranquilly, into space and time. It is also the Way which every man
    should tread in imitation of that cosmic and supercosmic progression,
    conforming all activities to that great exemplar."

    -- C. S. Lewis in The Abolition of Man

    "In his preface to That Hideous Strength, Lewis says the novel has a serious point that he has tried to make in this little book, The Abolition of Man.  The novel is a work of fantasy or science fiction, while Abolition
    is a short philosophical work about moral education, but as we shall
    see the two go together; we will understand either book better by
    having read and thought about the other."

    -- Dale Nelson, Notes on The Abolition of Man

    "In Epiphany Term, 1942, C.S. Lewis delivered the Riddell
    Memorial Lectures... in.... 
    the University of Durham....  He
    delivered three lectures
    entitled 'Men without Chests,' 'The Way,' and 'The
    Abolition of Man.'  In them he set out to attack and
    confute what he saw as the errors of his age. He started by
    quoting some fashionable lunacy from an educationalists'
    textbook, from which he developed a general attack on moral
    subjectivism.  In his second lecture he argued against
    various contemporary isms, which purported to replace
    traditional objective morality.  His final lecture, 'The
    Abolition of Man,' which also provided the title of the
    book published the following year, was a sustained attack on
    hard-line scientific anti-humanism.

    The intervening fifty years have largely vindicated Lewis."

    -- J. R. Lucas, The Restoration of Man

  • The Way of the Pilgrim,
    Part II:
     
    Einstein's Orgy

    In a recent Edge article, "The Vagaries of Religious Experience," a Harvard psychologist, Daniel Gilbert,  quotes Einstein on his own religious vagaries:

    "(I
    had) a deep religiosity, which, however, found an abrupt ending at
    the age of 12. Through the reading of popular scientific books I soon
    reached the conviction that much in the stories of the Bible could
    not be true. The consequence was a positively fanatic orgy* of freethinking
    coupled with the impression that youth is intentionally being deceived
    by the state through lies. It was a crushing impression. Suspicion
    against every kind of authority grew out of this experience, a skeptical
    attitude towards the convictions which were alive in any specific
    social environment-- an attitude which has never again left
    me." (Autobiographical Notes, 1949)

    Gilbert adds,

    "Einstein's
    orgy* of freethinking forever changed our understanding of space and
    time, and the phrase 'Religion for Dummies' became, in the
    view of many scientists, a redundancy."

    Here is another Einstein quotation, from the paragraph in Autobiographical Notes following the paragraph quoted by Gilbert:

    "It is quite clear to me that the religious paradise of youth, which
    was thus lost, was a first attempt to free myself from the chains of
    the 'merely-personal,' from an existence which is dominated by wishes,
    hopes and primitive feelings.  Out yonder there was this huge
    world, which exists independently of us human beings and which stands
    before us like a great, eternal riddle, at least partially accessible to
    our inspection and thinking.  The contemplation of this world
    beckoned like a liberation.... The road to this paradise was not as
    comfortable and alluring as the road to the religious paradise; but it
    has proved itself as trustworthy, and I have never regretted having
    chosen it."

    Einstein
    describes "the road to the religious paradise" as "comfortable and
    alluring."  He might therefore have profited by the book saluted
    in the previous entry... a book that might be described, to adapt Gilbert's
    charming phrase, as "Religion for Dummies like Einstein."

    For an approach to the contemptible religion of Scientism that is more subtle than Gilbert's, see "Einstein's Third Paradise," by Gerald Holton, another Harvard savant.

    * In the original, the words "orgy of" appear in square
    brackets to indicate an interpolation by the editor, Paul A. Schilpp, a Methodist minister (pdf).  Einstein's own words were "eine geradezu fanatische Freigeisterei." 
    Gilbert's omission of the brackets indicates both the moral
    slovenliness typical of those embracing Scientism and the current low
    standards of scholarship at Harvard.  (Related material: The Crimson Passion.)

  • The Way of the Pilgrim,
    Part I:
     
    For John Bunyan's
    Birthday



    The image “http://www.log24.com/log/pix05B/051128-PilgrimsProgress12.jpg” cannot be displayed, because it contains errors.

    Click on picture to enlarge.

    "AS I walk’d through the wilderness of this
    world, I lighted on a certain place where was a Den, and I laid me down
    in that place to sleep; and as I slept, I dreamed a Dream. I dreamed,
    and behold I saw a Man cloathed with Rags, standing in a certain place,
    with his face from his own house, a Book in his hand, and a great
    Burden upon his back. I looked, and saw him open the Book, and read
    therein; and as he read, he wept and trembled; and not being able
    longer to contain, he brake out with a lamentable cry, saying What shall I do?"

    -- The Pilgrim's Progress, by John Bunyan


  • Holy Geometry

    What was "the holy geometry book" ("das heilige Geometrie-Büchlein," p.
    10 in the Schilpp book below) that so impressed the young Albert
    Einstein?

    "At
    the age of 12 I experienced a second wonder of a totally different
    nature: in a little book dealing with Euclidian plane geometry, which
    came into my hands at the beginning of a schoolyear.  Here were
    assertions, as for example the intersection of the three altitudes of a
    triangle in one point, which-- though by no means evident-- could
    nevertheless be proved with such certainty that any doubt appeared to
    be out of the question.  This lucidity and certainty made an
    indescribable impression upon me."

    ("Im
    Alter von 12 Jahren erlebte ich ein zweites Wunder ganz verschiedener
    Art: An einem Büchlein über Euklidische Geometrie der Ebene, das ich am
    Anfang eines
    Schuljahres in die Hand bekam.  Da waren Aussagen wie z.B. das
    Sich-Schneiden der drei Höhen eines Dreieckes in einem Punkt, die--
    obwohl an sich keineswegs evident-- doch mit solcher Sicherheit
    bewiesen werden konnten, dass ein Zweifel ausgeschlossen zu sein
    schien.  Diese Klarheit und Sicherheit machte einen
    unbeschreiblichen Eindruck auf mich
    .")

    -- Albert Einstein, Autobiographical Notes, pages 8 and 9 in Albert Einstein: Philosopher-Scientist, ed. by Paul A. Schilpp

    From a website by Hans-Josef Küpper:

    "Today
    it cannot be said with certainty which book is Einstein’s 'holy
    geometry book.'  There are three different titles that come into
    question:

    Theodor Spieker,
    1890

    Lehrbuch der ebenen
    Geometrie. Mit Übungsaufgaben für höhere Lehranstalten.

    Heinrich Borchert
    Lübsen, 1870

    Ausführliches
    Lehrbuch der ebenen und sphärischen Trigonometrie. Zum
    Selbstunterricht. Mit Rücksicht auf die Zwecke
    des praktischen Lebens.

    Adolf Sickenberger,
    1888

    Leitfaden der
    elementaren Mathematik.

    Young
    Albert Einstein owned all of these three books. The book by T.
    Spieker was given to him by Max Talmud (later: Talmey), a Jewish
    medic. The book by H. B. Lübsen was from the library of his uncle
    Jakob Einstein and the one of A. Sickenberger was from his parents."

    Küpper does not state clearly his source for the geometry-book information.

    According to Banesh Hoffman and Helen Dukas in Albert Einstein, Creator and Rebel, the holy geometry book was Lehrbuch der Geometrie zum Gebrauch an höheren Lehranstalten, by Eduard Heis (Catholic astronomer and textbook writer) and Thomas Joseph Eschweiler.

    An argument for Sickenberger from The Young Einstein: The Advent of Relativity (pdf), by Lewis Pyenson, published by Adam Hilger Ltd., 1985:

        "Throughout Einstein's five and a half years at
    the Luitpold Gymnasium, he was taught mathematics from one or
    another edition of the separately published parts of
    Sickenberger's Textbook of Elementary Mathematics
    When it first appeared in 1888 the book constituted a major
    contribution to reform pedagogy.  Sickenberger based his book on
    twenty years of experience that in his view necessarily took
    precedence over 'theoretical doubts and systematic scruples.'  At
    the same time Sickenberger made much use of the recent
    pedagogical literature, especially that published in the pages of
    Immanuel Carl Volkmar Hoffmann’s Zeitschrift für mathematischen und naturwissenschaftlichen Unterricht,
    the leading pedagogical mathematics journal of the day.  Following
    in the tradition of the reform movement, he sought to present
    everything in the simplest, most intuitive way possible.  He
    opposed introducing scientific rigour and higher approaches in an
    elementary text.  He emphasised that he would follow neither the
    synthesis of Euclidean geometry nor the so-called
    analytical-genetic approach.  He opted for a great deal of freedom in
    the form of presentation because he believed that a textbook was
    no more than a crutch for oral instruction.  The spoken word, in
    Sickenberger's view, could infuse life into the dead forms of the
    printed text.  Too often, he insisted in the preface to his text,
    mathematics was seen and valued 'as the pure science of
    reason.'  In reality, he continued, mathematics was also 'an
    essential tool for daily work.'  In view of the practical
    dimension of mathematics Sickenberger sought most of all to
    present basic propositions clearly rather than to arrive at
    formal conciseness.   Numerous examples took the place of long,
    complicated, and boring generalities.  In addition to the
    usual rules of arithmetic Sickenberger introduced diophantine
    equations.  To solve three linear, homogeneous, first-order
    equations with three unknowns he specified determinants and
    determinant algebra.  Then he went on to quadratic equations and
    logarithms.  In the second part of his book, Sickenberger treated
    plane geometry.
         According to a biography of Einstein written
    by his step-son-in-law, Rudolf Kayser-- one that the theoretical
    physicist described as 'duly accurate'-- when he was twelve years
    old Einstein fell into possession of the 'small geometry book'
    used in the Luitpold Gymnasium before this subject was formally
    presented to him.  Einstein corroborated Kayser's passage in
    autobiographical notes of 1949, when he described how at the age
    of twelve 'a little book dealing with Euclidean plane geometry'
    came into his hands 'at the beginning of a school year.'  The
    'lucidity and certainty' of plane geometry according to this
    'holy geometry booklet' made, Einstein wrote, 'an indescribable
    impression on me.'  Einstein saw here what he found in other
    texts that he enjoyed: it was 'not too particular' in logical
    rigour but 'made up for this by permitting the main thoughts to
    stand out clearly and synoptically.'  Upon working his way through
    this text, Einstein was then presented with one of the many
    editions of Theodor Spieker's geometry by Max Talmey, a medical
    student at the University of Munich who dined with the Einsteins
    and who was young Einstein’s friend when Einstein was between the
    ages of ten and fifteen.  We can only infer from Einstein's
    retrospective judgment that the first geometry book exerted an
    impact greater than that produced by Spieker's treatment, by the
    popular science expositions of Aaron Bernstein and Ludwig Büchner
    also given to him by Talmey, or by the texts of Heinrich Borchert
    Lübsen from which Einstein had by the age of fourteen taught himself differential and integral calculus.
         Which text constituted the 'holy geometry
    booklet'?  In his will Einstein gave 'all his books' to his
    long-time secretary Helen Dukas.  Present in this collection are
    three bearing the signature 'J Einstein': a logarithmic and
    trigonometric handbook, a textbook on analysis, and an
    introduction to infinitesimal calculus.  The signature is that of
    Einstein's father's brother Jakob, a business partner and member
    of Einstein's household in Ulm and Munich.  He presented the books
    to his nephew Albert.  A fourth book in Miss Dukas's collection,
    which does not bear Jakob Einstein's name, is the second part of
    a textbook on geometry, a work of astronomer Eduard Heis's which
    was rewritten after his death by the Cologne schoolteacher Thomas
    Joseph Eschweiler.  Without offering reasons for his choice
    Banesh Hoffmann has recently identified Heis and Eschweiler's
    text as the geometry book that made such an impression on
    Einstein.  Yet, assuming that Kayser's unambiguous reporting
    is correct, it is far more likely that the geometrical part of
    Sickenberger's text was what Einstein referred to in his
    autobiographical notes.  Sickenberger's exposition was published
    seven years after that of Heis and Eschweiler, and unlike the
    latter it appeared with a Munich press.  Because it was used in
    the Luitpold Gymnasium, copies would have been readily available
    to Uncle Jakob or to whoever first acquainted Einstein with
    Euclidean geometry."

    What might be the modern version of a "holy geometry book"?

    I suggest the following,
    first published in 1940:

    The image “http://www.log24.com/log/pix05B/BasicGeometry.gif” cannot be displayed, because it contains errors.

    Click on picture for details.

  • Rehearsing Hell

    Art critic Michael Kimmelman
    in today's New York Times:

    The Los Angeles veteran Mike Kelley's latest show is a sprawling,
    scabrous spectacle of noisome installations and hilarious videos,
    occupying the whole of the cavernous Gagosian Gallery in Chelsea.
    Ingratiating Mr. Kelley's work never has been, nor is it now. But
    serious it is, in its brainy, abrasive, black-humored way, and this is
    by far his most ambitious and perversely entertaining effort, an
    attempted Gesamtkunst-werk of satanic rituals and advertising jingles
    mingled with allusions to Godard, German Expressionist cinema and
    Stockhausen....
        A teenage girl dressed like a hillbilly recounts
    a nonsense parable in the manner of H. P. Lovecraft crossed with William Faulkner
    as part of a faux-reality show....
       
    Did I mention the church confirmation in
    which a plump female communicant morphs into a devil worshiper, and
    teenage boys dressed in Nazi outfits suddenly rap about sex with fat
    women?....
         ... Mr. Kelley's deep roots are in the performance tradition going back to the Vienna Actionists.

    For descriptions of the Vienna Actionists, do a Google search.

    From yesterday:

    Angels
      Even devils too
      Wait to show
    How far we come
    To joy
    -- Chris Whitley, "To Joy    
    (Revolution of the Innocents)" --
    mp3 and lyrics.

    It seems that Mike Kelley and Michael Kimmelman are among Chris
    Whitley's "devils."  Let us hope that they enjoy the company of
    General Augusto Pinochet (see previous entry) in the afterlife.

    Related material: Art Wars and The Crimson Passion.

  • Buckley and Pinochet

    Yesterday, William F. Buckley, Jr., author of God and Man at Yale, turned 80.

    Here is an entry from yesterday, postponed until today so it would not
    intervene between yesterday's related entries "Crossroads" and "For
    Constantine's Angel."

    Recommended reading

    for William F. Buckley, Jr.


    1. Joyce and Aquinas
      (Yale Studies in English)
    2. God and Man in Twentieth-Century Fiction
    3. Modern Literature and the Sense of Time
    4. Three Young Men in Rebellion
    5. James Joyce: Unfacts, Fiction, and Facts
    6. Yeats and the Human Body
    7. Poetry and Prayer

    These titles are from an Amazon.com
    search.  All seem to be by the same "William T. Noon," a Jesuit
    priest.  Except for Joyce and Aquinas and Poetry and Prayer
    little of Noon's work is now remembered.

    Thought to accompany the above reading list:

    "And now I was beginning to surmise:
    Here was the library of Paradise."

    -- Hermann Hesse, Magister Ludi

    Before he attains to Paradise, Buckley's reading list in Purgatory might include the complete weblog of Andrew Cusack, a young Christian Fascist at the University of St. Andrews.

    A related item...

    According to "Today in History," by the Associated Press, for Nov. 25, 2005,

    "Today's Birthdays: Former Chilean dictator General Augusto Pinochet is 90...."

    If, in fact, Hell also has a library, let us pray that it contains, for Pinochet's future edification, the collected works of Pablo Neruda.

  • Crossroads

    In memory of Diego Rivera,

    who died on this date in 1957

    "... the socialist muralist Diego
    Rivera, hired by Nelson Rockefeller to paint a fresco for the newly
    constructed Rockefeller Center in New York, inserted a likeness of
    Lenin's head into the fresco. Rockefeller insisted that the head be
    replaced or removed, and when Rivera refused the fresco was destroyed....
    The event... is captured with
    great wit in E.B. White's poem...."

    -- Harvard Law Review


    I Paint What I See
    [A Ballad of Artistic Integrity]
    by E.B. White
    The New Yorker, 20 May 1933

    "'What do you paint, when you paint on a wall?'

    Said John D.'s grandson Nelson.

    'Do you paint just anything there at all?

    'Will there be any doves, or a tree in fall?

    'Or a hunting scene, like an English hall?'

    'I paint what I see,' said Rivera.

    'What are the colors you use when you paint?'

    Said John D.'s grandson Nelson.

    'Do you use any red in the beard of a saint?

    'If you do, is it terribly red, or faint?

    'Do you use any blue? Is it Prussian?'

    'I paint what I paint,' said Rivera.

    'Whose is that head that I see on the wall?'

    Said John D.'s grandson Nelson.

    'Is it anyone's head whom we know, at all?

    'A Rensselaer, or a Saltonstall?

    'Is it Franklin D.? Is it Mordaunt Hall?

    Or is it the head of a Russian?

    'I paint what I think,' said Rivera.

    'I paint what I paint, I paint what I see,
    'I paint what I think,' said Rivera,
    'And the thing that is dearest in life to me
    'In a bourgeois hall is Integrity;
    'However . . .
    'I'll take out a couple of people drinkin'
    'And put in a picture of Abraham Lincoln;
    'I could even give you McCormick's reaper
    'And still not make my art much cheaper.
    'But the head of Lenin has got to stay
    'Or my friends will give the bird today,
    'The bird, the bird, forever.'

    'It's not good taste in a man like me,'

    Said John D.'s grandson Nelson,

    'To question an artist's integrity

    'Or mention a practical thing like a fee,

    'But I know what I like to a large degree,

    'Though art I hate to hamper;

    'For twenty-one thousand conservative bucks

    'You painted a radical. I say shucks,

    'I never could rent the offices-----

    'The capitalistic offices.

    'For this, as you know, is a public hall

    'And people want doves, or a tree in fall

    'And though your art I dislike to hamper,

    'I owe a little to God and Gramper,

    'And after all,

    'It's my wall . . .'

    'We'll see if it is,' said Rivera.


    Related material:

    Pictures of the Rockefeller Center mural,
    "Man at the Crossroads," and
    Rivera's re-creation of the mural,
    "Man, Controller of the Universe."

    See also another treatment of the "Man at the Crossroads" theme--

    The Concrete Gospel
    of Donald E. Knuth:

    In Hoc Signo
    (from Feb. 18),
    continued --

    The image “http://www.log24.com/log/pix05/050219-Signo.gif” cannot be displayed, because it contains errors.

    This holy icon
    appeared at
    N37°25.638'
    W122°09.574'
    on August 22, 2003,
    at the Stanford campus.

    -- Log24, Feb. 19, 2005  
     

  • For Constantine's Angel

    The image “http://www.log24.com/log/pix05B/051124-Whitley2.jpg” cannot be displayed, because it contains errors.

    Lyrics by Chris Whitley,
    who died on Sunday,
    November 20, 2005:

    Angels
      Even devils too
      Wait to show
    How far we come
    To joy

    -- "To Joy    
    (Revolution of the Innocents)" --
    mp3 and lyrics.