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25 years of AGM

Submitted by Richard Zach on Tue, 03/15/2011 - 3:46pm

The AGM Theory of Belief Revision was 25 years old last year, and the JPL has a special anniversary issue on it.

Hilary Putnam Awarded 2011 Schock Prize in Logic and Philosophy

Submitted by Richard Zach on Mon, 03/14/2011 - 10:47am

The Swedish Academy awarded the 2011 Rolf Schock Prize to Hilary Putnam "for his contribution to the understanding of semantics for theoretical and ‘natural kind’ terms, and of the implications of this semantics for philosophy, theory of knowledge, philosophy of science and metaphysics".

Here's the citation:

Hilary Putnam is one of the most versatile philosophers of our time. He has written more than 20 books and more than 300 articles, on subjects ranging from mathematical logic to religion.

The work that is being rewarded with the 2011 Rolf Schock Prize in Logic and Philosophy belongs to the interface between philosophy of language, philosophy of science and metaphysics. In particular, it concerns the semantics for two sorts of linguistic expressions: theoretical terms in science, like ‘atom’ and ‘energy’, and everyday words for ‘natural kinds’, like ‘gold’ and ‘water’.

The starting point is Willard Van Orman Quine’s critique of the distinction between analytic and synthetic propositions. The former are said to be true by virtue of their meaning, while the truth of the latter also depends on the world. Thus, ‘all bachelors ride bicycles’ is synthetic, while ‘all bachelors are unmarried’ is analytic.

Unlike Quine, Putnam held fast to this example of analyticity: anyone who denies the proposition must be using one of the words to mean something other than we do. But for theoretical terms, no clear-cut distinction is possible. These terms are associated with clusters of natural laws. If we reject all statements of laws concerning energy, we have undoubtedly changed the meaning of the term ‘energy’; but for a change to take place it is unclear which, or how many, statements we must reject.

Accordingly, the meaning of theoretical terms can be preserved when a theory is modified. This revision of semantics makes, in turn, scientific realism possible: the new theory deals with the same phenomena as the old one.

Putnam subsequently combined these views with meaning externalism. The meaning of ‘natural kind’ terms, such as ‘water’, is determined by language users’ surroundings and not by the stereotypical characteristics they associate with the term, such as quenching thirst and flowing in rivers. On another planet outwardly just like ours, and perceived as such by its inhabitants, a substance other than H2O – XYZ, say – could have these characteristics instead. For speakers on this Twin Earth, ‘water’ would mean ‘XYZ’, while we should truthfully deny that there is any water on their planet. The conclusion is that ‘meanings just ain’t in the head’.

Hilary Whitehall Putnam was born in Chicago in 1926. After studies at the University of Pennsylvania and Harvard University, he received his PhD in 1951 from the University of California, Los Angeles, with Hans Reichenbach and Rudolf Carnap as his supervisors. In 1965, after a long residence at the Massachusetts Institute of Technology (MIT), he moved to Harvard where, in 1976, he was appointed as Walter Beverly Pearson Professor of Mathematical Logic. Today, he is Cogan University Professor Emeritus at Harvard University.

Putnam is a past President of the American Philosophical Association (Eastern Division), the Philosophy of Science Association and the Association for Symbolic Logic. He is a Fellow of the American Academy of Arts and Sciences, and a Corresponding Fellow of the British Academy (the UK’s national academy for the humanities and social sciences) and the French Académie de Sciences Morales et Politiques. He is married to Ruth Anna Putnam.

The prize for visual arts goes to Marlene Dumas. The prizes for Music and Mathematics will be annoucned on March 21.

PhD Fellowships in Mathematical Philosophy in Munich

Submitted by Richard Zach on Thu, 03/10/2011 - 9:21am

From Hannes Leitgeb's new Center for Mathematical Philosophy at the LMU Munich:

Four doctoral fellowships are being advertised at the Munich Center for
Mathematical Philosophy (MCMP). The MCMP, which is devoted to
applications of logical and mathematical methods in philosophy, has
recently been established at the Ludwig-Maximilians-University Munich
(LMU) based on generous support by the Alexander von Humboldt
Foundation. Directed by Professor Hannes Leitgeb, the Center hosts a
vibrant research community of university faculty, postdoctoral fellows,
doctoral fellows, and visiting fellows.

Details here .

LogBlog Move

Submitted by Richard Zach on Wed, 03/09/2011 - 10:10pm

LogBlog moved last year. I've tried to make it noticeable as little as possible--the RSS feed has been redirected for a while. So even if your feed reader is set to you stil get the new posts.  But you should really change it!  (to

And now I've also put in redirects from all the old pages, so no more finding an old LogBlog post and landing on a version where you can't comment.  If you do find one, please let me know!

Venn Diagrams

Submitted by Richard Zach on Sat, 03/05/2011 - 1:59pm

Funny Venn diagrams, a vaguely-logic-related internet thing:

Not sure where that last one originated.  Any other good suggestions?

Representation of Women in Philosophy, Again

Submitted by Richard Zach on Wed, 02/16/2011 - 11:50am

Since Leiter just quoted data on women in philosophy faculty positions collected by Kathryn Norlock, and over at Feminist Philosophers someone asked for a breakdown by tenure status, here it is. This is survey data from 2003 (the same dataset from which the figures Leiter quotes come) which means there is sampling error. The first (grey) line gives the percentages for each category of the total, the second line gives the percentage of women per category (i.e., 6.3% of all surveyed philosophy faculty are tenured women; of the tenured philosophy faculty surveyed, 17.1% are women). You can make your own tables here.  See also previous discussion and comparison with other fields and data on the pipeline here and here

The problem is that the standard errors in the survey results are really high. We talked about this in the previous post, noting that this data isn't very reliable.  The data was compiled from a survey of approx 18,000 faculty, of which 1.9% were philosophers. So it's based on a sample of about 350 out of a total of approx. 23,000 philosophy faculty (full and part time) overall in 2003. In the case of these figures in particular, what the survey tells us is only that the percentage of women among tenured philosophy faculty is somewhere between 8.5% and 25.6% (at 95% confidence). (Edited, thanks to Jingjing Wu for help with the stats.)

Tenure status and gender Tenured, male
Tenured, female
On tenure track, male
On tenure track, female
Not on tenure track, male
Not on tenure track, female
Total 19.3 8.7 7.1 5.1 31.1 28.7 100%
  per category   31.0    41.8    47.9  42.5
Philosophy 30.5 6.3 10.5 1.5 39.0 12.3 100%
  per category   17.1    12.5    23.9  21.0
Standard Errors
Total 0.30 0.19 0.20 0.15 0.30 0.22  
Philosophy 3.15 1.80 2.04 0.67 4.78 2.73  
Weighted Sample Sizes (n/1,000s)
Total 1211.85            
Philosophy 13.19            
NOTE: Rows may not add up to 100% due to rounding.
SOURCE: U.S. Department of Education, National Center for Education Statistics, 2004 National Study of Postsecondary Faculty (NSOPF:04).
Computation by NCES QuickStats on 2/16/2011

NB: I've switched blogging software. If you click a link and land on a page and wonder why you can't comment, take the url, e.g., and replace 'people' by 'www' and 'logblog' by 'blog' to get to the current version like so:

Visual Representation of Philosophers' Significance and Influence

Submitted by Richard Zach on Wed, 02/09/2011 - 8:22pm

My colleagues Marian Dörk and Sheelagh Carpendale over in the Computer Science department have taken data on philosophers from Freebase as a test case for their EdgeMaps visualization project.

Freebase provides data about interests, professions, birthdates, influence connections, and other relations from Wikipedia. For the purpose of this paper, we have constrained the dataset to philosophers that influenced at least one other philosopher, resulting in 42 philosophers. For each philosopher we store the name, birthdate, description, an image, interests, and professions. Furthermore, we store the directed influence links between philosophers.

Go to the EdgeMaps page, click on the "open demo" button, and explore. The button in the top left switches between a timeline view and an influence "yarnball".Of course, the map is only as good as the data that went in--see the example of Frege below which is missing a big fat influence arrow coming from Kant!--but still, very cool!

EdgeMap of Frege

SEP Entry on the Liar Paradox

Submitted by Richard Zach on Fri, 02/04/2011 - 1:22pm

Logic in the Undergraduate Mathematics Curriculum

Submitted by Richard Zach on Fri, 02/04/2011 - 11:39am

As part of the work of the Committee on Logic Education of the Association of Symbolic Logic, Marcia Groszek and Tamara Lakins organized a special session on logic in the undergraduate mathematics curriculum at the Joint Mathematics Meeting last month in New Orleans.  The session was very successful: excellent talks, good turnout.  The talks were:

  • Breadth, Depth, Disputes, Drama, and Campus Pranks:  The Possibilities and Pleasures of Co-teaching Logic, by James M. Henle
  • A Course Emphasizing Mathematical Logic and Reasoning that is Appropriate for General Education and Elementary Education Majors, by Warren W. Esty
  • Seemingly Abstruse Logical Principles Have Practical Importance, by Susanna S. Epp
  • Applied Logic Courses in the Mathematics Curriculum, by Lawrence S. Moss
  • Technology in Logic Education:  Courseware, Automated Assessment and Data Minin, by Dave Barker-Plummer

You can find abstracts and links to the presentation materials on the ASL CLE's page on the special session.

Begging the Question

Submitted by Richard Zach on Wed, 02/02/2011 - 1:13pm

Just happened upon this LanguageLog post on "begging the question" from last year.  Very interesting!

Gregory Hjorth, 1963-2011

Submitted by Richard Zach on Fri, 01/28/2011 - 12:55pm

Greg Hjorth died unexpectedly on January 13. He was 47.  Greg received his degree from UC Berkeley under the supervision of Hugh Wooding in 1993.  He held positions at Caltech, UCLA, and the University of Melbourne.  Together with Alexander Kechris, he recieved the ASL's Karp Prize in 2003. Last year, he was chosen as Tarski Lecturer at Berekely.  He was also an outstanding chess player, and awarded the title International Master in 1984.

There is a memorial group on facebook, and one at the Australian.  Greg and Herb Enderton will be honored at the upcoming Very Informal Gathering of logicians at UCLA, February 4. Some pictures and tributes are collected here.

Here's the abituary from the front page of the UCLA Math Department:

Professor Greg Hjorth died of a heart attack in his birth city of Melbourne, Australia, on Jan. 13. He was 47. Hjorth was recognized as a young chess whiz in his primary school years. He quickly advanced to tournament chess, becoming joint Commonwealth Champion in 1983 and earning his International Master title in 1984. He played Garry Kasparov, among other accomplished chess rivals, but took his own later advice that "if you're not in the top 100 by 21, get out." Hjorth's passion for chess played over to mathematical logic, a field that saw him reach great heights with high academic honors and wide recognition. After receiving his undergraduate degree in mathematics and philosophy at the University of Melbourne, Hjorth continued his studies at UC Berkeley, where he received his PhD in mathematics under the supervision of Hugh Woodin in 1993. As a graduate student, Hjorth was recognized for his exceptional talent, and his brilliant thesis was awarded the first Sacks Prize in 1994 by the Association for Symbolic Logic for his research in descriptive set theory and its surprising consequences concerning the relationship between projective sets and large cardinals. Hjorth pursued his postdoctoral studies at Caltech for two years then joined the mathematics faculty at UCLA in 1995, where he was made full professor in 2001. Since 2006, he spent two quarters of each year at the University of Melbourne appointed to a prestigious Australian Research Council professorial fellowship.

Over his 16 years at UCLA, Hjorth has been acknowledged as a world leader in the field of mathematical logic and its applications to other fields of mathematics. He has made a series of stunning and far reaching contributions, in particular to ergodic theory and orbit equivalence of group actions. These included the development of entirely new theories, including what is now called Hjorth's theory of turbulence, which has had a major impact in contemporary work in set theory and its applications. Hjorth was known as a brilliant problem solver, having been able to achieve major breakthroughs in problems that were previously considered in tractable, including his remarkable work on the famous topological Vaught Conjec ture and most recently, his results on the incomparability of treeable equivalence relations. His work consistently amazed his colleagues with its uncanny originality and technical wizardry and has been recognized by many honors, including a Sloan Foundation Fellowship in 1997, an invited lecture at the International Congress of Mathematicians in 1998, the ASL Karp Prize in 2003 (joint with Alexander Kechris), and last year, an invitation to deliver one of the major lecture series in logic, the Alfred Tarski Lectures at UC Berkeley. Hjorth supervised eight PhD students at UCLA, including 2008 UCLA Math PhD Inessa Epstein, who also received the prestigious Sacks prize.

Hjorth will be richly remembered by fellow colleagues as a brilliant mathematician in constant pursuit of solutions to intractable problems, and as a committed and caring teacher. He is survived by his parents Noela and Robert, and his sister Larissa. In honor of Hjorth, the UCLA Logic Center is hosting a special lecture by Alexander Kechris on Hjorth’s work to be held Friday, February 4 at 2:30pm in Young Hall, CS24. The in memoriam will begin at 2:00pm.

Proof by Extortion

Submitted by Richard Zach on Thu, 01/27/2011 - 11:01pm

Along the lines of philosophers' "proofs that p" and methods of mathematical proof, Saturday Morning Breakfast Cereal brings you even better methods of proof:

History of Modal Logic

Submitted by Richard Zach on Mon, 11/29/2010 - 12:54pm

Roberta Ballarin's excellent article on the history of modal logic is now online at the SEP.

A Biochemist Weighs in on the Closing of Humanities Departments at SUNY Albany

Submitted by Richard Zach on Sat, 11/27/2010 - 5:05pm

Gregory A. Petsko is the Gyula and Katica Tauber Professor of Biochemistry & Chemistry at Brandeis University. In his column in Genome Biology (also published at Inside Higher Ed), he wrote an open letter to George Philip, the President of SUNY Albany, who evicerated the language department at his university.  Priceless:

It seems to me that the way you went about [announcing the closure of the departments in a Friday afternoon meeting] couldn't have been more likely to alienate just about everybody on campus. In your position, I would have done everything possible to avoid that. I wouldn't want to end up in the 9th Bolgia (ditch of stone) of the 8th Circle of the Inferno, where the great 14th century Italian poet Dante Alighieri put the sowers of discord. There, as they struggle in that pit for all eternity, a demon continually hacks their limbs apart, just as in life they divided others.

The Inferno is the first book of Dante's Divine Comedy, one of the great works of the human imagination. There's so much to learn from it about human weakness and folly. The faculty in your Italian department would be delighted to introduce you to its many wonders -- if only you had an Italian department, which now, of course, you don't.

Happy 100th, Freddy Ayer

Submitted by Richard Zach on Fri, 10/29/2010 - 7:36pm

A. J. Ayer was born 100 years ago today.

Herbert B. Enderton, 1936-2010

Submitted by Richard Zach on Thu, 10/28/2010 - 10:37am

Sad news:

With sadness we report the death on October 20 of Herbert Bruce Enderton, who had been battling leukemia for several months. He was Professor Emeritus of Mathematics at UCLA and a former member of the faculties of Mathematics and of Logic and the Methodology of Science at Berkeley. Widely known for his textbooks in the areas of logic, Enderton as a contributor to recursion theory, the theory of definability, models of nalysis, computational complexity, and history of logic.

The Enderton family requests that flowers not be sent. There will be no funeral, but a memorial service will be held at a future date.

CfP: Tools for Teaching Logic 2011

Submitted by Richard Zach on Tue, 10/26/2010 - 4:27pm

If you're interested or involved in teaching logic, please consider subitting something to this conference. And if you don't have anything to submit, keep it in mind for your summer travel plans next year. Spain in June!

Third International Congress on Tools for Teaching Logic
June 1-4 2011, Salamanca, Spain

The congress will focus on a variety of topics including: logic teaching software, teaching formal methods, logic in the humanities, dissemination of logic courseware and logic textbooks, methods for teaching logic at different levels of instruction (secondary education, university level, and postgraduate), presentation of postgraduate programs in logic, e-learning, logic games, teaching argumentation theory and informal logic, pedagogy of logic.

Call for papers

  • Submission of Papers: December 8th, 2010
  • Notification of Acceptance: February 1st, 2011
  • Final Camera-Ready Submission Due: March 1st, 2011

We are inviting submissions on the conference topics, or on any other aspect of teaching logic or logic teaching software. We prefer 6 or 8 page submissions. Submissions must not exceed 8 pages. It is expected that each accepted paper be presented at the conference by one of its authors. Papers must be submitted electronically, in pdf-format, at the TICTTL EasyChair website . Submissions need not be formatted in LNCS style! However, accepted full papers must be formatted in LNCS style, and must respect the page limit.

Patrick Blackburn, Hans van Ditmarsch, Maria Manzano, Fernando Soler

Commenting Works Again!

Submitted by Richard Zach on Sat, 10/23/2010 - 10:24am

Commenting works again.... There were a lot (and by a lot, I mean thousands!) of spam comments over the summer, which led me to first turn off commenting, and then install a spam filter, which worked so well that it would not accept any comments at all. If fallen back to a simple Captcha. Hope that keeps the spammers out, and hope it makes the commenters come back!  So if you had anything to say in response to a post over the last few months... now you can. 

 Also, if you haven't changed the URL of the RSS feed. Please do:

Bleg: Philosophy of Language Anthologies

Submitted by Richard Zach on Tue, 10/12/2010 - 11:27am

I'm supposed to choose a text for my philosophy of language course next term. So far I've always used Martinich, but I'm getting bored with it.  Also, of the available options, it seems to be the most expensive one.  I've looked at Ludlow's collection, but that's maybe a bit too heavy (both literally and figuratively).  Also, he misspells Carnap's name.  I'm gravitating towards Byrne and Kölbel's Arguing about Language right now.  It's missing a few topics/pieces which I would have covered (notably, no speech acts, and no Putnam), but in return it covers a few things that aren't covered in Martinich and/or Ludlow (vagueness, metaphor, fictional discourse).  Also, it's got the highest percentage of female contributors, and the lowest price tag.  Any experiences? Advice?

Kurt Gödel Research Prize Fellowships

Submitted by Richard Zach on Tue, 10/05/2010 - 11:41am

The Kurt Gödel Society is proud to announce the commencement of the second round of the Kurt Gödel Research Prize Fellowships Program. The research fellowship prize program is sponsored by the John Templeton Foundation and will offer:

  • two Ph.D. (pre-doctoral) fellowships of EUR 100,000
  • two post-doctoral fellowships of EUR 100,000 and
  • one unrestricted fellowship of EUR 100,000

One International Board of Jurors will be in charge of evaluating the applications and determining up to twenty finalists whose papers will be published in a special issue of the Annals of Pure and Applied Logic, and another international Board of Jurors will be in charge of determining the winners. Both Boards will be chaired by Prof. Harvey Friedman, Ohio State University (USA).

Board of Jurors for Determining the Finalists

  • Jeremy AVIGAD, Carnegie Mellon University, (USA)
  • Lenore BLUM, Carnegie Mellon University, (USA)
  • Harvey FRIEDMAN, Ohio State University (USA) CHAIR
  • John HARRISON, Intel Corporation, (USA)
  • Kenneth KUNEN, University of Wisconsin, (USA)
  • Angus MACINTYRE, Queen Mary, University of London and Royal Society, (UK)
  • Hiroakira ONO, JAIST Research Center for Integrated Science, (JAPAN)
  • Pavel PUDLAK, Czech Academy of Sciences, (Czech Republic)
  • Michael RATHJEN, University of Leeds, (UK)
  • Frank STEPHAN, National University of Singapore, (SINGAPORE)
  • William TAIT, University of Chicago, (USA)
  • Simon THOMAS, Rutgers University, (USA)
  • Albert VISSER, University of Utrecht (NL)
  • Andreas WEIERMANN, Ghent University, (BELGIUM)
  • Boris ZILBER, University of Oxford, (UK)

Board of Jurors for Determining the Winners

  • Lev BEKLEMISHEV, Russian Academy of Sciences (RUS)
  • Harvey FRIEDMAN, Ohio State University (USA) CHAIR
  • Dov M. GABBAY, King's College London (UK)
  • Warren D. GOLDFARB, Harvard University (USA)
  • Howard Jerome KEISLER, University of Wisconsin (USA)

Goal and Criteria of Merit

The purpose of these fellowships is to support original research in, and areas surrounding, the foundations of mathematics. (See Scope below for more details.) These fellowships are intended to carry forward the legacy of Kurt Gödel, whose works exemplify deep insights and breakthrough discoveries in mathematical logic, with profound impact on the philosophy and foundations of mathematics. In pursuit of similar insights and discoveries, we adopt the following criteria of merit for evaluating Fellowship applications:

  1. Intellectual merit, scientific rigor and originality of the submitted
    paper and work plan. The paper and research plans should combine visionary
    thinking with academic and scientific excellence.
  2. Potential for significant contribution to basic fundamental issues of
    wide interest, and the likelihood for opening new, seminal lines of inquiry
    that bear on such issues.
  3. Impact of the Fellowship on the project and likelihood that the
    Fellowship will make the proposed new lines of research possible.
  4. The expectation that the proposed research will be successful.
  5. Qualifications of the applicants will be evaluated on the basis of all
    available information including CV, research paper, research plans, research
    accomplishments, and letters of recommendation (recommendation letters are not
    required for senior applications).

Winners' Model Projects:

Model Question


Original fellowship proposals in the areas of

  • set theory
  • recursion theory
  • proof theory/intuitionism
  • model theory
  • computer assisted reasoning
  • philosophy of mathematics

All fellowship proposals, regardless of subject area, will be judged according

  • the relevance and resemblance of the research (finished and proposed) to the great insights and originality of Kurt Gödel
  • its general interest and clarity of motivation
  • its rigorous scientific quality and depth.

Submission Instructions

The three categories of fellowships are specified as follows:

  • Ph.D.(pre-doctoral): being in the stage before finishing the thesis (or equivalent achievements)
  • Post-doctoral: being in the stage within 10 years after finishing the thesis (or equivalent achievements)
  • Unrestricted: also open to senior applicants

The submission must consist of:

  • one document A in PDF format containing
    • the CV
    • the project description
    • the recommendation letters
  • one document B in PDF format containing the article
  • one text abstract relating to B

Maximum allowed length of the abstract is 500 words. Document A containing the CV, the project description, and the recommendation letters must be prepared in the following way:

  • minimum font size: 10pt
  • paper size: A4
  • maximum length of the CV: 3 pages

The CV must contain the list of all/most important publications. The CV must clearly state to which  category the application belongs.

  • maximum length of project description: 4 pages. Project description should clearly state where and at which institution the
    applicant intends to carry out the project.
  • minimum 2 (two)/maximum 3 (three) 1-page recommendation letters, in case of applications belonging to the categories Ph.D.(pre-doctoral) and post-doctoral fellowships. (The recommendation letters should be scanned and included into the PDF document)

The submission must be in English.

The Board and the Program Chair reserve the right:

  • to consider only submissions with reasonable format
  • to reassign a submission to another category as applied for.

The applicant will be informed about the reasons for such a decision.

Submission Page

The EasyChair system is used for managing the submissions. For submitting a proposal please go to


  • November 15, 2010. Submissions deadline
  • February 28, 2011. Jury decision on the papers for publication (at most 20)
  • March 1, 2011. Final versions due
  • March 6, 2011. Jury decision on winners due
  • April 28-30, 2011. Conference and the Award Ceremony
  • June-October, 2011. Commencement of the Fellowships

E-mail contact: