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January 26, 2007
Errata
Well, the first 2 weeks of teaching from Fitting and Mendelsohn's First-Order Modal Logic
A couple of minor thoughts on it: it seems to me that after the introduction of semantics for K,T, D, K4, B, S4 and S5 in the first half of the first chapter, the discussion of tense logic from pages 24-27 represents a missed oportunity to draw out the parallels. The section discusses four different ways to understand tensed sentences, two of which involve treating tensed sentences as equivalent to first order classical formulas in which one simply quantifies over time instants, and the suggestion that we use operators like 'G' ( it will always be the case that) and 'F' (it will be the case that) like '[]' (box) and '<>' (diamond) is discussed in less than half a page and left at the intuitive level, e.g.:
For example, the thesis []P->P, fails. Just because it will always be true that P, it does not follow that P is true now. (p. 27)
But this isn't justified with reference to any particular model theory - we're just supposed to get it from our intuitive understanding of 'it will always be the case that.' This would have been understandable if the writer couldn't assume that his reader would be able to follow a discussion involving putting the semantics for those operators into a definition of truth in a model, and considering what formulas involving them come out valid for different classes of frames, but the book has just done exactly that for ordinary modal logic, and considered what formulas come out valid if we assume that the accessibility relation is e.g. transitive and reflextive, or serial and so it would have been a great place to at least mention that you can get different tense logics by putting different restrictions on the "earlier than" relation (partial ordering, total ordering, total ordering with no maximum or minimum, density ... etc). Given this I've been supplementing our discussion of tense logic with John P. Burgess' "Basic Tense Logic" from volume II of the Handbook of Philosophical Logic
A second (even more) minor point: like any logic textbook, there are some typos. Here's one:
p. 26 - the interpretations of
- G John wins the election
- H John wins the election
are given as
and
respectively. But, first of all, 'John wins the election' is an infelicitous atomic sentence to use, (what do we make of: at every time in the future, John wins the election ?) 'John is happy' would have been much less confusing. (There's nothing funny about: at every time in the future, John is happy.)
And secondly, those conjunctions should surely be conditionals, otherwise 'G John is happy', means every time is later than the present time and John is happy at it and 'H John is happy' means every time is earlier than the present and John is happy at it!
This, of course, is small stuff, and so far I would recommend the book to anyone who needs to teach modal logic to philosophers who are not logicians. Also Fitting has his own site of errata for the book here.
Posted by logican at 12:24 PM | Comments (0) | TrackBack
January 10, 2007
The Politics of ASL
Is it better to think of the deaf positively as those who speak America Sign Language, rather than negatively as those who have a distinctive kind of impairment? Sounds good perhaps but here's Lennard Davis on the reasons not to:
The central problem with defining deaf people as a linguistic group is that to do so, you have to patrol the fire wall between the deaf and nondeaf in very rigid ways. If deaf people are defined as only those who are native users of ASL, you have to define all nonusers of ASL as "other." That excludes, or at least marginalizes, deaf people who are orally trained -- that is, who were taught to eschew ASL for speech alone; have cochlear implants; or never had the chance to learn sign language. Many people who grew up in non-ASL settings in the 1950s and 1960s and who have quite happily thought of themselves as deaf would have to reassign themselves to some other camp. Likewise, the strict linguistic-group definition expels hard-of-hearing people who have not learned ASL. Ironically, the model also stigmatizes those who have been educated orally; they are seen as victims of oral education rather than as victims of audism. Since it is hearing parents who usually make the decision to educate their deaf children orally, rather than with ASL, or to give them cochlear implants, it doesn't seem fair to define those children as not deaf. The other flaw in the model is that it defines hearing, signing children of deaf adults (CODA's) as deaf, since they are native sign-language speakers. One could argue that CODA's aren't discriminated against by the hearing world, but if one takes that tack, then one has to abandon the idea that language is the key defining term.
To which we can add the following against the specific suggestion considered: it would be crazy to think of the deaf as the community of native speakers of ASL because lots of the deaf speak OTHER sign languages instead.
Posted by logican at 07:56 PM | Comments (0) | TrackBack
January 09, 2007
TARK XI
Call for Papers
Eleventh Conference on Theoretical Aspects of Rationality and Knowledge
(TARK
XI)
June 25-27, 2007
Brussels, Belgium
http://www.tark.be
Sponsors
University of Namur, CORE - University of Louvain, CEREC - Facultés
Universitaires Saint-Louis, and National Fund for Scientific Research
(FNRS)
About the Conference
The mission of the TARK conferences is to bring together researchers
from a wide variety of fields, including Artificial Intelligence,
Cryptography, Distributed Computing, Economics and Game Theory,
Linguistics, Philosophy, and Psychology, in order to further our
understanding of interdisciplinary issues involving reasoning about
rationality and knowledge. Topics of interest include, but are not
limited to, semantic models for knowledge, belief, and uncertainty,
bounded rationality and resource-bounded reasoning, commonsense
epistemic reasoning, epistemic logic, knowledge and action, applications
of reasoning about knowledge and other mental states, belief revision,
and foundations of multi-agent systems.
Submissions are now invited to TARK XI. Strong preference will be given
to papers whose topic is of interest to an interdisciplinary audience,
and papers should be accessible to such an audience. Papers
should 1) contain enough information to enable the program
committee to identify the main contribution of the work; 2) explain the
significance of the work -- its novelty and its practical or theoretical
implications; and 3) include comparisons with and references to relevant
literature. For submission, click on the Submission tab at
http://www.tark.be.
Abstracts should be no longer than ten double-spaced pages (4,000
words). Optional technical details such as proofs may be included in an
appendix. An email address of the contact author should be included.
Papers arriving late or departing significantly from these guidelines
risk immediate rejection. One author of each accepted paper will be
expected to present the paper at the conference.
Economists should be aware that special arrangements have been made with
certain economics journals (in particular, with International Journal of
Game Theory, Games and Economic Behavior, Journal of Economic Theory,
Econometrica, Theory and Decision, and Mathematical Social Sciences) so
that publication of an extended abstract in TARK will not prejudice
publication of a full journal version.
Registration fees
Early registration (before 30th April 2007): 260 EUR (100 EUR for
students).
Late registration (from 1st May 2007): 350 EUR (150 EUR for students).
The Registration fee includes: a reception at the Roy d'Espagne
(http://www.roydespagne.be/index.html), three lunches, a gala dinner at
the
Hotel Metropole (http://www.metropolehotel.com/EN/home.cfm?Lang=EN),
morning and afternoon coffee breaks, one copy of the proceedings.
Accomodations: see http://www.tark.be.
Key Dates
Submission of Abstracts: January 30, 2007 Notification of Authors: March
28, 2007, Camera ready copy of accepted papers: April 30, 2007
Conference: June 25-27, 2007
Program Committee:
Sergei Artemov, CUNY
Vincent Conitzer, Duke University
Lance Fortnow, University of Chicago
Aviad Heifetz, The Open University, Israel
Franz Huber, California Institute of Technology
Adam Kalai, Georgia Institute of Technology
Ron Lavi, Technion
Jerome Lang, Institut de Recherche en Informatique de Toulouse (IRIT)
Martin Meier, Instituto de Analisis Economico
Dov Samet (chair), Tel Aviv University
Burkhard Schipper, University of California, Davis
Robert Stalnaker, MIT
Marc Pauly, Stanford
Muhamet Yildiz, MIT
Program Chair
Dov Samet,
Faculty of Management
Tel Aviv University
Tel Aviv
phone: +972 3 640 6999
email: dovs at tauex.tau.ac.il
Local Organizers
Vincent Vannetelbosch
CORE
University of Louvain
Voie du Roman Pays 34
B-1348 Louvain-la-Neuve
Belgium
Tel: 0032 10 47 41 42
Fax: 0032 10 47 43 01
email: vannetelbosch at core.ucl.ac.be
Pierre-Yves Schobbens
Institut d'Informatique
University of Namur
Rue Grandgagnage, 21
B-5000 Namur
Belgium
Tel: 0032 81 72 49 90
Fax: 0032 81 72 49 67
email: pys at info.fundp.ac.be
Ana Mauleon
CEREC
Facultés Universitaires Saint-Louis
Boulevard du Jardin Botanique 43
B-1000 Brussels
Tel: 0032 2 211 79 35
email: mauleon at fusl.ac.be
Conference Chair
Joseph Y. Halpern
Computer Science Department
Cornell University
Itacha, NY 14853
phone: +1 607 255 9562
fax: +1 607 255 4428
e-mail: halpern at cs.cornell.edu
Posted by logican at 01:32 PM | Comments (0) | TrackBack