A new logic blog, from Ole Hjortland, St. Andrews: Nothing of Consequence.(I collect logic blogs. If you have one and it's not on my blogroll, tell me!)

Gödel would have turned 100 years old today. Happy Birthday, Kurtele! Merry Gödelmas, everyone else! I'm going to report on today's sessions (well, on Hajek's and Putnam's) at the Gödel Centennial conference tomorrow, since I have to get ready now for the fancy Gala Dinner at the Belvedere Palace. ("Black Tie Optional". I guess I'll … Continue reading Happy 100, Kurtele!

Dana Scott just told this joke, which he heard from Ray Smullyan: Two professors at a math conference stand in front of a blackboard, on which is written the sentence "Only an idiot would believe a sentence like this!" The first professor asks the second, "Do you believe that?" The second answers, "Of course not! … Continue reading Logic Joke

I'm in Vienna for the Gödel Centennial conference, Horizons of Truth. Day 1 featured talks by: Angus MacIntyre, How much has mathematics been affected by Gödel's work? His answer: not much (yet). He surveyed the developments arising from Gödel's work (recursion theory, definability theory, results on noncomputability of classical problems such as the undecidability of … Continue reading Gödel Centennial, Day 1

The February issue of Synthese is a special issue on proof-theoretic semantics, edited by Reinhard Kahle and Peter Schröder-Heister. It's papers from a conference in Tübingen in 1999. Dag Prawitz, Meaning Approached Via ProofsPeter Schroeder-Heister, Validity Concepts in Proof-theoretic SemanticsPatrizio Contu, The Justification of the Logical Laws RevisitedLars Hallnäs, On the Proof-theoretic Foundation of General … Continue reading Proof-theoretic Semantics in Synthese

Call for Papers:Uncertainty: Reasoning about probability and vaguenessSeptember 5 to 8, PragueUncertainty is a ubiquitous phenomenon in everyday life, but it is also a topic of fundamental significance to many scientific disciplines. Uncertainty taken here in a broad sense, has many facets - among them probability and vagueness, including possibility, confidence, fuzziness etc. These are … Continue reading Uncertainty: Reasoning about probability and vagueness, Prague, Sept 5-8, 2006

Sad news: Torkel Franzén has died yesterday. I've known Torkel since my undergraduate days, when he was tirelessly setting people straight on logical and philosophical matters in the newsgroup sci.logic. He wrote two wonderful books, a technical book on incompleteness (Inexhaustibility: A Non-Exhaustive Treatment) and one on misconceptions and misuses of Gödel's Theorems. He will … Continue reading Torkel Franzén

One of the corollaries that easily follow from Gödel's first incompleteness theorem for arithmetic is the incompleteness of second-order logic: there can be no proof system that generates all and only the validities of second-order logic. It follows from the incompleteness of arithmetic because for any sentences φ of first-order arithmetic, there is a sentence … Continue reading Incompleteness of Second-Order Logic

A whole bunch of conference announcements came in over the Proof Theory and FOM lists the other day:Logic Colloquium. July 27-August 2, Nijmegen, Netherlands. Submission deadline: April 17.Workshop on Hybrid Logics. August 11, Seattle (part of FLoC). Submission deadline: May 26.Computer Science Logic. September 25-29, Szeged, Hungary. Submission deadline: abstracts April 24, full papers May … Continue reading Logic Conferences

Thomas Dolby has a blog. And so do the UConn philosophy grad students.

Amazon.de emailed me today, suggesting that I preorder Kurt Gödel: The Album. There's not that much info on the amazon.de page, nor on the Vieweg page, but it's the book to accompany the exhibition the editors (Karl Sigmund, John Dawson and Kurt Mühlberger) are putting on for the Gödel Centenary in Vienna.

Don't know how I missed this: Yarden Katz has a blog, CrunchyLogic.

The new issue of the Notices of the American Mathematical Society is devoted to Kurt Gödel's life and work.

The 2006 RZ World tour just started at the "Truth and Proof" conference in Edinburgh. Thanks Jeff Ketland and Jean-Louis Hudry for putting this on and inviting me! So far we had some excellent talks by John Dawson on the history of the notion of truth and use of semantic methods in logic; by Hannes … Continue reading Truth and Proof in Edinburgh

Long time no blog. Sorry, been busy planning my 2006 world tour. Dates will be announced shortly.While you're waiting, there's a neat little piece of metamathematics that should be more widely known than it is. You all know that if T is a consistent theory satisfying the usual assumptions, then Con(T) is undecidable in T. … Continue reading Ordinal Logics

I linked to it before, but now the deadline is nigh: Call for Participation Young Scholars' Competition The Kurt Gödel Centenary: Horizons of Truth organizers and sponsors invite young scholars in logic, mathematics, physics, philosophy, computer science and theology to submit project proposals for the young scholars' competition honoring Kurt Gödels hundredth birthday. Web: http://www.logic.at/goedel2006/index.php?students … Continue reading Kurt Gödel Centenary Young Scholars’ Competition Deadline Approaching

Sad. Peter Strawson has passed away. Obits from the Times, the Telegraph, the Guardian, .

The Studia Logica special issue on cut-elimination, edited by Alex Leitsch, is out. A bunch of very interesting papers. I'm especially glad to see Alessandra Carbone publish in proof theory again! I'm a big fan.(Self-promotion: the issue also contains the final version of Georg Moser and my epsilon calculus paper. And while I'm linking, and … Continue reading Studia Logica Issue on Cut-elimination

Via OPP: Thierry Coquand's entry on Type Theory in the Stanford Encyclopedia went online a few days ago.

Brian Weatherson's Online Papers in Philosophy blog of new philosophy papers has been taken over by Jonathan Ichikawa and is now located here. So update your bookmarks/RSS feeds.Via OPP I see that Calgary's very own Rafał Urbaniak's paper on Lesniewski in the AJL is now online.