Welcome back, everyone!

This Week in Logic at CUNY:

– – – – Monday, Aug 29, 2011 – – – –

– – – – Tuesday, Aug 30, 2011 – – – –

– – – – Wednesday, Aug 31, 2011 – – – –

– – – – Thursday, Sep 01, 2011 – – – –

– – – – Friday, Sep 02, 2011 – – – –

Next Week in Logic at CUNY:

– – – – Monday, Sep 5, 2011 – – – –

– – – – Tuesday, Sep 6, 2011 – – – –

Fall Semester 2011,

Computational Logic Seminar

Room TBD, 2:00 – 4:00 PM,

September 6, 2011

Speaker: Sergei Artemov (Graduate Center CUNY)

Title: Toward first-order justification logic I.

Abstract: We will study first-order logic of proofs FOLP and outline first-order justification logic. In part I of this talk, we will revisit the Brouwer-Heyting-Kolmogorov semantics as the principal motivation and introduce FOLP in its current “official” form.

– – – – Wednesday, Sep 7, 2011 – – – –

– – – – Thursday, Sep 8, 2011 – – – –

– – – – Friday, Sep 9, 2011 – – – –

Model Theory Seminar

Friday, September 9, 2011 12:30 pm GC 6417

Professor Roman Kossak (The City University of New York)

Models and types of PA, I

Abstract. Various types of arithmetic types will be defined and their properties discussed. The goal is to prove that each completion of PA has continuum many independent unbounded indiscernible types.

Logic Workshop

Friday, September 9, 2011 2:00 pm GC 6417

Professor David Marker (University of Illinois at Chicago) Zilber’s exponential field

Abstract. There are a number of basic but notoriously difficult open questions about definability in the complex field with exponentiation. Zilber constructed a non-elementary class of algebraically closed exponential fields, proved that the class is categorical in

uncountable powers and showed that definable sets behave well in this class. This leads one to ask if the complex field with exponentiation is the unique model in this class of size continuum. I will survey a number of results around this question.

Seminar in Logic and Games

Friday, September 9, 2011

** Two talks today **

CUNY Graduate Center, room 4419

4:15 PM

FILLING IN THE FOUNDATIONS OF PROBABILITY

ARTHUR PAUL PEDERSEN

Carnegie Mellon University

Abstract. This talk focuses on the foundations of probability, paying particular attention to justiﬁcations for possessing degrees of belief conforming to probabilities. Broadly speaking, these justiﬁcations can be divided into four categories: Representation Arguments (Ramsey [1926], Savage [1954]), Axiomatic Arguments (Cox [1946], Aczel [1966]), ´ Forecasting or Calibration Arguments (de Finetti [1974], Savage [1971]), and Dutch Book Arguments (de Finetti [1937], Shimony [1955]). Dutch Book Arguments have received the most attention—indeed, they have become a tradition in probability for furnishing

foundations—and they will receive more attention in this talk.

I will review the classic Dutch Book Argument due to de Finetti [1937], some well-known difﬁculties for the argument, and other difﬁculties for the argument which have received less attention. I will then review work which tries to ameliorate some of the problems we discuss.

I will thereupon consider a Dutch Book Argument advanced by way of a compelling notion of coherence, circumventing some of these problems. The notion of coherence ties in nicely with the work of van Fraassen [1995], Arlo-Costa and Parikh [2005], and Leitgeb [2010]. So-called core systems, which form the basis of this work, play a crucial role in the reduction of qualitative epistemic notions to quantitative epistemic notions. After brieﬂy reviewing core systems, we will see how qualitative aspects of core systems may be invoked in a Dutch Book Argument for possessing degrees of belief conforming to probabilities. Finally, we evaluate the argument. Parts of this talk address some of the issues I will touch upon at

Progic and so would be useful to acquire additional background.

5 PM

Meaning shifts and Conditioning

Jan-Willem Romeijn (University of Groningen)

Abstract: This paper investigates the viability of the Bayesian model of belief change. Van Benthem (2003) has shown that a particular kind of information change typical for dynamic epistemic logic cannot be modelled by Bayesian conditioning. I argue that the problems described by van Benthem come about because the information change alters the semantics in which the change is supposed to be modelled by

conditioning: it induces a shift in meanings. I then show that meaning shifts can be modelled in terms of conditioning by employing a semantics that makes these changes in meaning explicit, and that the appropriate probability kinematics can be described by Dempster’s rule. The new model thereby facilitates a better understanding between probabilistic epistemology and dynamic epistemic logic.

There will be a wine and cheese reception in room 4421 after the second talk.

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The majority of this information, including an interactive calendar of future events, can be found at our website:

http://nylogic.org/Calendar