SEPTEMBER 19th, 2016, LogiCIC-LIRa Seminar
Speaker: Branden FitelsonDate and Time: Monday, September 19th 2016, 11:00 – 12:30.
Venue: ILLC Seminar Room F1.15, Science Park 107.
Title: Two New(ish) Triviality Results for Indicative Conditionals.
Abstract. I will do two things in this talk: (1) present an axiomatic generalization of Gibbard’s (logical) triviality result for indicative conditionals, and (2) present an algebraic strengthening of Lewis’s (probabilistic) triviality result for indicative conditionals. Both results start from a very weak background theory (either logical or probabilistic) of the indicative conditional, and (relative to these weak backgrounds) both results will rely only on the so-called Import-Export Law. So, these results can be viewed as (general, and strong) “odd consequences” of Import-Export.
LIRa/LogiCIC Lecture Series with Eric Pacuit
June 1st - June 15th 2016
Eric Pacuit (University of Maryland) will give a LIRa/LogiCIC Lecture Series between June 1st and June 15th 2016 on Neighborhood Semantics for Modal Logic. Everyone is welcome to attend the lectures. Students in the Master of Logic can subscribe to the lecture series and take part in the exercise sessions for a June Project. For more details an the full schedule, see the MSc Logic website.
MAY 13th, 2016, LogiCIC-LIRa Seminar
Speaker: Guido Bacciagaluppi
Date and Time: Friday, May 13th 2016, 13:00 – 14:30.
Venue: ILLC Seminar Room F1.15, Science Park 107.
Title: Von Neumann’s no-Hidden-Variables Theorem (and Hermann’s Critique).
Abstract. There has been some recent debate about what von Neumann intended with his famous no-hidden-variables theorem (from his 1932 book), and on whether Bell’s now equally famous criticism is really fair to von Neumann. I revisit von Neumann’s result, which was originally published in 1927 in a paper trying to give what one would now call a “reconstruction” of quantum mechanics, and suggest a more nuanced reading. I pay special attention also to the critique of von Neumann provided by Grete Hermann in her 1935 essay on the foundations of quantum mechanics (and in an unpublished manuscript from 1933).
APRIL 29th, 2016, LogiCIC-LIRa Seminar
Speaker: Rohit Parikh
Date and Time: Friday, April 22nd 2016, 13:00 – 14:30.
Venue: ILLC Seminar Room F1.15, Science Park 107.
Title: Influencing behavior by influencing beliefs.
Abstract. Agents act on the basis of their preferences and their beliefs. These include beliefs both about the world and about the actions of other agents.
By influencing the beliefs of agents we can also influence what choices they make. The influence need not involve deception but may simply involve withholding or offering certain truths.We show that for a finite set of agents who know nothing about some proposition, an arbitrary state of information can be achieved by sending an n-tuple of signals, one to each agent. We consider how this will influence the actions of cautious (risk averse) or aggressive (risk loving) agents.
We next consider the case of a candidate campaigning for election who seeks the approval of voters. What sorts of things can she say to increase their approval? And is it possible to increase approval while, at the same time losing votes? We show that it is always possible to increase net approval but that this can result in losing votes.
APRIL 22nd, 2016, LogiCIC-LIRa Seminar
Speaker: Rohit Parikh
Date and Time: Friday, April 22nd 2016, 16:00 – 17:30.
Venue: ILLC Seminar Room F1.15, Science Park 107.
Title: An Epistemic Generalization of Rationalizability.
Abstract. Savage showed us how to infer an agent’s subjective probabilities and utilities from the bets which the agent accepts or rejects. But in a game theoretic situation an agent’s beliefs are not just about the world but also about the probable actions of other agents which will depend on their, beliefs and utilities. Moreover, it is unlikely that agents know the precise subjective probabilities or cardinal utilities of other agents. An agent is more likely to know something about the preferences of other agents and something about their beliefs. In view of this, the agent is unlikely to to have a precise best action which we can predict, but is more likely to have a set of “not so good” actions which the agent will not perform.
Ann may know that Bob prefers chocolate to vanilla to strawberry. She is unlikely to know whether Bob will prefer vanilla ice cream or a 50-50 chance of chocolate and strawberry. So Ann’s actions and her beliefs need to be understood in the presence of such partial ignorance. We propose a theory which will let us decide when Ann is being irrational, based on our partial knowledge of her beliefs and preferences, and assuming that Ann is, rational, how to infer her beliefs and preferences from her actions.Our principal tool is a generalization of rational behavior in the context of ordinal utilities and partial knowledge of the game which the agents are playing.
APRIL 22nd, 2016, LogiCIC-LIRa Seminar
Speaker: Jon Williamson
Date and Time: Friday, April 22nd 2016, 13:00 – 14:30.
Venue: ILLC Seminar Room F1.15, Science Park 107.
Title: Inductive Logic for Automated Decision Making.
Abstract. According to Bayesian decision theory, one’s acts should maximise expected utility. To calculate expected utility one needs not only the utility of each act in each possible scenario but also the probabilities of the various scenarios. It is the job of an inductive logic to determine these probabilities, given the evidence to hand. The most natural inductive logic, classical inductive logic, attributable to Wittgenstein, was dismissed by Carnap due to its apparent inability to capture the phenomenon of learning from experience. I argue that Carnap was too hasty to dismiss this logic: classical inductive logic can be rehabilitated, and the problem of learning from experience overcome, by appealing to the principles of objective Bayesianism. I then discuss the practical question of how to calculate the required probabilities and show that the machinery of probabilistic networks can be fruitfully applied here. This culminates in an objective Bayesian decision theory that has a realistic prospect of automation.
APRIL 15th, 2016, LogiCIC-LIRa Seminar
Speaker: Jeffrey M. Keisler
Date and Time: Friday, April 15th 2016, 13:00 – 14:30.
Venue: ILLC Seminar Room F1.15, Science Park 107.
Title: Observing, reporting and deciding in networks of agents.
Abstract. We define an observation network as a network of agents who each have a vocabulary, a knowledge base in first-order logic, and a set of potential observations. Agents can make inferences and report them to other agents to whom they are linked, but communication is restricted to the common vocabulary of the reporter and recipient. Agents add to their knowledge bases by making observations, receiving reports from other agents, and making inferences, and share useful statements with other agents who have different vocabularies.
The focus of the presentation will be on explanation, interpretation and application of the framework and results, rather than on their derivation. Observation networks are general enough to model many situations. We conclude by considering the example of junction tree algorithms for solving Bayes nets.
Joint work with H. Jerome Keisler, University of Wisconsin.
Biography. Jeffrey Keisler is currently Visiting Professor and Fulbright Distinguished Chair in the Mathematics and Systems Analysis Department at Aalto University in Helsinki. A Professor of Management Information Systems at the University of Massachusetts Boston, he has two books and over fifty journal articles and book chapters in decision analysis and related fields. Professor Keisler is past-President of the INFORMS Decision Analysis Society and has received its Publication Award. His PhD in Decision Sciences is from Harvard University. He will present joint work with H. Jerome Keisler who has been a leader of mathematical logic for over fifty years.
APRIL 8th, 2016, LogiCIC-LIRa Seminar
Speaker: Elias Tsakas
Date and Time: Friday, April 8th 2016, 13:00 – 14:30.
Venue: ILLC Seminar Room F1.15, Science Park 107.
Title: Reasonable Doubt Revisited.
Abstract. According to the common definition, the standard of reasonable doubt is a threshold such that, the defendant is convicted if and only if the probability that the juror attaches to the defendant being guilty is above this threshold. In this paper we prove that generically such a threshold exists if and only if the juror reasons only about the defendant’s guilt and nothing else. We discuss the implications of this result, and subsequently we propose a weakening of the aforementioned definition, by substituting the standard of reasonable doubt with a pair of standards, an upper and a lower one, thus obtaining a sufficient condition for conviction and a sufficient condition for acquittal. Finally, we prove that the lower standard always exists, whereas the upper standard exists if and only if the juror prefers to always convict a guilty defendant, irrespective of the circumstances.
March 22nd, 2016, LogiCIC-LIRa Workshop
“Logical Dynamics of Social Influence and Information Change”
Oudemanhuispoort 4-6, C1.23
Amsterdam, The Netherlands
from 14:00 to 18:00
The Workshop “Logical Dynamics of Social Influence and Information Change” will address a number of new developments in which formal methods are used to model phenomena that play a central role in epistemic-social contexts. In particular we focus on modeling agents’ epistemic and doxastic attitudes, the change of such attitudes as well as their communication-based interactions.
The following two themes will receive special attention: The first theme refers to the concept of social influence. In this context we use logic to model the spread of opinions, the exchange of information and the distribution of behavior in a social network. The second theme refers to the logical mechanism of information change as triggered by events, such as e.g. observations, communication as well as steps of logical inference.
The workshop is associated with the PhD defence of Zoé Christoff.
For more information, see https://ldsiic.wordpress.com/.
September 10th, 2015, LogiCIC-LIRa Workshop
From Modal and Non-Classical Logics to the Mathematics of Quantum Information Flow
ILLC Seminar Room
F1.15, Science Park 107,
Amsterdam, The Netherlands
The aim of this workshop is to create a forum to present new developments, exchange ideas, explore and establish new connections between logic, mathematics, computer science and physics.
Topics include the following list but are not restricted to: modal logic, non-classical logic, spatial logic, mathematical structures in logic, quantum computation and quantum information, the foundations of quantum theory.
This workshop is associated with the PhD defense of Shengyang Zhong.
For more information, see https://workshop20150910.wordpress.com/.
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Olivier Roy (Abstract)
Title: TBALocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Davide Grossi (Abstract)
Title: Spreading Gossip EpistemicallyLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Thomas Bolander (Abstract)
Title: Complexity Results in Epistemic PlanningLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Christian List (Abstract)
Title: From Degrees of Belief to Beliefs: Lessons from Judgment-Aggregation TheoryLocation: Science Park 904, Room B0.207, Amsterdam -
Hans van Ditmarsch (Abstract)
Title: Five Funny BisimulationsLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Roberto Ciuni (Abstract)
Title: Plausibility Trees and Simple FutureLocation: Science Park 107, room F1.15 -
Soroush Rafiee Rad (Abstract)
Title: Forming Rational Belief From First Order Probabilistic EvidenceLocation: Science Park 107, room F1.15 -
various speakers (Abstract)
Title: The Workshop on Correlated Information Change -
various speakers (Abstract)
Title: The Synthese conference on Qualitative and Quantitative Methods in Formal Epistemology -
Various Speakers (Abstract)
Title: MINI-WORKSHOP on The Logical Dynamics of Information, Agency and InteractionLocation: Science Park 107, room F1.15 -
Thomas Icard (Stanford University) (Abstract)
Title: Comparative Probability in Language and ActionLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Thomas Ågotnes (University of Bergen) (Abstract)
Title: From Distributed to Common KnowledgeLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Jeremy Seligman (University of Auckland) (Abstract)
Title: Exploiting and maintaining network IgnoranceLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Jason Konek, Ben Levinstein, Krzysztof Mierzewski (Abstract)
Title: LogiCIC/LIRa mini-workshop on Formal EpistemologyLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Branden Fitelson (Rutgers University) (Abstract)
Title: LIRa-affiliated event: Tutorial on CoherenceLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Branden Fitelson (Rutgers University) (Abstract)
Title: LIRa-affiliated event: Tutorial on CoherenceLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Branden Fitelson (Rutgers University) (Abstract)
Title: LIRa-affiliated event: Tutorial on CoherenceLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Bryan Renne (University of Amsterdam/University of British Columbia), http://bryan.renne.org/ (Abstract)
Title: Dynamic Justification Logic for Formal EpistemologyLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Francesca Poggiolesi (CNRS-CEPERC) (Abstract)
Title: An alternative proof-theoretical approach to standard conditional logicsLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Brian Hill (CNRS-GREGHEC) (Abstract)
Title: Confidence in Beliefs and Decision MakingLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Vincent Hendricks (University of Copenhagen) (Abstract)
Title: Science BubblesLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Barteld Kooi (University of Groningen) (Abstract)
Title: The ambiguity of knowabilityLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Rohit Parikh (Brooklyn College and CUNY Graduate Center) (Abstract)
Title: Knowledge from Inadvertant and Strategic CommunicationLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Sven Ove Hansson (Royal Institute of Technology, Stockholm) (Abstract)
Title: Descriptor revision and epistemic accessibilityLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Rasmus Rendsvig (University of Amsterdam) (Abstract)
Title: DEL-based state machines and their application in modeling group reasoning and choiceLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Emiliano Lorini (IRIT-CNRS, University of Toulouse) (Abstract)
Title: On the epistemic foundation for iterated weak dominance: an analysis in a logic of individual and collective attitudesLocation: Room F1.15, ILLC, Science Park 107, Amsterdam -
Fenrong Liu (Tsinghua University) (Abstract)
Title: Facebook and the epistemic logic of friendshipLocation: Science Park 107 (new ILLC location), Room F1.15 -
Marcel Boumans (Abstract)
Title: Rational consensus of expert judgments in economicsLocation: Room F1.15, Science Park 107, Amsterdam -
Giacomo Sillari (Abstract)
Title: You better play 7: mutual versus common knowledgeof advice in a weak-link experimentLocation: Room TBA, Science Park 904, Amsterdam -
Mamoru Kaneko (Tsukuba University) (Abstract)
Title: Epistemic Logic and Inductive Game TheoryLocation: Room D1.115, Science Park 904, Amsterdam -
Janusz Czelakowski (Abstract)
Title: Freedom and Enforcement in Action - Elements of Formal Action theoryLocation: Room C1.112, Science Park 904, Amsterdam -
Thomas Bolander and Hans van Ditmarsch (Abstract)
Title: Title TBALocation: Room B0.201, Science Park 904, Amsterdam -
Rohit Parikh (CUNY) (Abstract)
Title: Epistemic Logic in Real Life and LiteratureLocation: Room D1.113, Science Park 904, Amsterdam -
Daisuke Bekki and Valentin Goranko (Abstract)
Title: Dependent type semantics: the framework (Bekki, 15:00-) / Modeling the Dynamics of Information and Abilities of Players in Multi-Player Games (Goranko, 16:30-)Location: Room A1.04, Science Park 904, Amsterdam -
Valentin Goranko (Abstract)
Title: Logics for multi-agent systemsLocation: Science Park 904, Amsterdam -
Guillaume Aucher (IRISA/INRIA) (Abstract)
Title: DEL-sequents for progression, regression and epistemic planningLocation: Science Park, G0.05 -
Guillaume Aucher (Abstract)
Title: Privacy and Epistemic ObligationsLocation: Room B0.201, Science Park 904, Amsterdam -
Nuel Belnap (University of Pittsburgh) (Abstract)
Title: On internal cases in case-intensional logicLocation: Room D1.114, Science Park 904, Amsterdam -
Branden Fitelson (Rutgers University, New Brunswick) (Abstract)
Title: Accuracy, Coherence, and EvidenceLocation: Room D1.113, Science Park 904, Amsterdam -
Vincent Hendricks (Abstract)
Title: Infobombs in Echo-chambersLocation: Room A1.04, Science Park 904, Amsterdam -
Maria Louisa Dalla Chiara (Florence) and Roberto Giuntini (Cagliari) (Abstract)
Title: From Quantum Information to Musical SemanticsLocation: Room A1.10, Science Park 904, Amsterdam -
Robterto Giuntini (University of Cagliari) (Abstract)
Title: The logic of unsharp quantum mechanicsLocation: Room B0.203, Science Park 904, Amsterdam -
Roberto Giuntini (University of Cagliari) (Abstract)
Title: The Logics of Quantum Computation: An IntroductionLocation: Room varies, Science Park 904, Amsterdam -
Kevin T. Kelly and Hanti Lin (Abstract)
Title: Propositional Reasoning that Tracks Probabilistic Reasoning / Uncertain Acceptance and Contextual Dependence on QuestionsLocation: Room A1.10, Science Park 904, Amsterdam