We have an ever expanding domain of applications of logic: in mathematics, in philosophy, computer science, linguistics, cognitive science, and social science. More and more fields demand logical analysis.

Professor Sara Negri, delivering the 2019 Annual Logic Lecture

### News

## Open Position: Assistant Research Professor in Philosophical Logic

## Logic Group’s Statement on Black Lives Matter

The UConn Logic Group, as a founding and principal member of the Logic Supergroup, is a co-signatory on the Supergroup’s recent Statement on Black Lives Matter. The full statement appears below. Statement from the Logic Supergroup organizers on Black Lives Matter The killings of George Floyd and Breonna Taylor by police have resulted in deep […]

[Read More]## Online Truth Conference

This might interest you: TRUTH 20/20 — an online conference, July 27 – August 6, 2020. http://tinyurl.com/truth-conference-2020

[Read More]## Logic Group videos and new Logic Supergroup channel

There are number of new recordings of UConn Logic Group colloquium talks on our youtube channel. We are also introducing playlists: for example, for last year’s “If” by any other name workshop here, or the recordings of the SEP 2018 conference (which was hosted by the UConn Logic Group) here. We’re also happy to announce […]

[Read More]## Leitgeb talk video online

The recording of Hannes Leitgeb’s talk “On the Logic of Vector Space Models” in the Logic Supergroup online colloquium can now be found on our youtube channel.

[Read More]## Online Logic Supergroup!

We’re co-organizing a series of online colloquia. Currently six nine fourteen sixteen (I stopped counting) logic groups, programs, centers, institutes, … from around the globe are participating. Go here for details: https://logic.uconn.edu/supergroup/

[Read More]## Postponed: Abstractionism 2 conference

See here.

[Read More]## Logic Certificate (and Damir D. Dzhafarov) featured in UConn Today

Logic, a Common Thread at UConn

[Read More]## 2019 Workshop: “If” by any other name

UConn Logic Group Workshop, April 6-7, 2019 “If” by any other name It is a relatively recent development that research on conditionals is taking a deep and sustained interest in the full range of linguistic markers, their interactions with each other and with other linguistic categories, and the ways in which they drive and constrain […]

[Read More]## UConn Logic Group Launches New Certificate Program

The Logic Group is pleased to announce that the Graduate Certificate in Logic is now accredited—which means that we can start awarding it! A website explaining the certificate in detail is in the works. We hope to have this up by the time the new semester starts. In the meantime, here is a rough summary: […]

[Read More]### This Semester

- 2/18
*UConn AWM Presents*

Screening Of "Julia Robinson And Hilbert's Tenth Problem"#### UConn AWM Presents

Thursday, February 18th, 2021

Screening Of "Julia Robinson And Hilbert's Tenth Problem"

5:00 PM - 6:30 PM

Storrs Campus

ZoomA special screening of George Csicsery's film "Julia Robinson and Hilbert's Tenth Problem", part one of a two-day event celebrating the life and mathematical legacy of Julia Robinson.

Presented by the UConn Chapter of the Association for Women in Mathematics. Supported by UConn Library.

More info, and to register: https://awm.math.uconn.edu/julia-robinson-film-screening/

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 2/19
*Logic Colloquium*

Contextual Analysis, Epistemic Probabilities, And Paradoxes

Ehtibar Dzhafarov (Purdue)#### Logic Colloquium

Friday, February 19th, 2021

Contextual Analysis, Epistemic Probabilities, And Paradoxes

Ehtibar Dzhafarov (Purdue)

10:00 AM - 11:30 AM

Storrs Campus

ZoomContextual analysis deals with systems of random variables. Each random variable within a system is labeled in two ways: by its content (that which the variable measures or responds to) and by its context (conditions under which it is recorded). Dependence of random variables on contexts is classified into (1) direct (causal) cross-influences and (2) purely contextual (non-causal) influences. The two can be conceptually separated from each other and measured in a principled way. The theory has numerous applications in quantum mechanics, and also in such areas as decision making and computer databases. A system of deterministic variables (as a special case of random variables) is always void of purely contextual influences. There are, however, situations when we know that a system is one of a set of deterministic systems, but we cannot know which one. In such situations we can assign epistemic (Bayesian) probabilities to possible deterministic systems, create thereby a system of epistemic random variables, and subject it to contextual analysis. In this way one can treat, in particular, such logical antinomies as the Liar paradox. The simplest systems of epistemic random variables describing the latter have no direct cross-influences and the maximal possible degree of purely contextual influences.

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 2/19
*UConn AWM Presents*

Public Lecture

Carol Wood (Wesleyan)#### UConn AWM Presents

Friday, February 19th, 2021

Public Lecture

Carol Wood (Wesleyan)

3:00 PM - 4:00 PM

Storrs Campus

Zoom (registration required)Please join us for a university public lecture by Carol Wood, Edward Burr Van Vleck Professor of Mathematics, Emerita, at Wesleyan University, part two of a two-day event celebrating the life and mathematical legacy of Julia Robinson.

Presented by the UConn Chapter of the Association for Women in Mathematics. Supported by UConn Library.

More info, and to register: https://awm.math.uconn.edu/julia-robinson-film-screening/

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 2/26
*Logic Colloquium*

On Abstraction Principles

Paolo Mancosu (Berkeley)#### Logic Colloquium

Friday, February 26th, 2021

On Abstraction Principles

Paolo Mancosu (Berkeley)

4:00 PM - 5:30 PM

Storrs Campus

ZoomJoin us for a talk by Paolo Mancosu (UC Berkeley):

"The company you keep: Some recent results on neo-logicism and abstraction principles"

In this talk I will provide an overview of my recent investigations, some published some unpublished, on neologicism and in particular on the topics related to the good company and the bad company objections.

Please contact us for log-in information.

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 3/12
*Logic Colloquium*

Social Spheres

Gillian Russell (ACU Melbourne)#### Logic Colloquium

Friday, March 12th, 2021

Social Spheres

Gillian Russell (ACU Melbourne)

10:00 AM - 11:30 AM

Storrs Campus

ZoomAbstract: This paper adapts Lewis’ “Ptolemaic Astronomy” from Counterfactuals for use in thinking about social hierarchy and subordination.

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 3/19
*Logic Colloquium*

A More Unified Approach to Free Logics

Edi Pavlović (Helsinki)#### Logic Colloquium

Friday, March 19th, 2021

A More Unified Approach to Free Logics

Edi Pavlović (Helsinki)

11:00 AM - 12:30 PM

Storrs Campus

ZoomEdi Pavlović (Helsinki)

A More Unified Approach to Free Logics

(joint work with Norbert Gratzl. MCMP, Munich)

Free logics is a family of first-order logics which came about as a result of examining the existence assumptions of classical logic. What those assumptions are varies, but the central ones are that (i) the domain of interpretation is not empty, (ii) every name denotes exactly one object in the domain and (iii) the quantifiers have existential import. Free logics usually reject the claim that names need to denote in (ii), and of the systems considered in this paper, the positive free logic concedes that some atomic formulas containing non-denoting names (including self-identity) are true, while negative free logic rejects even the latter claim.

These logics have complex and varied axiomatizations and semantics, and the goal of the present work is to offer an orderly examination of the various systems and their mutual relations. This is done by first offering a formalization, using sequent calculi which possess all the desired structural properties of a good proof system, including admissibility of contraction and cut, while streamlining free logics in a way no other approach has. We then present a simple and unified system of generalized semantics, which allows for a straightforward demonstration of the meta-theoretical properties, while also offering insights into the relationship between different logics (free and classical). Finally, we extend the system with modalities by using a labeled sequent calculus, and here we are again able to map out the different approaches and their mutual relations using the same framework.

Zoom

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 3/19
*Meaning Group: del Prete and Zucchi 2020*#### Meaning Group: del Prete and Zucchi 2020

Friday, March 19th, 2021

1:00 PM - 2:00 PM

Storrs Campus

onlineThe Meaning Group will meet online on Friday, March 19, 1-2pm. We will be discussing the paper “Gender in Conditionals” by Fabio del Prete and Sandro Zucchi (Linguistics and Philosophy 2020).

We will hold the meeting via video conference. For the link to access the session, please refer to the Meaning Group email or contact the organizers.

The UConn Meaning Group meets on a regular (mostly weekly) basis throughout the academic year to discuss recent and ongoing work in the areas of Semantics, Pragmatics, and Philosophy of Language.

Follow the link below for details and contact information.

Contact Information: stefan.kaufmann@uconn.edu More - 4/2
*Logic Colloquium*

Logic Done as if Inference in Language Mattered

Larry Moss (Indiana University)#### Logic Colloquium

Friday, April 2nd, 2021

Logic Done as if Inference in Language Mattered

Larry Moss (Indiana University)

2:00 PM - 3:30 PM

Storrs Campus

ZoomOur topic is logical inference in natural language, as it is done by people and computers.

The first main topic will be monotonicity inference, arguably the best of the simple ideas

in the area. Monotonicity can be incorporated in running systems whereby one can take

parsed real-life sentences and see simple inferences in action. I will present some of the

theory, related to higher-order monotonicity and the syntax-semantics interface offered by

categorial grammar.

In a different direction, these days monotonicity inference can be done by machines as well

as humans. The talk also discusses this development along with some ongoing work on the

borderline of natural logic and machine learning.

The second direction in the talk will be an overview of the large number of logical systems for

various linguistic phenomena. This work begins as an updating of traditional syllogistic logic,

but with much greater expressive power.

Overall, the goal of the talk is to persuade you that the research program of "natural logic"

leads to a lively research area with connections to many areas both inside and outside of more

mainstream areas of logic.

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 4/9
*Logic Colloquium*

Interacting Alternatives: Referential Indeterminacy And Questions

Floris Roelofsen (ILLC Amsterdam)#### Logic Colloquium

Friday, April 9th, 2021

Interacting Alternatives: Referential Indeterminacy And Questions

Floris Roelofsen (ILLC Amsterdam)

10:00 AM - 11:30 AM

Storrs Campus

ZoomOne of the major challenges involved in developing semantic theories is that many constructions in natural language given rise to alternatives. Different sources of alternatives have been identified---e.g., questions, indeterminacy, focus, scalarity---and have been investigated in quite some depth. Less attention, however, has been given so far to the question how these different kinds of alternatives interact. I will focus in this talk one one such interaction, namely between referential indeterminacy and questions. Several formal semantic frameworks have been developed to capture referential indeterminacy (dynamic semantics, alternative semantics) and the content of questions (e.g., alternative semantics, structured meanings, partition semantics, inquisitive semantics). I will report on ongoing work with Jakub Dotlacil, which aims to merge dynamic and inquisitive semantics in a principled way. I will present a basic system and suggest some potential applications and extensions.

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 4/16
*Annual Logic Lecture*

Algebraic Constructions In Models Of Peano Arithmetic And Its Weak Fragments

Paola D’Aquino (Università della Campania)#### Annual Logic Lecture

Friday, April 16th, 2021

Algebraic Constructions In Models Of Peano Arithmetic And Its Weak Fragments

Paola D’Aquino (Università della Campania)

10:00 AM - 11:30 AM

Storrs Campus

ZoomProfessor D’Aquino is the UConn Logic Groups 2020/2021 Scholar of Consequence, and will deliver the Annual Logic Lecture.

Abstract: I will concentrate on the ideal theory of models of Peano Arithmetic and some of its weak fragments. I will present a model theoretic analysis of the residue rings of these structures.

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 4/23
*Logic Colloquium*

Bilateralist Truth-Maker Semantics for ST, TS, LP, K3, ...

Ulf Hlobil (Concordia University)#### Logic Colloquium

Friday, April 23rd, 2021

Bilateralist Truth-Maker Semantics for ST, TS, LP, K3, ...

Ulf Hlobil (Concordia University)

10:00 AM - 11:30 AM

Storrs Campus

ZoomBilateralist Truth-Maker Semantics for ST, TS, LP, K3, ...

Ulf Hlobil, Concordia University, Montreal, Canada

Abstract:

The talk advocates a marriage of inferentialist bilateralism and truth-maker bilateralism. Inferentialist bilateralists like Restall and Ripley say that a collection of sentences, Y, follows from a collection of sentences, X, iff it is incoherent (or out-of-bounds) to assert all the sentences in X and, at the same time, deny all the sentences in Y. In Fine’s truth-maker theory, we have a partially ordered set of states that exactly verify and falsify sentences, and some of these states are impossible. We can think of making-true as the worldly analogue of asserting, of making-false as the worldly analogue of denying, and of impossibility as the worldly analogue of incoherence. This suggests that we may say that, in truth-maker theory, a collection of sentences, Y, follows (logically) from a collection of sentences, X, iff (in all models) any fusion of exact verifiers of the members of X and exact falsifiers of the member of Y is impossible. Under routine assumptions about truth-making, this yields classical logic. Relaxing one such assumption yields the non-transitive logic ST. Relaxing another assumption yields the non-reflexive logic TS. We can use known facts about the relation between ST, LP, and K3, to provide an interpretation of LP as the logic of falsifiers and K3 as the logic of verifiers. The resulting semantics for ST is more flexible than its usual three-valued semantics because it allows us, e.g., to reject monotonicity. We can also recover fine-grained logics, like Correia’s logic of factual equivalence.

All welcome!

Please contact us for the Zoom log-in information.

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 4/30
*Logic Colloquium*

Impossibilities without impossibilia

Bjørn Jespersen (Utrecht)#### Logic Colloquium

Friday, April 30th, 2021

Impossibilities without impossibilia

Bjørn Jespersen (Utrecht)

10:00 AM - 11:30 AM

Storrs Campus

ZoomJoin us for this week's Logic Colloquium!

Bjørn Jespersen (Utrecht)

"Impossibilities without impossibilia"

Circumstantialists already have a logical semantics for impossibilities. They expand their logical space of possible worlds by adding impossible worlds. These are impossible circumstances serving as indices of evaluation, at which impossibilities are true. A variant of circumstantialism, namely modal Meinongianism, adds impossible objects as well. The opposite of circumstantialism, namely structuralism, has some catching-up to do. What might a structuralist logical semantics without impossible worlds or impossible objects look like? This paper makes a structuralist counterproposal. I present a semantics based on a procedural interpretation of the typed l-calculus. The fundamental idea is that talk about impossibilities should be construed in terms of procedures yielding as their product a condition that could not possibly have a satisfier, or else failing to yield a product at all. Dispensing with a ‘bottom’ of impossibilia requires instead a ‘top’ consisting of structured hyperintensions, intensions, intensions defining other intensions, a typed universe, and dual predication. I explain how the theory works by going through a couple of cases.

Zoom

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More - 5/7
*Logic Colloquium*

Minimal Change Theories Of Conditionals, The Import-Export Law, And Modus Ponens

Alessandro Zucchi (University Of Milan)#### Logic Colloquium

Friday, May 7th, 2021

Minimal Change Theories Of Conditionals, The Import-Export Law, And Modus Ponens

Alessandro Zucchi (University Of Milan)

10:00 AM - 11:30 AM

Storrs Campus

ZoomJoin us for the Logic Colloquium!

Alessandro Zucchi (University of Milan, La Statale)

"Minimal change theories of conditionals, the import-export law, and modus ponens"

Stalnaker's minimal change semantics for conditionals fails to support the import-export law, according to which (a) and (b) are logically equivalent:

(a) if A, then if B, then C

(b) if A and B, then C

However, natural language conditionals seem to abide by the law. McGee (1985) outlines a minimal change semantics for conditionals that supports it. I argue that, in fact, the equivalence between (a) and (b) does not hold unrestrictedly, and I suggest that the facts follow from the interaction between the semantics of conditionals and the ways suppositions may affect the context. I conclude by describing the consequences of my account for the issue of the validity of modus ponens.

Zoom

https://logic.uconn.edu/calendar/

Contact Information: Damir Dzhafarov, damir@math.uconn.edu More