Essential Structure and Apt Causal Models (Jennifer McDonald)

The Logic and Metaphysics Workshop will meet on December 7th from 4:15-6:15 (NY time) via Zoom for a talk by Jennifer McDonald (CUNY).

Title: Essential Structure and Apt Causal Models

Abstract: A promising account of actual causation – the causal relation holding between two token events – uses the language of structural equation models (SEMs). Such an account says, roughly, that actual causation holds between two token events when there is a suitable model according to which (1) the two events occur; and (2) intervening on the model to change the value of the variable that represents the cause changes the value of the variable that represents the effect (Halpern & Pearl, 2005; Hitchcock, 2001; Weslake, 2015; Woodward, 2003). Of course, this calls for an account of when a model is suitable – or, apt. Although initially bracketed, this issue is increasingly pressing; in part due to the recently discovered problem of structural isomorphs (Hall 2007; Hitchcock 2007a; Blanchard and Schaffer 2017; Menzies 2017). This paper offers a unified analysis of two aptness requirements from the literature – those enjoining us to include essential structure and avoid unstable models. While successfully invoked by Blanchard and Schaffer (2017) to resolve the problem of structural isomorphs, these requirements are unilluminating as they stand. My paper synthesizes them into a single aptness requirement that, I claim, gets to the heart of what’s representationally required of a causal model for capturing actual causation.

ST and All That: Philosophical Issues

Following the recent workshop, Substructural Logic, Hierarchies Thereof, and Solutions to the Liar (October 30th, 2020), the Logic and Metaphysics Workshop and the Saul Kripke Center shall host ST and All That: Philosophical Issues, a roundtable discussion considering the philosophical implications of this technical work. The meeting will happen on Monday, December 14th, 2020, from 4:15 to 6:15 pm (NY time). Four panelists will speak for 15 minutes each addressing (at least) the following questions:

* What do we learn about the nature of logic from ST and its hierarchy?

* What do we learn about solutions to the liar from ST and its hierarchy?

There will then be an open discussion for all present. The panelists will be: Shay Logan (Kansas State), Federico Pailos (Buenos Aires), Dave Ripley (Monash), and Chris Scambler (NYU).

Talks will be on Zoom, and are open to all interested. A link will be sent out on the mailing lists of the Logic and Metaphysics Workshop and the Saul Kripke Center not later than the day before. People not on either of those lists who want to receive the link should email Graham Priest (priest DOT graham AT gmail DOT com). PLEASE FEEL FREE TO PASS ON THIS ANNOUNCEMENT.

A Free Logic for Fictionalism (Mircea Dumitru)

The Logic and Metaphysics Workshop will meet on November 30th from 4:15-6:15 (NY time) via Zoom for a talk by Mircea Dumitru (Bucharest).

Title: A Free Logic for Fictionalism

Abstract: In Reference without Referents, Mark Sainsbury aims to provide an account of reference that honours the common-sense view that sentences containing empty names like “Sherlock Holmes”, “Vulcan”, and “Santa Claus” are entirely intelligible, and that many such sentences — “Vulcan doesn’t exist”, “Many children believe that Santa Claus will give them presents at Christmas”, etc.— are literally true. Sainsbury’s account endorses the Davidsonian program in the theory of meaning, and combines this with a commitment to Negative Free Logic, which holds that all simple sentences containing empty names are false. In my talk, I pose a number of problems for this account. In particular, I question the ability of Negative Free Logic to make appropriate sense of the truth of familiar sentences containing empty names, including negative existential claims like “Vulcan doesn’t exist”.

Note: this is based on joint work with Frederick Kroon (Auckland).

How to Abū Hāšim Meinong (Behnam Zolghadr)

The Logic and Metaphysics Workshop will meet on November 23rd from 4:15-6:15 (NY time) via Zoom for a talk by Behnam Zolghadr (LMU Munich).

Title: How to Abū Hāšim Meinong

Abstract: Similar to Meinong, Abū Hāšim al-Ǧubbāī (d.933), an Islamic theologian/philosopher, held the view that some objects do not exist. This paper is a comparative study between Meinong’s object theory and Abū Hāšim’s theory of nonexistent objects. Our comparative study will be carried out through three main topics: the characterization principle, objecthood, and the ontological status of existence itself. Moreover, Abū Hāšim and his followers argue that the view that some objects do not exist implies some truth value gaps and/or gluts. We will also discuss two of these arguments.

Hegel’s Logic as Logic and as Metaphysics (Nick Stang)

The Logic and Metaphysics Workshop will meet on November 16th from 4:15-6:15 (NY time) via Zoom for a talk by Nick Stang (Toronto).

Title: Hegel’s Logic as Logic and as Metaphysics

Abstract: In the Encyclopaedia Logic Hegel claims that logic “coincides with” metaphysics (§24). In this talk, I will explain why Hegelian logic (the science of thinking) is identical with metaphysics (the science of being). Along the way, I will also shed light on two of the most obscure aspects of Hegel’s logic: that it involves “movement” and that this movement works by the identification, and resolution, of contradictions.

Towards a Justification Logic for FDE (Eoin Moore)

The Logic and Metaphysics Workshop will meet on November 9th from 4:15-6:15 (NY time) via Zoom for a talk by Eoin Moore (CUNY).

Title: Towards a Justification Logic for FDE

Abstract: In this work-in-progress, I aim to develop a justification logic counterpart to first degree entailment. I produce a logic which is an extension of FDE using justification terms. The results are extended to other paraconsistent logics.

Workshop on Substructural Logics, Hierarchies Thereof, and Solutions to the Liar

The Logic and Metaphysics Workshop and the Saul Kripke Center are hosting a day of talks on substructural Logics, hierarchies thereof, and solutions to the Liar on Friday, October 30, 2020. The schedule, NY time, will be as follows (abstracts can be accessed here):

10.00. Strict/Tolerant and Tolerant/Strict Logics, Melvin Fitting, CUNY.

11.40. Expressibility and the (Un)paradoxicality Paradoxes, Will Nava, NYU.

1.20. Lunch Break.

2.00. What is Meta-inferential Validity?, Chris Scambler, NYU.

3.40. Supervaluations and the Strict-Tolerant Hierarchy, Brian Porter, CUNY.

5.20. End (virtual gathering).

Talks will be on Zoom, and are open to all interested. A link will be sent out on the mailing lists of the Logic and Metaphysics Workshop and the Saul Kripke Center the day before. People not on either of those lists who want to receive the link should email Graham Priest (priest DOT graham AT gmail DOT com). PLEASE FEEL FREE TO PASS ON THIS ANNOUNCEMENT.

The Metaphysics of Epistemic Norms (Lisa Warenski)

The Logic and Metaphysics Workshop will meet on October 26th from 4:15-6:15 (NY time) via Zoom for a talk by Lisa Warenski (CUNY).

Title: The Metaphysics of Epistemic Norms

Abstract: A metanormative theory inter alia gives an account of the objectivity of normative claims and addresses the ontological status of normative properties in its target domain.  A metanormative theory will thus provide a framework for interpreting the claims of its target first-order theory.  Some irrealist metanormative theories (e.g., Gibbard 1990 and Field 2000, 2009) conceive of normative properties as evaluative properties that may attributed to suitable objects of assessment (doxastic states, agents, or actions) in virtue of systems of norms.  But what are the conditions for the acceptability of systems of norms, and relatedly, correctness of normative judgment?  In this paper, I take up these questions for epistemic norms.  Conditions for the acceptability of epistemic norms, and hence correctness of epistemic judgment, will be based on the critical evaluation of norms for their ability to realize our epistemic aims and values.  Epistemic aims and values, in turn, are understood to be generated from the epistemic point of view, namely the standpoint of valuing truth.

A Note on Synonymy in Proof-Theoretic Semantics (Heinrich Wansing)

The Logic and Metaphysics Workshop will meet on November 2nd from 4:15-6:15 (NY time) via Zoom for a talk by Heinrich Wansing (Bochum).

Title: A Note on Synonymy in Proof-Theoretic Semantics

Abstract: The topic of identity of proofs was put on the agenda of general (or structural) proof theory at an early stage. The relevant question is: When are the differences between two distinct proofs (understood as linguistic entities, proof figures) of one and the same formula so inessential that it is justified to identify the two proofs? The paper addresses another question: When are the differences between two distinct formulas so inessential that these formulas admit of identical proofs? The question appears to be especially natural if the idea of working with more than one kind of derivations is taken seriously. If a distinction is drawn between proofs and disproofs (or refutations) as primitive entities, it is quite conceivable that a proof of one formula amounts to a disproof of another formula, and vice versa. The paper develops this idea.

Models, Model Theory, and Modeling (Michael Glanzberg)

The Logic and Metaphysics Workshop will meet on October 19th from 4:15-6:15 (NY time) via Zoom for a talk by Michael Glanzberg (Rutgers).

Title: Models, Model Theory, and Modeling

Abstract: In this paper, I shall return to the relations between logic and semantics of natural language.  My main goal is to advance a proposal about what that relation is.  Logic as used in the study of natural language—an empirical discipline—functions much like specific kinds of scientific models. Particularly, I shall suggest, logics can function like analogical models.  More provocatively, I shall also suggest they can function like model organisms often do in the biological sciences, providing a kind of controlled environment for observations.  My focus here will be on a wide family of logics that are based on model theory, so in the end, these claims apply equally to model theory itself.  Along the way towards arguing for my thesis about models in science, I shall also try to clarify the role of model theory in logic.  At least, I shall suggest, it can play distinct roles in each domain. It can offer something like scientific models when it comes to empirical applications, while at the same time furthering conceptual analysis of a basic notion of logic.