Coin flips, Spinning Tops and the Continuum Hypothesis (Daniel Hoek)

The Logic and Metaphysics Workshop will meet on September 28th from 4:15-6:15 (NY time) via Zoom for a talk by Daniel Hoek (Virginia Tech).

Title: Coin flips, Spinning Tops and the Continuum Hypothesis

Abstract: By using a roulette wheel or by flipping a countable infinity of fair coins, we can randomly pick out a point on a continuum. In this talk I will show how to combine this simple observation with general facts about chance to investigate the cardinality of the continuum. In particular I will argue on this basis that the continuum hypothesis is false. More specifically, I argue that the probabilistic inductive methods standardly used in science presuppose that every proposition about the outcome of a chancy process has a certain chance between 0 and 1. I also argue in favour of the standard view that chances are countably additive. A classic theorem from Banach and Kuratowski (1929), tells us that it follows, given the axioms of ZFC, that there are cardinalities between countable infinity and the cardinality of the continuum. (Get the paper here: https://philpapers.org/archive/HOECAT-2.pdf).

Published
Categorized as Fall 2020

Arithmetical Semantics for Non-Classical Logic (Yale Weiss)

The Logic and Metaphysics Workshop will meet on September 21st from 4:15-6:15 (NY time) via Zoom for a talk by Yale Weiss (CUNY).

Title: Arithmetical Semantics for Non-Classical Logic

Abstract: I consider logics which can be characterized exactly in the lattice of the positive integers ordered by division. I show that various (fragments of) relevant logics and intuitionistic logic are sound and complete with respect to this structure taken as a frame; different logics are characterized in it by imposing different conditions on valuations. This presentation will both cover and extend previous/forthcoming work of mine on the subject.

Published
Categorized as Fall 2020

Cantor’s Theorem, Modalized (Chris Scambler)

The Logic and Metaphysics Workshop will meet on September 14th from 4:15-6:15 (NY time) via Zoom for a talk by Chris Scambler (NYU).

Title: Cantor’s Theorem, Modalized

Abstract: I will present a modal axiom system for set theory that (I claim) reconciles mathematics after Cantor with the idea there is only one size of infinity. I’ll begin with some philosophical background on Cantor’s proof and its relation to Russell’s paradox. I’ll then show how techniques developed to treat Russell’s paradox in modal set theory can be generalized to produce set theories consistent with the idea that there’s only one size of infinity.

(The slides are available here.)

Published
Categorized as Fall 2020

Fall 2020 Schedule

The Logic and Metaphysics Workshop will be meeting on Mondays from 4:15 to 6:15 (NY time) entirely online. The provisional schedule is as follows:

Sep 14. Chris Scambler, NYU

Sep 21. Yale Weiss, CUNY

Sep 28. Daniel Hoek, Virginia Tech

Oct 5. Friederike Moltmann, CNRS Oliver Marshall, UNAM

Oct 12. Brian Porter, CUNY

Oct 19. Michael Glanzberg, Rutgers

Oct 26. Lisa Warenski, CUNY

Nov 2. Heinrich Wansing, Bochum

Nov 9. Eoin Moore, CUNY

Nov 16. Nick Stang, Toronto

Nov 23. Behnam Zolghadr, Hamburg LMU Munich

Nov 30. Mircea Dumitru, Bucharest

Dec 7. Jennifer McDonald, CUNY

Published
Categorized as Fall 2020

Coronavirus Cancellations

Consistent with institutional guidance concerning the coronavirus, all meetings of the Logic and Metaphysics Workshop through Spring break have been cancelled. Contingent upon public health developments, meetings may resume on April 20th.

Consistent with institutional guidance concerning the coronavirus, all meetings of the Logic and Metaphysics Workshop for the remainder of the Spring 2020 semester have been cancelled.

Is There an Absolute Modality? (Antonella Mallozzi)

The Logic and Metaphysics Workshop will meet on March 9th from 4:15-6:15 in room 7395 of the CUNY Graduate Center for a talk by Antonella Mallozzi (Providence College).

Title: Is There an Absolute Modality?

Abstract: Modality seems distinctively pluralistic: there are many kinds of possibility and necessity (logical, physical, metaphysical, normative, etc.), which seem significantly different from one another. However, the various modalities also seem to have much in common–perhaps simply in virtue of being kinds of modality. Should we suppose that there is some fundamental modality, one to which all the other modalities can be somehow reducedModal Monism says yes. Particularly, monists may treat the different modalities as relative to some absolute modality. However, Monism, reductionism, and absolute modality need not be a package. Specifically, the claim that some modality is absolute can be understood in ways which are independent of Monism and reductionism. In this talk, I raise concerns for monistic and reductionist programs in modal metaphysics, while also arguing that the notion of absolute modality is ambiguous. Depending on the framework, it means different things and captures quite different desiderata. After exploring several ways of disambiguating  it, I suggest that while we possess and deploy a concept of absolute modality, that may be empty; or, otherwise put, no modal truth has the property of being “absolute”. I propose a pluralistic picture that still treats the different modalities as relative, while avoiding both absolute modality and reductionism. Importantly, the proposal won’t impact the philosophical significance of metaphysical modality.

 

The Statistical Nature of Causation (David Papineau)

The Logic and Metaphysics Workshop will meet on March 16th from 4:15-6:15 in room 7395 of the CUNY Graduate Center for a talk by David Papineau (CUNY).

Following guidance from CUNY concerning the coronavirus, this event has been cancelled.

Title: The Statistical Nature of Causation

Abstract: For over a hundred years econometricians, epidemiologists, educational sociologists and other non-experimental scientists have used asymmetric correlational patterns to infer directed causal structures. It is odd, to say the least, that no philosophical theories of causation cast any light on why these techniques work. Why do the directed causal structures line up with the asymmetric correlational patterns? Judea Pearl says that the correspondence is a “gift from the gods”. Metaphysics owes us a better answer. I shall attempt to sketch the outline of one.

Published
Categorized as Spring 2020

Deductive Systems with Unified Multiple-Conclusion Rules (Alex Citkin)

The Logic and Metaphysics Workshop will meet on March 2nd from 4:15-6:15 in room 7395 of the CUNY Graduate Center for a talk by Alex Citkin (Metropolitan Telecommunications).

Title: Deductive Systems with Unified Multiple-Conclusion Rules

Abstract: Some people fight for the rights of animals, I am fighting for the rights of rejected propositions. Following the approach suggested by Brentano and accepted and developed by Lukasiewicz, I study the deductive systems that treat asserted and rejected propositions equally, in the same way. By “statement,” we understand the expressions of form +A – “A being asserted”, and -A$ – “A being rejected”, where A is a proposition. Accordingly, by a “unified logic,” we understand a consequence relation between sets of statements and statements. We introduce the unified deductive systems which can be used to define the unified logics. Unified deductive system consists of axioms, anti-axioms, and the multiple conclusion inference rules which premises and conclusions are the statements rather than the propositions. In particular, we study the deductive systems that contain the coherency rule, which means that one cannot assert and reject the same proposition at the same time, and the fullness rule, which means that each proposition is either asserted or rejected. Inclusion of these rules though does not enforce the law of excluded middle, or the law of non-contradiction on the propositional level.

Published
Categorized as Spring 2020

A Truthmaker Semantics for Modal Logics (Dongwoo Kim)

The Logic and Metaphysics Workshop will meet on February 24th from 4:15-6:15 in room 7395 of the CUNY Graduate Center for a talk by Dongwoo Kim (CUNY).

Title: A Truthmaker Semantics for Modal Logics

Abstract: This paper attempts to provide an exact truthmaker semantics for a family of normal modal propositional logic. The new semantics can be regarded as an “exactification” of the Kripke semantics in the sense of Fine (2014). For it offers an account of the accessibility relation on worlds in terms of the banning and allowing relations on states. The main idea is that an exact truthmaker for “Necessarily P” is a state that bans the exact falsifiers of P from obtaining, and an exact truthmaker for “Possibly P” is a state that allows the exact verifiers of P to obtain.

The Power of Naive Truth (Hartry Field)

The Logic and Metaphysics Workshop will meet on February 3rd from 4:15-6:15 in room 7395 of the CUNY Graduate Center for a talk by Hartry Field (NYU).

Title: The Power of Naive Truth

Abstract: While non-classical theories of truth that take truth to be transparent have some obvious advantages over any classical theory that evidently must take it as non-transparent, several authors have recently argued that there’s also a big disadvantage of non-classical theories as compared to their “external” classical counterparts: proof-theoretic strength. Some of them have concluded that this gives a decisive advantage to classical logic theories.  Williamson has argued this too. While conceding the relevance of proof-theoretic strength to the choice of logic, I will argue that there is a natural way to beef up extant internal theories so as to remove their proof-theoretic disadvantage. Given this, the resulting internal theories should seem preferable to their external counterparts.