**PAPERS**

A proposition is*“A Complete Logic of Ground I: Unilateral Propositions” RSL (R&R)**specific*just in case there is exactly one way for that proposition to obtain, and one proposition*grounds*another just in case every way for the former to obtain is a way for the latter to obtain. This paper provides a proof system for a unilateral logic of ground with a specificity operator, establishing soundness and completeness over a state semantics in which propositions are sets of states closed under finite fusion.Having established soundness and completeness for a unilateral logic of ground with a specificity operator in a previous paper, this paper extends these results to a bilateral logic where propositions are closed under infinite fusion. By contrast with the Boolean lattices described by extensional and intensional logics, the space of bilateral propositions forms a non-interlaced bilattice. I will conclude by defining the bilateral notions of essence and ground in terms of unilateral ground.*“A Complete Logic of Ground II: Bilateral Propositions” RSL (R&R)*This paper develops a theory of propositional identity which distinguishes necessarily equivalent propositions that differ in subject-matter. Rather than forming a Boolean lattice as in extensional and intensional semantic theories, the space of propositions forms a non-interlaced bilattice. After motivating a departure from tradition by way of a number of plausible principles for subject-matter, I will provide a Finean state semantics for a novel theory of propositions, presenting arguments against the convexity and nonvacuity constraints which Fine (**“Identity and Aboutness” JPL***Journal of Philosophical Logic*,*4545*, 199–226 13, 14, 15) introduces. I will then move to compare the resulting logic of propositional identity (PI^{1}) with Correia’s (*The Review of Symbolic Logic, 9*, 103–122 9) logic of generalised identity (GI), as well as the first degree fragment of Angell’s (2) logic of analytic containment (AC). The paper concludes by extending PI^{1}to include axioms and rules for a subject-matter operator, providing a much broader theory of subject-matter than the principles with which I will begin.

**PAST TALKS**

**“Formal Foundations for the Logic of Essence and Ground”**

** Wollheim Society**

** Berkeley: 21.9.18**

**“Philosophical Foundations for the Logic of Essence and Ground”**

** Wollheim Society**

** Berkeley: 8.9.18**

**“Grounding and Dependence”**

** Philiminality (Panel)**

** Oxford: 4.5.18**

**“The Logic of Determination”**

** DPhil Seminar**

** Oxford: 5.5.17**

**“Reductionism About Ground”**

** TWiP**

** Oxford: 18.11.16**

**“Reductionism About Ground”**

** Grounding Grounding**

** Alghero: 28.10.16 – 29.10.16**

**“Grounding on the Cheap”**

** Pop Grunch**

** Oxford: 6.6.16**

**“A Real Definition of Non-Actuality”**

** Ockham Society**

** Oxford: 21.10.15**

**“Early Interpretations of the Barcan Formula”**

** Women in Early Analytic Philosophy**

** Ghent: 5.10.15**

**“Getting Down to the Ground”**

** Ockham Society**

** Oxford: 20.11.14**

# CONFERENCES & SOCIETIES

Jowett Society

Co-organiser

Oxford: 2016-17

Structure in Metaphysics

Organised with Annina Loets

Oxford: 30.5.2015 – 1.6.2015

Jowett Society

Co-organiser

Oxford: 2015-16

# READING GROUPS

MLE Seminar

Co-organiser

Oxford: 2015-18

Modal Logic as Metaphysics

Co-organiser

Oxford: Trinity 2015

Modal Logic as Metaphysics

Co-organiser

Berkeley: Summer 2014

Writing the Book of the World

Attended

Harvard/MIT: Spring 2012

# HANDOUTS

Angellic Content

Oxford: 6.11.2015