Part I. Ontology
Existence (1987)
Nonexistence (1998)
Mythical objects (2002)
Part II. Necessity
modal logic Kalish-and-Montague style (1994u)
Impossible Worlds (1984)
An empire of thin air (1988)
The logic of what might have been (1989)
Part III. Identity
The fact that X=Y (1987)
This side of paradox (1993)
Identity facts (2002)
Personal identity : what's the problem? (1995u)
Part IV. Philosophy of mathematics
Wholes, parts, and numbers (1997)
The limits of human mathematics (2001)
Part V. Theory of meaning and reference
On content (1992)
On designating (1997u)
A problem in the Frege-Church theory of sense and denotation (1993)
The very possibility of language (2001)
Tense and intension (2003)
Pronouns as variables (2005).