Brandon Bennett and Antony Galton
Artificial Intelligence, Volume 153, Issues 1-2, Pages 13-48 (March 2004).
This paper is a further development in the work reported in Bennett and Galton 2001.
Abstract
We give a formal semantics for a highly expressive language for representing
temporal relationships and events. This language, which we call Versatile
Event Logic (VEL), provides a general temporal ontology and semantics
encompassing many other representations. The system incorporates a number of
features that have not been widely employed in AI formalisms. It has the
ability to describe alternative histories using a modal operator. It provides
a semantics for individuals that explicitly models their identity through
time and across alternative possible histories; and enables one to distinguish
between necessary and extensional identity of individuals. In virtue of its
treatment of individuals and count nouns, the formalism offers a solution to
certain puzzles of identity, which arise when individuals are described in
different ways. We propose that VEL can be used as a foundational interlingua
for comparing and interfacing different AI languages and illustrate by
considering how Situation Calculus and Event Calculus can be represented
within VEL.