Abstract

This essay narrates some of the influences that Alasdair Urquhart has had on computer science at the intersection of automated theorem proving, temporal logic and lattice theory—topics that have no obvious relationship to one another. I illustrate this by showing how Allen’s temporal relations are represented in a system for constraint logic programming over intervals and how the combination of a linear-resolution theorem prover and an interval constraint satisfaction system are connected via a lattice-theoretical semantic model. I also speculate on whether some of Thich Nhat Hanh’s meditation teachings might have been one of the sources of Alasdair’s creative inspirations and preternatural capacity for lateral thinking.