In informal mathematical discourse (such as the text of a paper on theoretical computer
science), we often reason about equalities involving binding of object-variables. We find …

We are used to the idea that computers operate on numbers, yet another kind of data is
equally important: the syntax of formal languages, with variables, binding, and alpha …

Substitution is fundamental to the theory of logic and computation. Is substitution something
that we define on syntax on a case-by-case basis, or can we turn the idea of substitution into …

The practice of first-order logic is replete with meta-level concepts. Most notably there are
the meta-variables themselves (ranging over predicates, variables, and terms), assumptions …

In informal mathematical usage we often reason using languages with binding. We usually
find ourselves placing capture-avoidance constraints on where variables can and cannot …

Substitution is fundamental to computer science, underlying for example quantifiers in
predicate logic and beta-reduction in the lambda-calculus. So is substitution something we …

This dissertation explores the roles of polarities and focussing in various aspects of
Computational Logic. These concepts play a key role in the the interpretation of proofs as …

We introduce permissive nominal terms, and their unification. Nominal terms are one way to
extend first-order terms with binding. However, they lack some useful properties of first-and …

In informal mathematical usage we often reason about languages involving binding of object-
variables. We find ourselves writing assertions involving meta-variables and capture …

Two-level lambda-calculus is designed to provide a mathematical model of capturing
substitution, also called instantiation. Instantiation is a feature of the 'informal meta-level'; it …