Prof. David J. Pym

Professor David J. Pym, MA (Cambridge), PhD (Edinburgh), ScD (Cambridge), FIMA, CMath, FBCS, CITP

Professor of Information, Logic, and Security at UCL
Faculty Fellow, Alan Turing Institute

David's UCL CS Page
Department of Computer Science
University College London
Gower Street
London WC1E 6BT

University of London

Research Groups:


PhD studentships currently available

Research Interests

I have worked in a range of areas of mathematical logic and theoretical computer science, including type theory and logical frameworks, proof theory, categorical logic, substructural logic, resource semantics, and process algebra. In theses areas, I have always been particularly interested in the interplay between syntax and semantics.

In recent years, I have become engaged with mathematical systems modelling, with a particular interest in applying --- in the style of classical mathematical modelling as practised in, for example, engineering, where the control of complexity by abstraction is critically important in delivering useful models --- the ideas of compositional semantics and logic to complex systems, particularly in the social sciences and systems engineering. Computer security, system security, and information security provide excellent challenges for this approach. All this began around 2004, with an extended stay with the security research group at HP Labs, initially funded by a Royal Society Industry Fellowship.

My current research interests include the following:

I am always looking for talented and well-prepared PhD students to work with me in these areas.

Here is a link to a page about a film about the logic BI: Attack of the 50 Foot Spatial Dudes.

My latest book, a research monograph entitled A Discipline of Mathematical Systems Modelling, co-authored with Matthew Collinson and Brian Monahan, is published by the not-for-profit publisher College Publications.


The mathematization of the sciences, of engineering, and of economics has been an outstandingly successful intellectual enterprise, enabling the modern world. As the operations of the world become more and more dependent on highly interconnected, massively complex, networked systems of computational devices, the need to develop a mathematical understanding of their properties and behaviours is increasingly pressing.

Our approach, described in this monograph, is to combine the compositionality of formal specification --- using techniques from algebra, computation theory, logic, and probability theory --- with the control of level of abstraction afforded by the classical mathematical modelling method.

The first chapter provides a complete high-level view of the approach to systems modelling that is developed in the monograph. It provides both conceptual and philosophical background and introductions to the technical development. The remaining chapters develop the mathematical and computational aspects of our approach. Each chapter develops a specific mathematical or computational component, clearly integrated into the overall development. Examples, including ones based on industrial and commercial applications, are provided throughout. An implementation of a simulation engine (Core Gnosis) for executing models is available for download from HP Labs. Associated with this monograph is a website ( from which Core Gnosis may be obtained. This is book is about the conceptual and mathematical foundations of a modelling approach, with indications of how it can, and has been, deployed in practice. We defer to another occasion an account of the pragmatics of the deployment.

Available from Waterstones, Amazon UK, Amazon US, Amazon DE, and Amazon FR.

Other Monographs

I am one of the designers of the Core Gnosis tool for systems and security modelling. The Core Gnosis system can be downloaded from HP Labs at, along with a paper

M. Collinson, B. Monahan, and D. Pym,
Semantics for Structured Systems Modelling and Simulation,
Proc. Simutools 2010, ACM Digital Library, ISBN: 978-963-9799-87-5

published at SIMUTools 2010.

Current Funded Projects

Recent Funded Projects (see Recent Publications and Manuscripts for associated papers)