Progic 2002

4th – 6th November 2002
4th Augustus de Morgan Workshop
King’s College London

Example Questions

  • How is probability related to logic?
  • Should probability and logic be combined?
    • If so, how?


Bayesianism tells us we ought to reason probabilistically. In that sense, probability theory is logic. How then does probability theory relate to classical logic and the various non-classical logics that also stake a claim on normative reasoning? Is probability theory to be preferred over other logics or vice versa? Is probability theory to be used in some situations, and the other logics in other situations? Or should probability be combined with other logics?

These questions were important in the time of Augustus de Morgan. Indeed de Morgan himself argued that Aristotelian logic was unnecessarily restrictive in scope, and with his contemporary George Boole he began to broaden its horizons, initiating a rennaissance in logic. The title of his most important book bears witness to his vision of a comprehensive logic encompassing probability: “Formal Logic; or the calculus of Inference, Necessary, and Probable”.

While the above questions are not new, we now urgently require some answers. Artificial intelligence is one key discipline in which probability theory competes with other logics for application. It is becoming vitally important to evaluate and integrate systems that are based on very different approaches to reasoning, and there is strong demand for theoretical understanding of the relationships between these approaches.

The aim of the workshop is to address the relationship between probability and logic from an interdisciplinary perspective. We hope that the themes of this workshop will be of interest to mathematicians, logicians, philosophers, computer scientists and engineers.

The attendence fee is £15 – £10 for students.
If you would like to attend please contact Jane Spurr.
The workshop will take place in the Great Hall, King’s College, Strand, London.

NB. We are offering attendees facsimile copies of two relevant books by de Morgan – “Probability” and “Formal Logic” – in paperback edition for £12 each. Please reserve your copies with Jane Spurr by October 17th.


Monday 4th November

  • 09.30-10.00 Registration
  • 10.00-11.00 Dov Gabbay: Introduction.
  • 11.30-13.00 Henry E. Kyburg Jr.: “Are there degrees of belief?”
  • 14.00-15.30 Colin Howson: “Combining probability and logic”
  • 16.00-17.30 James Cussens: “Leibniz and Boole on logic and probability”

Tuesday 5th November

  • 09.30-11.00 Joseph Halpern: “From statistics to belief”
  • 11.30-13.00 Jeff Paris: “Some consequences of common sense for probabilistic reasoning”
  • 14.00-15.30 Juerg Kohlas: “Probabilistic Argumentation”
  • 16.00-17.30 Rachel Bourne: “Explaining default intuitions using maximum entropy”

Wednesday 6th November

  • 09.30-11.00 Peter Flach: “Probabilistic models for structured data”
  • 11.30-13.00 Stephen Muggleton: “Learning structure and parameters of Stochastic Logic Programs”
  • 14.00-15.30 John Fox: “Reasons to believe and grounds for doubt”
  • 16.00-17.30 Questions and Discussion

NB. Theo Kuipers can no longer attend for medical reasons.

Local Information


London is quite expensive for accommodation, but the following alternatives are at the lower end of the price range:

  • City of London Youth Hostel – £20 under 18 / £24 over 18, per night bed and breakfast;
  • Hotel Strand Continental – 143 Strand, London WC2R 1JA. Tel. +44 20 7836 4880. Fax. +44 20 7379 6105. Single room £32, Double room £40, Family room £50, Twin room £45, Triple room £55. Prices include breakfast. This hotel is for those who favour convenience (it is right next to King’s College) and cuisine (it contains the authentic India Club restaurant) over comfort.
  • Cosmo Bedford House Hotel. 27 Bloomsbury Square, London WC1 2QA. Tel. +44 20 7636 4661. Fax. +44 20 7636 0577. Email. Single room £38, Double room £50.


  • King’s College has a basic canteen in the student’s union building.
  • The India Club (143 Strand) serves authentic indian cuisine.
  • There is a Thai restaurant and a Pizza Express in the same row of buildings.
  • Sarastro Restaurant – 126 Drury Lane – Turkish Food – early evening ‘tenor menu’ £10


  • Paco Pena Flamenco Dance Company – Tuesday 5th & Wednesday 6th – Peacock Theatre, Portugal St – 020 7863 8222
  • Zakir Hussain and the Masters of Percussion – Monday 4th – Royal Festival Hall – 020 7960 4242
  • Kimmo Pohjonen (eclectic accordian music) – Tuesday 5th – Queen Elizabeth Hall – 020 7960 4242
  • Galileo Galilei (Philip Glass opera) – Tuesday 5th & Wednesday 6th – Barbican Theatre – 020 7638 8891
  • Missa pro defunctis by Lobo (candlelit choral requiem for All Souls) – Tuesday 5th 5.30pm – King’s College Chapel


We are grateful to the London Mathematical Society, the British Society for the Philosophy of Science and the British Logic Colloquium for financial support.
Organised by and Group of Logic and Computation, King’s College London.