Computation and Intension
The Plurals, Predicates, and Paradox Research Seminar, Summer Term 2012
Walter Dean (Warwick), Sean Walsh (Birkbeck)
The seminar will explore the development of intensional logic (broadly in the tradition of
Frege, Church, and Montague) to treat problems in philosophy of language as well as the
intensional and epistemic paradoxes. We will also consider the procedural understanding
of intensional entities (as developed by Dummett, Tichý, Moschovakis, and others), and
attempts to formalize this understanding using techniques from computability theory and
theoretical computer science. Some of our focal questions will be:
(i) What purposes are intensional notions (e.g. properties, propositions, Fregean senses and
thoughts) expected to serve and what is their relationship with their extensional counterparts
(e.g. sets, classes, functions, and truth values)?
(ii) Are there paradoxes pertaining specifically to intensional notions? If so, what is their
relationship to the set-theoretic and semantic paradoxes?
(iii) Is there a unified procedural or computational understanding of intensional notions?
If so, what conceptual work should we expect this notion to do – e.g. how are procedures
related to sets or functions? Is there a “naive theory” of procedures? If so, is it consistent?
(iv) A wide range of technical tools from both logic and theoretical computer science have
been applied to formalize reasoning about intensional phenomena – e.g. first- and higherorder modal logic, type theory, lambda calculus, inductive definitions, fixed point semantics.
How are these formalisms related and what philosophical considerations motivate their applications?
In addition to sessions led by Mahrad Almotahari (Philosophy, Birkbeck), Marianna Antonutti Marfori (Philosophy, Bristol), and Jönne Speck (PPP), the external speakers include:
Samson Abramsky (Computer Science, Oxford), Melvin Fitting (Philosophy, Math, Computer Science, CUNY), Peter Fritz (Philosophy, Oxford), Leon Horsten (Philosophy, Bristol),
Kevin Klement (Philosophy, UMass), and Raymond Turner (Computer Science, Essex).
This seminar is open to all interested research students and faculty. The first session is
Friday April 27, 13:15-14:45, McFetridge Room, 14 Gower St., Philosophy Department,
Birkbeck [map](see schedule on the next page for more details). If you have any questions
about the seminar, or want to be added to the dropbox and mailing list, please
Contact: Walter Dean (w.h.dean@warwick.ac.uk) or Sean Walsh (swalsh108@gmail.com)
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Schedule
Session 1: Friday 27 April (London Week 1)
Location: McFetridge Room, 14 Gower St., Philosophy Department, Birkbeck [map]
Seminar (13:15-14:45): Introduction: intension versus extension and the role of procedures
Session 2: Friday 4 May (London Week 2)
Location: McFetridge Room, 14 Gower St., Philosophy Department, Birkbeck [map]
Seminar (13:15-14:45): Background on intensional logic (Frege, Church, Montague, Tichý)
Session 3: Friday 11 May (London Week 3)
Location: McFetridge Room, 14 Gower St., Philosophy Department, Birkbeck [map]
Seminar (13:15-14:45): Two-Dimensional Semantics and the Method of Intension and Extension
(session led by Mahrad Almotahari)
Session 4: Friday 18 May (London Week 4)
Location: McFetridge Room, 14 Gower St., Philosophy Department, Birkbeck [map]
Seminar (13:15-14:45): Russell-Myhill Paradox & Tucker-Thomason on Paradoxes of Intensionality
Speaker (15:00-16:30): Peter Fritz (Oxford), A Logic for Two-Dimensional Semantics
Session 5: Friday 25 May (London Week 5)
Location: STB2 (basement level) Stewart House [map]
Seminar (13:15-14:45): Epistemic Arithmetic, Reinhardt’s argument, and Church’s Thesis (session
led by Marianna Antonutti Marfori)
Speaker (15:00-16:30) Kevin Klement (UMass Amherst) “Russell’s Theory of Incomplete Symbols
and the Paradoxes”
Session 6: Friday 1 June (London Week 6)
Location: S264 (second floor) Senate House [map]
Seminar (13:15-14:45): The recursion theorems and domain theory
Speaker (15:00-16:30): Leon Horsten (Bristol) “Epistemic Church’s Thesis”
Session 7: Friday 8 June (London Week 7)
Location: STB3 (basement level) Stewart House [map]
Seminar (13:15-14:45): Around and about programming language semantics
Speaker (15:00-16:30): Samson Abramsky (Oxford) “Programs as data and intensional recursion”
Session 8: Friday 15 June (London Week 8)
Location: G35 (ground floor) Senate House [map]
Seminar (13:15-14:45): Moschovakis’s theory of algorithms, intensional logic, and synonymy
Speaker (15:00-16:30): Raymond Turner (Essex) TBA
Session 9: Friday 22 June (London Week 9)
Location: McFetridge Room, 14 Gower St., Philosophy Department, Birkbeck [map]
Seminar (13:15-14:45): Kripke and de re beliefs about natural numbers
Session 10: THURSDAY 28 June (London Week 10)
Location: TBA
Seminar (13:15-14:45): Fixed point semantics (session led by Jönne Speck)
Speaker (15:00-16:30): Melvin Fitting (CUNY) “Bilattices in Logic Programming and the Theory
of Truth”
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