In Two Minds conference, Cambridge 2006

Coin with head of Janus

An interdisciplinary conference on dual-process theories of reasoning and rationality, organized by the Department of Philosophy at the Open University, and held at Fitzwilliam College Cambridge on 5-7 July 2006.Organized by Keith Frankish and Carolyn Price of The Open University and Jonathan Evans from the University of Plymouth.This webpage is a record of the event and a home for resources related to it, including abstracts, draft papers, and PowerPoint presentations.


There has been growing interest recently in so-called ‘dual-process’ theories of reasoning and rationality. Such theories postulate two distinct systems (or sets of systems) underlying human reasoning – typically distinguishing an evolutionarily old system (‘System 1’) that is associative, automatic, unconscious, parallel, and fast, and a more recent, distinctively human system (‘System 2’) that is rule-based, controlled, conscious, serial, and slow. On some views, System 1 processes are held to be innate and to employ heuristics which evolved to solve specific adaptive problems, whereas System 2 processes are taken to be learned, flexible, and responsive to rational norms. Widespread cognitive illusions, such as the conjunction fallacy, can be ascribed to System 1, while superior individual performances can be explained as the result of System 2 processes overriding System 1 responses. Some writers also suggest that the two systems are associated with different conceptions of rationality.

This three-day interdisciplinary conference brought together the leading researchers on dual-processes theory the first time in order explore the motivations for different dual-process theories, the connections and contrasts between them, and their implications for various disciplines. The focus was on theoretical aspects of dual-process theory, rather than purely experimental work, and there was special emphasis on the philosophical applications of work in this area.

Papers were invited on dual-process theory itself (versions, critiques, historical perspectives), implications of dual-process theory for debates about rationality, and applications of dual-process theory to issues in other fields, including philosophy.

Here are the conference programme and a booklet containing abstracts of the talks and presentations. (Note: In the event, the talk by Gideon Keren and Yaacov Schul listed in the programme had to be cancelled for health reasons. It was replaced by a talk by Shira Elqayam, expanding on her scheduled poster presentation.)


(Titles links to presentations, where available. Some draft papers are also provided.)

Jean-François Bonnefon (LTC-CNRS, Toulouse), Michael Eid (University of Geneva), Stéphane Vautier and Saïd Jmel (University of Toulouse Le Mirail).
A mixed Rasch model of dual-process conditional reasoning. Draft paper

Sacha Bourgeois-Gironde (Institut Jean-Nicod CNRS-EHESS-ENS, Paris) and Pierre-Stanislas Grialou (ENS, Paris & University of Keio, Tokyo).
What is dual in dual process theories of reasoning? A critical assessment of Goel’s data.

Peter Carruthers (Philosophy, University of Maryland).
An architecture for dual reasoning.

Zoltan Dienes (Psychology, University of Sussex).
Unconscious knowledge and inference.

Shira Elqayam (Psychology, University of Plymouth).
Rationality2: no guide for the perplexed. Draft paper

Jonathan Evans (Psychology, University of Plymouth).
The multiplicity of mind.

Keith Frankish (Philosophy, The Open University).
Dual-process theories and the personal-subpersonal hypothesis.

Vinod Goel (Psychology, York University, Toronto).
Multiple reasoning systems: the case from common sense and neuropsychology.

Paul Klaczynski (Developmental and Learning Sciences, National Science Foundation).
Counterintuitive age trends, dual processing, and the development of irrationality—or, Obesity is contagious, but what does one catch?

Matthew Lieberman (Psychology, UCLA).
Reflective and reflexive processes in social cognitive neuroscience.

Jon May (Psychology, Sheffield) and Philip Barnard (Cognition and Brain Sciences Unit, Cambridge).
Reasoning with complementary pathways not competing processes. Draft paper

Hugo Mercier and Dan Sperber (both Institut Jean Nicod, Paris).
Intuitive and reflective inferential processes.

Agnes Moors (Psychology, Ghent University).
Examining the mapping problem in multi-mode models.

Ara Norenzayan (Psychology, University of British Columbia).
Two systems of thinking across cultures.

Mike Oaksford (Psychology, Birkbeck College London) and Nick Chater (Psychology, University of Warwick).
Dual processes or dual aspects?

David Over (Psychology, University of Sunderland) and Constantinos Hadjichristidis (Management, Leeds University Business School).
The constructive/non-constructive duality and dual process theory.

Valerie Reyna (Human Development, Cornell University).
Dual processes in reasoning and decision making: fuzzy rationality.

Richard Samuels (Philosophy, King’s College London).
The magical number two, plus or minus: Some comments on dual-processing theories of cognition.

Clare Saunders (Subject Centre for Philosophical and Religious Studies, University of Leeds).
In two (or more) minds about rationality? Dual process theory’s contribution to the rationality debate.

Leland Saunders (Philosophy, University of Maryland).
Reason and intuition in the moral life: a rationalist defense of moral intuitions.

Steven Sloman (Cognitive and Linguistic Sciences, Brown University).
How well are two process models standing up to the Bayesian Challenge?

Keith Stanovich (Human Development and Applied Psychology, University of Toronto).
Is it time for a tri-process Theory? Distinguishing the reflective and the algorithmic mind.

Keith Stenning (Human Communication Research Centre, Edinburgh University) and Michiel van Lambalgen.
What are System1 processes like? Defeasible but logical perhaps?

Valerie Thompson (Psychology, University of Saskatchewan).
Dual process theories: questions and outstanding issues.

Poster presentations

Titles link to either presentations or draft papers.

Linden Ball (Psychology, Lancaster University).
The dynamics of reasoning: chronometric analysis and dual process theories.

Matthew Carmody (Philosophy, Richmond-upon-Thames College & King’s College London).
Misunderstanding ourselves: vagueness and two systems of classification.

Aidan Feeney (Applied Psychology, University of Durham).
Inductive reasoning and dual processes.

Uri Leron (Science and Technology Education, Israel Institute of Technology).
Application of dual-process theories in mathematics education (and vice versa).

Fiona Montijn-Dorgelo (Human-technology Interaction, Eindhoven University of Technology).
Impact of dual process models in scientific progress and communication: the case of the role of affect.

Magda Osman (Psychology, University College London).
Undoing one’s learning in an a complex causal inductive task.

Robin Scaife (Philosophy, University of Sheffield).
Dual-process and cognitive checking.

Christopher Viger (Philosophy, University of Western Ontario).
The acquired language of thought hypothesis (ALOT).

Cilia Witteman, John van den Bercken (both Behavioural Science, Radboud University Nijmegen) and Laurence Claes (Psychology, Catholic University Leuven).
Personal preferences for rationality or intuition.

Organizers and Sponsors

Open University logoThe conference was organized by the Philosophy Department of the Open University in conjunction with the University’s Mind Meaning and Rationality Group. The organizing committee consisted of Keith Frankish and Carolyn Price of the Open University and Jonathan Evans of the University of Plymouth. Veli Mitova and Asbjørn Steglich-Petersen helped with the running of the conference itself. Danielle Bertrand of the Arts Faculty of the Open University provided secretarial support during the organization of the event.

The organizers gratefully acknowledge the generous support of the Mind Association, the Economic and Social Research Council, and the Open University.