FOM: Conference: Self-reference

Vincent Fella Hendricks vincent at
Thu Jun 27 07:18:40 EDT 2002

October 31 - November 2, 2002
Roskilde University, Denmark
Computer Science
Host: PHILOG - The Danish Network for Philosophical Logic and Its Applications
Sponsor: The Danish Research Council for the Humanities
Email: vincent at

Organizers: PHILOG - The Danish Network for Philosophical Logic and Its 
Applications, Directors: Vincent F. Hendricks, Stig Andur Pedersen

Conference Chair: Vincent F. Hendricks, Stig Andur Pedersen
Speakers: A. Cantini, M. Fitting, A. Gupta, V. McGee, D. Perlis, G. Priest, 
R. Smullyan, S. Yablo

Self-reference is used to denote any situation in which someone or 
something refers to itself. Self-reference is an important issue in 
philosophy, mathematics and computer science amongst other fields. In the 
philosophy of language the naive theory of truth has been challenged by the 
Liar Paradox. The Liar Paradox is the contradiction that emerges from 
trying to determine whether the sentence
"This sentence is false'"
is true or false. The sentence is obviously self-referential in that it 
claims itself to be false. Similarly, in mathematics the naive concept of 
set has been challenged by Russell's paradox. Russell's paradox is the 
contradiction that emerges from trying to determine whether the sentence
"Is the set of all sets that are not members of themselves an element of 
is true or false. This sentence, as well, involves self-reference, though 
maybe not in an as obvious way as the Liar sentence. In computer science 
one of the important problems is the question of how to implement 
introspection (self-reflection) in artificial intelligence agents. Through 
introspection an agent is able to refer to himself. On the naive account of 
agent introspection this again leads to a paradox of self-reference, e.g. 
in the form of the Knower's Paradox:
"I know that what I say now is not true."
In the light of these paradoxes the naive theories have to be abandoned and 
several new, consistent theories have been introduced instead. In these 
theories the paradoxes are avoided either by blocking self-reference 
altogether or by finding consistent ways to treat self-reference. The 
blocking strategy will most often result in theories that are limited in 
important ways. Thus, to construct powerful, consistent theories one has to 
get to a deeper theoretical understanding of self-reference and of how to 
live consistently with it. It turns out that all three paradoxes above are 
structurally similar. This implies that coming to an understanding of the 
basic structure involved in self-reference and theoretically investigate 
how to tame it has promising perspectives for all three fields of research. 
Self-reference is not in any way restricted to occur only in the theories 
considered above. Actually, any theory that could be considered to be part 
of its own subject matter has some degree of self-referentiality. This 
applies to many theories of language, economy, sociology, psychology, etc. 
With respect to these theories an understanding of self-reference is 
essential to avoid performing unsound self-referential reasoning as in the 
paradoxes above.

The aim of the conference is to bring together researchers in the fields of 
philosophy, mathematics, and computer science to present theories of and 
related to self-reference - especially pertaining to theories that explain 
and resolve the above paradoxes and thereby advance new theories for the 
involved fields.
All lectures will be of such a nature that they can be followed by students 
and scholars of philosophy, computer science, linguistics etc. without deep 
professional training in epistemic logic but provided with general 
knowledge of foundational issues.

Mail Address:
PHILOG - The Danish Network for Philosophical Logic and Its Applications

Department of Philosophy and Science Studies, Roskilde University, PA6, P. 
O. Box 260, DK4000 Roskilde, Denmark, Phone: (+45) 4674 2343, Fax: (+45) 
4674 3012

Vincent F. Hendricks, PHD
Associate Professor of Epistemology, Logic and Methodology
Director of PHILOG
Dept. of Philosophy and Science Studies
University of Roskilde, PA 6
P.O. Box 260, 4000 Roskilde
Phone: (+45) 4674 2343
Fax: (+45) 4674 3012

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