 
Summary: The Liarparadox in a Quantum Mechanical
Perspective
Diederik Aerts, Jan Broekaert, Sonja Smets
CLEA, Free University of Brussels, Pleinlaan 2, B1050 Brussels
Abstract
We propose a method to model the truth behaviour of cognitive entities
taking into account the possible influence of the cognitive person on the
truth behaviour of the entity. Hereby we specifically apply the mathe
matical formalism of quantum mechanics because of the fact that this
formalism allows the description of real contextual influences, i.e. the
influence of the measuring apparatus on the physical entity. We con
centrated on the typical situation of the liar paradox and have shown
that (1) the truthfalse state of this liar paradox can be represented
by a quantum vector in a finite dimensional complex Hilbert space
and the different interpretative interactions by the actions of the cor
responding quantum projections, (2) the typical oscillations between
false and truth  the paradox  is now quantum dynamically described
by a Schršodinger equation. We analyse possible philosophical implica
tions of this result.
1 Introduction.
