Signalling in IF games: a tricky business
Theo M.V. Janssen, Francien Dechesne

Abstract:
The paper studies the phenomenon of signalling in logics for imperfect
information, such as Hintikka's IF logic. It is shown that signalling
is a phenomenon that at the one hand is essential for the semantics,
but at the other hand is a source of tricky phenomena. Several
properties which in the literature are claimed to hold for such
logics, turn out to fail due to signalling: IF logic is not a
conservative extension of predicate logic, renaming of variables is
not always allowed, the prenex normal form theorem does not hold, and
slashed connectives cannot easily be eliminated.