Title
From IF to BI
Abstract
We take a fresh look at the logics of informational dependence and independence of Hintikka and Sandu and Väänänen, and their compositional semantics due to Hodges. We show how Hodges’ semantics can be seen as a special case of a general construction, which provides a context for a useful completeness theorem with respect to a wider class of models. We shed some new light on each aspect of the logic. We show that the natural propositional logic carried by the semantics is the logic of Bunched Implications due to Pym and O’Hearn, which combines intuitionistic and multiplicative connectives. This introduces several new connectives not previously considered in logics of informational dependence, but which we show play a very natural rôle, most notably intuitionistic implication. As regards the quantifiers, we show that their interpretation in the Hodges semantics is forced, in that they are the image under the general construction of the usual Tarski semantics; this implies that they are adjoints to substitution, and hence uniquely determined. As for the dependence predicate, we show that this is definable from a simpler predicate, of constancy or dependence on nothing. This makes essential use of the intuitionistic implication. The Armstrong axioms for functional dependence are then recovered as a standard set of axioms for intuitionistic implication. We also prove a full abstraction result in the style of Hodges, in which the intuitionistic implication plays a very natural rôle.
Year
DOI
Venue
2009
10.1007/s11229-008-9415-6
Synthese
Keywords
DocType
Volume
Independence-friendly logic,Dependence logic,Branching quantifiers,Logic of bunched implications,Functional dependence,Full abstraction,Tarski semantics,Team semantics,Quantifiers as adjoints
Journal
167
Issue
ISSN
Citations 
2
0039-7857
10
PageRank 
References 
Authors
0.64
15
2
Name
Order
Citations
PageRank
Samson Abramsky13169348.51
Jouko Väänänen213120.60