Conjunctive causes are causes that all need to be present for an effect to occur. They contrast with independent causes that by themselves can each bring about an effect. We extend existing “causal power” representations of independent causes to include a representation of conjunctive causes. We then demonstrate how independent vs. conjunctive representations imply sharply different patterns of...

Handling preferences in presence of constraints is an important concept in many applications. The main purpose of this paper is to provide a new non-classical logic for representing and reasoning with preferences and functional constraints in uncertain environments. This logic, called Conjunctive Choice Logic (CCL), aims to determine feasible solutions in such environments and evaluate their sa...

In this extended commentary I discuss the problem of how to account for “conjunctive” readings of some sentences with embedded disjunctions for globalist analyses of conversational implicatures. Following Franke (2010, 2009), I suggest that earlier proposals failed, because they did not take into account the interactive reasoning of what else the speaker could have said, and how else the hearer...

This paper discusses eecient detection of global predicates in a distributed program. Previous work in detection of global predicates was restricted to predicates that could be speciied as a boolean formula of local predicates. Many properties in distributed systems, however, use the state of channels. In this paper, we introduce the concept of a channel predicate and provide an eecient algorit...

Query containment for conjunctive queries is the problem of checking whether a query q is contained in another query q′ with respect to a given Description Logic schema S. It is known that query containment can also be used to answer queries. Query containment is important in many areas, including information integration, query optimisation, and reasoning about Entity-Relationship diagrams, whi...

Memories serve to establish some permanence to our inner lives despite the fleeting nature of subjective experience. Most neurobiological theories of memory assume that this mental permanence reflects an underlying cellular permanence. Namely, it is assumed that the cellular changes which first occur to store a memory are perpetuated for as long as the memory is stored. But is that really the c...

EL is a rather expressive description logic (DL) that still admits polynomial time inferencing for many reasoning tasks. Conjunctive queries are an important means for expressive querying of DL knowledge bases. We address the problem of computing conjunctive query entailment for EL knowledge bases. As it turns out, querying unrestricted EL is actually undecidable, but we identify restrictions u...

EL is a rather expressive description logic (DL) that still admits polynomial time inferencing for many reasoning tasks. Conjunctive queries are an important means for expressive querying of DL knowledge bases. In this paper, we address the problem of computing conjunctive query entailment for EL knowledge bases. As it turns out, querying unrestricted EL is actually undecidable, but we identify...

We provide axiomatic characterizations of two natural families of rules for aggregating equivalence relations: the family of join aggregators and the family of meet aggregators. The central conditions in these characterizations are two separability axioms. Disjunctive separability, neutrality, and unanimity characterize the family of join aggregators. On the other hand, conjunctive separability...