TIME, ACTION-TYPES, AND CAUSATION - AN INTEGRATED ANALYSIS

In this paper we focus on the temporal constraints between causes and effects of causal relations, and, to deal correctly with such relation s, we stress the importance of analyzing the action-types (aspectual c ategory) of causes and effects. In particular, we propose a domain-ind ependent ontology in which the distinctions between action-types (e.g. , the distinction between durative and punctual situations) are dealt with, and different types of causal relations are distinguished, on th e basis of (i) the temporal constraints they impose between causes and effects (these constraints are expressed in a temporal formalism that extends Vilain's point interval algebra) and (ii) the action-types of their causes and effects. Our ontology allows one to capture precisel y the temporal constraints imposed by causation and the action-types o f the related situations. Moreover, in case the user has no accurate k nowledge about the action-types of some situations and/or the types of some causal connections to be dealt with, our formalism allows the us er to leave the descriptions underspecified, and more specific pieces of information may be inferred. Inferences provide a flow of informati on about action-types to information about temporal constraints in cau sation and vice versa, and demonstrate that a deep integration of time and causation is provided also at the inferential level.