Von Wright’s preference logic reconsidered

A logic of preference does not pertain to the formation of preferences, but rather to a pre-established hierarchy of alternatives, ordered by some underlying relation. A wide variety of relations, corresponding to reasons behind the ordering of alternatives, may be seen as preference relations. For example, alternatives may be ordered by the pleasure or utility they bring about, they may be ranked in terms of being better, nicer, and so on. The logics we will consider abstract from the origin of the preferential alternative hierarchies, and simply assumes that the alternatives are ordered by some preference relation. As it is the custom since the seminal work of von Wright, we assume the relation to be asymmetric and transitive. In section 1, we give a detailed analysis of von Wright’s seminal work [26], entitled The logic of preference. We will see that a key notion in this work is the notion of preferences ceteris paribus (all other things being equal). Section 2 is devoted to tracking down ways to give appropriate semantics to this latter notion. In the last section, we look at the semantics for preference logic proposed in [23], which uses a basic modal language augmented with the existential modality. We will compare this version with von Wright’s original version, and see that the major difference between the two lies in the ceteris paribus clause. This is further investigated in a follow-up paper ([11]). In the appendix are presented alternative approaches to preference by Shoam, Lewis, Huang, and van Benthem and Liu.