A possible world semantics for preference is developed. The remainder operator () is used to give precision to the notion that two states of the world are as similar as possible, given a specified difference between them. A general structure is introduced for preference relations between states of affairs, and three types of such preference relations are defined. It is argued that one of them, actual preference, corresponds closely to the concept of preference in informal discourse. Its logical properties are (...) studied and shown to be plausible. (shrink)

This paper presents a new modal logic for ceteris paribus preferences understood in the sense of "all other things being equal". This reading goes back to the seminal work of Von Wright in the early 1960's and has returned in computer science in the 1990' s and in more abstract "dependency logics" today. We show how it differs from ceteris paribus as "all other things being normal", which is used in contexts with preference defeaters. We provide a semantic analysis and (...) several completeness theorems. We show how our system links up with Von Wright's work, and how it applies to game-theoretic solution concepts, to agenda setting in investigation, and to preference change. We finally consider its relation with infinitary modal logics. (shrink)

Some things have positive value and some things have negative value. The things with positive value are good and the things with negative value are bad. There are also things in-between that are neither good nor bad, which are neutral. All in all, then, there are three monadic value predicates: “good,” “bad,” and “neutral.”.

Erik Carlson puts forward a new way of defining monadic value predicates, such as ‘good’, in terms of dyadic value relations, such as ‘better’. Earlier definitions of this kind have the unwanted feature that they rule out some reasonable axiologies by conceptual fiat. Carlson claims that his definitions do not have this drawback. In this paper, I argue that they do.

In the last few years, preference logic and in particular, the dynamic logic of preference change, has suddenly become a live topic in my Amsterdam and Stanford environments. At the request of the editors, this article explains how this interest came about, and what is happening. I mainly present a story around some recent dissertations and supporting papers, which are found in the references. There is no pretense at complete coverage of preference logic (for that, see Hanson 2001) or even (...) of preference change (Hanson 1995). (shrink)