Preference is a key area where analytic philosophy meets philosophical logic. I start with two related issues: reasons for preference, and changes in preference, first mentioned in von Wright’s book The Logic of Preference but not thoroughly explored there. I show how these two issues can be handled together in one dynamic logical framework, working with structured two-level models, and I investigate the resulting dynamics of reason-based preference in some detail. Next, I study the foundational issue of entanglement between preference (...) and beliefs, and relate the resulting richer logics to belief revision theory and decision theory. (shrink)

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)

It is natural to assume that every value bearer must be good, bad, or neutral. This paper argues that this assumption is false if value incomparability is possible. More precisely, if value incommensurability is possible, then there is a fourth category of absolute value, in addition to the good, the bad, and the 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 this paper we introduce a formalism for single-agent decision making that is based on Dynamic Argumentation Frameworks. The formalism can be used to justify a choice, which is based on the current situation the agent is involved. Taking advantage of the inference mechanism of the argumentation formalism, it is possible to consider preference relations, and conflicts among the available alternatives for that reasoning. With this formalization, given a particular set of evidence, the justified conclusions supported by warranted arguments will (...) be used by the agent’s decision rules to determine which alternatives will be selected. We also present an algorithm that implements a choice function based on our formalization. Finally, we complete our presentation by introducing formal results that relate the proposed framework with approaches of classical decision theory. (shrink)

Is an outcome where many people are saved and one person dies better than an outcome where the one is saved and the many die? According to the standard utilitarian justification, the former is better because it has a greater sum total of well-being. This justification involves a controversial form of moral aggregation, because it is based on a comparison between aggregates of different people's well-being. Still, an alternative justification—the Argument for Best Outcomes—does not involve moral aggregation. I extend the (...) Argument for Best Outcomes to show that any utilitarian evaluation can be justified without moral aggregation. (shrink)

Kurt Gödel’s version of the Ontological Proof derives rather than assumes the crucial Possibility Claim: the claim that it is possible that something God-like exists. Gödel’s derivation starts off with a proof of the Possible Instantiation of the Positive: the principle that, if a property is positive, it is possible that there exists something that has that property. I argue that Gödel’s proof of this principle relies on some implausible axiological assumptions but it can be patched so that it only (...) relies on plausible principles. But Gödel’s derivation of the Possibility Claim also needs a substantial axiological assumption, which is still open to doubt. (shrink)