Sven Ove Hansson

Value statements can be divided into three major groups according to how their criteria of evaluation are specified. The first of these groups consists of those value statements that are unspecified with respect to the criteria of evaluation. Here is one example: Her decision was very good. The second group consists of the viewpoint-specified value statements. In these value statements, an explicit point of view is given, from which the evaluation is made. We often use adverbs such as “morally”, “aesthetically” etc. to express this type of specification.

A probabilistic explication is offered of equipoise and uncertainty in clinical trials. In order to be useful in the justification of clinical trials, equipoise has to be interpreted in terms of overlapping probability distributions of possible treatment outcomes, rather than point estimates representing expectation values. Uncertainty about treatment outcomes is shown to be a necessary but insufficient condition for the ethical defensibility of clinical trials. Additional requirements are proposed for the nature of that uncertainty. The indecisiveness of our criteria for cautious decision-making under uncertainty creates the leeway that makes clinical trials defensible.

Formal representations of values and norms are employed in several academic disciplines and specialties, such as economics, jurisprudence, decision theory and social choice theory. Sven Ove Hansson closely examines such foundational issues as the values of wholes and the values of their parts, the connections between values and norms, how values can be decision-guiding and the structure of normative codes with formal precision. Models of change in both preferences and norms are offered, as well as a method to base the logic of norms on that of preferences. Hansson has developed a unified formal representation of values and norms that reflects both their static and their dynamic properties. This formalized treatment, carried out in terms of both informal value theory and precise logical detail, will contribute to the clarification of certain issues in the basic philosophical theory of values and norms.

In the last half century, decision theory has had a deep influence on moral theory. Its impact has largely been beneficial. However, it has also given rise to some problems, two of which are discussed here. First, issues such as risk-taking and risk imposition have been left out of ethics since they are believed to belong to decision theory, and consequently the ethical aspects of these issues have not been treated in either discipline. Secondly, ethics has adopted the decision-theoretical idea that action-guidance has to be based on cause–effect or means–ends relationships between an individual action and its possible outcomes. This is problematic since the morally relevant connections between an action and future events are not fully covered by such relationships. In response to the first problem it is proposed that moral theory should deal directly and extensively with issues such as risk-taking and risk imposition, thereby intruding unabashedly into the traditional territory of decision theory. As a partial response to the second problem it is proposed that moral theorizing should release itself from the decision-theoretical requirement that the moral status of an action has to be derivable from the consequences (or other properties) that are assignable to that action alone. In particular, the effects that an action can have in combination with other actions by the same or other agents are valid arguments in an action-guiding moral discourse, even if its contribution to these combined consequences cannot be isolated and evaluated separately.

Specified meet contraction is the operation defined by the identity where ∼ is full meet contraction and f is a sentential selector, a function from sentences to sentences. With suitable conditions on the sentential selector, specified meet contraction coincides with the partial meet contractions that yield a finite-based contraction outcome if the original belief set is finite-based. In terms of cognitive realism, specified meet contraction has an advantage over partial meet contraction in that the selection mechanism operates on sentences rather than on temporary infinite structures (remainders) that are cognitively inaccessible. Specified meet contraction provides a versatile framework in which other types of contraction, such as severe withdrawal and base-generated contraction, can be expressed with suitably chosen properties of the sentential selector.

Real-life decision-making often begins with a disorderly decision problem that has to be clarified and systematized before a decision can be made. This is the process of decision structuring that has largely been ignored both in decision theory and applied decision analysis. In this contribution, ten major components of decision structuring are identified, namely the determination of its scope, subdivision, agency, timing, options, control ascriptions, framing, horizon, criteria and restructuring. Four of these components, namely the scope, subdivision, options, and horizon of a decision, are subjected to a more detailed analysis.

In order to avoid the paradoxes of standard deontic logic, we have to give up the semantic construction that identifies obligatory status with presence in all elements of a subset of the set of possible worlds. It is proposed that deontic logic should instead be based on a preference relation, according to the principle that whatever is better than something permitted is itself permitted. Close connections hold between the logical properties of a preference relation and those of the deontic logics that are derived from it in this way. The paradoxes of SDL can be avoided with this construction, but it is still an open question what type of preference relation is best suited to be used as a basis for deontic logic.