Sven Ove Hansson

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.

Contrary to the received view, decision theory is not primarily devoted to instrumental (ends-to-means) reasoning. Instead, its major preoccupation is the derivation of ends from other ends. Given preferences over basic alternatives, it constructs preferences over alternatives that have been modified through the addition of value object modifiers (modes) that specify probability, uncertainty, distance in time etc. A typology of the decision-theoretical modes is offered. The modes do not have (even extrinsic) value, but they transform the value of objects to which they are applied. A rational agent's total set of preferences should be coherent, but from this it does not follow that her preferences over mode-containing objects have to be derivable from her preferences over mode-free objects.

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.

When presented with a situation involving an agent’s choice between alternative actions, a moral oracle says what the agent is allowed to do. The oracle bases her advice on some moral theory, but the nature of that theory is not known by us. The moral oracle’s test consists in determining whether a series of questions to the oracle can be so constructed that her answers will reveal which of two given types of theories she adheres to. The test can be applied to moral theories in order to determine if they differ in their recommendations for action. Based on this test, a terminology is developed to specify different forms and degrees of distinguishability between moral theories, or types of theories, in terms of their recommendations for action. In conclusion, the test is applied to consequentialism and utilitarianism.

The purpose of this presentation is to introduce both the concept of risk and the precautionary principle, that is a major policy principle in present-day risk management. Since risk has been the subject of many misconceptions I will do this in large part by criticizing seven views on risk that I believe to have caused considerable confusion both among scientists and policy-makers. But before looking at the seven myths of risk, let us begin with the basic issue of defining “risk”. The word “risk” often refers, rather vaguely, to situations in which it is possible but not certain that some undesirable event will occur. In addition, the word has several more specialized meanings. Let me illustrate this by making a few statements about the single most important preventable health hazard in non-starving countries. First: “Lung cancer is one of the major risks that affect smokers.” Here, we use “risk” in the following sense: (1) risk = an unwanted event which may or may not occur. 1 (15).

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.