The logic of the interaction between beneficence and respect for autonomy.

Beneficence and respect for autonomy are two of the most fundamental moral duties in general and in bioethics in particular. Beyond the usual questions of how to resolve conflicts between these duties in particular cases, there are more general questions about the possible forms of the interactions between them. Only recognition of the full spectrum of possible interactions will ensure optimal moral deliberation when duties potentially conflict. This paper has two simultaneous objectives. The first is to suggest a typological scheme of all possible modes of interaction; these will be classified under the "discrete," "semi-discrete," and "non-discrete" categories, according to whether the meaning and/or forms of expression of each duty are treated as independent from or rather as constrained by the other. The second objective is to show that all logical possibilities of interaction indeed have real expressions in medical ethics, to provide clear illustrations of each, and in particular to stress those that have usually escaped recognition.