Bioethics is an interdisciplinary science. What is the role that philosophy should and could play in this field? This paper addresses these questions.
By accepting the rule of informed consent, bioethics is distinguished from traditional medical ethics. This rule is justified by a general ethical principle, i.e., respect for autonomy. The primary task of philosophy is to propose such basic principles that people involved can use as a common ground for their discussions.
Though people agree on respecting individuals' self decision making, there is no agreement on decisions associated with human being without competence, i.e., embryo, brain-dead, etc. To such issues with conflicting positions, philosophers provide positive or negative arguments based on their own normative theories. This is philosophy's second task.
Bioethics deals with diverse issues, from patient-health provider relationship and usage of new medical technologies to distribution of health resources. Studying even a single case study requires us to consider its complex context. The third task of philosophy is to apply ethical principle and rules in order to put various elements in order and identify the key points of consideration.
In these tasks, a normative theory of philosophy is not simply applied to a biomedical judgment. Both theory and judgment examine one another so that they reach a reflexive equilibrium.

特集 : 西脇与作君・樽井正義君退職記念
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