In my recent article, I addressed the question of whether a potential categorical exclusion of decisionally impaired patients from non-therapeutic medical research would be inaccordance with the Principle of Justice as Fairness. I came to the conclusion that a categorical exclusion of decisionally impaired persons from relevant research projects may collide with Rawls’s understanding of Justice as Fairness. Derek Bell has criticized my paper by denying that it is legitimate to apply Rawls to this bioethical problem. In my restatement I (...) try to show that an extrapolation of John Rawls’s thought to such bioethical cases is possible, because Rawls himself has written that his orientation towards decisionally non-impaired persons is an idealized situation that allows extrapolations. In a second part I try to show that Bell hasroughly misunderstood my concept of “presumed consent” which I make a prerequisite for the legitimisation of research on decisionally impaired persons. In using advance consent as a proposal for resolving the problem, Bell has indirectly confirmed my approach because he is using a similar construct of consent, which operates with similar hypotheses and probabilities of error. I see here no categorical difference between Bell’s conclusion and my discussion. Thus, Bell’s reply does not represent a refutation of my thoughts, but rather it is a para phrased confirmation of my central theses. I conclude by showing the relevance of Rawls, pointing out that the discussion between Bell and me illustrates how Rawls’s concept of reflective equilibrium is an appropriate approach to finding a solution to this bioethical problem. (shrink)