This paper tries to develop an epistemological analysis on the notion of responsibility. After pointing out a peculiar kind of uncertainties concerning the notion of responsibility, I focus upon the issue of criminal responsibility, taking the case of mentally disordered offenders into account, and propose the distinction of the phases between sentence and practice with applying Slobogin's idea of integrationism. Finally, I propose a probabilistic approach to the problem of responsibility through considering the idea of relevance ratio, leading to my (...) final proposal concerning the concept of the degrees of responsibility. (shrink)