This paper inquires the systematical consequences in the Nietzschean critics of the biological determination of life. We proposed an analysis about central topics of this determination: the finalism, the life and chaos. This approach allows us to relieve a systematical conception of what Nietzsche understands by "necessity" (Nothwendigkeit). This conception of necessity is not metaphysic in the traditional sense, but implies a subversion of all special metaphysic. Beyond this, it entails a critical to the transcendental and normative version, own of Kantian thought, about the question of life. These confrontations seek to clarify the gnoseological and ontological areas put in check, on the status of the concept of life.