 The insistence upon the binding force of eternal law and the natural human inclination towards, and participation in, it (which is called natural law) marks a decisive step away from Aristotle’s ethics of phronesis. The ground of moral action is no longer thought to be the conformity of conduct to that of an outstanding person (phronimos); it is found in an external and universally binding source (eternal law). The process of correct practical reasoning is governed, and measured, by the conformity of acts to the precepts of this law: