It is typical of Choumnos’ approach that he seeks to argue philosophically, that is by valid inference from principles and definitions that are universally accepted, for views that are already theologically established. Thus he attempts to refute Aristotle’s theory that the heavens are composed of a fifth, naturally ungenerable and imperishable body, not by simply appealing to the Christian doctrine that the world was created at the beginning of time and persists only through the grace of its cr