The essay-like structure of the film explores how different worldviews react to the impossible:
John’s need to move every ten years to hide his lack of aging highlights the isolation that accompanies immortality. Critical Perspectives The Man From Earth - a serious disappointment : r/TrueFilm
John argues that an immortal man wouldn't be a genius; he would simply have more time to learn what the human species knows at any given moment. Core Philosophical Themes