And the idea which I wish to insist on is not, therefore, the idea of the human good, but the more fundamental idea of good the idea, with regard to which he holds that the working of our minds in some excellent fashion is the only good thing that any of us can possess; and the idea of which better is the comparative, when he says that mental activity which exhibits some sorts of excellence is better than mental activity which exhibits others, though both are good, and that excellent mental activity continued over a longer time is better than the same continued for a shorter.